2007年10月31日 星期三

NEJM: PAOD and Herpes Labialis


Ho-Cheol Kang, M.D., Ph.D. Min-Young Chung, M.D., Ph.D. Chonnam National University Medical School Gwangju 501-746, South Korea【NEJM】



Julian W. Tang, M.D. Paul K.S. Chan, M.D. Chinese University of Hong Kong Hong Kong, China【NEJM】

Hip Fractures

NEJM Clinical Pearls 2007/10/31

Questions
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

NEJM Clinical Pearls 2007/10/31

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.

Questions
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.

2007年10月29日 星期一

【轉貼】Propofol Infusion Syndrome

Propofol Infusion Syndrome

花蓮慈濟醫院
藥劑科楊文琴藥師
神經外科 張玉麟醫師

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。

甲醇中毒

誤飲甲醇 先喝水催吐急送醫

◎朱芳業 [自由時報]

米酒幾乎已是國人生活文化的一部分,坐月子少不了它,料理少不了它,燉補少不了它,手頭緊的時候,飲酒作樂少不了它。日前驚傳有數例懷疑因飲用假米酒而發生甲醇中毒的案例,其引起的恐慌程度可說是草木皆兵,讓人聞酒色變。其實甲醇(俗稱木精或工業用酒精)的用途滿廣的,像亮光漆、油漆清除劑、擋風玻璃清潔劑、影印機溶液都用得到。 

甲醇中毒主要是發生於飲用含有甲醇的飲料或誤食含甲醇的防凍劑的人。甲醇極容易由腸胃道吸收,其吸收率幾近百分之百,而且在體內排泄的速度僅及乙醇的五分之一。一般攝入六十到二百五十西西即足以致命,文獻上亦有僅十五西西致死的案例。在人體內甲醇被酒精去氫酉每代謝為甲醛及甲酸,這就是引起視力傷害甚至失明,及代謝性酸中毒的元凶。其他像惡心、嘔吐、腹痛、頭痛、眩暈、抽搐及昏迷也是常見的症狀。 

當懷疑甲醇中毒時,可以氣相層析法檢測血中的甲醇濃度,一般血中濃度大於每百西西二十毫克即高度懷疑是甲醇中毒。另外,也可以測定血滲透壓來協助,一般會大於三百mOsm。當病患出現高滲透壓代謝性酸中毒合併陰離子間隙增加,即應考慮甲醇中毒的可能性。 

甲醇中毒的治療可以洗胃、體液補充、呼吸支持、控制抽搐、矯正酸血症、鹼化尿液、補充維生素B1及葉酸來治療,較嚴重的個案可以乙醇及血液透析治療。若不慎喝到含甲醇的假酒,緊急時若無法立即就醫,如果意識尚清楚,可先催吐喝水,並飲用濃度十七%的乙醇(紹興酒的酒精濃度約十七%)延緩甲醇的毒性傷害,大約分次喝三分之一瓶,同時儘速就醫。
(本文作者為署立桃園醫院家庭醫學科主治醫師、檢驗科主任)

更詳細的文章:
http://www7.vghtpe.gov.tw/epaper/article.asp?paperno=0049&serial=603

2007年10月24日 星期三

PCI versus CABG

NEJM Clinical Pearls / 200710/25

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.

2007年10月13日 星期六

瘀傷務必要記錄顏色!

Guidelines for color of bruises:
  1. Red to blue: about 1 to 2 days old
  2. Blue to purple: about 3 to 5 days old
  3. Green: about 6 to 7 days old
  4. Yellow to brown: about 8 to 10 days old
  5. Resolved: at least 13 to 28 days old
  6. 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.

2007年10月12日 星期五

FDA Warning: Haloperidol

Haloperidol is associated with a risk for torsades de pointes and QT prolongation.

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.

Comment:
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

Citation:
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)

2007年10月10日 星期三

插胸管要注意...

NEJM Teaching Pearls (Oct 11, 2007)

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.

Complications
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.

2007年10月7日 星期日

2007年10月5日 星期五

STOP sepsis bundle 利器

各位:我們 AICU 已經進了可連續測量 ScvO2 的 CVP catheter,
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。

更多參考:
http://er119test.blogspot.com/2007/07/stop-sepsis-bundle.html
http://er119test.blogspot.com/2007/07/stop-sepsis-bundle_11.html

--
張志華 敬上

小兒 endo 要插多深?

Best Method for Placing Pediatric Tubes to the Correct Depth

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.

2007年10月3日 星期三

成人百日咳並不少見

NEJM TEACHING TOPIC
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.

Questions
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.