急診筆記

細菌性腸炎

2011-07-01T03:33:00.000-07:00

Invasive Bacterial Enteropathies

How do patients with invasive enteropathies present?
Patients with acute invasive enteropathies typically present with fever and frequent bowel movements that contain mucus or blood or both; the mucus or blood often contains leukocytes.

What are the causes of invasive bacterial enteropathies?
Causes of invasive bacterial enteropathies in adults include campylobacteriosis, salmonellosis, shigellosis, enteroinvasive Escherichia coli, and yersiniosis, among others. Vibrio parahaemolyticus, which is most commonly reported in Asia, can cause either bloody or watery diarrhea and is usually associated with the ingestion of seafood.

When is microbiologic evaluation of stool indicated?
Microbiologic evaluation of stool is not usually indicated for most travelers with acute watery diarrhea, such as this patient, since the illness is usually self-resolving or can be treated empirically with hydration, agents that control symptoms, or antimicrobial agents. In contrast, microbiologic evaluation of stool is usually indicated for patients with evidence of an invasive enteropathy, those with persistent diarrhea, and those whose illness is part of an outbreak that has potential public health importance and has an uncertain cause.

What is the recommended treatment for travelers’ diarrhea?
Azithromycin is an agent of choice for the treatment of persons with cholera and those with travelers’ diarrhea. Many strains of campylobacter are now resistant to fluoroquinolones, and the Haitian strain of cholera has reduced susceptibility to ciprofloxacin, a pattern associated with clinical and microbiologic failure in cholera patients.

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NEJM Teaching Topics
June 30, 2011

急診留觀可減少小兒頭部外傷病患做斷層掃描

2011-05-27T18:31:00.000-07:00

Emergency Department Observation of Children with Minor Head Injury Reduces Use of Computed Tomography
But does not impair identification of clinically important traumatic brain injuries

In a secondary analysis of data from the Pediatric Emergency Care Applied Research Network, researchers evaluated whether observing children (age, less than 18 years) with minor head injury before deciding whether to obtain a head computed tomography (CT) scan affects use of CT and diagnosis of traumatic brain injury (TBI). Data on duration of observation were not collected.

Of 40,113 patients (median age, 5.6 years), 5433 (14%) were observed. Observed patients were significantly less likely to undergo CT than patients who were not observed (31% vs. 35%). After adjustment for clinical covariates, the likelihood of CT scanning remained lower for patients who were observed (adjusted odds ratio, 0.53). Rates of clinically important TBI (defined as intracranial injury resulting in death, neurosurgical intervention, intubation for more than 24 hours, or hospital admission for 2 or more nights) were similar between groups (0.75% and 0.87%, respectively).

The authors conclude that observing intermediate-risk patients would result in approximately 39 fewer CT scans per 1000 children who present to the emergency department with blunt head trauma; intermediate-risk children were defined as those with normal mental status and no evidence of skull fracture and at least one of the following: loss of consciousness, severe mechanism of injury, vomiting, not acting normally per parents (children less than 2 years), or severe headache (children above 2 years).

Comment: The lack of data on duration of observation makes practical application of these findings difficult. However, neurologically normal children with a history of loss of consciousness, transient vomiting, or headache can be observed before deciding about CT. Children with persistent symptoms or any sign of clinical deterioration should undergo immediate CT.

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Katherine Bakes, MD
Published in Journal Watch Emergency Medicine May 27, 2011

Citation(s): Nigrovic LE et al. The effect of observation on cranial computed tomography utilization for children after blunt head trauma. Pediatrics 2011 Jun; 127:1067.

視神經超音波可以評估腦壓

2011-05-20T23:55:00.000-07:00

Optic Nerve Ultrasound Predicts Elevated Intracranial Pressure
In a small meta-analysis, ultrasound measurement of optic nerve sheath diameter had a sensitivity of 90% for predicting elevated ICP.

Bedside emergency department ocular ultrasound is increasingly used to detect retinal detachment, but does it also have other uses? Researchers performed a meta-analysis of six prospective studies (231 patients) in which researchers compared intracranial pressure (ICP) monitoring and ultrasound measurement of optic nerve sheath diameter (ONSD) in consecutive adult patients with suspected elevated ICP. ONSD was measured 3 mm behind the globe; ICP and ONSD measurements were performed within 1 hour of each other.

The pooled sensitivity for ONSD detection of elevated ICP was 90% and the pooled specificity was 85%. The pooled diagnostic odds ratio was 51, meaning that patients with elevated ICP were 51 times more likely to have a positive ONSD test than those without elevated ICP.

Comment: With a 90% sensitivity for ruling out elevated intracranial pressure, bedside ultrasound measurement of optic nerve sheath diameter shows promise as a new tool to guide decision making, including prioritizing patients for diagnostic studies and determining whether computed tomography is needed before an unstable polytrauma patient is taken to the operating room.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine May 20, 2011

Citation(s): Dubourg J et al. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: A systematic review and meta-analysis. Intensive Care Med 2011 Apr 20; [e-pub ahead of print]. (http://dx.doi.org/10.1007/s00134-011-2224-2)

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【實際做法】
http://emj.bmj.com/content/26/9/630.full.pdf

外傷急救新觀念：術中血壓不必keep太高！

2011-05-06T18:58:00.000-07:00

Hypotensive Resuscitation in Trauma Patients Lessens Transfusion Needs
Also reduces incidence of postoperative coagulopathy and associated death.

The authors report an interim analysis of the first prospective randomized trial of intraoperative hypotensive resuscitation in patients. At a single level I trauma center, 90 patients with at least one episode of in-hospital systolic blood pressure ≤90 mm Hg who were undergoing laparotomy or thoracotomy for blunt (6 patients) or penetrating (84) trauma were randomized at entry to the operating room to have their mean arterial pressure (MAP) maintained at a target minimum of 50 mm Hg (low MAP) or 65 mm Hg (high MAP). Methods of achieving target levels were at the discretion of the anesthesiologist. MAPs that rose above the target were not lowered.

The low-MAP group received a significantly smaller amount of blood products (packed red blood cells, fresh frozen plasma, platelets) than the high-MAP group (1594 mL vs. 2898 mL) and had significantly lower mortality within 24 hours of admission to the intensive care unit (2.3% vs. 17.4%) and significantly lower mortality due to coagulopathy-associated postoperative hemorrhage (0 of 6 vs. 7 of 10). Mortality at 30 days did not differ significantly between the two groups (23% and 28%, respectively).

Comment: This interim analysis suggests that maintaining a low MAP during intraoperative resuscitation in seriously ill trauma patients is safe, reduces use of blood products, and decreases the incidence of postoperative coagulopathy and the related consequence of death. If these promising findings hold in the final analysis, similar approaches should be undertaken in the field and the emergency department.

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John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine May 6, 2011

Citation(s): Morrison CA et al. Hypotensive resuscitation strategy reduces transfusion requirements and severe postoperative coagulopathy in trauma patients with hemorrhagic shock: Preliminary results of a randomized controlled trial. J Trauma 2011 Mar; 70:652.

治敗血症休克用Levophed比Dopamine好

2011-04-22T19:10:00.000-07:00

Norepinephrine Outperforms Dopamine in Adults with Septic Shock
Use of norepinephrine was associated with a 9% reduction in mortality compared with dopamine.

According to the Surviving Sepsis Campaign guidelines, norepinephrine or its precursor, dopamine, are both recommended as first-line treatments to improve organ perfusion in patients with septic shock. To determine which vasopressor is better, researchers conducted a meta-analysis of six randomized trials that compared the two agents in patients with septic shock and that reported in-hospital or 28-day mortality.

The trials included a total of 995 patients randomized to norepinephrine and 1048 randomized to dopamine. Overall, mortality was significantly lower in the norepinephrine group than in the dopamine group (48% vs. 53%). Arrhythmias were significantly less common with norepinephrine than with dopamine (relative risk, 0.43).

Comment: This study suggests that norepinephrine is superior to dopamine for adult patients with refractory septic shock. The finding that dopamine is associated with more arrhythmias might explain the higher mortality, as arrhythmias can impair cardiac function, thereby leading to worse outcomes.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine April 22, 2011

Citation(s): Vasu TS et al. Norepinephrine or dopamine for septic shock: A systematic review of randomized clinical trials. J Intensive Care Med 2011 Mar 24; [e-pub ahead of print].
http://dx.doi.org/10.1177/0885066610396312

Midazolam plus Ketamine

2011-04-08T22:33:00.000-07:00

Adding Midazolam to Ketamine for Procedural Sedation Reduces Emergence Reactions in Adults

Coadministration significantly reduced incidence of emergence reactions, and route of ketamine administration had no effect on incidence of adverse events.

Ketamine is associated with untoward emergence reactions after procedural sedation, including nightmares and hallucinations. Coadministration of midazolam to mitigate this reaction is ineffective in children. Researchers assessed the effect of midazolam on incidence of ketamine emergence reactions and the effect of route of ketamine administration on incidence of adverse events in adult patients undergoing procedural sedation. In a prospective, double-blind, placebo-controlled study, 182 patients (age range, 18–50) at an academic emergency department in Turkey were randomized to receive ketamine either intravenously (1.5 mg/kg) or intramuscularly (4.0 mg/kg), either with or without intravenous midazolam (0.03 mg/kg).

Recovery agitation occurred significantly less frequently when midazolam was coadministered with ketamine (8% vs. 25%). Incidence of adverse events (recovery agitation, respiratory events, nausea and vomiting) was similar with the two routes of ketamine administration; no patient had respiratory compromise.

Comment: Coadministration of midazolam with ketamine in adults seems to mitigate emergence reactions with no significant downside.

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Richard D. Zane, MD, FAAEM

Published in Journal Watch Emergency Medicine April 8, 2011

CITATION(S): Sener S et al. Ketamine with and without midazolam for emergency department sedation in adults: A randomized controlled trial. Ann Emerg Med 2011 Feb; 57:109.e2.

硬幣卡食道不必每個都要插endo處理！

2011-04-05T06:12:00.000-07:00

Rapid Sequence Intubation for Esophageal Coin Removal in Kids
Rapid sequence intubation by emergency physicians resulted in coin removal in 95% of patients, but 10% of procedures lasted more than 30 minutes and half the patients had complications.

Esophageal coins pass spontaneously in children about 25% of the time, but most coins must be actively removed. Methods of removal in the emergency department (ED) include bougienage, Foley catheter, and Magill forceps. Endoscopy under general anesthesia typically is not performed in stable patients and, in stable patients, is delayed until patients have fasted and intubation can be performed in a more controlled setting than the ED. These authors report a 4-year retrospective review of 101 children (age range, 4 months–13 years) who underwent rapid sequence intubation (RSI; usually with succinylcholine and etomidate) for coin removal by emergency physicians at a pediatric ED in California.

Median time from ingestion to presentation was 5 hours. Coins were successfully retrieved in 96 patients, with Magill forceps alone (56 patients) or Magill forceps plus a Foley catheter (40 patients). Complications occurred in 46 patients and included minor bleeding (13 patients), lip lacerations (7), multiple attempts (5), hypoxia (2), accidental extubation (3), dental injuries (3), and bradycardia (2) despite pretreatment with atropine in 84 cases. Median ED length of stay was 5 hours (range, 1.5–45 hours), and median time from intubation to extubation was 15 minutes (range, 2–93 minutes); nine procedures lasted more than 30 minutes.

Comment:
Even at this tertiary referral center, almost 10% of procedures lasted longer than 30 minutes and nearly half the patients had complications. Faster, safer, simpler, less-expensive, and less resource-intensive techniques are more appropriate for removal of esophageal coins in most children. Why this aggressive RSI approach was used in the children in the study is unclear; however, it should be reserved for difficult cases and performed in an area of the hospital with dedicated resources.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine April 1, 2011

CITATION(S): Bhargava R and Brown L. Esophageal coin removal by emergency physicians: A continuous quality improvement project incorporating rapid sequence intubation. CJEM 2011 Jan; 13:28.

讓胸痛患者2小時內離開急診室？

2011-03-25T23:11:00.000-07:00

Highly Sensitive ED Protocol for Identifying Low-Risk Patients with Chest Pain
Implementation of a new accelerated diagnostic protocol could reduce emergency department length of stay and hospitalization rate.

Protocols to facilitate safe early discharge from the emergency department (ED) for low-risk patients with chest pain have limitations, including lack of validation and variable sensitivity. The prospective, observational, multinational Asia-Pacific Evaluation of Chest Pain Trial assessed a new, accelerated diagnostic protocol in consecutive adult ED patients who had at least 5 minutes of chest, neck, jaw, or arm pain or discomfort without obvious noncardiac cause and who did not have ST-segment-elevation myocardial infarction (STEMI).

The protocol included Thrombolysis In Myocardial Infarction (TIMI) score, electrocardiogram (ECG), and point-of-care biomarker testing (within 2 hours after arrival) for troponin I, creatine kinase MB, and myoglobin. Patients with TIMI scores of 0, no new ischemic changes on initial ECG, and normal biomarker panels were classified as low risk.

Among 3582 patients who completed 30-day follow-up, 421 (11.8%) had major adverse cardiac events within 30 days, most often non-STEMI (10.1%). Of 352 patients (9.8%) who were classified as low risk, 3 (0.9%) had major adverse cardiac events. The protocol had a sensitivity of 99.3% for identifying low-risk patients, a specificity of 11.0%, and a negative predictive value (NPV) of 99.1%. Had TIMI score not been included, NPV would have been 96.7%, and an additional 44 patients with major adverse cardiac events would have been missed.

Comment:
This study demonstrates that the combination of no new ischemic changes on initial ECG, normal point-of-care biomarker panel within 2 hours, and low pretest probability (TIMI score of 0) identifies patients who can safely be discharged from the ED. However, several issues about use of the protocol remain to be addressed, including performance relative to other protocols, whether use of laboratory biomarker testing improves accuracy, effect on patient care costs and hospital stay, and malpractice risk.

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John A. Marx, MD, FAAEMPublished in Journal Watch Emergency Medicine March 25, 2011

Citation(s): Than M et al. A 2-h diagnostic protocol to assess patients with chest pain symptoms in the Asia-Pacific region (ASPECT): A prospective observational validation study. Lancet 2011 Mar 26; 377:107.

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Background
Patients with chest pain contribute substantially to emergency department attendances, lengthy hospital stay, and inpatient admissions. A reliable, reproducible, and fast process to identify patients presenting with chest pain who have a low short-term risk of a major adverse cardiac event is needed to facilitate early discharge. We aimed to prospectively validate the safety of a predefined 2-h accelerated diagnostic protocol (ADP) to assess patients presenting to the emergency department with chest pain symptoms suggestive of acute coronary syndrome.

Methods
This observational study was undertaken in 14 emergency departments in nine countries in the Asia-Pacific region, in patients aged 18 years and older with at least 5 min of chest pain. The ADP included use of a structured pre-test probability scoring method (Thrombolysis in Myocardial Infarction [TIMI] score), electrocardiograph, and point-of-care biomarker panel of troponin, creatine kinase MB, and myoglobin. The primary endpoint was major adverse cardiac events within 30 days after initial presentation (including initial hospital attendance). This trial is registered with the Australia-New Zealand Clinical Trials Registry, number ACTRN12609000283279.

Findings
3582 consecutive patients were recruited and completed 30-day follow-up. 421 (11·8%) patients had a major adverse cardiac event. The ADP classified 352 (9·8%) patients as low risk and potentially suitable for early discharge. A major adverse cardiac event occurred in three (0·9%) of these patients, giving the ADP a sensitivity of 99·3% (95% CI 97·9—99·8), a negative predictive value of 99·1% (97·3—99·8), and a specificity of 11·0% (10·0—12·2).

Interpretation
This novel ADP identifies patients at very low risk of a short-term major adverse cardiac event who might be suitable for early discharge. Such an approach could be used to decrease the overall observation periods and admissions for chest pain. The components needed for the implementation of this strategy are widely available. The ADP has the potential to affect health-service delivery worldwide.

http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60310-3/abstract

斷層掃描會延誤剖腹手術的時機嗎？

2011-03-12T06:20:00.000-08:00

Abdominal Computed Tomography in Hypotensive Trauma Patients Delays Laparotomy and Increases Mortality

Authors urge caution in using this diagnostic tool for patients with blunt or penetrating trauma.

Computed tomography (CT) of the abdomen is being used increasingly in trauma patients, and, although it is highly accurate, its use in certain patients might delay definitive care, specifically laparotomy. To determine the risk that performing abdominal CT will delay laparotomy, researchers reviewed data from the National Trauma Data Bank from 2002 through 2006. Patients (age, above 14 years) with systolic blood pressure below 90 mm Hg on emergency department (ED) arrival and abdominal Abbreviated Injury Scale (AIS) score above 3 who underwent laparotomy within 90 minutes of ED arrival were included in the analysis. Patients transferred from other hospitals and those with significant brain injury (head AIS score above 3) were excluded.

Among 3218 patients, the median Injury Severity Score was 25, and the overall mortality rate was 32%; 446 patients (14%) underwent abdominal CT before laparotomy. The mortality rate was significantly higher in patients who underwent abdominal CT prior to laparotomy than in those who did not (44.8% vs. 29.5%). In logistic regression analysis, abdominal CT was independently associated with risk for death (odds ratio, 1.71), especially among patients who underwent laparotomy within 30 minutes after ED arrival (OR, 7.6).

Comment:
The authors did not assess the influence of ultrasound, diagnostic peritoneal lavage, or presence of pelvic fracture on surgical decision making. However, these findings reinforce that abdominal CT generally is not indicated for hypotensive patients with penetrating trauma or hypotensive patients with blunt trauma and a positive ultrasound or peritoneal lavage result and no pelvic fracture.

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John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine March 11, 2011

Citation(s): Neal MD et al. Over reliance on computed tomography imaging in patients with severe abdominal injury: Is the delay worth the risk? J Trauma 2011 Feb; 70:278.

20歲以下非心因性OHCA，要壓胸也要吹氣

2011-03-05T21:23:00.000-08:00

Compression-Only CPR Is Less Effective Than Conventional CPR in Some Patients
Among patients with out-of-hospital cardiac arrest in Japan, compression-only cardiopulmonary resuscitation was less effective than conventional CPR in patients younger than 20 with noncardiac causes of arrest.

Findings of several large studies led to guideline revisions recommending that untrained bystanders perform compression-only cardiopulmonary resuscitation (CPR) for adults with out-of-hospital cardiac arrest. Researchers in Japan analyzed a nationwide emergency medical services database to compare outcomes between patients with bystander-witnessed out-of-hospital cardiac arrest who received conventional CPR (19,328 patients) and those who received chest compression-only CPR (27,707 patients) during a 3-year period.

Rates of both overall 1-month survival and neurologically favorable 1-month survival were significantly higher in patients who received conventional CPR (adjusted odds ratio, 1.17 in each case). In analysis by age and cause of arrest, the benefit of conventional CPR was limited to patients younger than 20 with noncardiac causes. In analysis by time from arrest to start of CPR and cause of arrest, the benefit of conventional CPR over compression-only CPR increased with time to CPR among patients with noncardiac causes and among patients with all causes combined, but not among those with cardiac causes.

Comment:
This large study confirms that conventional CPR is the preferred technique for children, who have a higher proportion of noncardiac causes of arrest than adults. For adults, evidence supports compression-only CPR by bystanders. Outcomes in adults likely would be better with compression-only CPR by trained providers, too, but this is not yet proven; so guidelines continue to recommend conventional CPR by trained healthcare providers.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine March 4, 2011

Citation(s):
Ogawa T et al. Outcomes of chest compression only CPR versus conventional CPR conducted by lay people in patients with out of hospital cardiopulmonary arrest witnessed by bystanders: Nationwide population based observational study. BMJ 2011 Jan 27; 342:c7106. (http://dx.doi.org/10.1136/bmj.c7106)

抽血發現的甲狀腺功能低下〔TSH高〕，要不要治療？

2011-03-04T02:22:00.000-08:00

Raised TSH: to treat or not to treat?

Do you treat people with subclinical hypothyroidism?
You are supposed to, according to current guidelines.

The rationale for treating when serum thyroid stimulating hormone (TSH) is above 10 mIU/l is to alleviate mild symptoms, prevent progression to overt hypothyroidism, and lower cardiovascular risk.

Modest TSH elevations (below 7.0 mIU/l) may not warrant treatment. Large scale randomised clinical trials are needed to determine the effects of L-thyroxine treatment on coronary heart disease and related mortality in people who have subclinical hypothyroidism.

The current position seems to be that TSH levels above 10 mIU/l warrant treatment, levels of 7-10 mIU/l warrant consideration, while with levels below 7 mIU/l it may be justifiable to wait and see.

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Source: Evidence-Based Medicine 2011;16:31-32

H1N1 使用類固醇可能有害！

2011-02-18T21:11:00.000-08:00

Severe H1N1 Influenza Infection: Hold the Corticosteroids!

An observational European study shows that corticosteroids increased risk for pneumonia and conferred no mortality benefit in patients with severe H1N1 infection.

Use of corticosteroids to mitigate the cytokine storm that might contribute to poor outcomes in otherwise healthy people with pandemic H1N1 influenza infection is controversial, even in those with acute respiratory distress syndrome (ARDS). In a prospective observational study, investigators evaluated the effect of corticosteroids on outcomes in 220 intensive care unit (ICU) patients who were enrolled in the European Society of Intensive Care Medicine H1N1 registry from June 2009 through February 2010. H1N1 influenza A infection was confirmed in 194 patients, probable in 2, and suspected in 24. All patients received antivirals, and 78% were mechanically ventilated.

The 126 patients (57%) who received corticosteroids on ICU admission (dosages equivalent to >24 mg/day of methylprednisone or >30 mg/day of prednisone), compared to patients who did not, were significantly older, more likely to have comorbid pulmonary conditions, and more likely to be chronic corticosteroid users. Although patients who received corticosteroids on ICU admission were significantly more likely to contract hospital-acquired pneumonia (26% vs. 14%; odds ratio, 2.2) and to die in the ICU (46% vs. 18%; OR, 3.8), the association with mortality was no longer present after adjustment for severity of disease and other confounding variables (age, asthma, chronic obstructive pulmonary disease, chronic corticosteroid use). Results were similar when the analysis was limited to the 74% of patients with ARDS.

Comment: This study is limited by its observational nature, variable dosing of oseltamivir, and that patients who received "rescue" corticosteroids after ICU admission were not considered part of the corticosteroid group. For now, corticosteroids do not seem helpful - and might be harmful - in patients with H1N1 influenza.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine February 18, 2011

Citation(s): Martin-Loeches I et al. Use of early corticosteroid therapy on ICU admission in patients affected by severe pandemic (H1N1)v influenza A infection. Intensive Care Med 2011 Feb; 37:272.

高壓氧治療CO中毒，效果沒想像中好？！

2011-01-28T19:20:00.000-08:00

Is Hyperbaric Oxygen Therapy Beneficial in Carbon Monoxide Poisoning?
HBO therapy did not add benefit to normobaric oxygen therapy in these studies.

In two parallel prospective randomized studies, researchers evaluated the effectiveness of hyperbaric oxygen therapy (HBOT) in patients (age, ≥15 years) with acute isolated carbon monoxide (CO) poisoning who presented to an academic hospital in France between 1989 and 2000. In trial A (mild poisoning), 179 patients with transient loss of consciousness received normobaric oxygen therapy (NBOT) for 6 hours or NBOT for 4 hours plus one session of HBOT. In trial B (severe poisoning), 206 comatose patients (Glasgow Coma Scale score below 8) received NBOT for 4 hours plus either one or two HBOT sessions. Each HBOT session lasted 2 hours in a multiplace chamber at 2.0 atmospheres absolute; interval between sessions was 6 to 12 hours. At baseline, 82% of patients in trial A and 65% in trial B had headaches, and 4% and 10%, respectively, had seizures.

At 1 month, patients completed a symptom questionnaire and were evaluated by an intensivist with neurology training who was blinded to treatment group. Complete recovery was defined as absence of patient-reported symptoms and normal physical and neuropsychological exam, "moderate sequelae" was defined as one or more self-reported symptoms, and "severe sequelae" was defined as any objective physical exam finding. In trial A, complete recovery rates were similar in the two groups (approximately 60%), and no patient in either group had severe sequelae. In trial B, complete recovery rates were significantly lower in the group that received two HBOT sessions than in the group that received one session (47% vs. 68%; unadjusted odds ratio, 0.42).

Comment:
The trial A findings support the teaching that most patients with mild CO poisoning will improve after removal from the exposure and treatment with high-flow oxygen. The trial B finding is surprising and suggests that HBOT might not benefit even those patients with severe toxicity. Pending a larger trial with clearer toxicity definitions, physicians should contact a regional poison center or HBOT referral center to discuss with consultants the best approach for an individual patient with known CO poisoning, particularly when the treatment might involve transfer of an unstable patient.

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Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine January 28, 2011

Citation(s):
Annane D et al. Hyperbaric oxygen therapy for acute domestic carbon monoxide poisoning: Two randomized controlled trials. Intensive Care Med 2010 Dec 2; [e-pub ahead of print]. (http://dx.doi.org/10.1007/s00134-010-2093-0)

小兒急救 - 新版的指引

2011-01-25T19:56:00.000-08:00

Updated Recommendations for Pediatric Resuscitation

The 2010 International Liaison Committee on Resuscitation Pediatric Task Force has updated the 2005 treatment recommendations for pediatric resuscitation. Highlights include the following:

Initiate cardiopulmonary resuscitation (CPR) if there are no signs of life and a pulse is not palpated within 10 seconds.
Provide conventional CPR (chest compressions with rescue breathing).
Compress at least one third of the anterior-posterior dimension of the chest.
Consider using cuffed tracheal tubes in infants and young children; cuff pressure should not exceed 25 cm H2O. Appropriate sized tubes by age are as follows:
# 3 mm for age ≤1 year
# 3.5 mm for age 1–2 years
# Age in years/4 + 3.5 mm for age >2 years
Modify or discontinue cricoid pressure if it impedes preintubation ventilation or intubation.
Monitor capnography to confirm endotracheal tube position, recognizing that end-tidal CO2 in infants and children might be below detectable limits for colorimetric devices (85% sensitivity and 100% specificity).
Consider use of an esophageal detector device in children weighing >20 kg.
Use capnography monitoring to assess effectiveness of chest compressions.
Avoid excessive ventilation, which can decrease cerebral perfusion pressure, rates of return of spontaneous circulation (ROSC), and survival rates.
After ROSC, titrate oxygen concentration to limit the risk for toxic oxygen byproducts.
For pediatric septic shock, include therapy directed at normalizing central venous oxygen saturation to ≥70%.
Do not routinely use bicarbonate or calcium for pediatric cardiac arrest: Both agents are associated with decreased survival.

Comment:
These consensus recommendations are based on a thorough evaluation of the literature, and emergency physicians should know them.

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Katherine Bakes, MD
Published in Journal Watch Emergency Medicine January 21, 2011

Citation(s): Kleinman ME et al. Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Pediatrics 2010 Nov; 126:e1261.

國內再度出現百日咳死亡個案

2011-01-23T20:47:00.000-08:00

國內再度出現百日咳死亡個案，家有嬰幼兒的民眾請小心防範

行政院衛生署疾病管制局公布一例新生兒百日咳死亡個案，該個案為去（99）年底出生之女嬰，出生後於接生之婦產科接受照護10天後返家，當日出現輕微咳嗽，赴某兒科診所診斷疑似感冒，本年1月5日因發燒、咳嗽有痰、發紺、嘔吐等症狀轉診至某醫學中心隔離治療，1月10日通報，2日後因敗血性休克死亡，經該局檢驗確認並研判死因與百日咳相關。經調查個案之母於生產前數天即有咳嗽症狀並就醫治療，防疫人員已對個案雙親及婦產科診所之醫護人員等密切接觸者進行採檢及預防性投藥，並實施健康監視中，目前尚無新增疑似個案。近期同時另有一起新生兒病例，個案目前仍住院治療，病情穩定恢復中，該局提醒家有嬰幼兒的民眾應注意防範。

百日咳為百日咳桿菌所引起之急性呼吸道傳染病，主要是經由飛沫傳染，臨床症狀為咳嗽持續至少兩週，且伴隨陣發性咳嗽、吸入性哮聲或咳嗽後嘔吐等。常發生於5歲以下兒童，其他年齡層亦可能發生，但症狀較輕微或不明顯。依據該局監視資料顯示，近年國內百日咳個案每年約在40至90例間，以未完成接種疫苗的嬰幼兒為主要感染族群，最近一起死亡個案發生於92年，為出生一個月的男嬰，近年來青少年個案的比率有上升趨勢，澳洲及美國等先進國家之疫情亦十分嚴重。

接種疫苗可有效預防百日咳，現行預防接種政策為出生滿2,4,6,18個月及國小一年級各接種一劑百日咳相關疫苗，家中有嬰幼兒的民眾，請務必按時攜帶嬰幼兒前往接種，以獲得足夠的保護力。此外，在普遍施打疫苗的環境下，百日咳常經由成人或較年長孩童傳播，民眾務必注意自身及其他較年長孩童的衛生，尤其自外返家，在接觸嬰幼兒前，應先更衣洗手，以免將細菌傳染給幼兒，並儘量避免帶嬰幼兒出入人潮擁擠、空氣不流通之公共場所，或到醫院探病，以降低感染機會。如發現自身或家人出現疑似症狀，應立即就醫、配戴口罩，並按醫囑確實完成治療，勿任意停藥，且務必配合衛生機關進行防治措施，以防杜疾病傳播。

由於小於6個月的寶寶是感染百日咳的高危險族群，主要的感染源為親密照顧的媽媽及其他照顧者。各國亦陸續建議未曾接種百日咳疫苗的育齡婦女，應接種一劑適用於成人的減量破傷風白喉非細胞性百日咳混合疫苗（Tdap），以預防感染百日咳傳染幼兒。而之前未曾接種 Tdap之產婦，則應於產後離開醫院前完成接種。而因醫療照護人員及產後護理機構之醫療照護者為除母親及親密照顧的親人外，與新生寶寶最親密接觸者，為預防該等人員感染百日咳傳染新生幼兒，針對該等機構之各相關單位照護人員，建議接種一劑Tdap，以避免百日咳之發生，危及新生兒健康，同時提升國內照護品質。

疫情資訊請查詢：
http://www.cdc.gov.tw/mp.asp?mp=1

中耳炎還是用抗生素比較好〔？〕

2011-01-13T05:59:00.000-08:00

What is the most effective treatment for acute otitis media?
Amoxicillin–clavulanate has been shown to be the most effective treatment for acute otitis media.

As compared to placebo treatment, what were the benefits of antibiotic treatment for children 6 to 23 months of age with acute otitis media in this clinical trial?
Children who were treated with amoxicillin–clavulanate, as compared with those who received placebo, had consistently more favorable short-term outcomes, including a sustained symptomatic response, an absence of otoscopic evidence of persistent middle-ear infection, and a reduced rate of residual middle-ear effusion.

As compared to placebo treatment, was speed of resolution different for children who received antibiotic treatment in this study?
Yes, among the children who received amoxicillin–clavulanate, 35% had initial resolution of symptoms by day 2, 61% by day 4, and 80% by day 7; among children who received placebo, 28% had initial resolution of symptoms by day 2, 54% by day 4, and 74% by day 7.

As compared to placebo-treated children, what adverse effects were significantly more common among children with acute otitis media who received antibiotic treatment?
Dermatitis in the diaper area and protocol-defined diarrhea occurred commonly, and often together, among children receiving antimicrobial agents. Both protocol-defined diarrhea and diaper area dermatitis occurred significantly more frequently among children who received amoxicillin–clavulanate than those that received placebo.

---

NEJM

急診的CVP不會比ICU容易感染

2011-01-07T20:56:00.000-08:00

Are Central Lines Placed in the ED Associated with Higher Risk for Bloodstream Infections?
The rate of bloodstream infections for central lines placed in a single emergency department was comparable to the rate for lines placed in the intensive care unit.

On January 1, 2010, The Joint Commission added to its quality measures a National Patient Safety Goal for use of maximum barrier precautions and a checklist and standardized protocol for placement of central venous catheters throughout the hospital, including in the emergency department (ED). In a retrospective chart review, researchers determined the rate of central line–associated bloodstream infections (CLABSIs) in a single urban academic ED in Boston before implementation of the checklist.

During 2007 and 2008, 656 patients underwent placement of central lines in the ED and 7 CLABSIs were reported. The CLABSI rate for lines placed in the ED was 1.93 per 1000 catheter-days. The CLABSI rate for lines placed in the hospital's ICU during 2008 was 1.51 per 1000 catheter-days, and the nationally reported rate for ICU-placed central lines was 2.05 per 1000 catheter-days.

Comment:
Central lines placed in the ED are perceived as being more prone to infection than those placed in the ICU for myriad reasons, particularly the urgency with which such lines often are placed. However, in this single-hospital study, CLABSI rates were similar for lines placed in the ED and the ICU.

—
Richard D. Zane, MD, FAAEM
Published in Journal Watch Emergency Medicine January 7, 2011

Citation(s): LeMaster CH et al. Infection and natural history of emergency department–placed central venous catheters. Ann Emerg Med 2010 Nov; 56:492.

院內CPR最好能有「葉醫師」幫忙

2010-12-31T18:03:00.000-08:00

ECMO May Improve In-Hospital Cardiac Arrest Outcomes
Cardiopulmonary resuscitation using extracorporeal membrane oxygenation improved survival compared with conventional CPR alone.

Indications for using extracorporeal membrane oxygenation (ECMO) to augment cardiopulmonary resuscitation (E-CPR) are ill-defined. Researchers retrospectively analyzed outcomes in 406 patients aged 18 to 80 with witnessed in-hospital cardiac arrest who underwent CPR for at least 10 minutes in a single hospital in Korea during a 6-year period. Patients with poor baseline neurologic status, acute intracranial hemorrhage, terminal cancer, traumatic hemorrhagic shock, irreversible organ failure, or sepsis were excluded.

Resuscitation team leaders made the decision to initiate ECMO (available within 5–10 minutes during the day and 10–20 minutes at night). In most cases, E-CPR was initiated in patients with known severe left ventricular dysfunction, prolonged arrest (no return of spontaneous circulation after 10–20 minutes), or recurrent arrest. E-CPR was established in 80 of 85 patients in whom it was attempted, and conventional CPR alone was performed in 321 patients.

Using propensity score analysis, the authors calculated that the E-CPR group had significantly higher rates of survival to hospital discharge with minimal neurologic impairment (odds ratio for mortality or neurologic deficit, 0.17) and survival to 6 months with minimal neurologic impairment (hazard ratio for neurologic impairment, 0.48) than patients in the conventional CPR group. Results were similar in the subgroup of patients with arrest from cardiac origin.

Comment: Although ECMO is not available within minutes in all hospitals, it seems to provide significant benefit to patients with poor left ventricular function or prolonged or recurrent arrest. Pending a randomized trial, it is reasonable to consider using ECMO in such patients.

—
Kristi L. Koenig, MD, FACEP

Published in Journal Watch Emergency Medicine December 29, 2010
Citation(s): Shin TG et al. Extracorporeal cardiopulmonary resuscitation in patients with inhospital cardiac arrest: A comparison with conventional cardiopulmonary resuscitation. Crit Care Med 2011 Jan; 39:1.

ICU 血糖之控制指標

2010-12-22T19:23:00.000-08:00

Q: At what threshold of serum glucose should insulin therapy be initiated among patients requiring intensive care?
A: Pending more data to guide the identification of optimal glucose levels, national associations recommend that insulin therapy be initiated once glucose exceeds a threshold of 180 mg per deciliter.

Q: According to most professional guidelines, what should the target serum glucose be among intensive care patients receiving insulin therapy?
A: Most professional societies recommend a target glucose level of 140 to 180 mg per deciliter for patients requiring intensive care, with the use of an established, preferably computerized insulin-infusion algorithm and close monitoring of glucose levels.

Source: NEJM Teaching Topic Dec 23, 2010 - Glycemic Control in the ICU

Etomidate可使用於敗血症

2010-12-17T20:40:00.000-08:00

Etomidate or Midazolam for Rapid Sequence Induction in Patients with Suspected Sepsis?
Outcomes did not differ significantly with the two induction agents.

Despite studies showing no increase in adverse outcomes related to etomidate induction for intubation of patients with shock (JW Emerg Med Jul 2 2009 and JW Emerg Med Feb 13 2009), some clinicians still oppose its use in such patients. In this prospective, double-blind, randomized trial, 122 adult patients who presented to a single emergency department with suspected sepsis and indication for intubation received either midazolam (0.1 mg/kg) or etomidate (0.3 mg/kg) for induction. Sepsis was confirmed in 96 patients who had clear evidence of infection and fulfilled two of four criteria for systemic inflammatory response syndrome.

The midazolam and etomidate groups demonstrated no significant differences in median hospital length of stay (LOS) (9.5 and 7.3 days), median intensive care unit LOS (4.2 and 3.1 days), median ventilator days (2.8 and 2.1 days), or inhospital mortality (21% and 26%). Subgroup analysis of patients who survived to discharge also showed no difference in median hospital LOS between midazolam and etomidate recipients (11.3 and 11.8 days).

Comment: In this study, use of a single bolus of etomidate for induction in patients with sepsis was not associated with any deleterious outcomes. Etomidate is an ideal induction agent because of its predictable dosing, rapid onset, short duration of action, and excellent hemodynamic stability. This report adds to a growing body of well-designed studies that refute the assertion that etomidate should not be used in patients with sepsis.

—
Richard D. Zane, MD, FAAEM
Published in Journal Watch Emergency Medicine December 17, 2010

Citation(s): Tekwani KL et al. A comparison of the effects of etomidate and midazolam on hospital length of stay in patients with suspected sepsis: A prospective, randomized study. Ann Emerg Med 2010 Nov; 56:481.

小兒脊椎穿刺〔LP〕的最佳身體擺放位置

2010-12-16T07:02:00.000-08:00

Positioning for Lumbar Puncture in Children Evaluated by Bedside Ultrasound

BACKGROUND
Lumbar punctures are commonly performed in the pediatric emergency department. There is no standard, recommended, optimal position for children who are undergoing the procedure.

OBJECTIVE
To determine a position for lumbar punctures where the interspinous space is maximized, as measured by bedside ultrasound.

METHODS
A prospective convenience sample of children under age 12 was performed. Using a portable ultrasound device, the L3-L4 or L4-L5 interspinous space was measured with the subject in 5 different positions. The primary outcome was the interspinous distance between 2 adjacent vertebrae. The interspinous space was measured with the subject sitting with and without hip flexion. In the lateral recumbent position, the interspinous space was measured with the hips in a neutral position as well as in flexion, both with and without neck flexion. Data were analyzed by comparing pairwise differences.

RESULTS
There were 28 subjects enrolled (13 girls and 15 boys) at a median age of 5 years. The sitting-flexed position provided a significantly increased interspinous space. Flexion of the hips increased the interspinous space in both the sitting and lateral recumbent positions. Flexion of the neck, did not significantly change the interspinous space.

CONCLUSIONS
The interspinous space of the lumbar spine was maximally increased with children in the sitting position with flexed hips; therefore we recommend this position for lumbar punctures. In the lateral recumbent position, neck flexion does not increase the interspinous space and may increase morbidity; therefore, it is recommended to hold patients at the level of the shoulders as to avoid neck flexion.

http://pediatrics.aappublications.org/cgi/content/abstract/125/5/e1149

兒童鼻噴劑 Fentanyl 可有效止痛

2010-12-10T18:54:00.000-08:00

Intranasal Fentanyl for Pediatric Fracture Pain
Children treated with intranasal fentanyl had statistically significant reductions in pain scores.

Researchers prospectively evaluated the analgesic efficacy of atomized intranasal fentanyl (2 µg/kg; maximum dose, 100 µg) in 81 children (mean age, 8 years) who presented with clinically suspected fractures to a pediatric emergency department in Wisconsin. Eligible patients had moderate-to-severe pain according to scores on the Wong Baker Faces Scale (WBS) for children ages 3 to 8 years and a 100-mm visual analog scale (VAS) for children ages 9 to 18 years. The primary outcome measure was change in pain score at 10, 20, and 30 minutes. A significant response was defined as a decrease of one face on the WBS or 13 mm on the VAS.

Among 53 children ages 3 to 8 years, median WBS pain scores decreased significantly from five faces at baseline to three at 10 minutes and two at 20 and 30 minutes; 74% and 87% of patients, respectively, achieved clinically significant pain reduction at 10 and 30 minutes. Among 28 children ages 9 to 18 years, mean VAS pain scores decreased significantly (by 21–27 mm) at each time point, from a mean score of 70 mm at baseline; 69% and 61% of patients, respectively, achieved clinically significant pain reduction at 10 and 30 minutes.

Comment:
Intranasal fentanyl is rapid and effective and avoids venipuncture. As with all opioid analgesia, additional doses might be required to reach the desired endpoint.

—
Katherine Bakes, MD
Published in Journal Watch Emergency Medicine December 10, 2010

Citation(s): Saunders M et al. Use of intranasal fentanyl for the relief of pediatric orthopedic trauma pain. Acad Emerg Med 2010 Nov; 17:1155.

終於有各大醫學會出來背書該如何併用Plavix和PPI了

2010-12-10T05:13:00.000-08:00

Consensus Document on Concomitant Use of Clopidogrel and PPIs
Proton-pump inhibitors are endorsed for clopidogrel patients at high risk for gastrointestinal bleeding.

To address the somewhat confusing literature on the interaction between proton-pump inhibitors (PPIs) and clopidogrel, a new "consensus document" has been published jointly by the American College of Cardiology, American College of Gastroenterology, and American Heart Association.

Clopidogrel is converted to its active form by the hepatic enzyme CYP2C19, which is competitively inhibited by PPIs. Although platelet function studies have shown that PPI use lessens clopidogrel-mediated inhibition of platelet aggregation, the clinical relevance of this observation has been debated.

The consensus writers make the following points:

Some, but not all, observational studies have shown small statistically significant higher risk for adverse cardiovascular events among patients who received PPIs and clopidogrel concomitantly (compared with clopidogrel alone). However, in the only large randomized trial (the recently published COGENT study; JW Cardiol Oct 6 2010), patients who received omeprazole plus clopidogrel had similar rates of adverse cardiovascular events and lower rates of adverse gastrointestinal (GI) events than recipients of clopidogrel alone.
In patients with histories of upper GI bleeding and those at high risk for this complication (e.g., advanced age; concomitant use of warfarin, steroids, or nonsteroidal anti-inflammatory drugs; Helicobacter pylori infection), the benefits of PPI therapy probably outweigh the very small risk that PPI therapy will interfere with clopidogrel's efficacy.
Patients at low risk for GI bleeding who require clopidogrel therapy should not receive concomitant PPIs.

Comment:
This document will disappoint readers who expect an unambiguous algorithm that is easily applied to all patients. Nevertheless, by endorsing use of PPIs for clopidogrel-treated patients at high risk for upper GI bleeding, the authors provide validation for this widespread practice.

—
Allan S. Brett, MD
Published in Journal Watch General Medicine December 9, 2010

Citation(s): Abraham NS et al. ACCF/ACG/AHA 2010 expert consensus document on the concomitant use of proton pump inhibitors and thienopyridines: A focused update of the ACCF/ACG/AHA 2008 expert consensus document on reducing the gastrointestinal risks of antiplatelet therapy and NSAID use. J Am Coll Cardiol 2010 Dec 7; 56:2051. (http://dx.doi.org/10.1016/j.jacc.2010.09.010)

Ketamine引起的喉頭痙攣

2010-11-27T22:37:00.000-08:00

Ketamine-Associated Pediatric Laryngospasm
Clinical variables fail to predict pediatric ketamine-associated laryngospasm.

結論：
(1) Ketamine引起的喉頭痙攣很罕見。
(2) Ketamine引起的喉頭痙攣是無法預測的。
(3) Ketamine引起的喉頭痙攣是無法以BZD併用來預防的。

In a 2009 meta-analysis of 8282 children undergoing ketamine sedation in the emergency department, investigators identified risk factors for airway and respiratory adverse events, including 22 occurrences (0.3%) of laryngospasm, defined as "stridor or other evidence of airway obstruction that did not improve with airway alignment maneuvers" (Ann Emerg Med 2009; 54:158). Now, the investigators performed a case-control analysis on the same dataset to assess predictors of ketamine-associated laryngospasm.

Each of the 22 case patients (median age, 3.7 years) was matched to 4 controls by American Society of Anesthesiologists (ASA) physical status ≥3 vs. <3, oropharyngeal procedure, ketamine dose, route of ketamine administration (intravenous vs. intramuscular), coadministration of anticholinergic agents, and coadministration of benzodiazepines (individual variables were excluded from matching when the variable was tested as a predictor). In univariate and multivariate analysis, the investigators evaluated the association between laryngospasm and each of seven variables: age, dose, oropharyngeal procedure, underlying physical illness, route of ketamine administration, coadministration of anticholinergics, and coadministration of benzodiazepines.

Benzodiazepine coadministration was the only variable that was significantly associated with laryngospasm and only in the multivariate analysis (odds ratio, 13.7). The number needed to treat with ketamine plus benzodiazepines to result in 1 occurrence of laryngospasm was 26. The authors question the validity of an association between benzodiazepine coadministration and laryngospasm, given the lack of statistical significance in the univariate analysis or in their previous regression analyses.

Comment: This study shows that ketamine-associated laryngospasm is rare and unpredictable. Although data on the association between benzodiazepine coadministration and laryngospasm are mixed, given the potential risk and the absence of evidence of benefit, routine coadministration should be avoided.

—
Katherine Bakes, MD
Published in Journal Watch Emergency Medicine November 24, 2010

Citation(s): Green SM et al. Laryngospasm during emergency department ketamine sedation: A case-control study. Pediatr Emerg Care 2010 Nov; 26:798.

補充維他命B可以防呆嗎？

2010-11-11T21:14:00.000-08:00

Vitamin B Supplementation and Cognition
In older men, supplementation did not affect cognition.

Because high plasma homocysteine levels are associated with cognitive impairment in epidemiologic studies, in multiple clinical trials researchers have examined whether vitamin B supplementation — which lowers homocysteine levels — improves cognition or delays onset of cognitive impairment in older adults; results have been mostly negative. In a new study, Australian researchers randomized 299 community-dwelling hypertensive men (age, above 75) without dementia to receive either placebo or a combination of vitamin B6, vitamin B12, and folic acid.

During 2 years of treatment, no differences between groups were noted on several measures of cognition. Even in subgroups in which benefit seemed likely — men with high baseline homocysteine levels (above 15 mcmol/L) and men with mild cognitive impairment at baseline — the investigators found no benefit from vitamin B supplementation.

Comment: This study adds to a growing body of evidence that vitamin B supplementation does not favorably affect cognition in older adults. One possible inference is that homocysteine is a marker — not a cause — of cognitive impairment in older adults.

—
Allan S. Brett, MD
Published in Journal Watch General Medicine November 10, 2010

Citation(s): Ford AH et al. Vitamins B12, B6, and folic acid for cognition in older men. Neurology 2010 Oct 26; 75:1540. (http://dx.doi.org/10.1212/WNL.0b013e3181f962c4)

SAH 的重要臨床特徵

2010-11-09T20:07:00.000-08:00

Clinical Decision Rules to Identify Patients at High Risk for Subarachnoid Hemorrhage
One of three rules might eliminate unnecessary evaluation of patients with acute headache.

Because subarachnoid hemorrhage (SAH) is a potentially devastating cause of acute headache, many patients with acute headache undergo extensive testing (e.g., computed tomography [CT], lumbar puncture) to rule it out. In this 5-year multicenter prospective Canadian study that involved nearly 2000 neurologically intact adults who presented with acute (peaking within 1 hour) nontraumatic headache, investigators sought to identify clinical characteristics that predicted SAH.

Overall, 130 patients had SAH. Sixteen clinical characteristics were associated significantly with SAH and were used to create three possible clinical decision rules:

Rule 1: age >40, complaint of neck pain or stiffness, witnessed loss of consciousness, onset of headache with exertion.
Rule 2: arrival by ambulance, age >45, vomiting at least once, diastolic blood pressure >100 mm Hg.
Rule 3: arrival by ambulance, systolic blood pressure >160 mm Hg, complaint of neck pain or stiffness, age 45–55.

For each rule, patients are investigated for SAH if one or more clinical characteristics in the rule are present. Retrospectively, each of the three rules had 100% sensitivity, and their specificities were between 28% and 39%.

Comment:
Although these decision rules are promising, they must be validated in other populations before they are used routinely; indeed, the authors note that a prospective validation study is under way. But, in the meantime, the findings provide guidance: Patients who present with nontraumatic headaches that peak within 1 hour and who have any of the clinical characteristics mentioned in the rules above should be assessed carefully for SAH. As the authors note, validated rules "could allow clinicians to be more selective and accurate when investigating patients with headache" and lower use of CT and lumbar puncture.

—
Paul S. Mueller, MD, MPH, FACP

Published in Journal Watch General Medicine November 9, 2010
Citation(s): Perry JJ et al. High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: Prospective cohort study. BMJ 2010 Oct 28; 341:c5204. (http://dx.doi.org/10.1136/bmj.c5204)

Head trauma: 到院前不給高張溶液

2010-11-05T22:44:00.000-07:00

Prehospital Hypertonic Fluid Fails to Improve Outcomes in Patients with Blunt Head Trauma
In the largest randomized controlled trial to date, prehospital hypertonic fluid therapy did not improve neurological outcomes in patients with severe blunt head trauma without hypovolemic shock.

Hypertonic fluid therapy diminishes cerebral edema and enhances systemic perfusion pressure in patients with severe blunt head injury, but its effect on neurological outcome is unknown. In a multicenter, double-blind, randomized, placebo-controlled trial, researchers evaluated the effect of hypertonic fluid in patients >15 years who had sustained severe blunt closed head injury (prehospital Glasgow Coma Scale score <8) and did not have hypovolemic shock (systolic blood pressure ≤70 mm Hg or 71–90 mm Hg with a pulse ≥108 beats per minute). Patients were randomized to receive an initial fluid bolus of 250 mL of 7.5% saline, 7.5% saline/6% dextran 70, or 0.9% saline within 4 hours of the dispatch call.

Six-month outcome data were available for 1087 of 1282 patients (85%) who were enrolled from 2006 to 2009. At 6 months, there were no significant differences between the hypertonic-fluid groups and the normal-saline group in neurological outcome (as measured by the Extended Glasgow Outcome Scale and Disability Rating Scale), survival at 28 days, survival at hospital discharge, development of organ failure, or length of stay in an intensive care unit or hospital. No increase in progression of intracranial hemorrhage was noted in the hypertonic-fluid groups.

Comment:
Although this study is the largest of its kind, the authors did not control for postintervention neurosurgical management or fluid administration (including additional hypertonic saline or mannitol), and 15% of patients were lost to follow-up. Currently, hypertonic saline is not recommended for prehospital treatment of patients with severe head injury. This trial should not lead to a change in practice.

—
John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine November 5, 2010

Citation(s): Bulger EM et al. Out-of-hospital hypertonic resuscitation following severe traumatic brain injury: A randomized controlled trial. JAMA 2010 Oct 6; 304:1455.

為何偏好洗血管不洗腹膜？

2010-10-26T21:50:00.000-07:00

Hemodialysis vs. Peritoneal Dialysis
Outcomes are comparable, but few patients chose peritoneal dialysis.

Patients with end-stage renal disease (ESRD) have better outcomes with kidney transplant than with dialysis. However, about 100,000 ESRD patients start dialysis annually because of limited donor organs or contraindications to transplantation; about 7% start with peritoneal dialysis (PD). In two U.S. studies, researchers address outcomes of and preferences for PD and hemodialysis (HD).

In one study, 685,000 HD and PD patients were assessed in 3-year cohorts from 1996 to 2004; mortality at 5 years of follow-up was evaluated. Compared with HD patients, PD patients were younger, healthier, and more likely to be white. In analyses adjusted for these factors, PD patients had somewhat higher risk for death (about 8% higher) than HD patients between 1996 and 2001, but no difference was noted from 2002 to 2004. The analyses also were adjusted for the greater likelihood that PD patients are selected for transplant. Median survival after dialysis initiation was 36.6 months for PD patients and 38.4 months for HD patients.

In another study, about 1600 ESRD patients were surveyed from 2005 to 2007; nearly 1000 (61%) were counseled about PD, of whom 108 (11%) started PD. Of the 631 patients who did not receive PD counseling, only 10 (1.6%) started PD. Patients who chose PD were younger, healthier, and more likely to be employed. In analyses controlled for demographic and clinical factors, rates of PD use varied substantially across major dialysis centers.

Comment:
Outcomes with PD are similar to those with HD, and PD costs about US$20,000 less annually, yet — strikingly — a substantial proportion of patients do not receive counseling about PD. An editorialist notes that nephrologists report decreasing experience with PD and, therefore, are increasingly uncomfortable counseling patients about it, which leads to a downward spiral of counseling and use. A new Medicare benefit that provides for six sessions of counseling about dialysis options could help reverse this trend.

—
Thomas L. Schwenk, MD
Published in Journal Watch General Medicine October 26, 2010

Citation(s):
Mehrotra R et al. Similar outcomes with hemodialysis and peritoneal dialysis in patients with end-stage renal disease. Arch Intern Med 2010 Sep 27; [e-pub ahead of print]. (http://dx.doi.org/10.1001/archinternmed.2010.352)
Kutner NG et al. Patient awareness and initiation of peritoneal dialysis. Arch Intern Med 2010 Sep 27; [e-pub ahead of print]. (http://dx.doi.org/10.1001/archinternmed.2010.361)
Johansen KL. Choice of dialysis modality in the United States. Arch Intern Med 2010 Sep 27; [e-pub ahead of print]. (http://dx.doi.org/10.1001/archinternmed.2010.370)

植物為主食者比較長壽

2010-10-12T21:44:00.000-07:00

Low-Carbohydrate Diets (Plant- vs. Animal-Based) and Mortality
Plant-based low-carb diets were associated with lower all-cause and cardiovascular mortality.

Recent studies have shown equivalence of low-carbohydrate and low-fat diets for weight loss (JW Gen Med Aug 19 2010). In this large prospective study, researchers assessed whether type of low-carb diet — plant-based or animal-based — affects length of life. They used self-reported diet histories gathered during 20-plus years of follow-up in the observational Nurses' Health Study (85,000 women) and the Health Professionals Follow-up Study (44,000 men) to determine whether participants reported a low-carb diet pattern.

The researchers calculated a vegetable low-carbohydrate score for each participant: Compared with those in the lowest decile of vegetable protein and fat intake, those in the highest decile had lower all-cause mortality (hazard ratio, 0.80) and cardiovascular mortality (HR, 0.77) — but not lower cancer mortality (HR, 0.96). Similarly, animal low-carbohydrate scores were calculated: Compared with those in the lowest decile of animal protein and fat intake, those in the highest decile had greater overall mortality (HR, 1.23), cardiovascular mortality (HR, 1.14), and cancer mortality (HR, 1.28). Analyses were adjusted for multiple confounders.

Comment:
This large prospective study suggests that not all low-carbohydrate diets are equal when considering length of life — plant-based diets appear to be superior to animal-based ones. Nonetheless, editorialists remind us of the potential hazards involved in attributing causation using data from observational studies.

—
Jamaluddin Moloo, MD, MPH
Published in Journal Watch General Medicine October 12, 2010

Citation(s):
Fung TT et al. Low-carbohydrate diets and all-cause and cause-specific mortality: Two cohort studies. Ann Intern Med 2010 Sep 7; 153:289. (http://www.annals.org/content/153/5/289.abstract)
Yancy WS Jr et al. Animal, vegetable, or . . . clinical trial? Ann Intern Med 2010 Sep 7; 153:337. (http://www.annals.org/content/153/5/337.extract)

BMJ也打破葡萄糖胺有效治療退化性關節炎的「神話」

2010-09-23T18:03:00.000-07:00

Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis

Objective
To determine the effect of glucosamine, chondroitin, or the two in combination on joint pain and on radiological progression of disease in osteoarthritis of the hip or knee.

Design
Network meta-analysis. Direct comparisons within trials were combined with indirect evidence from other trials by using a Bayesian model that allowed the synthesis of multiple time points.

Main outcome measure
Pain intensity. Secondary outcome was change in minimal width of joint space. The minimal clinically important difference between preparations and placebo was prespecified at -0.9 cm on a 10 cm visual analogue scale.

Data sources
Electronic databases and conference proceedings from inception to June 2009, expert contact, relevant websites.

Eligibility criteria for selecting studies
Large scale randomised controlled trials in more than 200 patients with osteoarthritis of the knee or hip that compared glucosamine, chondroitin, or their combination with placebo or head to head.

Results
10 trials in 3803 patients were included. On a 10 cm visual analogue scale the overall difference in pain intensity compared with placebo was -0.4 cm (95% credible interval -0.7 to -0.1 cm) for glucosamine, -0.3 cm (-0.7 to 0.0 cm) for chondroitin, and -0.5 cm (-0.9 to 0.0 cm) for the combination. For none of the estimates did the 95% credible intervals cross the boundary of the minimal clinically important difference. Industry independent trials showed smaller effects than commercially funded trials (P=0.02 for interaction). The differences in changes in minimal width of joint space were all minute, with 95% credible intervals overlapping zero.

Conclusions
Compared with placebo, glucosamine, chondroitin, and their combination do not reduce joint pain or have an impact on narrowing of joint space. Health authorities and health insurers should not cover the costs of these preparations, and new prescriptions to patients who have not received treatment should be discouraged.

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BMJ 2010; 341:c4675

JAMA打破葡萄糖胺有效治療退化性關節炎的「神話」

2010-09-23T16:11:00.000-07:00

Effect of glucosamine on pain-related disability in patients with chronic low back pain and degenerative lumbar osteoarthritis: a randomized controlled trial.

CONTEXT: Chronic low back pain (LBP) with degenerative lumbar osteoarthritis (OA) is widespread in the adult population. Although glucosamine is increasingly used by patients with chronic LBP, little is known about its effect in this setting. OBJECTIVE: To investigate the effect of glucosamine in patients with chronic LBP and degenerative lumbar OA. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, placebo-controlled trial conducted at Oslo University Hospital Outpatient Clinic, Oslo, Norway, with 250 patients older than 25 years of age with chronic LBP (>6 months) and degenerative lumbar OA.

INTERVENTIONS: Daily intake of 1500 mg of oral glucosamine (n = 125) or placebo (n = 125) for 6 months, with assessment of effect after the 6-month intervention period and at 1 year (6 months postintervention).

MAIN OUTCOME MEASURES: The primary outcome was pain-related disability measured with the Roland Morris Disability Questionnaire (RMDQ). Secondary outcomes were numerical scores from pain-rating scales of patients at rest and during activity, and the quality-of-life EuroQol-5 Dimensions (EQ-5D) instrument. Data collection occurred during the intervention period at baseline, 6 weeks, 3 and 6 months, and again 6 months following the intervention at 1 year. Group differences were analyzed using linear mixed models analysis.

RESULTS: At baseline, mean RMDQ scores were 9.2 (95% confidence interval [CI], 8.4-10.0) for glucosamine and 9.7 (95% CI, 8.9-10.5) for the placebo group (P = .37). At 6 months, the mean RMDQ score was the same for the glucosamine and placebo groups (5.0; 95% CI, 4.2-5.8). At 1 year, the mean RMDQ scores were 4.8 (95% CI, 3.9-5.6) for glucosamine and 5.5 (95% CI, 4.7-6.4) for the placebo group. No statistically significant difference in change between groups was found when assessed after the 6-month intervention period and at 1 year: RMDQ (P = .72), LBP at rest (P = .91), LBP during activity (P = .97), and quality-of-life EQ-5D (P = .20). Mild adverse events were reported in 40 patients in the glucosamine group and 46 in the placebo group (P = .48).

CONCLUSIONS: Among patients with chronic LBP and degenerative lumbar OA, 6-month treatment with oral glucosamine compared with placebo did not result in reduced pain-related disability after the 6-month intervention and after 1-year follow-up.

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JAMA. 2010; 304(1):45-52 (ISSN: 1538-3598)
TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00404079.

低溫治療 - Therapeutic Hypothermia

2010-09-22T20:22:00.000-07:00

Targeted Temperature Management for Comatose Survivors of Cardiac Arrest

Targeted temperature management, also known as therapeutic hypothermia, is a therapeutic intervention that is intended to limit neurologic injury after a patient's resuscitation from cardiac arrest. Hypothermia causes a reduction in brain metabolism, including a reduction in oxygen utilization and ATP consumption.

What are the indications for therapeutic hypothermia?
Therapeutic hypothermia should be considered for adult patients successfully resuscitated from a witnessed out-of-hospital cardiac arrest of presumed cardiac cause, though patients after in-hospital cardiac arrest may also benefit. This measure should also be considered in patients who are comatose, and in patients with an initial rhythm of ventricular fibrillation or nonperfusing ventricular tachycardia (or other initial rhythms such as asystole or pulseless electrical activity).

How is therapeutic hypothermia achieved?
Several different cooling methods are available for use in therapeutic hypothermia. In the pivotal clinical trials, cooling was achieved by the application of numerous ice packs around the head, neck, torso, and limbs or with the use of a cold-air mattress covering the entire body. Other methods of surface cooling include the use of water-circulating cooling blankets or pads, refrigerated cooling pads, and thermal beds. Core cooling can be achieved with the use of intravascular cooling catheters (made of metal or containing balloons filled with cold saline) or by means of intravenous infusion of cold fluids. The objective is to reach a target temperature of 32 to 34°C and to maintain that temperature for 24 hours, if feasible.

What additional patient management is necessary before hypothermia is induced?
A. Before hypothermia is induced, sedation, analgesia, and paralysis should be initiated to prevent shivering (which can lead to increased oxygen consumption, excessively laborious breathing, increased heart rate, and a general stress-like response, in addition to impeding the cooling process) and to minimize the patient’s discomfort.

What metabolic disturbances are induced by therapeutic hypothermia?
A. Hypothermia can induce metabolic disturbances, including hypokalemia, hypomagnesemia, hypophosphatemia, and hyperglycemia. Therefore, regular measurement of electrolyte and glucose levels is necessary to guide the appropriate amount of electrolyte substitution and insulin therapy. Leukopenia and thrombocytopenia may occur but typically do not require intervention.

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TEACHING TOPICS from the NEJM

氧氣沒有想像中有幫助

2010-09-14T18:42:00.000-07:00

Palliative Oxygen Offers No More Relief Than Intranasal Room Air
Simpler interventions might be preferable.

Intranasal oxygen is often used to relieve severe dyspnea in terminally ill patients, even when their PaO2 is not low enough to qualify for long-term oxygen therapy (i.e., below 55 mm Hg). But no clear evidence indicates that palliative oxygen has symptomatic benefits.

Investigators randomized 239 patients with life-limiting illness, refractory dyspnea, and PaO2 above 55 mm Hg to receive either oxygen or room air at 2L/minute via nasal cannula for at least 15 hours daily for 7 days. Beginning 2 days before the intervention started, patients were asked every morning and evening to rate their current dyspnea using a validated 10-point scale and to report secondary outcomes (e.g., quality of life).

No significant between-group differences were noted in reports of current dyspnea at any time. Both groups reported significant improvement during the course of the study (about 18% improvement in morning dyspnea and 9% improvement in evening dyspnea); the greatest decrease in both morning and evening dyspnea occurred within the first day of the intervention. Quality of life improved by about 12% in both groups.

Comment:
Evidence shows that air movement across the face (e.g., from a hand-held fan) helps relieve dyspnea, and intranasal gas (whether oxygen or room air) might have a similar effect. Oxygen use is costly, logistically demanding, and risky in some patients (e.g., smokers, those with hypercapnia). Except for patients with true hypoxia, simpler interventions may be preferable for relieving dyspnea at the end of life.

—
Bruce Soloway, MD
Published in Journal Watch General Medicine September 14, 2010

Citation(s): Abernethy AP et al. Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: A double-blind, randomised controlled trial. Lancet 2010 Sep 4; 376:784. (http://dx.doi.org/10.1016/S0140-6736(10)61115-4)

補充鈣補過頭小心會心肌梗塞！

2010-08-31T17:49:00.000-07:00

Calcium Supplementation Is Associated with Excess Risk for Myocardial Infarction
Marginal-to-moderate bone benefits must be weighed against cardiovascular risks.

Evidence suggests that calcium supplements hasten vascular calcification and increase mortality in patients with kidney failure and raise risk for myocardial infarction (MI) in healthy older women. To further investigate the association between supplemental calcium and adverse cardiovascular events, researchers conducted a meta-analysis of 15 double-blind, randomized trials in which participants (mean age at baseline, >40) received calcium supplements (>/= 500 mg daily) or placebo.

Patient-level data were available for five trials involving >8000 participants (77% women; median follow-up, 3.6 years). MIs occurred in 143 participants randomized to calcium supplements and 111 randomized to placebo — a significant difference. Calcium supplementation was not associated with excess risk for stroke or death. Analyses of trial-level data, involving 11 studies with nearly 12,000 patients, yielded findings similar to those that were based on patient-level data.

Comment:
Calcium supplementation is associated with excess risk for MI. Clinicians should weigh this risk against the marginal-to-modest benefits of calcium supplementation on bone density and fracture risk. Based on current data, the authors estimate that treating 1000 people with calcium supplements for 5 years would prevent only 26 fractures but would cause an additional 14 MIs.

—
Paul S. Mueller, MD, MPH, FACP
Published in Journal Watch General Medicine August 31, 2010

Citation(s):
Bolland MJ et al. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: Meta-analysis. BMJ 2010 Jul 29; 341:c3691. (http://dx.doi.org/10.1136/bmj.c3691)

Alteplase for stroke - up to 4.5 hr

2010-08-27T18:18:00.000-07:00

Alteplase Is Effective Up to 4.5 Hours After Onset of Ischemic Stroke
But earlier is better.

On the basis of reports published in September 2008 from two large international studies, professional stroke organizations extended the recommended time between symptom onset and administration of alteplase from 3 to 4.5 hours (JW Emerg Med Sep 24 2008 and JW Emerg Med Sep 15 2008). To assess implementation of the wider treatment window and its effects, investigators analyzed data for nearly 24,000 patients who were included in one of the study's stroke registry from 2002 to 2010.

Overall, 2376 patients received alteplase between 3 and 4.5 hours after symptom onset; the proportion of patients who were treated within this window was three times higher in the last quarter of 2009 than in the first quarter of 2008. Rates of poor outcomes were low: 7.1% of patients treated within 3 hours and 7.4% of those treated at 3 to 4.5 hours had symptomatic intracerebral hemorrhage and 12.3% and 12.0%, respectively, died within 3 months. However, in analyses adjusted for confounding variables, patients treated at 3 to 4.5 hours had significantly higher rates of symptomatic intracerebral hemorrhage (1 extra hemorrhage for every 200 patients) and 3-month mortality (1 extra death for every 333 patients), as well as significantly worse functional outcomes (odds ratio for functional independence, 0.84). Median time from admission to treatment was 65 minutes before and after the reports. The authors conclude that the extended treatment window was implemented rapidly with no overall increase in admission-to-treatment time and that although risk from alteplase was greater when administered at 3 to 4.5 hours, treatment was still beneficial.

Comment:
Although the U.S. FDA has not yet approved use of alteplase beyond 3 and up to 4.5 hours after onset of ischemic stroke symptoms, this evidence supports a wider treatment window and professional organizations recommend it. Nevertheless, time is brain, and eligible patients should be treated as soon as possible.

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine August 27, 2010

Citation(s): Ahmed N et al. Implementation and outcome of thrombolysis with alteplase 3–4.5 h after an acute stroke: An updated analysis from SITS-ISTR. Lancet Neurol 2010 Sep; 9:866.

超級細菌 (superbug)

2010-08-16T18:09:00.000-07:00

帶有NDM-1抗藥性基因的超級細菌(superbug)

NDM-1是一種抗藥性基因，該基因所產生的酵素在2009年底印度新德里發現，全名叫做New Delhi metallo-beta-lactamase 1 。若細菌帶有此基因，其分泌的酵素會分解beta-lactam類的抗生素。NDM-1主要存在於各種革蘭氏陰性細菌，尤其是腸內菌屬的細菌(Enterobacteriaceae)，例如Escherichia coli 與Klebsiella pneumoniae等等。細菌一但含有這種抗藥性基因，所有的beta-lactam類抗生素都對它沒有效，所以這些細菌常常被形容為超級細菌(superbug)。可能有效的藥物只剩下tigecycline與colistin。

由於國際活動交流及觀光旅遊日益興盛，所以抗藥性細菌的散播也很快。去年底在印度發現NDM-1的細菌以後，很快今年在英國，在一位曾經在印度接受洗腎治療的印度裔英國人身上，也發現了帶有同樣抗藥性基因的細菌。此外，美國、香港與比利時等地也都傳出病例。正因此，各國專家們擔心這個細菌很快就會散播到全世界，造成全球的健康問題，最近這個消息也占據了不少媒體的版面。

抗生素的發現讓人類的醫學向前跨越一大步，然而抗生素之大量使用與不當使用是造成細菌抗藥性增加的原因之一，而抗藥性基因在不同菌間交換與抗藥菌在不同宿主間之傳播也是細菌抗藥性增加的原因。

如何防止抗藥性細菌的傳播？抗藥性細菌會經由污染的手、衣物、醫療器材或環境來散播，因此您必須遵守洗手五時機：接觸病人前後、執行清潔/無菌操作技術前、暴觸病人體液風險後以及接觸病人週遭環境後。

若您有興趣想要閱讀NDM-1的相關期刊文章，請參閱:

1. Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study. Lancet Infect Dis. 2010 Aug 10.

2. Characterization of a new metallo-beta-lactamase gene, bla(NDM-1), and a novel erythromycin esterase gene carried on a unique genetic structure in Klebsiella pneumoniae sequence type 14 from India. Antimicrob Agents Chemother. 2009 Dec;53(12):5046-54.

麻指頭只須一針！

2010-08-14T00:30:00.000-07:00

Digital Nerve Block: One Injection Is as Good as Two
Preliminary data support use of a single-injection method for fingertip injuries and infections.

The traditional method of digital nerve block involves two subcutaneous injections with the dorsal approach to block the four digital nerves at the base of the finger. An alternative approach involves a single subcutaneous injection of 2 to 3 mL of local anesthetic on the palmar surface at the base of the digit just distal to the proximal skin crease, followed by massage of the anesthetic into the area. Researchers conducted a multicenter, randomized controlled trial to compare these two methods in 76 patients older than 16 years who presented to three emergency departments in the U.K. with fingertip injuries or infections that required local anesthesia.

The proportion of patients who were adequately anesthetized did not differ significantly between the one-injection and two-injection groups at 5 minutes (76% and 65%) or at 10 minutes (89% and 82%). Clinician satisfaction scores were significantly higher for the one-injection technique (mean, 8.1 vs. 6.8 on a 10-point scale).

Comment: The authors could not recruit the intended 500 patients to adequately power the study, in part because many clinicians preferred the subcutaneous method and adopted it as their normal practice. This simple single-injection approach works beautifully to anesthetize the distal finger; however, because this method does not block the dorsal branches of the digital nerve, it might be less effective for injuries proximal to the distal-interphalangeal joint.

—

Diane M. Birnbaumer, MD, FACEP
Published in Journal Watch Emergency Medicine August 13, 2010

Citation(s): Cannon B et al. Digital anaesthesia: One injection or two? Emerg Med J 2010 Jul; 27:533.

Sellick maneauver 的缺點

2010-07-23T18:45:00.000-07:00

Cricoid Pressure During Intubation of Trauma Patients: Helpful or Harmful?
Release of cricoid pressure improved the laryngoscopic view in 11 of 22 patients.

The purported value of cricoid pressure during intubation is to protect the pulmonary tree from aspiration of vomitus. However, recent evidence suggests that cricoid pressure impairs laryngoscopic view, reduces bag-valve-mask ventilation efficiency, and does not prevent aspiration (Ann Emerg Med 2007; 50:653). In a prospective observational study, researchers compared the effect on laryngoscopic view of three laryngeal maneuvers (release of cricoid pressure, BURP [backwards, upwards, rightward pressure], and laryngeal manipulation under direct vision) in 400 adult trauma patients who were intubated with cricoid pressure in a London air–ground emergency medical services system during a 16-month period. Airways were managed by attending or senior residents in emergency medicine, critical care, or anesthesia. Removal of the laryngoscope, additional preoxygenation, and repeat laryngoscopy was defined as an additional attempt.

Overall, 87.5% of patients were intubated on the first attempt, and 98.8% were intubated within two attempts. Four patients required three attempts, and one patient required rescue cricothyroidotomy. The laryngoscopic view was improved by at least one Cormack-Lehane grade with release of cricoid pressure in 11 of 22 patients (50%), with laryngeal manipulation in 15 of 25 patients (60%), and with the BURP maneuver in 9 of 14 patients (64%). No maneuver made the view worse. Release of cricoid pressure was followed by vomiting in two patients (9%), both of whom had prolonged bag-valve-mask ventilation; neither patient developed aspiration pneumonia.

Comment:
Cricoid pressure during intubation is considered necessary by many emergency medicine societies. These findings place this recommendation under scrutiny, just as the widely promulgated need for in-line cervical stabilization has recently been challenged (JW Emerg Med Aug 14 2009). Until a randomized, prospective trial demonstrates benefit from cricoid pressure, practitioners performing emergency trauma (and nontrauma) intubations should consider cricoid pressure an optional maneuver and be aware that it might lower the chance for successful intubation.

—
John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine July 23, 2010

CITATION(S): Harris T et al. Cricoid pressure and laryngeal manipulation in 402 pre-hospital emergency anaesthetics: Essential safety measure or a hindrance to rapid safe intubation? Resuscitation 2010 Jul; 81:810.

收縮壓維持在130左右最好

2010-07-20T17:15:00.000-07:00

Blood Pressure Control in Patients with Diabetes and Coronary Artery Disease
No benefit for lowering BP to below 130/80 mm Hg

Several organizations recommend a blood pressure (BP) goal of below 130/80 mm Hg for patients with diabetes. To determine whether this goal is appropriate for patients with diabetes and known coronary artery disease (CAD), researchers conducted a secondary analysis of data from the INVEST study, a randomized trial in which hypertensive patients with CAD received β-blocker–based or calcium-channel blocker–based regimens (JW Gen Med Dec 23 2003). Researchers reported previously that overly aggressive BP lowering in these patients was associated with excess risk for adverse cardiovascular events (JW Gen Med Aug 10 2006); now, they focus on subset of 6400 INVEST patients with diabetes.

Patients were divided into three groups according to their average systolic BP during the trial: tight control (below 130 mm Hg), usual control (130–139 mm Hg), or uncontrolled (above 139 mm Hg). During median follow-up of 3 years, the primary outcome (all-cause mortality or nonfatal myocardial infarction or stroke) occurred in 12.7% of the tight-control group, in 12.6% of the usual-control group, and in 19.8% of the uncontrolled group. In adjusted analyses that included secondary outcomes, researchers found no difference between tight and usual control. After an additional 5-year follow-up, all-cause mortality was higher in the tight-control group than in the usual-control group (22.8% vs. 21.8%; P=0.04).

Comment: Because this was a post hoc analysis of observational data from patients who weren't randomized to different BP targets, confounding factors could have influenced the findings. However, in the recently published ACCORD BP trial, high-risk patients with diabetes were randomized to one of two systolic BP targets (120 mm Hg or 140 mm Hg), and researchers found no difference in adverse cardiovascular events between the groups (JW Cardiol Mar 14 2010). Taken together, INVEST and ACCORD suggest that a systolic BP goal in the 130s is reasonable for hypertensive diabetic patients with CAD or multiple cardiovascular risk factors.

—
Thomas L. Schwenk, MD
Published in Journal Watch General Medicine July 20, 2010

Citation(s): Cooper-DeHoff RM et al. Tight blood pressure control and cardiovascular outcomes among hypertensive patients with diabetes and coronary artery disease. JAMA 2010 Jul 7; 304:61. (http://dx.doi.org/10.1001/jama.2010.884)

Pelvic packing for pelvic fractures

2010-07-20T17:10:00.000-07:00

Direct retroperitoneal pelvic packing versus pelvic angiography: A comparison of two management protocols for haemodynamically unstable pelvic fractures.

OBJECTIVE: To evaluate the outcomes of haemodynamically unstable cases of pelvic ring injury treated with a protocol focused on either direct retroperitoneal pelvic packing or early pelvic angiography and embolisation.

METHODS: A retrospective review of a prospectively collected database in an academic level I trauma centre, treating matched haemodynamically unstable cases of pelvic fracture with either pelvic packing (PACK group, n=20) or early pelvic angiography (ANGIO group, n=20). Physiological markers of haemorrhage, time to intervention, transfusion requirements, complications and early mortality were recorded.

RESULTS: The PACK group underwent operative packing at a median of 45min from admission; the median time to angiography in the ANGIO group was 130min. The PACK group, but not the ANGIO group, demonstrated a significant decrease in blood transfusions over the next 24h post intervention. In the ANGIO group, ten people required embolisation and six died, two from acute haemorrhage; in the PACK group, three people required embolisation; four died, none due to uncontrolled haemorrhage.

CONCLUSIONS: Pelvic packing is as effective as pelvic angiography for stabilising haemodynamically unstable casualties with pelvic fractures, decreases need for pelvic embolisation and post-procedure blood transfusions, and may reduce early mortality due to exsanguination from pelvic haemorrhage.

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Injury. 2009 Jan;40(1):54-60. Epub 2008 Nov 30.

單次掉血壓也可能是嚴重創傷的指標之一

2010-07-16T20:04:00.000-07:00

Beware of Even a Single Hypotensive Blood Pressure Measurement in Trauma Patients
A single systolic BP reading less than 105 mm Hg in the emergency department portends serious injury and the potential need for immediate surgical or endovascular intervention.

Hypotension in trauma patients typically occurs after loss of 30% of total blood and, if persistent, can lead to end-organ injury resulting from hypoperfusion and uncompensated shock. In a prospective observational study at a single level I trauma center, researchers determined the systolic blood pressure (SBP) cutpoint value that best predicts the need for therapeutic surgical or endovascular procedures; 145 adult patients (77% men; 54% with blunt mechanism of injury) who had at least one SBP measurement below 110 mm Hg during initial trauma care were enrolled during a 6-month period. Exclusion criteria were transfer from another hospital, injury more than 2 hours before emergency department (ED) arrival, and isolated prehospital hypotension (below 90 mm Hg) or more than two SBP readings below 90 mm Hg in the ED.

SBP was measured manually within 10 minutes of ED arrival and then automatically at least every 5 minutes for the first 15 minutes, followed by every 15 minutes for the first hour, and then hourly thereafter. Cutpoint analysis showed that a single SBP measurement below 105 mm Hg best predicted need for immediate intervention. Patients with a single SBP measurement below 105 mm Hg, compared to those with no measurement below 105 mm Hg, were significantly more likely to undergo therapeutic intervention (38% vs. 10%), to be admitted to a surgical intensive care unit (54% vs. 25%), and to have a prolonged hospital stay (mean, 8.3 vs. 4.2 days). Other independent predictors of need for therapeutic intervention were gunshot wound mechanism of injury, higher injury severity score, and longer duration of initial resuscitation.

Comment:

This small study suggests that even a single SBP measurement below 105 mm Hg in patients with trauma should not be dismissed as erroneous. A single low reading could reflect impending shock and indicate need for aggressive management as well as therapeutic surgical or endovascular procedures.

—

John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine July 16, 2010

Citation(s): Seamon MJ et al. Just one drop: The significance of a single hypotensive blood pressure reading during trauma resuscitations. J Trauma 2010 Jun; 68:1289.

Af or AF可在急診做cardioversion

2010-07-02T22:51:00.000-07:00

Rapid Treatment and Discharge of Patients with Recent-Onset Atrial Fibrillation or Flutter
Rapid cardioversion and discharge home is safe for emergency department patients who present within 48 hours of onset of atrial fibrillation or flutter.

Researchers evaluated the efficacy and safety of a protocol for rapid emergency department (ED) cardioversion and discharge of patients with recent-onset (<48 hours) atrial fibrillation or atrial flutter in a retrospective observational study of 660 consecutive patients (95% with atrial fibrillation, 5% with atrial flutter) at a single ED in Canada from 2000 to 2005. The protocol involved ED pharmacologic cardioversion with intravenous (IV) procainamide (1 g during 60 minutes) and, if needed, electrical cardioversion, followed by discharge home within 1 hour after cardioversion.

Sixty percent of patients with atrial fibrillation and 28% of those with atrial flutter converted to sinus rhythm with IV procainamide. Electrical cardioversion (not attempted in 32 patients) was successful in 92% and 100% of the remaining 243 patients with fibrillation and 20 with flutter, respectively. Overall, 97% of patients were discharged home, and 93% of discharged patients were in sinus rhythm. Median ED stay was 4.9 hours. Adverse events (including transient hypotension and bradycardia) occurred in 7.6% of patients, and 8.6% of patients relapsed within 7 days; no cases of torsades de pointes or stroke were reported and no deaths occurred.

Comment:
Primary ED cardioversion (by IV or oral antidysrhythmic agent [JW Gen Med Jan 11 2005 ] or synchronized electrical cardioversion) is a reasonable option for patients with uncomplicated atrial fibrillation or atrial flutter.

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine July 2, 2010

Citation(s): Stiell IG et al. Association of the Ottawa Aggressive Protocol with rapid discharge of emergency department patients with recent-onset atrial fibrillation or flutter. CJEM 2010 May; 12:181.

兒童誤吞鈕型電池：比想像中嚴重

2010-06-25T23:56:00.000-07:00

Alarming Rise in Major Complications from Button Battery Ingestions
Ingestion of large button batteries, particularly lithium cells, accounts for the increase in poor outcomes.

To describe recent trends in button battery ingestions, investigators collected data from the National Poison Data System (NPDS; 56,535 cases reported during 1985–2009), the National Battery Ingestion Hotline (NBIH; 8161 cases during 1990–2008), and all 73 major (life-threatening or disabling) and 13 fatal cases ever reported in the medical literature or to the NBIH.

NPDS data showed no consistent trend in annual frequency of button battery ingestions. However, the proportion of major or fatal cases increased 6.7-fold between the first 3 years (1985–1987) and last 3 years (2007–2009). Children younger than 6 years accounted for 68% of NPDS cases and 62% of NBIH cases; all NBIH fatalities and 85% of major cases were in patients younger than 4 years. In logistic regression analysis of NBIH data, predictors of poor outcome were large battery diameter (20–25 mm; odds ratio, 24.6), age less than 4 years (OR, 3.2), and ingestion of more than one battery (OR, 2.1). During 2000–2009, 92% of major and fatal cases were from ingestion of 20-mm lithium cells. Injuries (e.g., severe burns, esophageal stenosis, bilateral vocal cord paralysis) occurred as soon as 2 hours after ingestion. Most major and fatal cases occurred in children less than 4 years old (92%) and were unwitnessed (56%), and many unwitnessed cases were initially misdiagnosed (46%). The authors present a management algorithm that recommends endoscopic removal of esophageal button batteries within 2 hours of ingestion.

Comment:

These data are sobering. Physicians should keep button cells high on the list of differential diagnoses for any child who presents with airway obstruction or wheezing, drooling, vomiting, chest discomfort, difficulty swallowing or refusal to eat, or choking or coughing while eating or drinking. Once an esophageal button battery is identified, consultants must be mobilized for emergent removal.

—

Katherine Bakes, MD
Published in Journal Watch Emergency Medicine June 25, 2010

Citation(s): Litovitz T et al. Emerging battery-ingestion hazard: Clinical implications. Pediatrics 2010 Jun; 125:1168.

COPD使用類固醇

2010-06-24T22:27:00.000-07:00

Steroid Dosage and Route in Patients Admitted for COPD
Oral low-dose use was associated with less treatment failure than was high-dose parenteral use.

Patients admitted for chronic obstructive pulmonary disease (COPD) usually receive systemic steroids, which have been associated with better outcomes in several prior randomized trials, but the best dose is still in question. Several major clinical practice guidelines recommend low-dose oral steroids.

In a retrospective cohort study, based on data from 414 U.S. hospitals, Massachusetts investigators compared outcomes in nearly 80,000 patients admitted for COPD to non–intensive care unit settings. About 74,000 received parenteral steroids (equivalent to a median dose of 600 mg of prednisone total for the first 2 days), and the rest received oral prednisone (median, 60 mg for the first 2 days). Treatment failure — defined as need for mechanical ventilation after the first 2 days, death, or readmission for COPD within 30 days — occurred in 11% of all patients.

In analyses adjusted for about 50 clinical and demographic variables, as well as propensity scores, treatment failure was 16% lower in patients who received oral low-dose steroids than in those who received parenteral steroids; length of stay and cost were about 10% lower in the low-dose group.

Comment: Although this study was retrospective, its sophisticated analyses convinced editorialists that the results should influence clinical practice and that a randomized controlled trial would be prohibitive in size and cost and is unnecessary. A worrisome secondary finding is that the vast majority of COPD patients received high-dose parenteral steroids, despite the contrary recommendations of major national and international guidelines — including those of the Global Initiative for Chronic Obstructive Lung Disease (GOLD).

—

Thomas L. Schwenk, MD
Published in Journal Watch General Medicine June 24, 2010

Citation(s): Lindenauer PK et al. Association of corticosteroid dose and route of administration with risk of treatment failure in acute exacerbation of chronic obstructive pulmonary disease. JAMA 2010 Jun 16; 303:2359. (http://dx.doi.org/10.1001/jama.2010.796)

Vertigo 如何診治？

2010-06-22T18:04:00.000-07:00

Managing patients with vertigo can be very challenging. This practical summary of the causes and management of "dizziness" is useful. Three types are described:

Episodic becoming chronic-migraine, Meniere's disease (hearing loss, tinnitus, vertigo), benign paroxysmal positional vertigo (BPPV, rotational vertigo lasting a few seconds related to head movements)
Single attack but with residual symptoms-vestibular neuritis (a single, disabling attack that lasts a few days)
Chronic, slowly progressive-polyneuropathies, idiopathic bilateral vestibular failure

Management includes:

Treatment of the specific vestibular condition
Symptomatic treatment of vertigo and nausea
Physical rehabilitation

Source: Practical Neurology 2010;10:129-139
http://pn.bmj.com/content/10/3/129.full.pdf

氧氣治療AMI...有害？！

2010-06-18T05:41:00.000-07:00

Routine use of oxygen in people who have had a heart attack
Most guidelines for the treatment of people who are having a heart attack recommend that the patient should be given oxygen to breathe. We looked for the evidence to support this practice by searching for randomised controlled trials that compared the outcomes in patients given oxygen to the outcomes for patients given normal air to breathe. We were primarily interested in seeing whether there was a difference in the number of people who died but we also looked at whether administering oxygen reduced pain.

We found three randomised controlled trials that compared one group given oxygen to another group given air. These trials involved a total of 387 patients of whom 14 died. Of those who died, nearly three times as many people known to have been given oxygen died compared to those known to have been given air. However, because the trials had few participants and few deaths this result does not necessarily mean that giving oxygen increases the risk of death. The difference in numbers may have occurred simply by chance. Nonetheless, since the evidence suggests that oxygen may in fact be harmful, we think it is important to evaluate this widely used treatment in a large trial, as soon as possible, to make sure that current practice is not causing harm to people who have had a heart attack.

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http://www2.cochrane.org/reviews/en/ab007160.html

Syphilis and azithromycin

2010-06-17T22:14:00.000-07:00

Treating Syphilis Without Penicillin
A large study finds that a single oral dose of azithromycin can be curative in patients with early syphilis.

Even after all these years, a single dose of intramuscular penicillin G remains the preferred treatment for early-stage syphilis. The usual alternative, oral doxycycline, is problematic because several weeks of treatment are needed, and poor patient adherence can compromise efficacy.

In a multinational randomized nonblinded trial, 517 nonpregnant, HIV-negative adults with primary, secondary, or early latent syphilis received benzathine penicillin G (2.4 million units administered in 2 intramuscular injections) or azithromycin (2 g, administered as four 500-mg tablets). After 6 months, about 75% of patients in each group were judged as cured by the usual serologic standard of a drop in rapid plasma reagin (RPR) titer of 2 dilutions. Four patients had clear treatment failure with a significant rise in RPR titers; all had received azithromycin. Adverse effects, primarily gastrointestinal, were more common in the azithromycin group.

Comment:

Single-dose azithromycin is an attractive treatment option for syphilis: It can be given under observation, is generally well tolerated, and can also be effective against chancroid, chlamydia, and gonorrhea. This study adds to the evidence that it works for syphilis, but concerns remain. Among them: efficacy in HIV infection, efficacy in pregnancy, and the observation that a mutation encoding for macrolide resistance is rapidly emerging in Treponema pallidum isolates.

—

Abigail Zuger, MD
Published in Journal Watch General Medicine June 17, 2010

Citation(s): Hook EW III et al. A phase III equivalence trial of azithromycin versus benzathine penicillin for treatment of early syphilis. J Infect Dis 2010 Jun 1; 201:1729.

Statin 的副作用？

2010-06-15T20:59:00.000-07:00

Unintended Effects of Statin Drugs
Kidney failure and cataracts were associated significantly with statin use.

Statins lower risk for adverse cardiovascular events, especially in high-risk patients. In this large prospective U.K. cohort study, investigators sought to quantify unintended effects of these widely used drugs.

Of the more than 2 million study participants (age range, 30–84), about 225,000 were new statin users: 160,000 were prescribed simvastatin, 50,000 received atorvastatin, and 15,000 received pravastatin, rosuvastatin, or fluvastatin. Statin use was associated significantly with lower risk for esophageal cancer and higher risks for liver dysfunction (alanine transaminase levels 3x upper limit of normal), myopathy (clinical diagnosis or creatinine kinase level 4x upper limit of normal), acute kidney failure, and cataracts; liver dysfunction and acute kidney failure were dose-dependent. Adverse effects for individual statins were similar, except for liver dysfunction, in which risk was highest for fluvastatin. All excess risks persisted during treatment and returned to normal after drug cessation. Statin use was not associated with risk for osteoporotic fracture, venous thromboembolism, dementia, Parkinson disease, rheumatoid arthritis, or cancers (stomach, lung, breast, colon, kidney, and prostate cancers or melanoma).

Comment:

Most clinicians are familiar with statin-associated liver dysfunction and myopathy. The results of this study suggest that clinicians should be familiar with and monitor for two more possible statin-associated adverse effects: acute kidney failure and cataracts. In addition, with the exception of esophageal cancer risk, the results are consistent with those of a prior meta-analysis, in which researchers found no association between statin use and cancer risk (JW Cardiol Mar 9 2006).

—

Paul S. Mueller, MD, MPH, FACP
Published in Journal Watch General Medicine June 15, 2010

Citation(s):
Hippisley-Cox J and Coupland C. Unintended effects of statins in men and women in England and Wales: Population based cohort study using the QResearch database. BMJ 2010 May 20; 340:c2197. (http://dx.doi.org/10.1136/bmj.c2197)

又一篇Plavix加PPI

2010-06-08T22:05:00.000-07:00

Using Clopidogrel with a Proton-Pump Inhibitor
Risks for rehospitalization for myocardial infarction or stent placement were higher with combined therapy.

Studies have suggested that clopidogrel's efficacy is weakened if it is used in combination with a proton-pump inhibitor (PPI), given that the drugs compete for CYP2C19 activity. However, earlier retrospective studies might not have fully accounted for the likelihood that patients who receive PPIs are at higher baseline risk for cardiovascular events than are those who do not.

In this retrospective cohort study, based on U.S. claims data, researchers assessed risks for rehospitalization for myocardial infarction (MI) or stent placement among 2066 patients (mean age, 69) who were discharged from hospitals after MI or coronary stent placement; half the patients received clopidogrel alone, and half received it in combination with a PPI. Propensity scores were used to match patients by baseline cardiovascular risk. During 1 year of follow-up, combined-therapy recipients were more likely than clopidogrel-alone recipients to be rehospitalized for MI or coronary stent procedures (27.6 vs. 14.3 events per 100 person-years) or to be rehospitalized for MI (9.7 vs. 4.1 events per 100 person-years).

Comment:

Once again, PPIs have been shown to lower the efficacy of clopidogrel. Of note, a few studies have suggested that pantoprazole inhibits CYP2C19 less than other PPIs do and that it does not impair clopidogrel efficacy. In this study, pantoprazole had adverse effects that were similar to those of other PPIs. Discouraging use of PPIs in conjunction with clopidogrel seems prudent.

—

Jamaluddin Moloo, MD, MPH

Published in Journal Watch General Medicine June 8, 2010

Citation(s):
Stockl KM et al. Risk of rehospitalization for patients using clopidogrel with a proton pump inhibitor. Arch Intern Med 2010 Apr 26; 170:704. (http://dx.doi.org/10.1001/archinternmed.2010.34)

TPA for stroke之4.5小時黃金時間

2010-05-28T18:28:00.000-07:00

No Benefit from Intravenous Alteplase When Given After 4.5 Hours of Stroke Onset
Risk for favorable outcomes decreases with increasing time to treatment from stroke onset, and, after 4.5 hours, alteplase treatment might increase mortality.

What is the optimal interval between stroke onset and intravenous recombinant tissue plasminogen activator (rt-PA) administration?

Researchers conducted an updated analysis of pooled data from eight trials involving 3670 patients (median age, 68; age range, 19–101) who were randomized to receive rt-PA or placebo within 360 minutes of onset of stroke symptoms.

In multivariate logistic regression analysis, the odds of a favorable 3-month outcome (based on modified Rankin scale score, Barthel index score, and National Institutes of Health Stroke Scale score) were inversely related to time from onset of symptoms to rt-PA treatment, with no treatment benefit after about 270 minutes. Adjusted odds of favorable 3-month outcomes were 2.55 for 0–90 minutes, 1.64 for 91–180 minutes, 1.34 for 181–270 minutes, and 1.22 for 271–360 minutes. Adjusted odds of mortality increased with time to treatment, ranging from 0.78 for 0–90 minutes to 1.49 for 271–360 minutes. Large parenchymal bleeds occurred in 5.2% of rt-PA patients versus 1% of controls and were independent of time-to-treatment interval. The authors conclude that time from stroke onset to treatment should be minimized and that after 4.5 hours, "risk might outweigh benefit." An editorialist adds that, in large middle cerebral artery infarcts, "20 million additional neurons die every 10 min[utes] if reperfusion is not achieved."

Comment:

These data suggest that the risk for favorable outcomes decreases by a factor of about two for every 90-minute delay in treatment from stroke onset and that after 4.5 hours, rt-PA treatment might increase mortality. Lytic therapy for acute stroke must be given at the earliest possible time. Extension of the window for treatment to 4.5 hours is not a license for delay; every minute counts.

—

Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine May 28, 2010

Citation(s):
Lees KR et al. Time to treatment with intravenous alteplase and outcome in stroke: An updated pooled analysis of ECASS, ATLANTIS, NINDS, and EPITHET trials. Lancet 2010 May 15; 375:1695.
Saver JL and Levine SR. Alteplase for ischaemic stroke — Much sooner is much better. Lancet 2010 May 15; 375:1667.

Infectious Mononucleosis

2010-05-26T18:51:00.000-07:00

Infectious Mononucleosis

Seroepidemiologic surveys indicate that over 95% of adults worldwide are infected with EBV. In industrialized countries and higher socioeconomic groups, half the population has primary EBV infection between 1 and 5 years of age, with another large percentage becoming infected in the second decade. Because economic and sanitary conditions have improved over past decades, EBV infection in early childhood has become less common, and more children are susceptible as they reach adolescence.

What is the classic triad of presenting signs of infectious mononucleosis?
Pharyngitis (usually subacute in onset), fever, and lymphadenopathy constitute the classic triad of presenting signs of infectious mononucleosis. Sore throat and malaise or fatigue are the most common presenting symptoms. Palatal petechiae, periorbital edema, and rash are less common.

How should infectious mononucleosis be diagnosed?
In the presence of mononucleosis symptoms, a positive heterophile antibody test has a sensitivity of approximately 85% and a specificity of approximately 94% regarding a diagnosis of infectious mononucleosis. However, heterophile antibody tests are negative in 25% of patients during the first week of infection and in 5 to 10% during or after the second week. The detection of at least 10% atypical lymphocytes on a peripheral-blood smear in a patient with mononucleosis has a sensitivity of 75% and specificity of 92% for the diagnosis of infectious mononucleosis. It is reasonable to screen patients who have suspected infectious mononucleosis for group A streptococcal infection with the use of a throat swab and rapid antigen testing or culture.

How is infectious mononucleosis transmitted?
A: EBV transmission occurs predominantly through exposure to infected saliva, often as a result of kissing and less commonly, by means of sexual transmission. The incubation period, from the time of initial exposure to the onset of symptoms, is estimated at 30 to 50 days.

How should patients with infectious mononucleosis be managed?
A: On the basis of clinical experience, supportive care is recommended for patients with infectious mononucleosis. Acetaminophen or nonsteroidal antiinflammatory agents are recommended to manage fever, throat discomfort, and malaise. Adequate fluid intake and nutrition should also be encouraged. Although getting adequate rest is prudent, bed rest is unnecessary. Patients may excrete high levels of EBV in their saliva in the year after onset of infectious mononucleosis, but special precautions against transmission of EBV are not necessary, since most people are EBV seropositive. To minimize the risk of splenic rupture, patients may consider a return to contact sports after a minimum of 3 weeks after onset of symptoms or after they are afebrile, lack clinical symptoms or findings, and feel well enough to play — whichever comes first.

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New England Journal of Medicine - Vol. 362, No. 21

小朋友用ondanstron要注意什麼？

2010-05-21T18:18:00.000-07:00

Does Ondansetron Mask Alternative Diagnoses in Children with Suspected Gastroenteritis?
Children who received ondansetron were more likely to return and to be admitted at the return visit but were not more likely to be given alternative diagnoses.

Does use of ondansetron in children with suspected gastroenteritis affect likelihood of admission, return visits, or alternative diagnoses? To find out, investigators conducted a retrospective chart review of 34,117 patients (age range, 3 months to 18 years) who received diagnoses of vomiting or gastroenteritis at two tertiary care pediatric emergency departments (EDs) over a 3-year period. Fifty-eight percent of patients received ondansetron.

In logistic regression analyses, patients who received ondansetron were significantly less likely than those who did not receive ondansetron to be admitted on the initial visit (odds ratio, 0.47) but were significantly more likely to return within 72 hours (OR, 1.45) and to be admitted on the return visit (OR, 1.74). Overall, patients who received ondansetron were significantly less likely to be admitted during the initial or return visit (5.3% vs. 7.3%). Of 443 patients who returned and were admitted, 76 (17%) received alternative diagnoses, most often appendicitis (16 patients), intussusception (10), bacteremia (8), and pyelonephritis (7). The likelihood of an alternative diagnosis was not associated with ondansetron use but was significantly associated with documented abdominal pain on the initial visit.

Comment: This large study provides convincing evidence that ondansetron does not usually mask alternative diagnoses in children with suspected gastroenteritis. Therefore, physicians should feel comfortable using this effective antiemetic but continue to consider etiologies of vomiting other than gastroenteritis and provide clear instructions regarding when to return to the ED.

—
Katherine Bakes, MD
Published in Journal Watch Emergency Medicine May 21, 2010

Citation(s): Sturm JJ et al. Ondansetron use in the pediatric emergency department and effects on hospitalization and return rates: Are we masking alternative diagnoses? Ann Emerg Med 2010 May; 55:415.

血糖控制太快也可能出問題...

2010-05-21T03:40:00.000-07:00

Treatment-Induced Diabetic Neuropathy
An unusual complication of rapid intensive glycemic control

In sporadic case reports — some published more than 50 years ago — clinicians have described acute severe painful neuropathy that can occur during intensive treatment of patients with poorly controlled diabetes. Researchers now describe 16 patients with this condition who were referred to a Boston diabetic neuropathy clinic.

Each patient developed severe neuropathic pain within 8 weeks of initiating intensive glycemic control. Nine patients (age range, 19–29) had type 1 diabetes, and 7 patients (age range, 31–58) had type 2 diabetes. Other common causes of neuropathy were ruled out. Average glycosylated hemoglobin levels were about 14% before intensive glycemic control and about 7% afterward. Pain was in a stocking-glove distribution in 13 patients and was diffuse in 3 patients. Autonomic symptoms (e.g., orthostatic hypotension, gastrointestinal dysfunction) occurred commonly, and standardized tests of sympathetic and parasympathetic function were abnormal in most patients. Retinopathy also worsened during the first 6 months of sustained glycemic control. Pain subsided eventually in most patients, but only after 1 to 2 years of combination drug therapies for neuropathic pain.

Comment:

In this case series — the largest to date — researchers make a convincing case for the existence of what they call "treatment-induced diabetic neuropathy." I have seen several such patients, but until now I was unaware of this syndrome. The pathophysiology and incidence of this clinical entity are unclear. However, the parallel worsening of neuropathy and retinopathy suggests a common mechanism, and, interestingly, transient worsening of retinopathy during the first year of intensive insulin therapy has occurred previously in clinical trials.

—

Allan S. Brett, MD
Published in Journal Watch General Medicine May 20, 2010

Citation(s): Gibbons CH and Freeman R. Treatment-induced diabetic neuropathy: A reversible painful autonomic neuropathy. Ann Neurol 2010 Apr; 67:534.

AAA Repair

2010-05-19T18:05:00.000-07:00

Abdominal Aortic Aneurysm Repair

Randomized trials have shown that for patients with a large abdominal aortic aneurysm endovascular repair offers a perioperative survival benefit over open repair. However, this advantage is not sustained beyond 2 years after surgery. There is concern that endovascular repair lacks durability, which may lead to an increased risk of late rupture, and that more reinterventions are required in patients undergoing this technique.

How does survival differ among patients who were treated with endovascular and open repair of abdominal aortic aneurysm?
Six years after randomization, the cumulative overall survival rates were 69.9% for open repair and 68.9% for endovascular repair, for a difference of 1.0 percentage point (95% confidence interval, −8.8 to 10.8; P=0.97). The increased perioperative mortality after open repair was counterbalanced by a larger number of deaths after discharge following endovascular repair.

What were the most common complications after repair of abdominal aortic aneurysms?
A: For open repair, the most frequent secondary intervention was correction of an abdominal incisional hernia, whereas endovascular-repair interventions were most often performed because of endograft-related complications such as endoleak and endograft migration.

What were the most common causes of death among patients who had undergone an abdominal aortic aneurysm repair?
A: The most common causes of death were cardiovascular causes (myocardial infarction, cardiac arrest, congestive heart failure, stroke and ruptured aneurysm), cancer, and pulmonary causes.

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http://content.nejm.org/cgi/content/abstract/362/20/1881

Lactate clearance 和 ScvO2 一樣好

2010-04-29T05:45:00.000-07:00

Lactate Clearance vs Central Venous Oxygen Saturation as Goals of Early Sepsis Therapy: A Randomized Clinical Trial.

Early goal-directed fluid resuscitation is the cornerstone of therapy for septic shock, but the optimal target for goal-directed resuscitation has not been well studied. The investigators sought to determine whether lactate clearance and central venous oxygen saturation (ScvO2) are equally effective as guides for early sepsis resuscitation. A cohort of 300 patients presenting to the emergency department with septic shock were randomly assigned to resuscitation guided either by normalization of ScvO2 (above 70%) or lactate clearance (at least 10% from baseline or remaining below 2 mmol/L), in addition to standard goals for mean arterial and central venous pressure. The 2 groups did not differ in the treatments that were administered during the 6 hours of goal-directed resuscitation or during the first 72 hours of hospitalization. Death occurred in 23% of patients managed with the ScvO2 protocol and in 17% of patients managed with the lactate clearance protocol, with no difference in adverse events between the 2 groups. The investigators concluded that early goal-directed fluid resuscitation of patients with septic shock can be safely guided by either ScvO2 or lactate clearance.

Hint:
A high ScvO2 cannot always be considered normal because dysfunctional tissue oxygen extraction (as in sepsis) may lead to increased ScvO2and thus falsely reassure the clinician about the health of the patient

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JAMA. 2010;303:739-746

聲音嘶啞(hoarseness)的注意事項

2010-04-27T03:21:00.000-07:00

Hoarseness
A useful reminder about patients who complain of a hoarse voice:

Red flag symptoms are persistent hoarseness for more than three weeks, difficulty or pain on swallowing, haemoptysis, earache with normal otoscopy, weight loss, and heavy smoking or alcohol intake
Urgent ! chest x ray is needed if hoarseness persists for more than 3 weeks (especially if the patient is a heavy drinker, smoker, or over 50 years old)
If the x ray is positive, refer urgently for suspected lung cancer. If it's negative, refer urgently for suspected head and neck cancer
Routine ENT referral is advised for recurrent but non persistent (less than 3 weeks) hoarseness with no red flag symptoms
Advise patients to stop smoking, reduce alcohol intake, and improve vocal hygiene
Treat any exacerbating conditions such as oral thrush, asthma, or rhinitis

Source: BMJ 2010;340:c522

有5%的SAH是NE正常但已中線位移

2010-04-24T02:52:00.000-07:00

Midline Shift or Herniation in Patients with Subarachnoid Hemorrhage and Normal Neurological Exams

In a retrospective study, 5% of patients with spontaneous SAH and normal neurological exams had computed tomographic findings that contraindicated lumbar puncture.

Controversy surrounds the issue of whether computed tomography (CT) is required before lumbar puncture (LP) in patients with suspected subarachnoid hemorrhage (SAH) and normal neurological examinations. These authors retrospectively reviewed records of 73 patients with final diagnoses of spontaneous SAH who underwent CT after presenting with sudden-onset severe headaches and normal neurological examinations.

Two neuroradiologists who were blinded to patient outcomes and original CT interpretations reviewed the scans for evidence of herniation or midline shift >2 mm. The radiologists agreed that brain herniation or midline shift was present in 4 of the 73 cases (5%); only 1 of these cases was identified in the initial radiology report. The radiologists disagreed with each other about the presence of herniation or shift in 4 cases (5%); in all 4 cases, CT scan results were considered negative for herniation or shift in the initial report.

Comment: The authors' recommendation that CT be routinely performed before LP in patients with suspected SAH is overreaching, given their study's limitations. However, new-generation CT scanning picks up most cases of SAH noninvasively, so the best approach is to obtain a CT scan first and follow with LP if the scan result is negative.

—
Diane M. Birnbaumer, MD, FACEP
Published in Journal Watch Emergency Medicine April 23, 2010

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Citation(s):
Baraff LJ et al. Prevalence of herniation and intracranial shift on cranial tomography in patients with subarachnoid hemorrhage and a normal neurologic examination. Acad Emerg Med 2010 Apr; 17:423.

Abstract

OBJECTIVES: Patients frequently present to the emergency department (ED) with headache. Those with sudden severe headache are often evaluated for spontaneous subarachnoid hemorrhage (SAH) with noncontrast cranial computed tomography (CT) followed by lumbar puncture (LP). The authors postulated that in patients without neurologic symptoms or signs, physicians could forgo noncontrast cranial CT and proceed directly to LP. The authors sought to define the safety of this option by having senior neuroradiologists rereview all cranial CTs in a group of such patients for evidence of brain herniation or midline shift.

METHODS: This was a retrospective study that included all patients with a normal neurologic examination and nontraumatic SAH diagnosed by CT presenting to a tertiary care medical center from August 1, 2001, to December 31, 2004. Two neuroradiologists, blinded to clinical information and outcomes, rereviewed the initial ED head CT for evidence of herniation or midline shift.

RESULTS: Of the 172 patients who presented to the ED with spontaneous SAH diagnoses by cranial CT, 78 had normal neurologic examinations. Of these, 73 had initial ED CTs available for review. Four of the 73 (5%; 95% confidence interval [CI] = 2% to 13%) had evidence of brain herniation or midline shift, including three (4%; 95% CI = 1% to 12%) with herniation. In only one of these patients was herniation or shift noted on the initial radiology report.

CONCLUSIONS: Awake and alert patients with a normal neurologic examination and SAH may have brain herniation and/or midline shift. Therefore, cranial CT should be obtained before LP in all patients with suspected SAH.
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【EBM】App 做 CT 不必打顯影劑

2010-03-26T03:57:00.000-07:00

http://www.annemergmed.com/article/S0196-0644(09)01140-8/abstract

Study objective
We seek to determine the diagnostic test characteristics of noncontrast computed tomography(CT) for appendicitis in the adult emergency department (ED) population.
Methods
We conducted a search of MEDLINE, EMBASE, the Cochrane Library, and the bibliographies of previous systematic reviews. Included studies assessed the diagnostic accuracy of noncontrast CT for acute appendicitis in adults by using the final diagnosis at surgery or follow-up at a minimum of 2 weeks as the reference standard. Studies were included only if the CT was completed using a multislice helical scanner. Two authors independently conducted the relevance screen of titles and abstracts, selected studies for the final inclusion, extracted data, and assessed study quality. Consensus was reached by conference, and any disagreements were adjudicated by a third reviewer. Unenhanced CT test performance was assessed with summary
receiver operating characteristic curve analysis, with independently pooled sensitivity and specificity values across studies.
Results
The search yielded 1,258 publications; 7 studies met the inclusion criteria and provided a sample of 1,060 patients. The included studies were of high methodological quality with respect to appropriate patient spectrum and reference standard. Our pooled estimates for sensitivity and specificity were 92.7% (95% confidence interval 89.5% to 95.0%) and 96.1% (95% confidence interval 94.2% to 97.5%), respectively; the positive likelihood ratio=24 and the negative likelihood ratio=0.08.
Conclusion
We found the diagnostic accuracy of noncontrast CT for the diagnosis of acute appendicitis in the adult population to be adequate for clinical decision making in the ED setting.

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Annals of emergency medicine Volume 55, Issue 1, Pages 51-59.e1

Vertebral osteomyelitis

2010-03-18T22:02:00.000-07:00

Vertebral osteomyelitis can be complicated by direct seeding in different compartments, resulting in paravertebral, epidural, or psoas abscesses. In one series, vertebral osteomyelitis was complicated by epidural abscess in 17% of cases, paravertebral abscess in 26%, and a disk-space abscess in 5%. One fourth of patients developed motor weakness or paralysis, with particularly high rates among patients with cervical spine osteomyelitis. Neurologic complications have been reported in 38% of patients with vertebral osteomyelitis. In an analysis of 14 case series, vertebral osteomyelitis was complicated by relapse in 8% of cases, and death in 6%.

What organisms are most frequently implicated in pyogenic vertebral osteomyelitis?
Staphylococcus aureus is the most common microorganism implicated in pyogenic vertebral osteomyelitis, followed by E. coli. Coagulase-negative staphylococci and Propionibacterium acnes cause almost exclusively exogenous osteomyelitis after spine surgery, particularly if fixation devices are used. However, in case of prolonged bacteremia (e.g., pacemaker-electrode associated infection), hematogenous vertebral osteomyelitis due to low-virulence microorganisms (e,g., coagulase-negative staphylococci) has been described.

What tests are highly sensitive for the diagnosis of vertebral osteomyelitis?
Increased CRP is highly sensitive for the diagnosis of osteomyelitis, reported in 100% of cases. CRP is the preferred marker of infection, at least in postoperative spinal wound infection. Increased blood leukocyte counts or a high percentage of neutrophils (above 80%) are insensitive for the diagnosis of osteomyelitis. In a systematic review of studies of vertebral osteomyelitis, positive blood cultures were reported in 58% (range across studies, 30 to 78%).

What diagnostic step is recommended if vertebral osteomyelitis is suspected by imaging procedures and blood cultures show no growth?
If vertebral osteomyelitis is suspected by imaging procedures and blood cultures do not show growth, biopsy is generally warranted. Biopsy should be performed regardless of whether or not blood cultures are negative if polymicrobial osteomyelitis is suspected (e.g., intraabdominal sepsis). If the patient has a paravertebral, epidural, or psoas abscess, CT-guided drainage (with stain and culture of the specimen) may make bone biopsy unnecessary. Culture of a biopsy specimen, either CT-guided or open, has a higher overall yield than blood cultures (77%, range across studies 47 to 100%). Bone samples should be cultured for aerobic and anaerobic bacteria and for fungi. In patients with a suggestive history (e.g., stay in endemic region, subacute presentation), cultures should also be performed for mycobacteria and brucella species. In addition, analysis by histopathology is useful, because the presence of leukocytes in the specimens distinguishes infection from contamination.

EtCO2 已是 standard of care？

2010-03-12T20:25:00.000-08:00

Does Capnography Add Benefit During Emergency Department Propofol Sedation?
All patients who became hypoxemic demonstrated respiratory depression by capnography before developing hypoxemia.

Capnography has been used as a real-time adjunct to procedural sedation monitoring in intensive care units and operating rooms for decades, yet it is not commonly used in the emergency department (ED) for this purpose. These authors determined whether adding capnography to standard monitoring (pulse oximetry, pulse rate, and blood pressure) during ED procedural sedation decreases the incidence of hypoxic events. In a prospective trial, 132 consecutive adults undergoing propofol sedation with standard monitoring and capnography at a single tertiary-care hospital ED were randomized to a study group, in which treating physicians could view the capnography monitoring screen, or to a control group, in which physicians could not view the screen.

Procedural sedation was initiated with a bolus of 1 mg/kg of propofol, followed by additional boluses of 0.5 mg/kg. All patients received opioids (0.5 µg/kg of fentanyl or 0.05 mg/kg of morphine) at least 30 minutes before administration of propofol. Hypoxia was defined as a pulse oximetry oxygen saturation (SpO2) level <93%.>/= 50 mm Hg, an ETCO2 absolute increase or decrease from baseline of >/= 10%, or loss of the waveform for >/= 15 seconds.

Patient characteristics were similar in the two groups. The rate of capnography-detected respiratory depression was similar between groups, but hypoxia was more frequent in the control group (42% vs. 25%). Capnographic evidence of respiratory depression was 100% sensitive for predicting hypoxia. Overall, 64% of patients with capnographic evidence of respiratory depression developed hypoxia.

Comment:
This study and myriad others from the anesthesia and intensive care literature provide convincing evidence that capnography is extremely useful for detecting respiratory depression and preventing hypoxia in patients undergoing procedural sedation. Its use should be standard for emergency department patients receiving deep procedural sedation.

—
Richard D. Zane, MD, FAAEM
Published in Journal Watch Emergency Medicine March 12, 2010
Citation(s): Deitch K et al. Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial. Ann Emerg Med 2010 Mar; 55:258.

commotio cordis

2010-03-10T22:32:00.000-08:00

Ventricular fibrillation and sudden death triggered by a blunt, nonpenetrating, and often innocent-appearing unintentional blow to the chest without damage to the ribs, sternum, or heart (and in the absence of underlying cardiovascular disease) constitute an event known as commotio cordis.

When does commotio cordis occur?
About 55% of occurrences of commotio cordis have been reported in young competitive athletes (mostly those between 11 and 20 years of age) participating in a variety of organized amateur sports — typically baseball, softball, ice hockey, football, or lacrosse — who receive a blow to the chest that is usually (but not always) delivered by a projectile that is used to play the game.

How should suspected commotio cordis be treated?
A public health strategy that incorporates a plan for making automated external defibrillators (AEDs) widely available is likely to result in the survival of more young people in the event of commotio cordis. Indeed, AEDs have also effectively terminated ventricular fibrillation in animal models of commotio cordis. However, even under optimal conditions, an AED can fail to restore the heart to normal rhythm after commotio cordis. Both clinical studies and experimental studies suggest that precordial thumps are unreliable in terminating ventricular fibrillation caused by chest blows.

What location of a blow can precipitate commotio cordis?
To precipitate commotio cordis, the blow must be directly over the heart, particularly at or near the center of the cardiac silhouette. Precordial bruises representing the imprint of a blow are frequently evident in victims. There is no evidence in humans or in experimental models that blows sustained outside the precordium (e.g., the back, the flank, or the right side of the chest) cause sudden death.

At what part of the cardiac electrophysiological cycle must the blow occur?
The blow must occur within a narrow window of 10 to 20 msec on the upstroke of the T wave, just before its peak (accounting for only 1% of the cardiac cycle) — that is, the blow must occur during an electrically vulnerable period, when inhomogeneous dispersion of repolarization is greatest, creating a susceptible myocardial substrate for provoked ventricular fibrillation.

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Teaching topics from the New England Journal of Medicine
Vol. 362, No.10, March 11, 2010

18歲以下之OHCA：不能只做壓胸之CPR

2010-03-06T02:25:00.000-08:00

Conventional Cardiopulmonary Resuscitation Is Better Than Compression-Only CPR for Children with Noncardiac Causes of Arrest
Among patients aged 1–17 years with primary cardiac arrest, conventional CPR and compression-only CPR similarly improved outcomes over no bystander CPR, but for children with noncardiac causes of arrest, conventional CPR was better.

Compression-only cardiopulmonary resuscitation (CPR) has been shown to be as effective as conventional CPR for adults, in whom most arrests are of primary cardiac origin (JW Emerg Med Mar 30 2007), but is compression-only CPR useful for children, who are much more likely to arrest from respiratory causes? Researchers in Japan analyzed data from a nationwide, prospective observational database for 5170 children (age, 17 years) with out-of-hospital cardiac arrest (71% noncardiac etiology, 29% cardiac etiology). Bystander CPR was provided to 47% of children; 30% received conventional CPR, and 17% received chest compressions only without rescue breathing.

The primary endpoint was favorable neurological outcome (defined as Glasgow-Pittsburgh cerebral performance category 1 or 2) 1 month after arrest. Multiple logistic regression analysis revealed that favorable neurological outcome was significantly more likely for children who received bystander CPR than for those who did not (4.5% vs. 1.9%), for patients aged 1–17 years than for infants younger than 1 year (4.1% vs. 1.7%), for those with ventricular fibrillation as the initial rhythm than for those with other rhythms (20.6% vs. 2.3%), and for those with witnessed arrest (by family or others) than for those with unwitnessed arrest (6.7% and 10.3%, respectively, vs. 1.3%). In children aged 1–17 years, rates of favorable neurological outcome were significantly higher with conventional CPR than with compression-only CPR among patients with noncardiac causes of arrest (7.2% vs. 1.6%), but rates did not differ by type of CPR among patients with cardiac causes of arrest. Neurological outcomes were poor in infants (age, <1 year), regardless of type of CPR or etiology of arrest.

Comment:
Bystander CPR, particularly for witnessed arrest, greatly improves meaningful survival in adults and children. Compression-only CPR is a reasonable alternative for adults and might increase the likelihood that CPR is performed. However, children's arrests are usually from noncardiac causes, and conventional CPR clearly is superior to compression-only CPR in such cases. For a bystander, determining a cardiac versus a noncardiac cause for an arrest is almost impossible, so the recommendation is clear: Conventional CPR for children up to age 17!

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine March 2, 2010

CITATION(S):
Kitamura T et al. Conventional and chest-compression-only cardiopulmonary resuscitation by bystanders for children who have out-of-hospital cardiac arrests: A prospective, nationwide, population-based cohort study. Lancet 2010 Mar 3; [e-pub ahead of print]. (http://dx.doi.org/10.1016/S0140-6736(10)60064-5)
López-Herce J and Álvarez AC. Bystander CPR for paediatric out-of-hospital cardiac arrest. Lancet 2010 Mar 3; [e-pub ahead of print]. (http://dx.doi.org/10.1016/S0140-6736(10)60316-9)

休克治療：dopamine...可以被norepinephrine取代了！？

2010-03-06T02:17:00.000-08:00

Dopamine vs. Norepinephrine in Treatment of Shock
A large randomized trial shows no difference in death rates with the two agents overall but significantly higher mortality with dopamine among patients with cardiogenic shock.

When fluid therapy is not successful in reversing a shock state, adrenergic agents are used, most commonly dopamine or norepinephrine. These agents differ in their modes of action, as they affect -adrenergic and β-adrenergic receptors differently. Observational studies have shown higher death rates with dopamine than with norepinephrine in patients with shock; the few randomized trials to date have been too small to provide meaningful data.

In the current multicenter European study, 1679 adult patients with shock (signs of tissue hypoperfusion and systolic blood pressure <100 mm Hg or mean arterial pressure <70 mm Hg) that persisted after treatment with "adequate" fluids (at least 1000 mL of crystalloids or 500 mL of colloids) were randomized to receive dopamine or norepinephrine. Patients who had already received vasopressors for more than 4 hours were excluded. Treating physicians were blinded to drug assignment. Patients with hypovolemic shock, cardiogenic shock, and septic shock were included. The primary endpoint was the rate of death at 28 days. Secondary endpoints included time to hemodynamic stability and incidence of adverse events, such as serious arrhythmias and myocardial necrosis.

Rates of death at 28 days and times to hemodynamic stability did not differ significantly between the dopamine and norepinephrine groups. However, significantly more patients in the dopamine group than in the norepinephrine group experienced arrhythmias (24% vs. 12%). A predefined subgroup analysis according to type of shock showed that among 280 patients with cardiogenic shock, the death rate at 28 days was significantly higher in dopamine recipients than in norepinephrine recipients. An editorialist notes the relatively low amount of fluids considered by the investigators to be adequate to gauge response before starting vasopressors.
Comment: The authors "strongly challenge" the current American College of Cardiology–American Heart Association guidelines that recommend dopamine as a first-line agent for cardiogenic shock. In such cases, norepinephrine seems to be the prudent choice. No evidence supports one agent over the other for different forms of shock.

—
J. Stephen Bohan, MD, MS, FACP, FACEP

Gastroesophageal varices

2010-03-05T04:10:00.000-08:00

Gastroesophageal varices are present in almost half of patients with cirrhosis at the time of diagnosis, with the highest rate among patients with Child–Turcotte–Pugh class B or C disease. The 1-year rate of recurrent variceal hemorrhage is approximately 60%. The 6-week mortality with each episode of variceal hemorrhage is approximately 15 to 20%.

How should acute variceal hemorrhage be treated in patients with compensated cirrhosis?
Patients who have Child class A or B disease or who have an hepatic venous pressure gradient (HVPG) of less than 20 mm Hg have a low or intermediate risk and should receive standard therapy — specifically, the combination of a vasoconstrictor (terlipressin, somatostatin, or analogues, administered from the time of admission and maintained for 2 to 5 days) and endoscopic therapy (preferably endoscopic variceal ligation, performed at diagnostic endoscopy less than 12 hours after admission), together with short-term prophylactic antibiotics (either norfloxacin or ceftriaxone). Placement of a transjugular intrahepatic portosystemic shunt is currently considered a salvage therapy for the 10 to 20% of patients in whom standard medical therapy fails. What treatments should be used to prevent recurrent variceal hemorrhage?
Given the high recurrence rate, patients who survive an acute variceal hemorrhage should receive therapy to prevent recurrence before they are discharged from the hospital. Combination pharmacologic therapy (nonselective beta-blockers such as propranolol or nadolol plus nitrates) or combination endoscopic variceal ligation plus drug therapy are warranted because of the high risk of recurrence, even though the side effects will be greater than those with single-agent therapy (recommended for primary prophylaxis).

Should patients with cirrhosis but without varices be treated with non-selective beta-blockers for primary prophylaxis?
A: Patients without gastroesophageal varices or with gastroesophageal varices that have never bled are at relatively low risk for bleeding and death; therefore, therapies for these patients should be the least invasive. In patients without varices, treatment with nonselective beta-blockers is not recommended because they do not prevent the development of varices and are associated with side effects.

In patients with cirrhosis without varices, which one of the following measurements is the best method to stratify risk?
A: In patients without varices and in those with variceal hemorrhage, measurement of portal pressure with the use of the HVPG is the best method to stratify risk. Portal hypertension is present when the HVPG is greater than 5 mm Hg, but it is considered clinically significant when the HVPG is greater than 10 mm Hg, because in patients without varices, this pressure is the strongest predictor of the development of varices, clinical decompensation, and hepatocellular carcinoma. The HVPG is obtained by means of catheterization of a hepatic vein with a balloon catheter through a jugular or femoral vein.

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Teaching topics from the New England Journal of Medicine - Vol. 362, No. 9, March 4, 2010

以Lactate取代ScvO2

2010-02-26T18:47:00.000-08:00

Lactate Clearance Measures Efficacy of Goal-Directed Therapy in Sepsis
Mortality did not differ significantly when lactate clearance or central venous oxygen saturation was used to measure tissue oxygen delivery.

Goal-directed resuscitation for severe sepsis focuses on three targets: (1) fluid resuscitation to a central venous pressure of 8–12 mm Hg, (2) pressure support to a mean arterial pressure of at least 65 mm Hg, and (3) adequate oxygen delivery (via blood transfusion, dobutamine infusion, or both) to central venous oxygen saturation (ScvO2) of at least 70%. Measurement of ScvO2, however, requires a special catheter. These authors tested the hypothesis that use of lactate clearance >10% is not inferior to use of ScvO2 70% for assessing the adequacy of oxygen delivery.

In a prospective study conducted at the emergency departments of three U.S. medical centers, 300 patients with severe sepsis and septic shock were randomized to resuscitation to a target central venous pressure of 8–12 mm Hg, mean arterial pressure of >65 mm Hg, and either ScvO2 70% or lactate clearance >10% at 2 hours after initiation of resuscitation. The primary outcome was absolute in-hospital mortality. Overall, 23% of patients in the ScvO2 group died, compared with 17% in the lactate clearance group; the 6% difference between groups did not reach the predetermined statistical threshold of a 10% difference. Rates of adverse events were similar between groups.

Comment:
Early goal-directed therapy in patients with sepsis reportedly decreases mortality by as much as 46%, but the need for a special catheter to measure ScvO2 can be an obstacle to its implementation. This study's findings suggest that a serum lactate decrease of 10% within 2 hours after initiation of sepsis resuscitation is not inferior to an ScvO2 of 70% for measuring adequate oxygen delivery and that lactate measurement might substitute for ScvO2 measurement.

—
Diane M. Birnbaumer, MD, FACEP
Dr. Birnbaumer works in the same department as Dr. Lewis, the editorialist. However, Dr. Lewis did not participate in Dr. Birnbaumer's coverage of this article.
Published in Journal Watch Emergency Medicine February 26, 2010

Citation(s):
Jones AE et al. Lactate clearance vs central venous oxygen saturation as goals of early sepsis therapy: A randomized clinical trial. JAMA 2010 Feb 24; 303:739.
Lewis RJ. Disassembling goal-directed therapy for sepsis: A first step. JAMA 2010 Feb 24; 303:777.

Scabies 之治療

2010-02-26T03:31:00.000-08:00

What is the best approach for treating classical scabies?
For classical scabies, the authors recommend two applications of topical permethrin 5% — one on day 1 and one between day 8 and day 15. The drug should be applied in the evening and left on overnight. Two doses of oral ivermectin (200 µg/kg/dose), taken with food — one on day 1 and one between day 8 and day 15 is an alternative strategy.

When should ivermectin be used to treat scabies?
Ivermectin should be used in combination with topical permethrin 5% to treat crusted scabies. Ivermectin can also be used as a single dose to treat close contacts, or as an alternative to permethrin treatment in patients with classical scabies. Ivermectin is not approved for this indication by the Food and Drug Administration.

How should pregnant women with scabies be treated?
Topical 5% permethrin can be administered to pregnant women. It is recommended that ivermectin and lindane not be used during pregnancy.

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NEJM.org

何謂 scabies？

2010-02-26T03:30:00.000-08:00

Scabies is an ectoparasitic infection caused in humans by the scabies mite Sarcoptes scabiei variety hominis. Infection occurs as a result of direct skin-to-skin contact; fomite transmission from mites attached to clothing, bedding, and towels is uncommon. It is endemic in many impoverished communities.

What anatomical locations are most frequently affected by scabies?
In its classic presentation, lesions of scabies are most often present on the interdigital finger webs and flexor surfaces of the wrists. Elbows, axillae, buttocks, and genitalia are quite frequently involved as well, as are the breast areolae in women. Atypical presentations such as involvement of the scalp can occur in infants and the elderly.

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NEJM.org

簡單步驟減少院內感染

2010-02-23T20:04:00.000-08:00

Simple Measures Can Cut Catheter-Related Bloodstream Infections Significantly
Thousands of infections and deaths could be prevented.

Catheter-related bloodstream infections cause tens of thousands of deaths each year, and each infection costs tens of thousands of dollars to treat. In an earlier Michigan initiative (JW Gen Med Dec 27 2006) that involved 103 intensive care units (ICUs), rates of these infections were lowered dramatically after systematic implementation of five evidence-based interventions: washing hands, using full barrier precautions, cleaning the skin with chlorhexidine, avoiding the femoral site, and removing unnecessary catheters. Eighteen months after implementation, catheter-related bloodstream infections were reduced by two thirds from baseline. In this follow-up study that involved 90 of the original ICUs, investigators evaluated whether the lower incidence of such infections were sustained at 19 to 36 months after implementation (sustainability period).

Overall, data related to more than 1500 ICU months and 300,000 catheter-days during the sustainability period were reported. The mean rate of catheter-related bloodstream infections decreased from 7.7 per 1000 catheter-days at baseline to 1.3 per 1000 catheter-days at 16–18 months and to 1.1 per 1000 catheter-days at 34–36 months postimplementation. Compared with the baseline rate, mean bloodstream infection rates at 16–18 months and 34–36 months were significantly lower.

Comment:
Implementing five simple evidence-based interventions significantly lowers catheter-related bloodstream infections. These results are sustainable after such interventions are integrated into practice. As the authors conclude, widespread implementation of these interventions could lower morbidity and costs associated with these infections substantially.

—
Paul S. Mueller, MD, MPH, FACP
Published in Journal Watch General Medicine February 23, 2010
Citation(s): Pronovost PJ et al. Sustaining reductions in catheter related bloodstream infections in Michigan intensive care units: Observational study. BMJ 2010 Feb 4; 340:c309. (http://dx.doi.org/10.1136/bmj.c309)

原來肌肉放鬆藥物也可能只是味素藥...

2010-02-05T20:59:00.000-08:00

Muscle Relaxant Adds No Benefit to Ibuprofen for Cervical Strain
Pain relief did not differ among patients who received ibuprofen, cyclobenzaprine, or both drugs.

Muscle relaxants often are prescribed for neck and back pain, despite the lack of evidence of benefit. Researchers evaluated the effect of cyclobenzaprine in a prospective, randomized, double-blind study in a convenience sample of 61 adult patients (mean age, 34; 58% women) who presented to a level I trauma center emergency department with acute cervical strain (87% caused by motor vehicle collisions). Patients received ibuprofen (800 mg), cyclobenzaprine (5 mg), or both drugs three times daily for up to 7 days, as needed for pain. All patients received an initial dose of 800 mg of ibuprofen in the ED.

Patients rated pain severity on a 100-mm visual analog scale 30 to 60 minutes after taking the morning dose of medication. Pain scores improved significantly over 7 days in all three groups and did not differ among groups. Adverse effects were minimal and included dizziness in four patients who received cyclobenzaprine alone or with ibuprofen and nausea in one patient who received ibuprofen alone.

Comment:
A small dose of cyclobenzaprine was used in this study, perhaps to avoid the anticholinergic, antihistaminic, and sedative side effects of this drug, which is closely related chemically to tricyclic antidepressants. No convincing evidence supports the use of cyclobenzaprine in painful musculoskeletal conditions, and the drug's benefit-to-adverse effect profile therefore argues against prescribing it. Most patients with cervical strain will get better. Provide adequate analgesia as needed, and leave the cyclobenzaprine in the pharmacy.

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine February 5, 2010

Citation(s): Khwaja SM et al. Comparison of ibuprofen, cyclobenzaprine or both in patients with acute cervical strain: A randomized controlled trial. CJEM 2010 Jan; 12:39.

Septic Shock, Insulin, and Steroids

2010-02-04T20:51:00.000-08:00

Intensive insulin therapy did not lower in-hospital mortality in septic shock patients who received hydrocortisone.

In a study published in 2002, patients with septic shock and impaired adrenal reserve appeared to benefit from 7-day courses of hydrocortisone (50 mg every 6 hours) plus the mineralocorticoid fludrocortisone (JW Gen Med Aug 30 2002). In contrast, hydrocortisone alone was not beneficial in the 2008 CORTICUS trial (JW Gen Med Jan 9 2008). Because patients in the 2002 trial were sicker and were treated earlier than those in CORTICUS, some experts still recommend low-dose hydrocortisone for patients with severe sepsis and refractory hypotension.
That hydrocortisone invariably induces hyperglycemia raises another question: Is intensive insulin therapy appropriate for hydrocortisone-treated patients with septic shock? To answer this question, researchers in France randomized 509 such patients to receive either intensive insulin therapy (target glucose level, 80–110 mg/dL) or usual care (target glucose level, around 150 mg/dL). In addition, to examine whether mineralocorticoid therapy is beneficial, the researchers randomized the same patients to receive or not to receive fludrocortisone in a 2x2 factorial design. The outcome: Overall in-hospital mortality was 44%; neither intensive insulin nor fludrocortisone lowered mortality or any of numerous secondary endpoints.

Comment:
In this multicenter study of hydrocortisone-treated patients with septic shock, intensive insulin therapy did not improve outcomes. An editorialist notes that (1) mean glucose levels in intensively treated patients fell short of the intended target, reaching only about 120 mg/dL, which was not markedly different from the mean glucose level (about 150 mg/dL) of the control group; and (2) the trial was underpowered to identify small differences in mortality. Thus, she calls for a much larger trial. My own sense, however, is that intensive glycemic control is not the magic bullet that will improve outcomes in septic shock patients and that research should be directed toward other pathophysiologic mechanisms.

—
Allan S. Brett, MD
Published in Journal Watch General Medicine February 4, 2010

Citation(s):
The COIITSS Study Investigators. Corticosteroid treatment and intensive insulin therapy for septic shock in adults: A randomized controlled trial. JAMA 2010 Jan 27; 303:341.
Van den Berghe G. Should glucocorticoid-induced hyperglycemia be treated in patients with septic shock? JAMA 2010 Jan 27; 303:365.

Jet Lag

2010-02-03T20:44:00.000-08:00

Jet lag is a recognized sleep disorder that results from crossing time zones too rapidly for the circadian clock to keep pace. The pathophysiology involves a temporary misalignment between the circadian clock and local time.

How can the circadian rhythm be re-entrained after travel?
A traveler may be able to accelerate re-entrainment of the circadian rhythm by intentionally seeking out bright light at the optimal times of the day. A simple recommendation for travel across six to eight time zones is to seek exposure to bright light in the morning after eastward travel and in the evening after westward travel. It may also be useful to avoid light when exposure would impede adaptation; for example, it may be helpful for a traveler to stay indoors for the first few hours of daylight after long eastward flights or for a few hours before dusk after long westward flights. The timing of sleep does not, in itself, reset the clock.

How should sleep be strategically scheduled after travel?
Shifting one's sleep schedule by 1 or 2 hours towards congruence with the destination time zone before departure may shorten the duration of jet lag. Most travelers will be sleep-deprived after an overnight flight and will require extra (recovery) sleep on the first day or two after arrival. On subsequent days, short naps are effective in reducing daytime sleepiness, whereas longer daytime naps can undermine nighttime sleep, as well as reduce exposure to the re-entraining effects of light.

How should melatonin be used?
Melatonin can be considered to be a darkness signal. To promote shifting of the body clock to an earlier time after eastward travel, the author suggests that the traveler take 0.5–3 mg of melatonin at local bedtime nightly until he or she has become adapted to local time. For westbound travel, the author suggests taking 0.5 mg (low, short-acting dose) during the second half of the night until the traveler has become adapted to local time. Melatonin is not approved as a drug by the Food and Drug Administration (FDA).

Which hypnotics are most appropriate for use during flight?
Because there is limited opportunity to sleep during a flight, a hypnotic medication that has only a 2- to 3-hour duration of action (e.g., zaleplon) is preferred. A longer-acting sleeping pill (e.g., zolpidem or eszopiclone) could result in grogginess on arrival; a sleeping pill should not be taken if there is a risk of deep-vein thrombosis because the induced sleep may further increase that risk, and it should not be combined with alcohol.

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Teaching topics from the New England Journal of Medicine - Vol. 362, No. 5, February 4, 2010

穿刺傷病患到院前不宜浪費時間做脊椎固定術

2010-01-29T17:58:00.000-08:00

Spine Immobilization for Penetrating Trauma Can Be Harmful
Patients who underwent immobilization were twice as likely to die as those who did not.

Despite a lack of supportive evidence for the practice, prehospital providers often apply spine immobilization to patients who have penetrating trauma to the head, neck, or torso without neurological symptoms or deficit. These authors retrospectively assessed the effect of prehospital spine immobilization on mortality in patients with penetrating trauma using data from the American College of Surgeons National Trauma Data Bank between 2001 and 2004.
Of 45,284 patients (median age, 29), 4.3% received cervical collars, spinal backboards, or both. The overall mortality rate was 8.1%. Multiple logistic regression analysis that controlled for confounders, including Injury Severity Score and Revised Trauma Score, showed that immobilized patients had significantly increased mortality (odds ratio, 2.06); this finding held true in subgroups of patients with gunshot wounds (OR, 2.12), hypotension (OR, 2.42), and gunshot wounds and hypotension (OR, 3.19). Complete data on in-hospital procedures were available for about 31,000 patients. Only 30 patients (0.1%) underwent operative spine stabilizing procedures for incomplete spinal-cord injury. The number needed to treat with spine immobilization to potentially benefit 1 patient was 1032. The number needed to harm with spine immobilization to potentially contribute to 1 death was 66.

Comment:
Increasing evidence indicates that limited intervention at the scene allows trauma patients to receive definitive care at a trauma center more rapidly. This study indicates that prehospital spine immobilization is associated with increased mortality in patients with penetrating trauma. Trying to assign cause and effect in a retrospective study is risky, but possibly increased scene time or interference with later care (e.g., intubation, radiography, examination of the patient's back) contribute to worse outcomes. Spine immobilization might be applied more wisely to patients with altered mental status, spine tenderness, or sensorimotor dysfunction.

—
John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine January 29, 2010
Citation(s): Haut ER et al. Spine immobilization in penetrating trauma: More harm than good? J Trauma 2010 Jan; 68:115.

CT Radiation Exposure and Cancer

2010-01-22T18:40:00.000-08:00

Radiation from CT scans might cause 2% of future cancers.
An estimated 72 million computed tomography (CT) scans were performed in the U.S. in 2007. Two research groups assessed radiation dose from CT scans and future cancer risk.

Smith-Bindman and colleagues studied CT scans performed at four hospitals (private and public, large and small) in San Francisco in 2008. For each of 11 types of CT studies, the researchers estimated the effective dose of radiation, which takes into account "the amount of radiation to the exposed organs and each organ's sensitivity to developing cancer from radiation exposure."

The effective dose varied widely both within and between institutions for each type of CT study. The median effective dose was 2 millisieverts (mSv) for a noncontrast head CT scan and 31 mSv for an abdomen-pelvis study. For comparison, the effective dose is 0.065 mSv from posteroanterior and lateral chest radiography and 0.42 mSv from conventional mammography.

The authors estimated that a coronary angiogram delivers radiation to the breast equivalent to 15 mammograms and to the lung equivalent to 711 chest x-rays. The lag time between exposure and cancer development makes exposure potentially riskier for younger than older patients; the authors estimated that 1 in every 270 women who undergo coronary CT angiography at age 40 will develop cancer.

Berrington de Gonzalez and colleagues used a national database to estimate age-specific cancer risks from CT studies performed in the U.S. in 2007. CT scans performed during the last 5 years of life or after a diagnosis of cancer were excluded from the analysis. Thirty percent of CT scans were performed on patients aged 35 to 54. The authors predict that 2% (29,000) of future cancers will be caused by CT scans performed in 2007, and they estimate a cancer mortality rate of 50%.

Comment:
An editorialist terms these numbers "eye opening" and calls for dose standardization, patient education, and test ordering guidelines. A recent government report shows an eightfold difference in test ordering across states, with no detectable mortality benefit from higher rates of testing. One approach to limiting radiation exposure is to display patients' historical cumulative radiation dose in electronic order entry systems. It is time for someone to shout "stop."

—
J. Stephen Bohan, MD, MS, FACP, FACEP
Published in Journal Watch Emergency Medicine January 22, 2010

Citation(s): Smith-Bindman R et al. Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer. Arch Intern Med 2009 Dec 14/28; 169:2078.

Heart Failure

2010-01-21T23:55:00.000-08:00

Which patients with heart failure should be treated with angiotensin-converting–enzyme (ACE) inhibitors?
ACE inhibitors are the first-line therapy for patients with systolic heart failure; therapy should be initiated promptly after diagnosis and continued indefinitely. ACE inhibitors increase the ejection fraction modestly and reduce ventricular size, symptoms, hospitalization, and overall mortality. ACE inhibitors also reduce the risk of myocardial infarction.

When should spironolactone be used in patients with heart failure?
In a large, placebo-controlled, randomized trial in which patients received spironolactone in addition to a diuretic, digoxin, and an ACE inhibitor, a reduction in symptoms and in hospital admissions, and a 30% reduction in mortality, were seen among patients with severe systolic heart failure (NYHA class III or IV). Therefore, the addition of an aldosterone antagonist should be considered for any patient who remains in NYHA class III or IV, despite treatment with a diuretic, an ACE inhibitor (or angiotensin-receptor blocker [ARB]), and a beta-blocker.

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Teaching topics from the New England Journal of Medicine - Vol. 362, No. 3, January 21, 2010

What is Takotsubo cardiomyopathy?

2010-01-21T23:53:00.000-08:00

Takotsubo cardiomyopathy
Also known as transient left ventricular apical ballooning syndrome or stress cardiomyopathy. One of the hallmarks of this syndrome is that the apical ballooning is transient, typically resolving in days to weeks. Takotsubo cardiomyopathy typically arises in the context of acute emotional or physical stress. It often resembles an acute coronary syndrome. The pathognomic findings are ballooning (dilatation and akinesis) of the left ventricular apex, with compensatory hyperkinesis of the basal walls of the left ventricle. Coronary angiography reveals no obstructive coronary-artery lesions; in addition, the distribution of left ventricular dysfunction often extends beyond the distribution of a single coronary artery.

Fusobacterium necrophorum

2010-01-16T14:28:00.000-08:00

A New Culprit for Pharyngitis in Adolescents
A gram-negative anaerobe that causes Lemierre syndrome has become a common cause of pharyngitis.

Guideline recommendations for the management of pharyngitis vary from doing nothing, to treating patients with positive test results (rapid or culture), to treating empirically. Current guidelines focus on infections with group A streptococcus, because, although the disease is self-limiting, it can cause substantial complications, most notably rheumatic fever (JW Pediatr Adolesc Med Apr 1 2009).

A recent surge in complicated cases of pharyngitis, particularly in adolescents, prompted more-elaborate microbiological testing. DNA analysis revealed that the gram-negative anaerobe, Fusobacterium necrophorum, is as common as group A strep in this age group. An estimated 1 in 400 cases of F. necrophorum pharyngitis progresses to complications, including abscess, septicemia with septic pulmonary emboli, and Lemierre syndrome, which is a septic thrombophlebitis of the internal jugular vein. In case series of patients with F. necrophorum pharyngitis, death — an almost unknown complication of group A strep pharyngitis — has been reported in 2% to 5% of patients, along with a substantial morbidity rate of 10%.

The organism is not sensitive to macrolides, which are recommended for suspected strep pharyngitis in penicillin-allergic patients. Penicillin or a cephalosporin remains the first treatment choice for adolescents and young adults with pharyngitis, and the addition of clindamycin is indicated for those with evidence of sepsis or neck swelling. Clindamycin should be the primary treatment in penicillin-allergic patients.

Comment:
The differential diagnosis of pharyngitis in adolescents and young adults includes group A strep, mononucleosis, and acute HIV infection and should now also include F. necrophorum, both at initial presentation and in cases that have not resolved in the usual 5-day interval from onset. Any clinical indicator of bacteremia indicates the need for admission (at least to an observation unit), blood cultures, and antibiotic coverage for F. necrophorum pending culture results.

—
J. Stephen Bohan, MD, MS, FACP, FACEP
Published in Journal Watch Emergency Medicine January 15, 2010

Citation(s): Centor RM. Expand the pharyngitis paradigm for adolescents and young adults. Ann Intern Med 2009 Dec 1; 151:812.

Cyanide antidotes

2010-01-12T07:21:00.000-08:00

Cyanide antidotes：nitrites and sodium thiosulfate之作用機轉

The nitrites oxidize some of the hemoglobin's iron from the ferrous state to the ferric state, converting the hemoglobin into methemoglobin. (Treatment with nitrites is not innocuous as methemoglobin cannot carry oxygen, and methemoglobinemia needs to be treated in turn with methylene blue).
Cyanide preferentially bonds to methemoglobin rather than the cytochrome oxidase, converting methemoglobin into cyanmethemoglobin.
In the last step, the intravenous sodium thiosulfate converts the cyanmethemoglobin to thiocyanate, sulfite, and hemoglobin. The thiocyanate is excreted.

孕婦H1N1流感重症的特徵

2010-01-06T16:10:00.000-08:00

Severe influenza during pregnancy: which trimester?
In this large series of pregnant and postpartum patients who were hospitalized with or died from 2009 H1N1 influenza, 95% of the pregnant patients were infected in the second or third trimester. The fact that eight of the cases of influenza in this study involved a postpartum onset of symptoms, with severe disease and death in some of these cases, highlights the continued high risk immediately after pregnancy.

Should pregnant women receive the H1N1 influenza vaccine?
Pregnant women are a top-priority group for immunization against 2009 H1N1 influenza. Since the 2009 H1N1 monovalent vaccine is manufactured according to the same processes that are used for the seasonal influenza vaccine, its safety profile among pregnant women is expected to be similar to that of the seasonal influenza vaccine, which has consistently been shown to be safe during pregnancy. Preliminary results from a trial of 2009 H1N1 monovalent vaccine have shown a robust immune response in pregnant women, similar to the response in nonpregnant adults, and no safety concerns have been identified. Maternal vaccination may also provide a benefit to the newborn infant, with a decreased risk of respiratory infections related to influenza in both the mother and infant during the first 6 months after delivery.

How should pregnant women with H1N1 influenza infection be treated?
Regardless of the results of rapid antigen tests, women with suspected or confirmed influenza who are pregnant or who have delivered within the previous 2 weeks should receive aggressive antiviral treatment and undergo close monitoring. The Centers for Disease Control and Prevention (CDC) recommends prompt antiviral treatment of pregnant women with suspected or confirmed 2009 H1N1 influenza, ideally within 48 hours after symptom onset.

What underlying condition most commonly predisposed pregnant women to complications from H1N1 influenza infection?
A total of 32 of the 93 pregnant women for whom data were available (34%), 2 of the 8 postpartum women (25%), and 82 of the 137 nonpregnant women (60%) had underlying conditions besides pregnancy that placed them at increased risk for complications from influenza; the most common condition was asthma, affecting 16% of pregnant women and 28% of nonpregnant women.

---
http://content.nejm.org/cgi/content/abstract/362/1/27?query=BUL

尿毒症病患使用EPO的風險

2010-01-06T16:02:00.000-08:00

Should patients with CKD receive erythropoiesis-stimulating agents?

The use of erythropoiesis-stimulating agents results in a reduced need for blood transfusions among patients with advanced CKD and has also been associated with a reduction in left ventricular hypertrophy. However, there is increasing evidence that erythropoiesis-stimulating agents should be used cautiously.

In clinical trials higher hemoglobin levels have led to an increased risk of death, stroke cardiovascular events, and hospitalization for congestive heart failure. Though treated patients in the TREAT study needed fewer transfusions and had a modest reduction in fatigue they had no benefit in other quality-of-life measures.

---
New England Journal of Medicine - Vol. 362, No. 1, January 7, 2010

小兒發燒：ACT好還是NSAIDs好？

2009-12-22T05:46:00.000-08:00

Feverish debate
When you see a young child with a fever, what do you recommend that parents do? Give paracetamol alone, paracetamol and ibuprofen, or ibuprofen alone? This report of a high quality study of 156 children concludes that we should recommend ibuprofen alone.

Dual therapy (ibuprofen plus paracetamol) reduced fever better than paracetamol alone in the first 24 hours
But dual therapy was no better than ibuprofen alone in the first 24 hours
Ibuprofen alone was best at making the child feel better in the first 48 hours

However, a comment says that reduction of fever is of no value if the child does not feel better. Fever helps the body combat infection; antipyretics may prolong the duration of infection, without providing any reduction in fever seizures. So, "we should use ibuprofen if an antipyretic is needed (which is seldom) and not routinely combine paracetamol with ibuprofen."

---
Source: Evidence-Bases Medicine 2009;14:174

院外ACLS不須IV給藥？

2009-12-18T20:07:00.000-08:00

Do IV Meds Matter in Out-of-Hospital Cardiac Arrest?
Use of IV drugs did not affect long-term neurological outcome or survival.

Intravenous access and drug administration have long been central elements of advanced cardiac life support (ACLS) protocols despite the absence of evidence that they improve outcomes. In a randomized, controlled, nonblinded trial, 851 consecutive adult patients with out-of-hospital, nontraumatic cardiac arrest in Oslo, Norway from 2003 to 2008 were randomized to receive ACLS with IV access and drug administration (epinephrine, atropine, and amiodarone were used) or ACLS with no IV access.

In the group that received ACLS with no IV access, IV access was established within 5 minutes after return of spontaneous circulation (ROSC). In both groups, patients with ventricular fibrillation received cardiopulmonary resuscitation for 3 minutes before the first shock and between unsuccessful series of shocks. Endotracheal intubation was standard, and postresuscitation therapeutic hypothermia was instituted regardless of initial rhythm or course of arrest. Quality of CPR was determined by transthoracic impedance signals from defibrillators. The primary outcome was survival to discharge.

The rate of hospital admission for patients with ROSC was significantly higher in the group with IV access than in the group without IV access (32% vs. 21%). However, no significant differences were found between the IV-access and no-IV-access groups in rates of survival to discharge (10% and 9%), survival with favorable neurological outcome (10% and 8%), and survival at 1 year (10% and 8%). CPR was performed according to guidelines, and its quality was similar in both groups.

Comment:
This first effort to evaluate the effect of IV access and drug administration on outcomes in patients with out-of-hospital cardiac arrest, after more than 4 decades of use, yields provocative results: These long-standing interventions were not associated with improvement in long-term survival or neurological outcome. The results are in concert with those from studies in which epinephrine, atropine, and amiodarone improved short-term but not long-term outcomes compared with placebo. In addition, IV access had no negative effect on the quality of CPR. This trial begs for research targeted at novel pharmacologic therapies and should prompt the rethinking of ACLS guidelines.

—
John A. Marx, MD, FAAEM
Published in Journal Watch Emergency Medicine December 18, 2009
Citation(s): Olasveengen TM et al. Intravenous drug administration during out-of-hospital cardiac arrest: A randomized trial. JAMA 2009 Nov 25; 302:2222.

Emergency obstetric care

2009-12-09T02:27:00.000-08:00

Decision-making algorithm in emergency obstetric care.

C-section, cesarean section;

FHTs, fetal heart tones;

US, ultrasonography.

Transtubular potassium gradient (TTKG)

2009-12-08T19:26:00.000-08:00

Indications：Hyperkalemia

Precautions：

Results altered by Hyperkalemia Management.
Obtain lab sample prior to intervention if possible.
Do not delay treatment in emergent Hyperkalemia.

Labs：

Serum Potassium and Serum Osmolality.
Spot urine for Urine Potassium and Urine Osmolality.

Formula of Transtubular Potassium Gradient (TTPG)：

TTPG = (Urine K+ x Serum Osm)/(Serum K+ x Urine Osm)
... where K+ is potassium and Osm is Osmolality.

Interpretation of Fractional Excretion of Potassium：

TTPG <6-8%:>
TTPG). TTPG >6-8: Extrarenal cause of Hyperkalemia (May also be increased in Chronic Renal Failure).

【新藥】Dabigatran有可能取代warfarin？！

2009-12-08T19:10:00.000-08:00

Oral Alternative to Warfarin for Venous Thromboembolism?
Dabigatran was safe and effective and had advantages over warfarin.

Dabigatran is a direct oral thrombin inhibitor that, unlike warfarin, can be given in a fixed dose and requires no laboratory monitoring. In a recently published study, dabigatran compared favorably with warfarin in patients with atrial fibrillation (JW Cardiol Sep 1 2009).
In this new industry-sponsored double-blind trial, more than 2500 patients with acute venous thromboembolism (69% with deep venous thrombosis [DVT] only, 21% with pulmonary embolism only, and 10% with both) were randomized to receive either warfarin or dabigatran after initial heparin therapy. At 6 months, significant differences were found between the dabigatran and warfarin groups in incidence of recurrent venous thromboembolism (2.4% and 2.1%) or major bleeding (1.6% and 1.9%). A combined endpoint of major bleeding plus clinically relevant nonmajor bleeding occurred less often with dabigatran (5.6% vs. 8.8%). One side effect, dyspepsia, occurred more commonly with dabigatran than with warfarin (3.1% vs. 0.7%).

Comment:
Dabigatran, which is not yet FDA approved, appears to be comparable to warfarin in both efficacy and safety in patients with venous thromboembolism. Its advantage, compared with warfarin, is that it requires neither laboratory monitoring nor dose adjustments. A previous direct oral thrombin inhibitor, ximelagatran, was effective but failed to gain FDA approval because of hepatotoxicity; in contrast, no hepatotoxicity has occurred in studies of dabigatran. Note that both dabigatran and an oral direct inhibitor of factor Xa (rivaroxaban) already have been approved for use in Canada and some European countries for DVT prophylaxis following total hip or knee arthroplasty but not yet for atrial fibrillation or DVT treatment.

—
Allan S. Brett, MD
Published in Journal Watch General Medicine December 8, 2009
Citation(s): Schulman S et al. Dabigatran versus warfarin in the treatment of acute venous thromboembolism. N Engl J Med 2009 Dec 10; 361:2342.

肥鵝肝醬

2009-11-24T02:51:00.000-08:00

Foie gras
This editorial and study point out that:

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in both children and adults
It is likely to become a serious public health problem worldwide
It is closely associated with obesity and insulin resistance
It includes a spectrum of diseases from simple fatty liver (steatosis) to fibrosis and cirrhosis
This study shows it can take only 10-20 years for the disease to progress from its first signs to irreversible end-stage disease
There is no effective drug treatment - early diagnosis and lifestyle changes are key to stop disease progression
Disease markers need to be developed to identify those most at risk.

---
Source: Gut 2009;58:1442

Migraine with aura and stroke

2009-11-24T02:49:00.000-08:00

Is everyone who gets migraines at an increased risk of a stroke?
This large survey and editorial say:

Only the quarter of migraine sufferers who get an aura are at increased risk of stroke
Migraine with aura doubles a person's risk of having a stroke
Migraine is also associated with an increased risk of transient ischaemic attacks and angina. It isn't clear whether this is true for all migraine sufferers or only those with aura
Migraine without aura isn't associated with an increased risk of stroke
Aura is a transient neurological disturbance before or during the headache
Sensitivity to light, visual blurring, and fatigue are common accompaniments to migraine but should not be confused with aura
People who have migraine with aura should have their other risk factors treated (smoking, blood pressure, cholesterol, and blood glucose)

---
Source: BMJ 2009;339:b4380

解決急診爆滿床：於病房走廊加床是安全的對策

2009-11-20T21:20:00.000-08:00

Is It Safe to Admit Boarder Patients to Inpatient Hallways?
A study at a single academic ED shows that the practice is safe.

Caring for emergency department patients in hallways has become the norm as hospital crowding has become pervasive. One approach to reducing ED crowding during times of high ED and inpatient census is to augment inpatient capacity by admitting selected ED boarder patients to hallways on inpatient floors, instead of boarding them in the ED. This approach essentially "shares the pain" of hospital crowding.

In a retrospective cohort study, investigators compared outcomes for patients who were admitted to inpatient hallways with outcomes for patients who were admitted to standard inpatient beds at a single U.S. academic ED between 2004 and 2008. Patients who did not require intensive care unit (ICU) or step-down care or high-intensity nursing care for such needs as continuous suction, high-flow O2, or seizure monitoring were eligible to board in inpatient hallways.

Of 55,062 ED patients who were admitted during the study period, 4% were admitted to an inpatient hallway. ED census at time of triage was significantly higher for patients admitted to hallways compared with patients admitted to standard beds, and time from ED triage to admission was significantly longer for patients admitted to hallways. Approximately 25% of patients admitted to hallways were assigned to a standard bed immediately on arrival to the inpatient unit, 25% were placed in a room within 1 hour, and the remaining 50% waited approximately 8 hours for a room. Patients admitted to hallways, compared with those admitted to standard beds, had significantly lower rates of in-hospital mortality (1.1% vs. 2.6%) and transfer to an ICU (2.5% vs. 6.7%).

Comment:
Although inpatients in other countries are commonly boarded in inpatient hallways, this practice has met significant resistance in the U.S., with risk to patient safety cited as the major concern. At this study's single institution, boarding selected patients on inpatient units was not associated with risk to patient safety. Other institutions should consider implementing inpatient-unit boarding as part of a multifaceted approach to crowding.

—
Richard D. Zane, MD, FAAEM
Published in Journal Watch Emergency Medicine November 20, 2009
Citation(s): Viccellio A et al. The association between transfer of emergency department boarders to inpatient hallways and mortality: A 4-year experience. Ann Emerg Med 2009 Oct; 54:487.

【NEJM】H1N1 重症病人的特徵

2009-11-12T03:46:00.000-08:00

What are patient risk factors for a requirement of intensive care services in H1N1 influenza?
In the ANZIC study, infants (0 to 1 year of age), pregnant women, and adults 25 to 64 years of age appeared to be at particular risk for severe disease. Indigenous groups were overrepresented among patients who were admitted to ICUs: 10% in Australia and 25% in New Zealand. Further, both the ANZIC study and other studies indicate that obesity is a likely risk factor for increased severity of H1N1. In the ANZIC study, 29% of patients had a body-mass index (the weight in kilograms divided by the square of the height in meters) of 35 or more.

What is the risk of death after infection with the H1N1 influenza virus as compared to the risk of death after infection with seasonal influenza?
The proportion of patients who died in the ANZIC study (14%) is no higher than that previously reported among patients with seasonal influenza A who were admitted to an ICU. Patients admitted to an ICU with seasonal influenza A predominantly are elderly and have coexisting conditions. In H1N1, although older age, the presence of coexisting conditions, and a requirement for invasive ventilation were independently associated with increased risk of death in the ANZIC study, the majority of deaths occurred in younger patients because there were greater numbers of younger patients in the study cohort.

---
New England Journal of Medicine - Vol. 361, No. 20, November 12, 2009

推動OHCA 低溫治療：是時候了...

2009-11-06T22:13:00.000-08:00

Induced Hypothermia After VF Cardiac Arrest Improves Outcomes
Hypothermia led to significantly better survival rates and neurological outcomes in patients with ventricular fibrillation but not in those with other initial rhythms.

Despite evidence that induced hypothermia therapy after cardiac arrest improves neurological outcomes and survival, cooling protocols have not been widely implemented. In a retrospective observational study, researchers compared outcomes in consecutive patients with out-of-hospital cardiac arrest who were resuscitated in the 2 years before (204 patients) and the 2 years after (287) implementation of a therapeutic hypothermia protocol at a teaching hospital in Seattle. Patients with severe infection, active bleeding, or nonintact skin from recent burns or who were in a persistent vegetative state prior to cardiac arrest were excluded.
Patients in the hypothermia group were cooled with ice packs, cooling blankets, or cooling pads and received intravenous vecuronium and diazepam. Temperature was measured with an esophageal probe; the goal of 32°C–34°C was achieved in 65% of patients. Passive rewarming commenced after 24 hours of cooling.

Rates of survival to hospital discharge were significantly higher in the hypothermia group than in the control group among patients with an initial rhythm of ventricular fibrillation (VF) (54% vs. 39%) but did not differ among patients with other rhythms. Similarly, the rate of favorable neurological outcomes was significantly higher in the hypothermia group than in the control group among patients with VF (35% vs. 15%).

Comment: Although a greater incidence of witnessed arrests in the hypothermia group (66%) than in the control group (57%) might have skewed the results, the findings suggest that cardiac arrest patients with an initial rhythm of VF might benefit from therapeutic cooling. Based on this and previous outcome studies (JW Emerg Med Oct 27 2006) and on other studies showing that induced hypothermia in the emergency department is feasible (JW Emerg Med Jul 11 2008), it is time for EDs (and some emergency medical services systems) to implement hypothermia protocols for comatose survivors of cardiac arrest.

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine November 6, 2009

Citation(s): Don CW et al. Active surface cooling protocol to induce mild therapeutic hypothermia after out-of-hospital cardiac arrest: A retrospective before-and-after comparison in a single hospital. Crit Care Med 2009 Sep 16; [e-pub ahead of print]. (http://tinyurl.com/yht8qs7)

急診放射影像十戒

2009-11-02T00:21:00.000-08:00

急診放射影像十戒

【1】先問 Hx 做 PE 再照片子
【2】處置要針對病人而非針對片子
【3】沒看過病人就不要對片子下最後結論
【4】讀片要讀好片：注意明暗、解析度、大小
【5】片子要全看，不要只看部份，不要跳著看
【6】讀片有疑惑時，先重新評估病人
【7】記得〝rule of 2〞：2角度、2關節、2側、2張、2次
【8】做完 procedure 後再照一張
【9】不確定就發問
【10】建立失效安全把關機制

TPA for stroke 可延長至 4.5 小時

2009-10-29T01:15:00.000-07:00

Stroke treatment with alteplase given 3.0-4.5 h after onset of acute ischaemic stroke (ECASS III).

Conclusion:
Our results support the use of alteplase up to 4.5 h after the onset of stroke symptoms across a broad range of subgroups of patients who meet the requirements of the European product label but miss the approved treatment window of 0-3 h.

---
Lancet Neurol. 2009 Oct 20.
http://linkinghub.elsevier.com/retrieve/pii/S1474-4422(09)70264-9

HIV risk of percutaneous inoculation

2009-10-29T01:13:00.000-07:00

What is the risk of HIV transmission after percutaneous inoculation?
The overall rate of HIV transmission through percutaneous inoculation (i.e., by means of a needle or other instrument that pierces the skin) is widely reported to be 0.3% (95% confidence interval [CI], 0.2 to 0.5); features of exposure that are associated with a higher rate of transmission include a needle that was used to cannulate a blood vessel in the source patient, advanced HIV disease in the source patient, a deep needlestick, and visible blood on the surface of the instrument. Theoretically, any exposure that involves piercing of the skin may transmit infection, but clinical judgment is required to assess the likelihood that the inoculum is sufficient to pose a credible threat of transmission; many clinicians use a puncture that draws blood as a general threshold. Splashes of infectious material to mucous membranes (e.g., conjunctivae or oral mucosa) or broken skin also may transmit HIV infection (estimated risk per exposure, 0.09% [95% CI, 0.006 to 0.5]).

HIV risk of sexual exposure

2009-10-29T01:12:00.000-07:00

What is the risk of HIV transmission after sexual exposure?
The per-contact risk of HIV transmission from sexual exposure varies according to the nature of the exposure. The estimated risks are 1 to 30% with receptive anal intercourse, 0.1 to 10.0% with insertive anal intercourse and receptive vaginal intercourse, and 0.1 to 1.0% with insertive vaginal intercourse. As compared with other forms of intercourse, oral intercourse is considered to pose a lower risk of HIV transmission, although good risk estimates are lacking. The risks of sexual transmission are difficult to quantify; the wide ranges reported for the risks of per-contact transmission derive from observational studies and are influenced by many factors, including the presence or absence of concomitant genital ulcer disease, other disease states, and cervical or anal dysplasia; circumcision status; the viral load in the genital compartment; and the degree of viral virulence.

誰說OHCA低溫治療一定要買昂貴儀器？

2009-10-26T08:51:00.000-07:00

Cold saline infusion and ice packs alone are effective in inducing and maintaining therapeutic hypothermia after cardiac arrest

Aim of the study
Hypothermia treatment with cold intravenous infusion and ice packs after cardiac arrest has been described and used in clinical practice. We hypothesised that with this method a target temperature of 32–34°C could be achieved and maintained during treatment and that rewarming could be controlled.

Materials and methods
Thirty-eight patients treated with hypothermia after cardiac arrest were included in this prospective observational study. The patients were cooled with 4°C intravenous saline infusion combined with ice packs applied in the groins, axillae, and along the neck. Hypothermia treatment was maintained for 26h after cardiac arrest. It was estimated that passive rewarming would occur over a period of 8h. Body temperature was monitored continuously and recorded every 15min up to 44h after cardiac arrest.

Results
All patients reached the target temperature interval of 32–34°C within 279±185min from cardiac arrest and 216±177min from induction of cooling. In nine patients the temperature dropped to below 32°C during a period of 15min up to 2.5h, with the lowest (nadir) temperature of 31.3°C in one of the patients. The target temperature was maintained by periodically applying ice packs on the patients. Passive rewarming started 26h after cardiac arrest and continued for 8±3h. Rebound hyperthermia (>38°C) occurred in eight patients 44h after cardiac arrest.

Conclusions
Intravenous cold saline infusion combined with ice packs is effective in inducing and maintaining therapeutic hypothermia, with good temperature control even during rewarming.

---
Resuscitation - 23 October 2009
(10.1016/j.resuscitation.2009.09.012)

【新知】Cardiocerebral Resuscitation

2009-10-24T09:42:00.000-07:00

Researchers at the University of Arizona created a new protocol for the management of OHCA that they termed "cardiocerebral resuscitation." CCR consists of 3 major parts: (1) continuous chest compressions with no early ventilations preshock and postshock; (2) delayed intubation; and (3) early use of epinephrine. A recent study that compared CCR with standard CPR in patients with shockable rhythms demonstrated that both survival (47.2% vs 19.6%) and percentage of survivors with good neurologic outcome (83.3% vs 77.8%) were significantly improved in those who underwent CCR.

http://www.medscape.com/viewarticle/707616

Summary

Ewy and Kern, both leaders in the field of cardiac resuscitation, reviewed CCR and described ideal postresuscitation care. The "3 pillars" of CCR were described:

A. Compression-only CPR by anyone who witnessed the event.
B. CCR by emergency medical service personnel, assumed to be arriving > 5 minutes postarrest.

200 chest compressions (at 100/minute), delay intubation; second person to apply defibrillation pads and initiate passive oxygen insufflation (eg, 100% oxygen via facemask)
Single shock if indicated, immediately followed by 200 more chest compressions (no pulse check after shock)
Check for pulse and rhythm; note that this pulse check occurs 4 minutes after the CCR has begun
EPI intravenously or intraosseously as soon as possible to improve central circulation, coronary circulation, and diastolic blood pressure
Repeat (2) and (3) 3 times; intubate if no return of spontaneous circulation after 3 cycles; note that neither bag-valve-mask ventilation nor intubation occurs until 12 minutes after the CCR has begun
Continue resuscitation efforts with minimal interruptions of chest compressions until resuscitation is successful or the person is pronounced dead

Viewpoint

In summary, the traditional mantra in emergency medicine of "A-B-C" has been turned upside-down by CCR. Aggressive management of the airway in those who have cardiac arrest is being relegated to a far lower priority. Good chest compressions and early EPI administration are the most important interventions when ventricular fibrillation is present in the circulation phase of cardiac arrest. Future studies will need to evaluate whether these concepts are applicable to nonshockable rhythms as well, although intuitively this seems reasonable. Finally, those who survive cardiac arrest should be treated with induced hypothermia, and pending more studies, they may benefit from early coronary angiography and PCI as well.

新版的「用力壓、快快壓」果然有效！

2009-10-23T20:21:00.000-07:00

Compress the Chest: Better CPR Improves Survival from Out-of-Hospital Cardiac Arrest
Implementation of the 2005 AHA CPR guidelines that focus on uninterrupted chest compressions nearly doubled the odds of survival among patients with out-of-hospital cardiac arrest.

In 2005, the American Heart Association (AHA) released updated evidence-based guidelines for cardiopulmonary resuscitation and emergency cardiovascular care, but does adherence to the revised protocol improve outcomes? Investigators compared rates of survival from out-of-hospital cardiac arrest among 606 adult patients treated before and 1021 treated after implementation of the 2005 AHA guidelines in a single large emergency medical services system.

Review of a convenience sample of 69 electronic electrocardiogram recordings showed significant improvement in CPR quality after guideline implementation, including improvements in mean chest-compression rate, proportion of time that patients received chest compressions, and median preshock and postshock pause times for compressions. Unadjusted rates of survival to hospital discharge were significantly higher after implementation of the guidelines than before (9.4% vs. 6.1%). Among patients with witnessed arrest whose initial rhythm was ventricular fibrillation on EMS arrival, survival rates improved significantly from 24% (19 of 78) before implementation to 30% (34 of 112) after. Multivariate regression analysis that adjusted for initial rhythm, sex, arrest location, and witnessed arrest showed 1.8 greater odds of survival in the postintervention period.

Comment: The promising results of this large study suggest the AHA was on the right track with its renewed focus on basic CPR, including the importance of providing uninterrupted chest compressions.

—
Kristi L. Koenig, MD, FACEP
Published in Journal Watch Emergency Medicine October 23, 2009

Citation(s): Sayre MR et al. Impact of the 2005 American Heart Association cardiopulmonary resuscitation and emergency cardiovascular care guidelines on out-of-hospital cardiac arrest survival. Prehosp Emerg Care 2009 Oct-Dec; 13:469.

AMI 之症狀表現：性別差異

2009-10-23T06:45:00.000-07:00

Symptoms of a first acute myocardial infarction in women and men

Background: Many studies have compared women and men for symptoms of acute myocardial infarction (AMI), but findings have been inconsistent, largely because of varying inclusion criteria, different study populations, and different methods.

Objective: The purpose of this study was to analyze gender differences in symptoms in a well-defined, population-based sample of women and men who experienced a first AMI.

Methods: Information on symptoms was collected from the medical charts of all patients with a first AMI, aged 25 to 74 years, who had taken part in the INTERGENE (Interplay Between Genetic Susceptibility and Environmental Factors for the Risk of Chronic Diseases) study. INTERGENE was a population-based research program on risk factors for cardiovascular disease. Medical charts were reviewed for each patient to determine the symptoms of AMI, and the prevalence of each symptom was compared according to sex.

Results: The study included 225 patients with a first AMI: 52 women and 173 men. Chest pain was the most common symptom, affecting 88.5% (46/52) of the women and 94.8% (164/173) of the men, with no statistically significant difference between the sexes. Women had significantly higher rates of 4 symptoms: nausea (53.8% [28/52] vs 29.5% [51/173]; age-adjusted odds ratio [OR] = 2.78; 95% CI, 1.47–5.25), back pain (42.3% [22/52] vs 14.5% [25/173]; OR = 4.29; 95% CI, 2.14–8.62), dizziness (17.3% [9/52] vs 7.5% [13/173]; OR = 2.60; 95% CI, 1.04–6.50), and palpitations (11.5% [6/52] vs 2.9% [5/173]; OR = 3.99; 95% CI, 1.15–13.84). No significant gender differences were found in the proportions of patients experiencing arm or shoulder pain, diaphoresis, dyspnea, fatigue, neck pain, abdominal pain, vomiting, jaw pain, or syncope/lightheadedness. No significant differences were found in the duration, type, or location of chest pain. The medical charts listed numerically more symptoms in women than in men; 73.1% (38/52) of the women but only 48.0% (83/173) of the men reported >3 symptoms (age-adjusted OR = 3.26; 95% CI, 1.62–6.54).

Conclusions: Chest pain is the most common presenting symptom in both women and men with AMI. Nausea, back pain, dizziness, and palpitations were significantly more common in women. Women as a group displayed a greater number of symptoms than did men.

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Gender Medicine. Volume 6, Issue 3, September 2009, Pages 454-462
http://dx.doi.org/10.1016/j.genm.2009.09.007

類固醇治偏頭痛無效

2009-10-23T06:40:00.000-07:00

Steroids for migraine headaches: a randomized double-blind, two-armed, placebo-controlled trial

Background:
Recurrence of migraine headache after treatment in the emergency department (ED) is common. Conflicting evidence exists regarding the utility of steroids in preventing migraine headache recurrence at 24–48 h.

Objective:
To determine if steroids decrease the headache recurrence in patients treated for migraine headaches in the ED.

Methods:
Double-blind placebo-controlled, two-tailed randomized trial. Patients aged >17 years with a moderately severe migraine headache diagnosed by treating Emergency Physician were approached for participation. Enrollees received either dexamethasone (10 mg i.v.) if intravenous access was utilized or prednisone (40 mg by mouth × 2 days) if no intravenous access was obtained. Each medication was matched with an identical-appearing placebo. Patients were contacted 24–72 h after the ED visit to assess headache recurrence.

Results:
A total of 181 patients were enrolled. Eight were lost to follow-up, 6 in the dexamethasone group and 2 in the prednisone arm. Participants had a mean age of 37 years (±10 years), with 86% female. Eighty-six percent met the International Headache Society Criteria for migraine headache. Of the 173 patients with completed follow-up, 20/91 (22%) (95% confidence interval [CI] 13.5–30.5) in the steroid arm and 26/82 (32%) (95% CI 21.9–42.1) in the placebo arm had recurrent headaches (p = 0.21).

Conclusion:
We did not find a statistically significant decrease in headache recurrence in patients treated with steroids for migraine headaches.

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http://www.jem-journal.com/article/PIIS0736467909007471/abstract

Management of Necrotizing Fasciitis

2009-10-22T05:41:00.000-07:00

There are four general principles that guide the management of a necrotizing soft-tissue infection: (1) early identification, (2) source control, (3) antibiotics, and (4) supportive care. Early identification of a serious necrotizing soft-tissue infection may not be straightforward. The typical signs are erythema, purplish discoloration of the skin with bullae, edema, crepitus, and pain that seems disproportionate to the findings on examination. Since in many cases, not all these signs are present, practitioners may underestimate the extent of the disease process. Surgical control of the source of the infection is a lifesaving maneuver. Because of this, emphasis is placed on removing affected tissue, regardless of possible resultant cosmetic defects. Removal of the necrotic tissue and the bacterial load allows antibiotics to control the spread of bacteria more effectively. Because of the rapidity with which necrotizing fasciitis spreads, time is of the essence when dealing with source control. Despite early aggressive surgical débridement, mortality rates range from 16 to 45%.

New England Journal of Medicine - Vol. 361, No. 17, October 22, 2009

急診筆記

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為何偏好洗血管不洗腹膜？

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氧氣沒有想像中有幫助

補充鈣補過頭小心會心肌梗塞！

Alteplase for stroke - up to 4.5 hr

最新版 ICH guidelines

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收縮壓維持在130左右最好

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單次掉血壓也可能是嚴重創傷的指標之一

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Vertigo 如何診治？

氧氣治療AMI...有害？！

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Statin 的副作用？

又一篇Plavix加PPI

TPA for stroke之4.5小時黃金時間

Infectious Mononucleosis

小朋友用ondanstron要注意什麼？

血糖控制太快也可能出問題...

AAA Repair

Lactate clearance 和 ScvO2 一樣好

聲音嘶啞(hoarseness)的注意事項

有5%的SAH是NE正常但已中線位移

【EBM】App 做 CT 不必打顯影劑

Vertebral osteomyelitis

EtCO2 已是 standard of care？

commotio cordis

18歲以下之OHCA：不能只做壓胸之CPR

休克治療：dopamine...可以被norepinephrine取代了！？

Gastroesophageal varices

以Lactate取代ScvO2

Scabies 之治療

何謂 scabies？

簡單步驟減少院內感染

原來肌肉放鬆藥物也可能只是味素藥...

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Jet Lag

穿刺傷病患到院前不宜浪費時間做脊椎固定術

CT Radiation Exposure and Cancer

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What is Takotsubo cardiomyopathy?

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孕婦H1N1流感重症的特徵