NEJM Volume 357:e30 December 27, 2007 Number 26
NEJM Volume 357:e30 December 27, 2007 Number 26
ICDs: Not a Cure for VT or VF
Patients with a history of myocardial infarction who survive a spontaneous episode of ventricular arrhythmia are at high risk for subsequent sudden death from recurrent ventricular tachycardia or ventricular fibrillation. Implantable cardioverter-defibrillators (ICDs) decrease mortality and have, therefore, become the mainstay of treatment. However, ICDs are not a cure for ventricular arrhythmias. Defibrillator discharges (shocks) for treatment of recurrent arrhythmias are painful, and syncope may occur before delivery of therapy.
Catheter-Based Mapping and Ablation Techniques
Catheter-based mapping and ablation techniques represent nonpharmacologic methods for the treatment of ventricular tachycardia. The most common indication for radiofrequency ablation is ventricular tachycardia refractory to drug therapy in patients with coronary artery disease that results in frequent shocks from an ICD. However, only 5 to 10% of patients with coronary artery disease show sufficient hemodynamic stability to allow identification of target sites with catheter-based mapping during an episode of ventricular tachycardia. This limitation thus sharply constrains the clinical application of catheter ablation.
Q: What is an 『ICD storm?』
A: An 『ICD storm』 is the term used to describe repeated ICD (implantable cardioverter-defibrillator) shocks delivered within a short time interval. These events occur in 10 to 25% of patients with implantable cardioverter-defibrillators. Clinically significant anxiety and depression as a result of recurrent ICD shocks may occur in more than 50% of patients.
3.其它 : 像是高壓氧治療、星狀神經節阻斷術等。高壓氧是一個具有潛在效益的另類輔助治療。
By 台中榮總急診室護士 - 張惠風
危險因子主要包括高血壓、外因性血管傷害、使用cocaine、孕婦及先天性疾病( 如Marfan syndrome )等。如果病患高血壓沒有控制得宜，往往是造成主動脈剝離的最大原因。
在臨床上Stanford （史丹福）分類以有無侵犯升主動脈作為分類之依據，如侵犯到升主動脈為Stanford （史丹福） A 型，其餘皆稱作 B 型。手術對A 型的主動脈剝離可以降低一半之死亡率，也被推薦為標準的治療方法。以長期預後而言，手術仍比藥物治療有較長的存活率。Stanford （史丹福）B 型的急性主動脈剝離是以藥物為主要治療方法，主要原則是控制血壓。
By 台中榮總急診部總醫師 - 黃植謙
Normal Saline = 0.9% NaCl. 1 L 之 Normal Saline 含154 mEq/L of Na+ and154 mEq/L of Cl-
1 L 之 Lactated Ringer's Solution 含:130 mEq/L of Na+109 mEq/L of Cl-28 mEq/L of lactate4 mEq/L of potassium3 mEq/L of calcium
Lactate converts to bicarbonate in liver. Patients with lactic acidosis usually have inadequate liver metabolism of lactate so conversion to HCO3- from the infused lactate of LR is impaired and may give false readings of serial lactate measurements but may be a better choice in regular situations where hyperchloremia restricts use of normal saline.
Procedure: Central Venous Catheterization
The placement of a central venous catheter is indicated for the continuous monitoring of central venous pressure and for the delivery of critical or caustic medications.
Complications of Central Line Placement
Specific complications associated temporarily with placement of a subclavian line include hemothorax and pneumothorax, air embolism, inadvertent arterial puncture, and aortic perforation. Obtain a chest radiograph after placement to assess for complications and to confirm correct placement of the catheter. Common malplacement locations include placement transverse to the contralateral subclavian vein, retrograde into the ipsilateral internal jugular vein, or potentially the contralateral internal jugular vein.
Guidelines to Decrease Risk of Infection
The Institute for Healthcare Improvement has developed specific guidelines to help decrease the risk of infection in patients with central venous catheters. The guidelines include the use of proper hand hygiene, the use of maximal barrier precautions during placement, the use of chlorhexidine skin antisepsis, and daily review of the need for the catheter.
Morning Report Questions
Q: In what position should a patient be placed in for insertion of a central line in the subclavian vein? Does the use of a rolled towel under the spine increase or decrease the size of the subclavian vein?
A: A patient who is undergoing placement of a central line in the subclavian vein should be placed in a 15-degree Trendelenburg position. If you place a rolled towel or similar object under the spine to help identify the patient's external landmarks, be aware that propping the shoulder or turning the head has been shown to decrease the size of the vein on ultrasonography.
Q: What are general contraindications for placement of a central venous catheter?
A: General contraindications for placement of a central venous catheter include infection of the area overlying the target vein and thrombosis of the target vein. Specific contraindications to the subclavian approach include fracture of the ipsilateral clavicle or anterior proximal ribs, which can distort the anatomy and make placement difficult. Greater caution should be used when placing a central venous catheter in coagulopathic patients. The location of the artery (beneath the clavicle) makes application of direct pressure nearly impossible in attempts to control bleeding.
這裡有 teaching video 可以下載：
Morning Report Question
NEJM Clinical Pearls
Dengue fever and yellow fever are important human viral diseases caused by single-stranded RNA viruses transmitted by insects. Although nearly half the world's population is at risk for infection of dengue fever, and as many as 100 million cases of infection occur annually, there are no antiviral drugs to treat dengue fever and no vaccines to prevent it. Conversely, yellow fever is now largely controlled by vaccination, but many regions are susceptible to a reemergence if the disease is introduced by travelers, and substantial, recent problems with vaccine safety may change vaccination policy.
Dengue Fever and Dengue Hemorrhagic Fever
In its classic form, dengue is an acute illness, characterized by fever, headache, muscle and joint pain, and rash. Immunity against a specific serotype is lifelong, but previous infection with one serotype is a risk factor for a more severe form of dengue — dengue hemorrhagic fever — upon subsequent infection with another serotype. Dengue hemorrhagic fever is characterized by the capillary-leak syndrome, thrombocytopenia, hemorrhage, hypotension, and shock. Approximately 500,000 cases of dengue hemorrhagic fever occur annually, with a case fatality rate ranging from 1 to 3% to as high as 10 to 20%, depending on the available fluid management and intensive care.
Dengue and Yellow Fever Mosquitoes
Dengue and yellow fever are endemic to and epidemic in tropical regions with the principal vector being Aedes aegypti mosquitoes. Infected humans have high blood levels of virus and can therefore infect vector mosquitoes. After an incubation period of about 10 days, during which the virus replicates in a person's salivary-gland tissues, blood-feeding aedes mosquitoes can become infected and transmit the virus to another person. A. aegypti mosquitoes are prevalent in the southern United States, which is therefore receptive to the introduction and spread of both dengue and yellow fever.
Q: What recent problems have occurred with the yellow fever vaccine?
A: Viscerotropic disease, a new syndrome, has been associated with the yellow fever vaccine, an extensive infection of vital organs by a 17D virus that is indistinguishable from wild-type yellow fever disease and has a 60% case fatality rate. Genetic factors of the host (possibly in genes involved in interferon responses) and acquired factors (advanced age and thymectomy) appear to underlie susceptibility to this condition. The overall incidence is about 1 case for every 200,000 to 400,000 vaccinations, but among persons over 60 years of age, the incidence is as high as 1 for every 50,000 vaccinations — which makes 17D one of the least safe vaccines in use.
Abdominal CT versus X-Ray
Organ doses of radiation from CT scanning are considerably larger than those from corresponding conventional radiography. A conventional anterior-posterior abdominal x-ray examination results in a dose to the stomach of approximately 0.25 mGy, which is at least 50 times smaller than the corresponding stomach dose from an abdominal CT scan. A posterior-anterior chest x-ray would result in a radiation dose to the lungs of 0.01 mGy and a lateral chest x-ray, of a radiation dose of 0.15 mGy to the lungs.
Morning Report Questions
Q: Why are more children undergoing diagnostic testing with CT scanning?
A: The major growth area in CT use for children has been for the presurgical diagnosis of appendicitis, for which CT appears to be both accurate and cost-effective — though usually no more so than ultrasonography. A considerable literature questions the use of CT, particularly as a primary diagnostic tool for acute appendicitis in children. A poll of pediatric radiologists (Slovis, Pediatr Radiol, 2002) suggested that perhaps one third of all CT studies could be replaced by alternative approaches or not performed at all.
Q: What is a gray (Gy) — the unit used to describe the radiation dose delivered by a CT scan?
A: Various measures are used to describe the radiation delivered by CT scanning, the most relevant being absorbed dose, effective dose, and CT dose index. The absorbed dose is the energy absorbed per unit of mass and is measured in grays (Gy). One gray equals 1 joule of radiation energy absorbed per kilogram.
Morning Report Questions
Q: What is Loffler's endocarditis?
A: Loffler's endocarditis is a restrictive cardiomyopathy due to endomyocardial disease with mural thrombi (so-called thrombotic endocarditis) and is secondary to eosinophilia from many causes. Peripheral eosinophilia is almost always present in Loffler's endocarditis, usually present in acute necrotizing eosinophilic myocarditis, sometimes present in hypersensitivity myocarditis, and rarely present in endomyocardial fibrosis (a restrictive cardiomyopathy affecting persons in tropical climates).
Q: What is a known side effect of the medication modafinil used for treatment of fatigue in patients with multiple sclerosis?
A: Modafinil can cause multiorgan hypersensitivity reactions. The Food and Drug Administration now requires a package insert for modafinil that includes this warning. Drugs that have been associated specifically with hypersensitivity myocarditis include antibiotics (sulfonamides, beta-lactams, tetracyclines, aminoglycosides, and others), cardiac medications (methyldopa, dobutamine, thiazides, and furosemide), antiepileptics (phenytoin, carbamazepine), psychotropics, antimycobacterials (streptomycin), and nonsteroidal antiinflammatory drugs.
Acute Eosinophilic Myocarditis
Acute eosinophilic myocarditis (also known as hypersensitivity myocarditis) is caused by a drug hypersensitivity reaction and is characterized by fever, rash, peripheral eosinophilia, and elevated biomarkers of necrosis. ECG occasionally shows ST-segment elevation. Echocardiography reveals mild systolic dysfunction, increased wall thickness due to edema, and occasionally a pericardial effusion. Heart failure is typically mild, and patients die of arrhythmias, rather than pump dysfunction.
Autoimmune Myocarditis and Viral Myocarditis
Autoimmune myocarditis can occur in patients with autoimmune disorders such as systemic lupus erythematosus and polymyositis. Both can cause pericarditis and myocarditis, but the myocarditis tends to be mild. Viral myocarditis is often preceded by a viral syndrome, although this finding is neither sensitive nor specific. Presentations range from slow development of heart failure to rapid development of cardiogenic shock. The ECG often shows nonspecific ST-segment and T-wave abnormalities; echocardiographic findings range from a nondilated left ventricle seen in the acute phase to a spherical, dilated left ventricle in the chronic phase.
Diverticulosis: Low Fiber, Constipation, and NSAIDs
The cause of colonic diverticular disease has not yet been conclusively established. Epidemiologic studies have demonstrated associations between diverticulosis and diets that are low in dietary fiber and high in refined carbohydrates. Other factors that have been associated with an increased risk of diverticular disease include physical inactivity, constipation, obesity, smoking, and treatment with nonsteroidal antiinflammatory drugs.
The clinical manifestations of acute colonic diverticulitis vary with the extent of the disease process. In classic cases, patients report obstipation and abdominal pain that localizes to the left lower quadrant. An abdominal fullness or perirectal fullness, or “mass effect,” may be apparent. Stool guaiac testing may be trace-positive. A low-grade fever is common, as is leukocytosis. Computed tomography (CT) is recommended as the initial radiologic examination.
Morning Report Questions
Q: What is the recommended treatment for a patient suspected of suffering from acute diverticulitis?
A: The decision to hospitalize a patient for diverticulitis depends on the patient's clinical status. For most patients (i.e., immunocompetent patients who have a mild attack and can tolerate oral intake), outpatient therapy is reasonable. This involves 7 to 10 days of oral broad-spectrum antimicrobial therapy, including coverage against anaerobic microorganisms. A combination of ciprofloxacin and metronidazole is often used, but many other combinations are effective. Hospitalization is indicated if the patient is unable to tolerate oral intake or has pain severe enough to require narcotic analgesia or if symptoms fail to improve despite adequate outpatient therapy. Hospitalized patients are usually made NPO (nothing by mouth) and may be candidates for possible nasogastric tube placement if there is evidence of obstruction or ileus.
Q: Is colonoscopy or sigmoidoscopy recommended during an acute diverticulitis attack?
A: Colonoscopy and sigmoidoscopy are typically avoided when acute diverticulitis is suspected because of the risk of perforation or other exacerbation of the disease process. Expert opinion favors performing these tests when the acute process has resolved, usually after approximately 6 weeks, to rule out the presence of other diseases, such as cancer and inflammatory bowel disease.
The FDA has approved additional boxed warnings and label updates for the erythropoiesis-stimulating agents Aranesp, Epogen, and Procrit.
The new warnings note that when the drugs were dosed to achieve hemoglobin levels over 12 g/dL, they stimulated tumor growth and decreased survival in patients with advanced breast, head and neck, lymphoid, and non-small cell lung cancer. (Higher mortality and tumor progression have not been ruled out at levels under 12 g/dL.)
When used to maintain hemoglobin levels over 12 g/dL in patients with chronic renal failure, the drugs increased the risk for death, stroke, heart attack, and heart failure. In these patients, the FDA recommends aiming for hemoglobin levels between 10 and 12 g/dL.
Common Organisms in Bacterial Meningitis
The most common bacteria causing meningitis in adults are Streptococcus pneumoniae (about half of cases), Neisseria meningitidis (about one fifth of cases), Listeria monocytogenes (about one tenth of cases), and Haemophilus influenzae (about one tenth of cases). The otitic meningitis in this patient (whose ear infection may have caused bony erosion that led to a cerebrospinal fluid fistula) prompted the clinicians to consider more aggressive organisms such as Staphylococcus aureus, gram-negative organisms, and group A streptococcus. In fact, blood and cerebrospinal cultures became positive for group A streptococcus within a few hours.
Group A Streptococcus Meningitis
Infections with group A streptococcus are a rare cause of bacterial meningitis, accounting for 0.5 to 1.5% of community-acquired cases; the mortality rate (27%) is similar to that for pneumococcal meningitis (30%). Otitis media due to group A streptococcus is associated with high rates of local invasion, including tympanic perforation and mastoiditis, and this form of otitis media is the most important risk factor for group streptococcal meningitis among adult patients. Most patients with group A streptococcal meningitis do not have the clinical features of septic shock associated with invasive streptococcal disease, and the incidence of group A streptococcal meningitis has not increased, despite an increasing incidence of other forms of invasive disease.
Morning Report Question
Q: An important clinical challenge is how to recognize when fluid emanating from the ear or the nose is, in fact, cerebrospinal fluid. How might this be accomplished?
A: Otorrhea and rhinorrhea may be recognized as containing cerebrospinal fluid if the fluid has a relatively low protein level (less than 2 g/L) and should be clinically suspected when a handkerchief or cloth soaked in the fluid does not stiffen when dry. A fluid glucose level of greater than 40 mg per deciliter (2.2 mmol per liter) also suggests that the fluid is cerebrospinal fluid. The most accurate test is a measurement of β2-transferrin, a protein that is found only in cerebrospinal fluid. Of note, cerebrospinal fluid otorrhea may be serosanguineous and mistaken for blood.
Patrick's test stresses the hip and sacroiliac joints. A positive test produces back, buttocks, or groin pain. The thigh and knee of the supine patient are flexed, and the external malleolus of the ankle is placed over the patella of the opposite leg. The test is positive if depression of the knee produces pain.
- The Patrick or FABER test is a screening test for pathology of the hip joint or sacrum.
- The test is performed as follows: Place the patient in the supine position. Flex the leg and put the foot of the tested leg on the opposite knee (the motion is that of Flexion, ABduction, External Rotation at the hip). Slowly press down on the superior aspect of the tested knee joint lowering the leg into further abduction
- The test is positive if there is pain at the hip or sacral joint, or if the leg can not lower to the point of being parallel to the opposite leg.
The chest radiograph demonstrates an enlarged collateral intercostal arterial circulation that has caused notching of the inferior-posterior rib margins, which is supportive of the diagnosis.
EDs and ICUs should work together to implement this treatment for patients with severe sepsis and septic shock.
Although early goal-directed therapy (EGDT) has been shown to improve outcomes in severe sepsis and septic shock, clinical implementation has been slow. Barriers such as cost, emergency department overcrowding, lack of training, and institutional resistance present significant challenges to use of EGDT. To assess the economic consequences of implementing EGDT, researchers conducted a decision analysis of three implementation strategies: ED-centric (all treatment administered in the ED), mobile intensive care unit (ICU) team (ED screens patients and then alerts the ICU team, which provides EGDT), and ICU-centric (EGDT administered in the ICU after ED transfer).
Estimates were derived using data from multiple sources, including the Henry Ford Health System, Medicare, the U.S. Public Health Service, and the American Thoracic Society. Analyses were based on assumptions that an average ED has an annual volume of 29,100 visits and 91 cases of severe sepsis and septic shock. The authors estimated that start-up costs would range from US$13,000 (ICU-centric) to $30,000 (ED-centric) and that additional annual costs would be $100,000.
Compared with usual care, EGDT saved an estimated mean of $8,666 per patient, representing a 22.9% reduction in hospital costs per patient and a yearly savings of nearly $800,000 per hospital. The savings were due primarily to a reduction in length of ICU stay. Although the ICU-centric model was the least costly, it was also the least effective because of time delays. In sensitivity analysis, EGDT remained cost-effective in all three models even when the mortality benefit was reduced by almost half. Cost per quality-adjusted life-year was $7,019 in the ED-centric model, $6,931 in the ICU-team model, and $2,749 in the ICU-centric model.
EGDT can save lives and money — even according to a conservative model that was created with bias against EGDTs cost-effectiveness by assigning substantial start-up costs. In addition, EGDT remained cost-effective in sensitivity analysis that was further biased against it by substantially reducing the mortality benefit. Although EDs have the infrastructure to manage critically ill cases, the authors included in their analyses costs not only for increased staffing, training, and screening but also for upgrading two additional rooms for invasive monitoring. EDs and ICUs should work together to implement EGDT, as it benefits both hospitals and patients.
— Tiffany M. Osborn, MD
Published in Journal Watch Emergency Medicine November 2, 2007
Citation(s):Huang DT et al. Implementation of early goal-directed therapy for severe sepsis and septic shock: A decision analysis. Crit Care Med 2007 Sep; 35:2090.
Q: In a patient who sustains a hip fracture, what is the risk for subsequent fracture and/or death?
A: Persons who fracture a hip are 2.5 times as likely to have a subsequent skeletal fracture as are those without a hip fracture. In patients who have sustained a hip fracture, there is an increase in mortality; a 2-year mortality rate of 36% has been observed. Mortality in the year after hip fracture has been reported to cause an estimated 9 excess deaths per 100 patients among women 70 years and older. Many of those who survive do not regain their prefracture level of mobility and thereby endure loss of independence and deterioration in health-related quality of life.
Q: What types of treatment (drug and non-drug) are currently used to prevent hip fractures?
A: Treatment to prevent hip fractures includes bisphosphonates (oral and intravenous), vitamin D and calcium supplementation, nasal calcitonin, selective estrogen-receptor modulators, hormone replacement, tibolone (a synthetic steroid), and padded hip protectors. Home safety (removal of risks in the home such as loose rugs) strength-training and balance/coordination exercises have also been recommended.
Acute Symmetric Polyarthritis
The differential diagnosis for systemic inflammatory arthritis includes autoimmune inflammatory arthritis (such as rheumatoid arthritis, psoriatic arthritis, and systemic lupus erythematous), microcrystalline arthritis (including gout or pseudogout), and infectious or postinfectious arthritis (including acute rheumatic fever from group A streptococcus, reactive arthritis from bowel or genitourinary infection, or Lyme disease).
Viruses that Can Cause Arthritis
Parvovirus B19 infection can present with acute arthritis; this occurs more often in adults than in children. The most common clinical presentation of Parvovirus B19 in childhood is erythema infectiosum or fifth disease, (“slapped cheek” appearance and a reticular rash on the torso and limbs). In contrast, adults with parvovirus B19 infection often present with a more debilitating, influenza-like illness; and as many as 60% of adults with infection present with clinically important arthralgias or arthritis. Adenovirus, coxsackievirus, Epstein–Barr virus, cytomegalovirus, rubella, mumps, and retroviruses can also cause arthralgias or acute arthritis.
Q: Does a negative rheumatoid factor rule out rheumatoid arthritis?
A: Rheumatoid-factor seronegativity does not rule out rheumatoid arthritis, but it does reduce the likelihood that a patient has the disease. However, it is of note that the occasional presence of autoantibodies, including rheumatoid factor antibodies, may be found in the presence of viral infections, albeit at a low titer, without the presence of rheumatoid arthritis.
Q: Intrauterine infection with parvovirus B19 can cause what serious outcome?
A: Intrauterine infection with parvovirus B19 is a major cause of hydrops fetalis. The estimated risk of fetal infection when a woman is infected with parvovirus during pregnancy is 30% with a 5 to 9% risk of fetal loss. Infection during the second trimester appears to pose the greatest risk of hydrops fetalis.
Q：什麼是propofol infusion syndrome
A: Propofol infusion syndrome是指高劑量給予propofol之後造成心臟衰竭、代謝性中毒、橫紋肌溶解、高脂血症及高血鉀等症狀。早在1992年，Parke等人發表病例報告指出，5位重症加護照顧的上呼吸道感染嬰幼兒，發生代謝性酸中毒及致死性心臟衰竭可能與使用propofol鎮靜劑有關。1998年Bray的回溯性研究，納入主要診斷為呼吸道感染，於加護病房治療超過48小時的12歲以下兒童。並且定義propofol infusion syndrome為突然心跳過慢，治療無效，導致心臟收縮不全且合併1.高脂血症2.代謝性酸中毒3.橫紋肌溶解4.屍體解剖肝腫大，脂肪浸潤等4項症狀其中1項。結果顯示使用propofol劑量大於4 mg/kg/hr，輸注期間大於48小時，死亡的危險性可達26.3 %，遠比使用其他藥物如benzodiazepine及opioids高。
Q: propofol infusion syndrome與頭部受傷病患之相關性
A: 頭部受傷病患可能為propofol infusion syndrome的高危險群。propofol經常使用於頭部受傷患者手術時之麻醉、鎮靜、降低顱內壓或控制重積性癲癇。Cremer等人服務的神經外科加護病房發現有5位成人病患，頭部受傷入院後的第4或第5天死於無法解釋的心臟衰竭，症狀與兒科加護病房之報告相似。於是Cremer等人回顧該院1996-1999年間，神經外科加護病房，16-55歲的頭部受傷病患。納入分析的病患為使用呼吸器及鎮靜劑propofol超過48小時。其中也包括使用較大劑量propofol以降低顱內壓及腦代謝（一般調整propofol劑量以維持顱內壓小於20 mmHg，腦灌流壓大於70 mmHg）。結果於合乎條件的67位病患中有7位發生propofol infusion syndrome。這7位病患注射propofol劑量平均為6.5 mg/kg/hr，使用期間超過58小時。並且於開始注射propofol之後都必須同時併用血管加壓劑來維持生命徵象。而未發生propofol infusion syndrome的60位病患注射propofol劑量平均為4.8 mg/kg/hr。經過分析結果發現，使用propofol輸注劑量小於5 mg/kg/hr的病患皆未發生propofol infusion syndrome。而使用propofol輸注劑量大於5 mg/kg/hr的病患有17 %發生此症狀，至於propofol輸注劑量大於6 mg/kg/hr的病患則有高達31 %發生此症狀。
雖然propofol使用於重症病患之鎮靜劑量通常為0.3-4 mg/kg/hr，但對於頭部損傷之病患，為了降低顱內壓、腦代謝以保護顱腦避免二度傷害，可能需要使用較高的劑量達4-12 mg/kg/hr。然而使用propofol常見的副作用為低血壓，此時臨床上為了維持propofol的持續效用，又要兼顧血壓的維持，才可以達到足夠的腦灌流壓大於70 mmHg，這樣的做法可能會惡化心臟衰竭及代謝性中毒等情形。更甚的是，使用血管加壓劑會降低臟器血流，結果導致propofol濃度升高。如此一來便會增加此致命的propofol infusion syndrome之可能性。所以在加護病房對重症病患的人性化照顧中，一方面要讓病患減輕焦慮，增加舒適性；一方面達到治療控制病情效果的同時，「propofol infusion syndrome」這種致命性的問題不可小覤。
因此建議加護病房使用propofol輸注時，成人劑量應該控制於小於5 mg/kg/hr。尤其是頭部受傷病患更應該注意避免引發propofol infusion syndrome。
PCI versus Medical Management for Stable Angina
The results of the recent Clinical outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial raises questions about using PCI over optimal medical therapy regarding the composite end point of death or myocardial infarction. However, angina symptoms were significantly reduced with the use of PCI, a phenomenon that has been reported in multiple clinical trials. However, there is no evidence that PCI in patients with stable angina is more effective than optimal medical management in reducing mortality.
PCI versus CABG
The addition of CABG to medical therapy in recent randomized trials does appear to extend the survival of patients with advanced, multifocal coronary artery disease, such as three-vessel disease. If a patient has two-vessel coronary artery disease, without involvement of the proximal left anterior descending coronary artery, then PCI may be preferable as compared to CABG. If a drug-eluting stent is placed during PCI to reduce the risks of restenosis and repeat revascularization, then the patient will need dual antiplatelet therapy (aspirin plus clopidogrel) for at least 1 year and perhaps indefinitely.
Morning Report Question
Q: What is a contraindication to the use of metformin?
A: Safe use of metformin requires normal renal function. In fact, any degree of renal insufficiency is a contraindication for metformin use. Metformin is not recommended if the creatinine is >1.5 mg per deciliter in a man or >1.4 mg per deciliter in a woman.
- Red to blue: about 1 to 2 days old
- Blue to purple: about 3 to 5 days old
- Green: about 6 to 7 days old
- Yellow to brown: about 8 to 10 days old
- Resolved: at least 13 to 28 days old
- It is likely safest to describe bruises as either "new" (red, purple, or blue) or "old" (green, yellow, or brown)
Note: The presence of bruises that have various ages may signify multiple episodes of injury caused by ongoing physical abuse.
Many hospitals removed droperidol from the emergency department formulary after the U.S. FDA issued a black box warning in 2001. Haloperidol, another butyrophenone, is also commonly used, both intramuscularly and intravenously, to control agitated patients in the ED. In September 2007, the FDA released a warning that torsades de pointes and QT prolongation might occur in patients receiving haloperidol, particularly when the drug is administered intravenously or at doses higher than recommended. The FDA notes that haloperidol is not approved for intravenous use.
The warning is based on a total of 242 case reports of QT prolongation or torsades de pointes, many of which were confounded by other agents or medical conditions that might cause these rhythm disturbances; several deaths occurred. The FDA states that, based on these reports alone, it cannot estimate the frequency of dysrhythmic events in patients receiving the drug.
Sedation often is a crucial part of medical care for agitated patients. Both haloperidol and droperidol are very effective agents, and these warnings do not preclude their use. However, it is prudent to document the need for these agents and to exercise caution when using them in patients who have other conditions that put them at risk for QT prolongation, such as hypokalemia, hypomagnesemia, hypothyroidism, long QT syndrome, cardiac abnormalities, and use of drugs known to prolong the QT interval. In cases in which emergent sedation is needed for the safety of the patient and the healthcare providers, these agents are usually the best option.
— Diane M. Birnbaumer, MD, FACEP
Published in Journal Watch Emergency Medicine October 12, 2007
U.S. Food and Drug Administration (FDA). Information for healthcare professionals: Haloperidol (marketed as Haldol, Haldol Decanoate and Haldol Lactate). 2007 Sep 17 . (http://www.fda.gov/Cder/drug/InfoSheets/HCP/haloperidol.htm)
Chest-Tube Insertion: Anatomical Location
Position the patient in either a supine or a semirecumbent position. Maximally abduct the ipsilateral arm or place it behind the patient's head. The area for insertion is approximated by the fourth to sixth intercostals space in the anterior axillary line at the horizontal level of the nipple. This area corresponds to the anterior border of the latissimus dorsi, the lateral border of the pectoralis major muscle, the apex just below the axilla, and a line above the horizontal level of the nipple — often referred to as the “triangle of safety.” You can isolate this area by palpating the ipsilateral clavicle, then working downward along the ribcage, counting down the rib spaces. Once the fourth to sixth intercostals space is felt, move your hand laterally toward the anterior axillary line. This is the area for incision; the actual insertion site should be one intercostals space above the chest-tube insertion.
The most important complications associated with chest-tube insertion include bleeding and hemothorax due to intercostal artery perforation, perforation of visceral organs (lung, heart, diaphragm, or intraabdominal organs), perforation of major vascular structures as the aorta or subclavian vessels, subcutaneous emphysema, reexpansion pulmonary edema, infection of the drainage site, pneumonia, empyema, and intercostal neuralgia. There may be technical problems such as intermittent tube blockage from clotted blood, pus, or debris, or incorrect positioning of the tube, which causes ineffective drainage.
What is the major concern when removing a chest tube?
The major concern with removal of a chest tube is the risk of pneumothorax during removal. Physician practice differs with respect to the point in the respiratory cycle at which the tube is removed: during end-inspiration or end-expiration. Neither has been shown to be superior in the prevention of pneumothorax. When preparing to remove the tube, two people may need to participate so that one can instruct the spontaneously breathing patient and pull the tube while the other can quickly occlude the insertion site.
What factors dictate what size chest tube to insert in a patient?
The size of the chest tube that is needed depends on the indication for the insertion of a chest tube. For a large pneumothorax in a patient in stable condition, a 16- to 22-French chest tube should be used with the open technique (a 14-French or smaller for Seldinger method). For a large pneumothorax in an unstable patient or a patient receiving mechanical ventilation, a 24- to 28-French chest tube catheter should be used. A smaller chest tube, 8- to 16-French can be used for a malignant or transudative pleural effusion.
From: N Engl J Med 357;15 http://www.nejm.org/ october 11, 2007.
圖片如下 (catheter 是白色的，機器上的 80 就是 ScvO2 = 80%).
如果有適合的 septic shock 個案，請多利用。
Positioning of the tip too close to the carina results in endobronchial intubation when the neck is flexed.
Endotracheal tubes ideally are placed with the tip near the midtrachea, thereby minimizing the likelihood that either endobronchial intubation or accidental extubation will occur when the patient's neck is flexed or extended. In pediatric patients, tube positioning is challenging because of variations in the length of both the tube and the trachea. Investigators in Korea randomized 107 children (aged 2–8 years) who were undergoing general anesthesia to one of three methods for initially positioning the tube at the correct depth.
In group I, the tube was inserted deliberately into a mainstem bronchus and then withdrawn 2 cm (in children aged 2–5 years) or 3 cm (in children older than 5) farther than the point at which bilateral breath sounds were heard. In group II, the tube was placed with the recommended centimeter marking aligned with the vocal cords ( i.e., the 4-cm mark for tubes with an internal diameter of 4 or 4.5 cm and the 5-cm mark for tubes with a diameter 5 cm). In group III, the tube was manipulated until its tip could be palpated in the suprasternal notch (anatomically near the midtrachea). The position of the tip relative to the carina and vocal cords was then measured using a fiber-optic bronchoscope, with the neck in neutral position, full flexion, and full extension.
In groups II and III, the tip of the tube initially was placed near the midtrachea (at positions 46.5% and 43.4%, respectively, of the distance from the carina to the vocal cords), whereas in group I, the tube was placed significantly closer to the carina ( 21.4% of the distance). Flexion brought the tube very close to the carina (9.5% of the distance) in group I, but not in groups II and III (38.3 and 32.4% of the distance, respectively). Extension brought the tube tip near the midtrachea in group I ( 44.3% of the distance) and into the upper third for groups II and III (71.7% and 67.9% of the distance, respectively). Flexion produced endobronchial intubation in 5 of 35 patients in group I (most aged 2 to 5 years), but not in any patients in the other groups. No patient was extubated by extension.
Comment: This study strongly affirms the importance of placing endotracheal tubes in children in the midtrachea, where neither endobronchial intubation nor accidental extubation will occur through the entire range of motion of the neck. The often- recommended method that was used for group I is clearly inferior for correct placement and should not be used.
— Ron M. Walls, MD, FRCPC, FACEP, FAAEM
Published in Journal Watch Emergency Medicine October 5, 2007
Citation(s): Yoo S-Y et al. A comparative study of endotracheal tube positioning methods in children: Safety from neck movement. Anesth Analg 2007 Sep; 105:620.
A 73-year-old man presented to the emergency department with a 4-day history of nonproductive cough that worsened at night. He did not have fever, chills, headache, myalgias, rhinorrhea, nasal congestion, sore throat, hemoptysis, chest pain, or dyspnea. What is the differential diagnosis?
Cough: Differential Diagnosis
The most common causes of acute cough (lasting <3>8 weeks) is most often attributable to gastroesophageal reflux disease, asthma, the upper-airway cough syndrome (formerly called postnasal drip), cigarette smoking, or use of ACE inhibitors. Other causes of cough include congestive heart failure, irritation of the bronchial airway by a foreign body, and cancer.
Pertussis in Adults
An important, but often overlooked, cause of cough in adults is infection with B. pertussis. Pertussis is often considered a childhood infection; however, several recent studies have shown that it is the cause of 12 to 32% of cases of prolonged cough (lasting >2 to 3 weeks) in adolescents and adults. Childhood vaccination against B. pertussis does not confer lifelong immunity. Immunity wanes after 5 to 10 years and rarely lasts more than 12 years.
Q : If you suspect pertussis infection in an adult patient, what tests should you perform to confirm the diagnosis?
A: Current recommendations for laboratory testing for pertussis include posterior nasopharyngeal culture or the PCR assay to be used as confirmatory tests for diagnosis. Since B. pertussis preferentially resides in ciliated respiratory epithelium, clinicians must obtain specimens from the posterior nasopharynx, not the anterior nares or throat. The sensitivity of the culture will be reduced by delayed transport to the laboratory and delayed plating of the specimen, as well as previous vaccination, recent antibiotic use, and prolonged illness.
Q: What antibiotic regimens are recommended for the treatment of pertussis? Should you start the antibiotics before the tests results return?
A: Since the results of microbiologic pertussis testing may not be available for a week or more, and because pertussis is highly contagious, antimicrobial treatment should be initiated when testing is ordered. Macrolide therapy is recommended for both treatment and postexposure prophylaxis: for adults, 500 mg of erythromycin four times daily for 14 days; 500 mg of azithromycin on day 1, followed by 250 mg daily on days 2 through 5; or 500 mg of clarithromycin twice daily for 7 days. Antimicrobial treatment initiated after 1 to 2 weeks of symptoms has little effect on the duration of the cough. When pertussis has lasted more than 7 days, antimicrobial therapy has little symptomatic benefit, but it reduces the risk of transmission. Postexposure prophylaxis should be offered to close contacts of patients with laboratory-confirmed cases, regardless of their age or vaccination status.
- Rady MY, Smithline HA, et al. A comparison of the shock index and conventional vital signs to identify acute, critical illness in the Emergency Department. Ann Emerg Med. 1994; 24: 685-690.
- Yealy DM, Delbridge TR. The shock index: All that glitters. Ann Emerg Med. 1994; 24: 714-715.
The patient is assigned a grade according to the best view obtained.
View obtained during Mallampati test:
1. Faucial pillars, soft palate and uvula visualised
2. Faucial pillars and soft palate visualised, but uvula masked by the base of the tongue
3. Only soft palate visualised
4. Soft palate not seen.
Clinically, Grade 1 usually predicts an easy intubation and Grade 3 or 4 suggests a significant chance that the patient will prove difficult to intubate.
The results from this test are influenced by the ability to open the mouth, the size and mobility of the tongue and other intra-oral structures and movement at the craniocervical junction.
- A simple method for obtaining temporary pelvic stabilization when an external fixator cannot be applied is the application of a circumferential pelvic anti-shock sheet (CPAS).
- Advantages of this technique include the fact that it is inexpensive and readily available in all EDs. Special training is not required and the emergency physician can apply the sheet. Lower extremity and abdominal access is maintained after the sheet is placed.
- Caution is required in patients with lateral compression pelvic ring injuries or sacral neuroforaminal fractures. Forceful or aggressive CPAS application could worsen visceral injury or sacral nerve root injury in these instances.
- Phenobarbital or barbiturate overdose
- All Class I antidysrhythmic overdose
- Other sodium channel blockers
- Tricyclic Antidepressant (TCA) Overdose
- Antihistamine Overdose
- Cocaine Overdose
- Chlorpropamide (Diabenese)
- Sulfonamides (some)
BACKGROUND: MRI is believed to be more sensitive than CT scanning for imaging ischemic stroke, but is considered insufficiently sensitive for acute hemorrhagic stroke.
METHODS: In this single-center study at a suburban hospital in Bethesda, MD, and coordinated at the National Institutes of Health, 356 patients with suspected acute strokes underwent MRI and CT scanning of the brain. The imaging studies were later reviewed by a panel of two neuroradiologists and two stroke neurologists blinded to the patients' clinical findings.
RESULTS: The final diagnosis was acute ischemic stroke in 190 patients (53%), acute intracranial hemorrhage in 27 (8%) and transient ischemic attack in 14 percent. Twenty-five percent of the patients were not ultimately diagnosed with cerebrovascular disease. The sensitivity of CT scanning was 26% for acute stroke overall, 16% for acute ischemic stroke and 89% for acute intracranial hemorrhage (corresponding specificities 98%, 98% and 100%, respectively). The sensitivity of MRI was 83% for acute stroke overall, 83% for acute ischemic stroke and 81% for acute intracranial hemorrhage (corresponding specificities, 97%, 96% and 100%, respectively). In the subgroup of patients imaged within three hours of symptom onset, sensitivities for acute stroke were 27% for CT scanning and 76% for MRI, and specificities were 100% and 96%, respectively.
CONCLUSIONS: Although the authors suggest that their findings are consistent with a superiority of MRI over CT scanning for the imaging of acute stroke, MRI missed more patients with acute hemorrhagic stroke, which could have significant implications when selecting patients for thrombolytic therapy.--
Efficacy and Impact of Intravenous Morphine Before Surgical Consultation in Children With Right Lower Quadrant Pain Suggestive of Appendicitis - A Randomized Controlled Trial
Received 15 April 2007; accepted 19 April 2007. published online 28 June 2007.
The evidence supporting the use of analgesia in children with abdominal pain suggestive of appendicitis is limited. The objectives of the study are to evaluate the efficacy of morphine before surgical consultation in children presenting to the pediatric emergency department (ED) with right lower quadrant pain suggestive of appendicitis and determine whether it has an impact on the time between arrival in the ED and the surgical decision.
All children between the ages of 8 and 18 years who presented to a pediatric ED with a presumptive diagnosis of appendicitis were eligible to be enrolled in a randomized double-blind placebo-controlled trial if the initial pain was at least 5 of 10 on a verbal numeric scale. Patients received either 0.1 mg/kg of intravenous morphine (maximum 5 mg) or placebo. The primary outcomes were (1) the difference in pain using a visual analog scale at baseline and 30 minutes after the completion of the intervention, analyzed by comparing the mean pain differences for the treatment versus placebo groups; and (2) the time between arrival in the ED and the surgical decision, analyzed by comparing the median delay for the 2 groups.
Ninety patients with a suspected diagnosis of appendicitis were randomized to receive morphine or placebo. Both groups were similar in terms of demographics, medical history, physical findings, emergency physician assessment of the probability of appendicitis, and initial pain score. There was no important difference in the decrease of pain between the morphine (n=45) and placebo (n=42) groups 30 minutes after the intervention: 24±23 mm and 20±18 mm, respectively (Δ 4 mm [95% confidence interval [CI] −5 to 12 mm]). There was also no important difference in the time between arrival in the ED and the surgical decision: median 269 minutes (95% CI 240 to 355 minutes) for morphine and 307 minutes (95% CI 239 to 415 minutes) for placebo (Δ −34 minutes [95% CI −105 to 40 minutes]).
The use of morphine in children with a presumptive diagnosis of appendicitis did not delay the surgical decision. In our group of patients, however, morphine at a dose of 0.1 mg/kg was not more effective than placebo in diminishing their pain at 30 minutes.
- for men, PBW = 50.0 + 0.91 (height in centimeters - 152.4); and
- for women, PBW = 45.5 + 0.91 (height in centimeters - 152.4).
Common causes of ARDS are
- sepsis (with or without a pulmonary source),
- trauma, aspiration,
- multiple blood transfusions,
- inhalation injury, and
- certain types of drug toxicity.
Sudden hearing loss (SHL) is defined as greater than 30 dB hearing reduction, over at least three contiguous frequencies, occurring over a period of 72 hours or less. Some patients describe that the hearing loss was noticed instantaneously in the morning and others report that it rapidly developed over a period of hours or days. The severity of the hearing loss however varies from one patient to another and only one ear is usually affected. There have been some reports of involvement of both ears with SHL. Tinnitus is usually reported in patients with SHL loss and vertigo can be present in 40% of cases. The incidence of SHL has been reported to be 5-20 per 100,000 person per year and accounts for 1% of all sensorineural hearing loss cases. Males are equally affected as females. The average age at onset is reported to be 46 to 49 years with increasing incidence with age.
What Causes Sudden Hearing Loss?
There are many causes for sudden hearing loss which include infectious, circulatory, inner ear problems like meniere’s disease, neoplastic, traumatic, metabolic, neurologic, immunologic, toxic, cochlear, idiopathic (unknown cause) and other causes. Unfortunately, even after a thorough search for a possible pathology, the cause of sudden hearing loss remains unknown in most patients.
How is Sudden Hearing Loss Diagnosed?
Evaluation usually begins with a careful history and physical examintion looking for potential infectious causes such as otitis media, systemic diseases and exposure to known ototoxic medications. In essence, SHL is diagnosed by documenting a recent decline in hearing. This generally requires an audiogram. Blood studies are usually performed in an attempt to rule potentially systemic causes of SHL including syphilis, Lyme disease, metabolic, autoimmune, and circulatory disorders. Magnetic resonance imaging (MRI) of the brain is recommended to rule out an acoustic neuroma which is reported to be existent up to 15% of patients with sudden hearing loss.
How is Sudden Hearing Loss Treated?
Due to the lack of a definite cause of sudden hearing loss, its treatment has been controversial. Over the years, this has included systemic steroids, antiviral medications, vasodilators, carbogen therapy either (alone or in combination) or no treatment at all. The no treatment option was based on the high reported rate of spontaneous recovery up to two third of cases.
- Type I - fracture through the physis (widened physis)
- Type II - fracture partway through the physis extending up into metaphysis
- Type III - fracture partway through the physis extending down into the epiphysis
- Type IV - fracture through the metaphysis, physis, and epiphysis -- can lead to angulation deformities when healing
- Type V - crush injury to the physis
請問：哪種 type 是 child abuse 中最常見的呢？
在正常的情況下 ionized Ca佔大約50%
所以ionized Ca的level就會越來越接近total calcium的level
In plasma, calcium exists in 3 different forms,
- (1) 50% as ionized or the biologically active form,
- (2) 45% bound to plasma proteins (mainly albumin), and
- (3) 5% complexed to phosphate and citrate
- Mild: Total Ca 10.5-11.9 mg/dL (2.5-3 mmol/L) or Ionized Ca 5.6-8 mg/dL (1.4-2 mmol/L)
- Moderate: Total Ca 12-13.9 mg/dL (3-3.5 mmol/L) or Ionized Ca 8-10 mg/dL (2-2.5 mmol/L)
- Hypercalcemic crisis: Total Ca 14-16 mg/dL (3.5-4 mmol/L) or Ionized Ca 10-12 mg/dL (2.5-3 mmol/L)
From: Vei Ken Seow;
Date: 2007/8/30 上午 7:34
一個很棒的surviving sepsis campaign網頁
Sepsis is systemic infection accompanied by a reaction that has been termed the systemic inflammatory response syndrome (SIRS). SIRS represents an acute inflammatory reaction with systemic manifestations caused by release into the bloodstream of numerous endogenous mediators of inflammation. SIRS can also be caused by acute pancreatitis and major trauma, including burns. It has previously been defined by 2 or more of the following:
- Temperature > 38° C or less than 35° C
- Heart rate > 90 beats/min
- Respiratory rate > 20 breaths/min or Paco2 less than 32 mmHg
- WBC count > 12,000 or less than 4,000 cells/μL or > 10% immature forms
Severe sepsis is sepsis accompanied by signs of failure of at least one organ. Cardiovascular failure is typically manifested by hypotension, respiratory failure by hypoxemia, renal failure by oliguria, and hematologic failure by coagulopathy.
Septic shock is severe sepsis with organ hypoperfusion and hypotension that are poorly responsive to initial fluid resuscitation.
答案是：Pearly Penile Papules (是珍珠雞，不是性病！)