Saturday, March 04, 2006

Lit Bits: March 4, 2006

From the recent medical literature...

1. Amiodarone Is Poorly Effective for the Acute Termination of Ventricular Tachycardia

Marill KA, et al. Ann Emerg Med 2006;47:217-224.

Editor’s Capsule Summary

What is already known on this topic? The advanced cardiac life support guidelines preferentially recommend amiodarone for termination of “stable” ventricular tachycardia.

What question did this study addressed? This retrospective study addressed the percentage of patients with stable monomorphic ventricular tachycardia who convert within 20 minutes after a single dose of amiodarone.

What does this study adds to our knowledge? Despite being a first-line recommendation of the advanced cardiac life support guidelines, amiodarone converted only a minority of the 28 patients with stable monomorphic ventricular tachycardia.

How might this change clinical practice? Knowledge of the poor response to amiodarone may result in increased use of other agents or electrical cardioversion without a prolonged trial of pharmacologic management.

Study objective
It is hypothesized that intravenous (IV) amiodarone is poorly effective for the acute termination of sustained monomorphic ventricular tachycardia because of the relatively slow onset of its Vaughn-Williams class III effect to prolong myocardial depolarization and the refractory period. This study is designed to determine the effectiveness and safety of IV amiodarone for the termination of sustained monomorphic ventricular tachycardia.

A retrospective case series was collected at 4 urban university-affiliated hospitals from September 1996 to April 2005 after institutional review board approval with waiver of informed consent. Emergency department (ED) patients treated with IV amiodarone for ventricular tachycardia were identified by ED treatment and hospital pharmacy billing records, International Classification of Diseases, Ninth Revision discharge codes, and ECG characteristics. All consecutive patients who received at least 150 mg amiodarone in 15 minutes or less for spontaneous sustained monomorphic ventricular tachycardia were eligible for inclusion.

Sustained monomorphic ventricular tachycardia was defined as a tachycardia with uninterrupted duration or rapid recurrence despite automatic internal cardiac defibrillator therapy for at least 5 minutes before amiodarone treatment, monomorphic morphology, rate greater than 120 beats/min, QRS duration greater than 120 ms, and subsequently determined to be ventricular tachycardia by ECG criteria (eg, atrioventricular dissociation), implanted device interrogation, or formal electrophysiology study. Measured outcomes included sustained termination of ventricular tachycardia within 20 minutes of initiation of amiodarone infusion and any documented adverse effects. Rates of successful termination and adverse effects and their 95% confidence intervals (CIs) were calculated. The presence or average values of potentially confounding predictors in patients with and without ventricular tachycardia termination after amiodarone were also calculated and compared.

Thirty-three patients were identified and included. Five patients received electrical therapy within 20 minutes of initiation of amiodarone infusion, and the response to amiodarone was unknown. Twenty-seven of the remaining 28 patients received 150 mg amiodarone, and the rate of successful ventricular tachycardia termination was 8 of 28, 29% (95% CI 13 to 49). Two of 33 patients, 6% (95% CI 1 to 20), required direct current cardioversion for presyncope or hypotension temporally associated with amiodarone treatment.

IV amiodarone, as currently administered, is relatively safe but ineffective for the acute termination of sustained ventricular tachycardia.

2. The pneumonia controversy: Hospitals grapple with 4 hour benchmark

Thompson D. Ann Emerg Med 2006;47: 259-261

Candy dishes filled with penicillin in triage. Topical antibiotics applied to the hands of patients with pneumonia-like symptoms. These are some of the ways hospitals are rumored to be “complying” with the 4-hour, door-to-antibiotic federal benchmark for community-acquired pneumonia.

No one would speak on the record about the candy dish, and the topical antibiotic was nervously chuckled off as an urban myth, but these shenanigans, even if apocryphal, illustrate the frustration with the measure, which is being linked to the bottom line.

Community-acquired pneumonia is 1 of 4 diagnoses identified by the federal Centers for Medicare and Medicaid Services (CMS) for quality improvement. The agency, which administered $483.8 billion in Medicaid and Medicare funding in 2004, identified several “core measures” to improve treatment of each condition, but the 4-hour antibiotic time in pneumonia has generated the most controversy.

“It’s a ridiculous number,” said Elizabeth Datner, the medical director of the Department of Emergency Medicine for the Hospital of the University of Pennsylvania, “especially when it may actually not even play out to show improved outcomes for patients.”

JCAHO and the evidence
The Joint Commission of Accreditation of Healthcare Organizations (JCAHO) based the standard on retrospective studies of tens of thousands of Medicare patients, showing slight decreases in 30-day mortality, length of stay, and readmission. CMS adopted it and required more than 3,800 hospitals across the country to report statistics on the timing of antibiotic administration in pneumonia. If they don’t, the hospitals will be penalized financially. The next step, already being tested with a pilot program, is to tie Medicaid funding to compliance with the core measures.

The remainder of this essay can be read in the attached pdf.

3. A new simplified immediate prognostic risk score for patients with AMI

B A Williams BA, et al. Emergency Medicine Journal 2006;23:186-192

Background: Immediate risk stratification of patients with myocardial infarction in the emergency department (ED) at the time of initial presentation is important for their optimal emergency treatment. Current risk scores for predicting mortality following acute myocardial infarction (AMI) are potentially flawed, having been derived from clinical trials with highly selective patient enrolment and requiring data not readily available in the ED. These scores may not accurately represent the spectrum of patients in clinical practice and may lead to inappropriate decision making.

Methods: This study cohort included 1212 consecutive patients with AMI who were admitted to the Mayo Clinic coronary care unit between 1988 and 2000. A risk score model was developed for predicting 30 day mortality using parameters available at initial hospital presentation in the ED. The model was developed on patients from the first era (training set—before 1997) and validated on patients in the second era (validation set—during or after 1997).

Results: The risk score included age (greater than 80, 2 points), sex (female, 3 pts), systolic blood pressure (greater than 140, 3 pts), admission serum creatinine (greater than 1.4, 1 pt), extent of ST segment depression (between 1 and 2 mm, 1 point; greater than 2mm, 3 pts), QRS duration (greater than or equal to 100ms, 1 pt), Killip class (more than 1, 3 pts), and infarct location (anterior, 1 pt). The predictive ability of the model in the validation set was strong (c = 0.78).

Conclusion: The Mayo risk score for 30 day mortality showed excellent predictive capacity in a population based cohort of patients with a wide range of risk profiles. The present results suggest that even amidst changing patient profiles, treatment, and disease definitions, the Mayo model is useful for 30 day risk assessment following AMI.

4. Statin and ß-Blocker Therapy and the Initial Presentation of Coronary Heart Disease

Alan S. Go, MD, et al (Kaiser DOR!). Ann Intern Med 2006;144:229-238.

We know little about factors that are associated with initial clinical presentations of coronary disease. This large case–control study compared characteristics of patients whose first clinical presentation of coronary disease was either acute myocardial infarction or stable exertional angina. Patients presenting with myocardial infarction rather than stable angina had received statins and ß-blockers less often; were more often men, smokers, and physically inactive; and more often had hypertension and diabetes. The study was observational and could not prove cause and effect. Several factors, including statin and ß-blocker therapy, might protect against higher-risk presentations of coronary disease. —The Editors

Background: Coronary atherosclerosis develops slowly over decades but is frequently characterized clinically by sudden unstable episodes. Patients who present with unstable coronary disease, such as acute myocardial infarction, may systematically differ from patients who present with relatively stable coronary disease, such as exertional angina.

Objective: To examine whether medication use or patient characteristics influence the mode of initial clinical presentation of coronary disease.

Design: Case–control study.

Setting: Large integrated health care delivery system in northern California.

Patients: Adults whose first clinical presentation of coronary disease was either acute myocardial infarction (n = 916) or stable exertional angina (n = 468).

Measurements: Use of cardiac medications before the event from pharmacy databases and demographic, lifestyle, and clinical characteristics from self-report and clinical and administrative databases.

Results: Compared with patients with incident stable exertional angina, patients with incident acute myocardial infarction were more likely to be men, smokers, physically inactive, and hypertensive but were less likely to have a parental history of coronary disease. Patients presenting with myocardial infarction were much less likely to have received statins (19.3% vs. 40.4%; P < 0.001) and ß-blockers (19.0% vs. 47.7%; P < 0.001) than patients presenting with exertional angina. After adjustment for potential confounders, recent use of statins (adjusted odds ratio, 0.45 [95% CI, 0.32 to 0.62]) and ß-blockers (adjusted odds ratio, 0.26 [CI, 0.19 to 0.35]) was associated with lower likelihoods of presenting with an acute myocardial infarction than with stable angina.

Limitations: This observational study did not have information on all possible confounding factors, including use of aspirin therapy.

Conclusion: Statin and ß-blocker use was associated with lower odds of presenting with an acute myocardial infarction than with stable angina. Additional studies are needed to confirm that these therapies protect against unstable, higher-risk clinical presentations of coronary disease.

5. A Randomized, Controlled Trial of Removable Splinting Versus Casting for Wrist Buckle Fractures in Children

PEDIATRICS Vol. 117 No. 3 March 2006, pp. 691-697

OBJECTIVE. Wrist buckle fractures are a frequent reason for emergency department visits. Although textbooks recommend 2 to 4 weeks of immobilization in a short arm cast, management varies. Treatment with both casts and splints is common, and length of immobilization varies. The objective was to determine if children with distal radius and/or ulna buckle fractures treated with a removable splint have better physical functioning than those treated with a short arm cast for 3 weeks.

METHODS. This was a randomized, controlled trial in the emergency department of an academic, tertiary care children's hospital. Participants were children 6 to 15 years of age with distal radius and/or ulna buckle fractures who were randomly assigned to treatment with a short arm cast for 3 weeks or a removable splint. Cast removal was at 3 weeks. A validated self-reported outcome tool, the Activities Scales for Kids performance version (ASKp), was used to measure physical functioning over a 4-week period. The main outcome was the ASKp score at 14 days postinjury.

RESULTS. We randomly assigned 113 patients, and 87 were included in the final analysis: 42 in the splint group and 45 in the cast group. Study groups were similar in age, gender, bone fractured, and dominant hand injured. There were significant differences in ASKp score at day 14 and change in ASKp from baseline at days 14 and 20, indicating better functioning in the splint group. Splinted children had less difficulty with bathing throughout the entire study. There were no significant differences in pain between groups as measured by visual analog scale. There were no refractures.

CONCLUSIONS. Children treated with removable splinting have better physical functioning and less difficulty with activities than those treated with a cast.

6. Treatment of Excessive Anticoagulation With Phytonadione (Vitamin K): A Meta-analysis

Kent J. DeZee, MD, MPH; et al. Arch Intern Med. 2006;166:391-397.

Background Patients taking oral anticoagulants with an international normalized ratio (INR) greater than 4.0 are at increased risk for bleeding. We performed a meta-analysis to determine the effectiveness of phytonadione (vitamin K) in treating excessive anticoagulation.

Methods The MEDLINE, EMBASE, and Cochrane Library databases were searched (without language restrictions) for articles published between January 1985 and September 2004. Randomized controlled trials or prospective, nonrandomized trials that used vitamin K to treat patients without major hemorrhage with an INR greater than 4.0 due to oral anticoagulant use were included. The primary outcome was achievement of the target INR (1.8-4.0) at 24 hours after vitamin K administration. Summary estimates were calculated using a random effects model.

Results Twenty-one studies (10 randomized and 11 prospective trials) were included. Among oral vitamin K treatment arms (4, n = 75), the proportion with a target INR at 24 hours was 82% (95% confidence interval [CI], 70%-93%), which was similar to intravenous vitamin K treatment arms (6, n = 69; target INR, 77%; 95% CI, 60%-95%). Treatment arms of subcutaneous vitamin K (3, n = 58; 31%; 95% CI, 7%-55%) and placebo/observation (2, n = 27; 20%; 95% CI, 0%-47%) were less likely to achieve target INR at 24 hours. Only 1 of 21 trials appropriately assessed for adverse events, so a summary estimate for bleeding risk could not be generated.

Conclusions Limited evidence suggests that oral and intravenous vitamin K are equivalent and more effective for excessive anticoagulation than simply withholding warfarin sodium. Subcutaneous vitamin K, however, is inferior to oral and intravenous vitamin K for this indication and is similar to placebo. Whether treatment with vitamin K decreases hemorrhagic events cannot be determined from the published literature.

7. Is atropine needed with ketamine sedation? A prospective, randomised, double blind study

P Heinz, et al. Emergency Medicine Journal 2006;23:206-209 (from Cambridge, UK, and Australia)

Objective: To compare atropine with placebo as an adjunct to ketamine sedation in children undergoing minor painful procedures. Outcome measures included hypersalivation, side effect profile, parental/patient satisfaction, and procedural success rate.

Methods: Children aged between 1 and 16 years of age requiring ketamine procedural sedation in a tertiary emergency department were randomised to receive 0.01 mg/kg of atropine or placebo. All received 4 mg/kg of intramuscular ketamine. Tolerance and sedation scores were recorded throughout the procedure. Side effects were recorded from the start of sedation until discharge. Parental and patient satisfaction scores were obtained at discharge and three to five days after the procedure, with the opportunity to report side effects encountered at home.

Results: A total of 83 patients aged 13 months to 14.5 years (median age 3.4 years) were enrolled over a 16 month period. Hypersalivation occurred in 11.4% of patients given atropine compared with 30.8% given placebo (odds ratio (OR) 0.29, 95% confidence interval (CI) 0.09 to 0.91). A transient rash was observed in 22.7% of the atropine group compared with 5.1% of the placebo group (OR 5.44, 95% CI 1.11 to 26.6). Vomiting during recovery occurred in 9.1% of atropine patients compared with 25.6% of placebo patients (OR 0.29, 95% CI 0.09 to 1.02). There was a trend towards better tolerance in the placebo group. No patient experienced serious side effects.

Conclusion: Ketamine sedation was successful and well tolerated in all cases. The use of atropine as an adjunct for intramuscular ketamine sedation in children significantly reduces hypersalivation and may lower the incidence of post-procedural vomiting. Atropine is associated with a higher incidence of a transient rash. No serious adverse events were noted.

8. New cardiovascular CT has high degree of agreement with coronary angiography

February 27, 2006. NEW YORK (Reuters Health) - Recently released 64-slice computed tomography technology has essentially the same accuracy as coronary angiography in coronary artery lumens with greater than 50% stenosis, according to study findings published in the American Journal of Cardiology for January 15.

Coronary angiography was compared with 64-slice CT in 66 sequential patients who were being evaluated for the presence of obstructive coronary artery disease. The patients underwent the two procedures within 30 days of each other. A total of 245 coronary arteries were evaluated with the two techniques.

Dr. Jeffrey J. Fine and colleagues at the South Carolina Heart Center in Columbia, SC, report that the sensitivity and specificity of 64-slice CT were 95% and 96%, and there was a positive predictive value of 97% and a negative predictive value of 92% for lesions causing greater than 50% stenosis. Nine vein grafts were required for revascularization in this study population.

"We found 100% agreement between 64-slice cardiovascular CT and catheterization among vein graft evaluations," the investigators report. "These metrics are vastly improved from the 16-slice generation and support 64-slice cardiovascular CT as a reliable diagnostic tool," Dr. Fine and colleagues conclude.

An editorial accompanying the study outlines some limitations with the use of multi-detector CT (MDCT) in the evaluation of coronary disease in asymptomatic patients. Dr. S. David Gertz and associates at the University of Texas Health Sciences Center in Houston, write: "Although MDCT can assess the thickness of the atherosclerotic wall and can readily identify calcific deposits, further plaque characterization (e.g., lipid pools and fibrous tissue), a prerequisite for the identification of most vulnerable lesions, is not yet a workable reality, even with the 64-slice machines in their current configurations."

Am J Cardiol 2006;97:173-174, 287-293.

9. U.S. Advisory Panel Endorses Rotavirus Vaccine for Infants

WebMD. By Maggie Fox. WASHINGTON (Reuters) Feb 22 - A new oral rotavirus vaccine, Rotateq (Merck and Co.), which protects 98% of infants against severe diarrhea, should be added to the schedule of immunizations for infants and young children, U.S. advisers said on Tuesday. The Advisory Committee on Immunization Practices, which advises the Centers for Disease Control and Prevention (CDC), voted unanimously after hearing from researchers who tested the vaccine. They said Rotateq vaccine, licensed earlier this month by the U.S. Food and Drug Administration, does not cause the same problems seen with an earlier vaccine withdrawn from the market in 1999.

Rotavirus is the leading cause of severe diarrhea in infants and young children and kills 500,000 young children a year globally. In the United States it affects 2.7 million children in an average year and 75% of children get diarrhea from rotavirus by the time they are 5 years old. "People assume it is a more severe disease in the developing world. It is not," said Dr. Paul Offitt, a vaccine expert and pediatrician at Children's Hospital in Philadelphia, whose work helped in the development of the vaccine.

"One out of five children, regardless of where you are, will have severe disease in the first five years of life. Here we can put in IVs. We keep children from dying in this country because we have the resources, but the diseases is severe everywhere."

Rotavirus puts between 55,000 and 70,000 children into the hospital in the United States each year and kills between 20 and 60 very young children. The U.S. Food and Drug Administration licensed Rotateq on February 3 for use in U.S. infants. It prevented any kind of rotavirus disease in 74% of babies tested and prevented the most severe illness in 98%. During the testing, Rotateq was not seen to cause any severe events, including intussusception. Wyeth's rotavirus vaccine was withdrawn because it apparently raised the risk of this complication.

The Merck vaccine is administered orally in three doses. "Children should receive the first dose by 12 weeks of age and should receive all doses of the vaccine by 32 weeks of age," according to a CDC statement. "There is insufficient data on safety and efficacy outside these age ranges."

10. Glucosamine Plus Chondroitin May Not Reduce All Osteoarthritis Pain

WebMD News Author: Laurie Barclay, MD. Feb. 23, 2006 — The combination of glucosamine and chondroitin does not reduce overall knee pain from osteoarthritis, except in a subgroup with moderate to severe pain, according to the results of a randomized study reported in the February 23 issue of the New England Journal of Medicine.

The editorialist emphasizes that if patients want to take this supplement, they should be advised to use glucosamine sulfate, not glucosamine hydrochloride, which was used in this study. "The dietary supplements glucosamine and chondroitin sulfate have been advocated, especially in the lay media, as safe and effective options for the management of symptoms of osteoarthritis," write Daniel O. Clegg, MD, from the University of Utah School of Medicine in Salt Lake City, and colleagues. "A meta-analysis of studies evaluating the efficacy of these supplements for osteoarthritis suggested potential benefit from these agents but raised questions about the scientific quality of the studies."

The multicenter, double-blind, placebo- and celecoxib-controlled Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) evaluated the efficacy and safety of glucosamine HCl and chondroitin sulfate as a treatment for knee pain from osteoarthritis. The investigators randomized 1583 patients with symptomatic knee osteoarthritis to receive 1500 mg of glucosamine HCI daily, 1200 mg of chondroitin sulfate daily, both glucosamine HCI and chondroitin sulfate, 200 mg of celecoxib daily, or placebo for 24 weeks. Patients were also permitted to take up to 4000 mg acetaminophen daily as rescue analgesia. Assignment was stratified on the basis of knee pain severity; 1229 patients had mild knee pain, and 354 patients had moderate to severe knee pain. The main end point was a 20% reduction in knee pain from baseline to week 24.

The mean age of patients was 59 years; 64% were women. Response rate, defined as 20% reduction in knee pain from baseline to week 24, was 60.1% for placebo, and it was 3.9 percentage points higher for glucosamine HCI (P = .30), 5.3 percentage points higher for chondroitin sulfate (P = .17), 6.5 percentage points higher for combined treatment (P = .09), and 10.0 percentage points higher for celecoxib (P = .008). For patients with moderate-to-severe knee pain at baseline, the rate of response was significantly higher with combined glucosamine HCI and chondroitin sulfate therapy than with placebo (79.2% vs 54.3%; P = .002). Adverse events were mild, infrequent, and similar in frequency among the groups.

"Glucosamine and chondroitin sulfate alone or in combination did not reduce pain effectively in the overall group of patients with osteoarthritis of the knee," the authors write. "Exploratory analyses suggest that the combination of glucosamine and chondroitin sulfate may be effective in the subgroup of patients with moderate-to-severe knee pain." Study limitations include the inability to rule out a positive effect for glucosamine HCI alone in the subgroup of patients with moderate-to-severe pain; inadequate power to detect increased risk of ischemic cardiovascular events with celecoxib or with glucosamine HCI in patients with diabetes; high placebo response rate and relatively mild degree of osteoarthritis pain limiting the ability to detect benefits of the treatments; insensitivity of outcome measures in identifying improvement; relatively small numbers of patients with moderate-to-severe knee pain, and use of supplement formulations that may not be commercially available.

"Our finding that the combination of glucosamine and chondroitin sulfate may have some efficacy in patients with moderate-to-severe symptoms is interesting but must be confirmed by another trial," the authors write. "In making therapeutic decisions, physicians and patients alike should be aware of our data suggesting that celecoxib has a much faster time to response than glucosamine, chondroitin sulfate, or both in combination. Continuing research is needed to establish the potential efficacy and increase our understanding of the biology, pharmacology, and pharmacokinetics of these agents."

The National Center for Complementary and Alternative Medicine and the National Institute of Arthritis and Musculoskeletal and Skin Diseases supported this study. Several authors report financial arrangements with McNeil Consumer and Specialty Pharmaceuticals and/or Pfizer. McNeil Consumer and Specialty Pharmaceuticals donated acetaminophen; Bioiberica, S.A., donated sodium chondroitin sulfate; and Ferro Pfanstiehl Laboratories donated a portion of the glucosamine HCI through Wilke Resources.

In an accompanying editorial, Marc C. Hochberg, MD, MPH, from the University of Maryland School of Medicine in Baltimore, notes that there is still no resolution to the question of whether nutritional supplements are effective for knee osteoarthritis. He points out other study limitations: celecoxib had no significant effect in the subgroup with moderate-to-severe knee pain at baseline; an attrition rate of at least 20% in the placebo group and in each of the dietary-supplement groups; the analyses did not incorporate data from all time points or use sophisticated methods for dealing with missing data; and use of glucosamine HCI rather than glucosamine sulfate, which is widely available as a dietary supplement in the United States.

"If patients choose to take dietary supplements to control their symptoms, they should be advised to take glucosamine sulfate rather than glucosamine hydrochloride and, for those with severe pain, that taking chondroitin sulfate with glucosamine sulfate may have an additive effect," Dr. Hochberg writes. "Three months of treatment is a sufficient period for the evaluation of efficacy; if there is no clinically significant decrease in symptoms by this time, the supplements should be discontinued. Furthermore, there is no evidence that these agents prevent osteoarthritis in healthy persons or in persons with knee pain but normal radiographs." Dr. Hochberg reports having received consulting fees from Pfizer and Merck and speaker's fees for Merck and Institut Biochimique. N Engl J Med. 2006;354:795-808, 858-860

11. Emergency Physicians' Prescribing of Asthma Controller Medications

Scarfone RJ, et al. PEDIATRICS Vol. 117 No. 3 March 2006, pp. 821-827

OBJECTIVES. To determine the frequency with which emergency department (ED) physicians prescribe long-term controller medications (LTCMs) for children with asthma, to assess ED physicians' awareness of and level of agreement with national guidelines for LTCM use, and to identify criteria ED physicians use to prescribe LTCMs and barriers to the use of LTCMs.

METHODS. A survey of all physician members of the American Academy of Pediatrics Section on Emergency Medicine who provide care for children in an ED was performed.

RESULTS. Surveys were returned by 391 (50%) of 782 physicians. The majority (80%) indicated that fewer than one half of children with persistent asthma were using LTCMs on ED arrival. Although 99% believe that children with persistent asthma should be treated with LTCMs, <20% provide LTCMs for the majority of such children at ED discharge. For 49%, the main reason for not prescribing these medications was the belief that this was the role of the primary care provider or asthma specialist. Practice setting, prior training, and annual patient volume were not associated significantly with prescribing LTCM. Patient's age and likelihood of compliance and physician's belief in efficacy and concerns about adverse effects were not important criteria in the decision to begin LTCM.

CONCLUSIONS. ED physicians often encounter children with persistent asthma who are not receiving LTCMs, they believe in the efficacy and safety of LTCMs, and they think that children with persistent disease should be treated with LTCMs, but they prescribe LTCMs infrequently.

12. Dispositional Optimism and the Risk of Cardiovascular Death: The Zutphen Elderly Study

Erik J. Giltay, PhD, MD; et al. Arch Intern Med. 2006;166:431-436.

Background: Dispositional optimism, defined in terms of life engagement and generalized positive outcome expectancies for one's future, may be related to lower cardiovascular mortality. We aimed to determine whether dispositional optimism is a stable trait over time and whether it is independently related to lower cardiovascular mortality in elderly men.

Methods: In a cohort study with a follow-up of 15 years, we included 545 (61.4%) of 887 men, aged 64 to 84 years, who were free of preexisting cardiovascular disease and cancer and who had complete data on cardiovascular risk factors and sociodemographic characteristics. Dispositional optimism was assessed using a 4-item questionnaire in 1985, 1990, 1995, and 2000. In Cox proportional hazards models, the first 2 years of observation were excluded.

Results: Optimism scores significantly decreased over 15 years, but showed temporal stability (reliability coefficients, 0.72 over 5 years and 0.78 over 15 years; P < .001). Optimists in 1985 had a hazard ratio for cardiovascular mortality of 0.45 (top tertile vs lowest tertile; 95% confidence interval, 0.29-0.68), adjusted for classic cardiovascular risk factors. The risk of cardiovascular death was inversely associated with increased tertiles of dispositional optimism (P < .001 for trend). Similar results were obtained using 1990 data after additional adjustment for depression (assessed by the Zung Self-rating Depression Scale).

Conclusion: Dispositional optimism is a relatively stable trait over 15 years and shows a graded and inverse association with the risk of cardiovascular death.

13. Local Anesthetic and Stylet Styles: Factors Associated With Resident Lumbar Puncture Success

Baxter AL, et al. PEDIATRICS Vol. 117 No. 3 March 2006, pp. 876-881

OBJECTIVE. To assess the effects of procedural techniques, local anesthetic use, and postgraduate training level on lumbar puncture (LP) success rates.

METHODS. In this prospective observational study, medical students and residents ("trainees") reported techniques used for infant LPs in an urban teaching emergency department. Data on postgraduate year, patient position, draping, total and trainee numbers of attempts, local anesthetic use, and timing of stylet removal were collected. Logistic regression analysis was used to identify predictors of successful LP, with success defined as the trainee obtaining cerebrospinal fluid with <1000 red blood cells per mm3.

RESULTS. We collected data on 428 (72%) of 594 infant LPs performed during the study period. Of 377 performed by trainees, 279 (74%) were successful. Local anesthesia was used for 280 (74%), and 225 (60%) were performed with early stylet removal. Controlling for the total number of attempts, LPs were 3 times more likely to be successful among infants >12 weeks of age than among younger infants (odds ratio [OR]: 3.1; 95% confidence interval [CI]: 1.2–8.5). Controlling for attempts and age, LPs performed with local anesthetic were twice as likely to be successful (OR: 2.2; 95% CI: 1.04–4.6). For infants 12 weeks of age, early stylet removal improved success rates (OR: 2.4; 95% CI: 1.1–5.2). Position, drape use, and year of training were not significant predictors of success.

CONCLUSIONS. Patient age, use of local anesthetic, and trainee stylet techniques were associated with LP success rates. This offers an additional rationale for pain control. Predictors identified in this study should be considered in the training of physicians, to maximize their success with this important procedure.

14. FDA Safety Changes: Marcaine

Sulfite Warning Added to Labeling for Injectable Bupivacaine Products (Marcaine)

On October 30, the FDA approved revisions to the container labels and carton labeling for bupivacaine HCl injection and bupivacaine plus epinephrine 1:200,000 injection (Marcaine and Marcaine with epinephrine, made by Hospira, Inc) to warn that these products contain 0.5-mg/mL of the antioxidant sodium metabisulfite as a preservative.

In susceptible patients, sulfites can cause allergic-type reactions, including anaphylactic symptoms and life-threatening asthma.

Bupivacaine is indicated for the production of local or regional anesthesia or analgesia for surgery, oral surgery procedures, diagnostic and therapeutic procedures, and obstetrical procedures.

15. Use of a prophylactic antiemetic with morphine in acute pain: randomised controlled trial

M Bradshaw and A Sen. Department of Emergency Medicine, Wrexham Maelor Hospital, Wrexham, UK. Emergency Medicine Journal 2006;23:210-213.

Objective: The aim of this study was to compare the incidence of nausea and vomiting in patients with acute pain treated with morphine along with prophylactic metoclopramide or placebo.

Method: A randomised controlled trial was carried out on patients requiring morphine for acute pain in the emergency department (ED) setting. Children under the age of 12, patients who had been vomiting or had already received prehospital analgesia, and those unable to give consent were excluded. All patients were given either metoclopramide (10 mg) or placebo (normal saline) followed by intravenous morphine. Pain scores (measured on a visual analogue scale) before and after morphine administration, all incidents of nausea or vomiting, the dose of morphine, and the patients’ demographic data were recorded. Fisher’s exact test was used for comparing the two groups of patients.

Results: A total of 259 patients were recruited. There were 123 patients in the metoclopramide group (age range 15–94 years; median age 53) and 136 patients in the placebo group (age range 17–93 years; median age 52.5). The overall incidence of nausea and vomiting in the whole study population was 2.7%, (1.6% in the metoclopramide group and 3.7% in the placebo group). The difference between the two groups was not statistically significant (Fisher’s exact test = 0.451; p = 0.3; z-test statistic = 1.02; 95% CI –6% to 2%).

Conclusion: When intravenous morphine is administered for acute pain, the overall incidence of nausea and vomiting is low, regardless of whether these patients are given prophylactic metoclopramide or not.

16. Treating secondary sleep disorders with melatonin is not effective

Exogenous melatonin is not effective in the management of secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag or shiftwork disorder. In a meta-analysis by Buscemi and colleagues (BMJ 18 February), six randomised controlled trials showed no evidence that melatonin had an effect on sleep onset latency in people with secondary sleep disorders and nine trials showed no effect on onset in people who had sleep disorders accompanying sleep restriction. There is evidence, however, that melatonin is safe with short term use.

17. Removal of C-spine protection by A&E triage nurses: a prospective trial of a clinical decision making instrument [Nexus]

E Pitt, D K Pedley, A Nelson, M Cumming and M Johnston. Accident and Emergency Department, Ninewells Hospital and Medical School, Dundee, UK. Emergency Medicine Journal 2006;23:214-215.

Objective: To investigate if triage nurses could safely apply a set of clinical criteria, removing hard collars and spinal boards at initial triage assessment.

Methods: The Nexus clinical decision rules were applied by trained triage nurses to patients who attended the department with cervical collars and /or on spinal boards. Patients were excluded if they were felt to be in need of immediate medical assessment. Data were collected on the time to nursing assessment, time to medical assessment and time spent restrained. Patients were followed up until discharge and their radiological diagnosis confirmed. Hospital records were checked to ensure that no patients re-presented with injuries that had been missed at initial assessment.

Results: In total, 112 patients were included in the study. Clinical criteria were met in 59 patients and their collar removed at triage assessment. For low risk patients, this reflects a mean reduction in time spent restrained of 23.3 minutes (p<0.005; 95% confidence interval 20.18 to 26.54). No patient who had a collar removed was found to have a significant injury.

Conclusions: Simple criteria can be applied by accident and emergency triage nurses to allow safe removal of cervical collars and spinal boards. The reduced time patients spent immobilised represents an important improvement in patient care.

18. Sham devices may have a greater placebo effect than inert pills

In patients with persistent arm pain, a sham acupuncture needle may enhance the placebo effect in comparison with an inert pill. In a randomised controlled trial of 270 adults, Kaptchuk and colleagues (BMJ 18 February) compared the two placebo treatments and found that a 10 point arm pain scale showed greater downward slopes in the sham device group than in the placebo pill group (-0.33 v -0.15; P = 0.0001). They found no differences for arm function and grip strength.

19. Gum Chewing May Speed Recovery From Postoperative Ileus

News Author: Laurie Barclay, MD. Feb. 22, 2006 — Gum chewing can speed recovery from postoperative ileus, according to the results of a prospective, randomized study reported in the February issue of the Archives of Surgery.

"An alternative approach to stimulate bowel function in the postoperative period following partial colon resection is sham feeding in the form of gum chewing," write Rob Schuster, MD, from Santa Barbara Cottage Hospital in California, and colleagues. "Gum is postulated to activate the cephalic-vagal reflex, which is usually enhanced by food, and to increase the production of gastrointestinal hormones associated with bowel motility."

Arch Surg. 2006;141:174-176