Sunday, September 09, 2007

Lit Bits: September 9, 2007

From the recent medical literaure...

1. Cardioverting AF in Patients with Pacemakers

Aims: External cardioversion (ECV) of atrial fibrillation (AF) may damage implanted pacemaker and cardioverter-defibrillator (ICD) systems. This prospective study evaluated the safety and efficacy of ECV comparing mono- to biphasic shock waveforms in patients with implanted rhythm devices.

Methods and results: Patients with pacemaker or ICD systems and an indication for ECV were randomized to receive mono- or biphasic shocks. Systems were tested immediately before and after ECV, 1 h and 1 week later with respect to device and lead integrity. Forty-four patients (71 ± 10 years, 31 male; 29 pacemakers, 12 ICDs, three cardiac resynchronization systems) underwent ECV with antero-posterior paddle orientation (monophasic in 21 and biphasic in 23 patients). Pacing impedances were reduced immediately after ECV (atrial 402–392 , P less than 0.001; ventricular 517–496 , P = 0.001) and returned to baseline values within 1 week. Ventricular sensing was reduced immediately after ECV (12.4–11.6 mV, P = 0.004). There was no device or lead dysfunction in any patient. ECV was successful in 42/44 patients (95%), cumulative energy was significantly lower for biphasic compared with monophasic shocks (P = 0.001).

Conclusion: ECV for AF seems to be safe and effective in patients with implanted rhythm devices.

Manegold JC, et al. Eur Heart J 2007 28: 1731-1738.

2. Move Over Ranson: The Pancreatitis Outcome Prediction (POP) Score: A new prognostic index for patients with severe acute pancreatitis

Objective: Severe acute pancreatitis, defined as pancreatitis with distant organ dysfunction, is a condition carrying a high mortality and morbidity. Current outcome prediction scores are based on small populations, usually from single specialist centers. Some scores cannot be applied until several days into hospital admission. We thus sought to develop a new and more sensitive outcome prediction score-the Pancreatitis Outcome Prediction (POP) Score-for these high-risk patients.

Design: Retrospective cohort study of a large multicenter intensive care database. Setting: One hundred fifty-nine U.K. intensive care units. Patients: Participants were 2,462 patients admitted to intensive care units with severe acute pancreatitis.

Measurements and Main Results: Demographic, physiologic, and biochemical data collected within the first 24 hrs of intensive care unit admission were used to develop a risk prediction score using logistic regression. The six variables with the strongest relationship to hospital outcome-arterial pH, age, serum urea, mean arterial pressure, Pao2/Fio2 ratio, and total serum calcium (in order of decreasing impact)-produced a model with a prognostic discrimination (area under the receiver operating characteristic curve = 0.838) superior to other models. These six factors were used to develop an objectively weighted multivariate prognostic score ranging from 0 to 40 points.

Conclusions: Prognostic stratification of patients with severe acute pancreatitis requiring intensive care offers a useful audit tool to gauge unit performance and improve delineation of subsets for prospective trials. Prospective validation of this new outcome prediction score is required, preferably in different countries. The validity of the POP Score for either hospital or intensive care admission could also be tested and assessed for superiority over existing scores.

Harrison DA, et al. Critical Care Medicine. 35:1703-1708.

3. Bilateral and Unilateral Acute Otitis Media: Different Clinical Entities? Bilateral involvement is associated with more-severe disease.

Expectant management is an acceptable treatment approach for selected children with acute otitis media (AOM) and avoids overuse of antibiotics (Journal Watch Emergency Medicine Oct 20 2006). In two recent studies, researchers hypothesized that bilateral and unilateral AOM might have different clinical, demographic, and microbiologic features. Such features might assist clinicians in determining which patients are likely to benefit from antimicrobial therapy.

A study from Texas included 1216 cases with clinical characteristics of AOM in children up to age 16 years; 566 underwent tympanocentesis and culture of middle ear fluid. Fifty-eight percent of the cohort had bilateral disease. Children younger than 2 years were significantly more likely to have bilateral than unilateral disease, but bilateral or unilateral disease was not associated with ethnicity, gender, history of prior AOM, fever, or day-care attendance. Age and severity of tympanic membrane inflammation were independent predictors of bilateral disease. Viruses did not show a significant relation to laterality, but bacterial pathogens, in particular Haemophilus influenzae, were significantly more likely to be isolated from subjects with bilateral disease.

A study from Israel included 1026 children aged 3 months to 3 years; all underwent tympanocentesis. Sixty-one percent had bilateral AOM. Patients with bilateral disease were younger than those with unilateral disease (mean age, 10.6 vs. 11.8 months), but no differences in gender, ethnicity, or history of previous AOM were noted. Bacteria were more commonly isolated from cultures of middle ear fluid in patients with bilateral AOM than in those with unilateral AOM (83% vs. 67%). The microbiologic spectrum was similar to that in the other study, and again, H. influenzae was more common in bilateral than unilateral disease (63% vs. 42%). Clinical/otologic scores used for determining disease severity were higher in patients with bilateral AOM, and bilateral disease was an independent risk factor for more-severe disease.

Comment: These data provide no big surprises, but the consistency between the findings of the two studies strengthens the conclusions. Bilateral disease is strongly associated with age (less than 2 years) and degree of tympanic membrane inflammation/disease severity, two factors that clinicians already consider when deciding whether to start antimicrobial therapy. Based on these two studies, it is reasonable for clinicians to also consider bilateral ear involvement as indicative of more-severe disease that requires antimicrobial therapy.

— Jill M. Baren, MD, MBE, FACEP, FAAP. Published in Journal Watch Emergency Medicine August 10, 2007. Citation: McCormick DP et al. Pediatr Infect Dis J 2007 Jul; 26:583-8.

4. Simple Score Aids Pulmonary Embolism Therapy Decisions: Some Might be Candidates for Exclusive Outpt Therapy

By David Douglas. NEW YORK (Reuters Health) Aug 07 - Comparison of two prognostic models shows that one appears to be particularly effective in predicting short-term mortality in patients with acute pulmonary embolism (PE), and thus can aid selection of candidates for outpatient therapy, according to Spanish researchers.

"Our findings suggest that a simple clinical score identifies a subgroup of patients with acute symptomatic PE and a very low risk of short-term complications with standard anticoagulation," lead investigator Dr. David Jimenez told Reuters Health.

In the July issue of Chest, Dr. Jimenez, of Alcala di Henares University, Madrid, and colleagues note that they used the PE severity index (PESI) classes I to V and the Geneva low-risk and high-risk strata to categorize 599 patients with confirmed PE.

The PESI classified 36% of the patients as being low-risk, compared to 84% when the Geneva prediction score was used.

At 30 days, there were statistical similarities in the proportion of purportedly low-risk patients who experienced non-fatal recurrent thromboembolism or major bleeding. This amounted to 2.8% of PESI patients versus 4.2% of Geneva patients.

However, at 30 days, mortality in the PESI-selected low-risk group was 0.9% compared to 5.6% via Geneva scoring.

Thus, concluded Dr. Jimenez, the usefulness of PESI "for selecting low-risk patients for out-of-hospital treatment of acute PE should be addressed in a well-designed clinical trial."

Dr. Lisa K. Moores, author of an accompanying editorial, told Reuters Health that "the PESI includes objective, easily identifiable factors, which can be ascertained within minutes of presentation -- without the use of sophisticated diagnostic testing."

"If these results are further confirmed, we might avoid hospital admission in as many as 25% of patients with acute PE," Dr. Moores, of the Uniformed Services University of the Health Sciences, Bethesda, Maryland, added.

Chest 2007;132:24-30.

5. Corticosteroids Reduce Relapse After Asthma Attack

By Anne Harding. NEW YORK (Reuters Health) Aug 06 - A new Cochrane Collaboration review confirms that asthma patients fare better after an emergency department visit for an exacerbation if they receive corticosteroids upon discharge.

Dr. Brian Rowe of the University of Alberta in Edmonton and colleagues found patients given corticosteroids were 62% less likely to require additional care in the week after discharge, and 53% less likely to relapse within 21 days.

However, Dr. Rowe told Reuters Health, prescribing corticosteroids is just "one of a variety of things that physicians should be doing at discharge," including working with the patient to develop a management plan for their asthma.

Up to 16% of people who undergo emergency treatment for an asthma exacerbation will relapse within two weeks, the researchers note in their report.

While Canadian, US and UK guidelines recommend corticosteroids after asthma exacerbations, Dr. Rowe and his team point out, "there remains significant debate about the use, dosage, route and length of corticosteroid (or glucocorticoid) treatment of the asthmatic in the in- and out-patient setting."

To clarify the potential benefits of corticosteroids, the researchers looked at six trials including 374 adults and children who were treated with the drugs or placebo after being discharged from acute care, most frequently the emergency department.

The RR for relapse in the first week after discharge for patients given corticosteroids was 0.38, and 0.47 in the first three weeks. Patients were also 65% less likely to require hospitalization, while they used an average of 3.3 fewer activations of beta-2 agonists daily. There was no significant difference in pulmonary function or side effects between the two groups.

The review was unable to answer the question of which route of administration is preferable, Dr. Rowe noted, and could also not address the issue of the best dosage. He pointed out that Canadian doctors typically use 50 mg for seven to 10 days, while US doctors prescribe 40 mg for the same time period, largely because 50 mg pills are available in Canada while 40 mg tablets are the US standard.

"Our feeling is that it's probably not so important how much you give but whether you give it or not," Dr. Rowe said.

Cochrane Database Syst Rev 2007;3.

6. A Prospective Evaluation of Shortened Course Oral N-Acetylcysteine for the Treatment of Acute Acetaminophen Poisoning

Betten DP, et al. Ann Emerg Med. 2007;50:272-279.

Study objective
Treatment with a shortened duration of oral N-acetylcysteine (20 to 48 hours) after acute acetaminophen poisoning is effective in the prevention of subsequent hepatic failure and death when administered to individuals meeting appropriate laboratory criteria.

Individuals with a potentially toxic acetaminophen ingestion according to serum acetaminophen levels were identified prospectively using a large statewide poison control system database throughout a 12-month period. N-acetylcysteine was administered for a minimum of 6 doses (20 hours), after which laboratory studies were obtained. Discontinuation of N-acetylcysteine was recommended by the poison center when 2 criteria were met: serum acetaminophen was undetectable (less than10 μg/mL) and liver test results were normal (serum aminotransferase, international normalized ratio). A follow-up questionnaire was administered to individuals treated with N-acetylcysteine for 48 hours or less to ascertain the presence of symptoms consistent with progressive hepatotoxicity.

Of 205 acutely poisoned individuals treated with N-acetylcysteine for 48 hours or less, 195 were successfully contacted after discharge, and 187 of 195 (95.9%) reported no symptoms consistent with hepatic failure. Eight individuals (4.1%) reported abdominal pain or vomiting; however, none received further N-acetylcysteine treatment or additional hospitalization.

A shortened duration of treatment with N-acetylcysteine (20 to 48 hours) may be an effective treatment option in individuals considered to be at no further risk of developing liver toxicity according to the fulfillment of appropriate laboratory criteria before N-acetylcysteine discontinuation.

7. ACEP’s New Clinical Policy on Acetaminophen Poisoning

Full-text (free):

8. Implantable Cardioverter Defibrillators Efficacious in Real-World Practice

Implantable cardioverter defibrillators reduce mortality associated with left ventricular systolic dysfunction, a systematic review in Annals of Internal Medicine concludes.

The federally funded review, undertaken to measure the effectiveness of ICDs "under usual clinical practice conditions," examined observational studies as well as randomized controlled trials. Randomized-trial data comprising over 8500 participants showed the devices lowered all-cause mortality by 20%; observational studies, including some 9450 subjects, showed an even greater reduction, 46%. (According to the authors, the higher benefit in observational studies may be due to physicians choosing healthier patients to receive ICDs.)

The authors say their investigation also affirms the current recommendation to "delay ICD implantation after acute coronary events or coronary revascularization."

Annals abstract:
Relevant ACC Guidelines:

9. Longer Ambulance Rides Linked with Increased Mortality

For patients with certain life-threatening emergencies, mortality increases with increasing distance from the emergency department, reports the Emergency Medicine Journal.

Researchers gathered data on some 10,300 ambulance calls in the U.K. over 5 years. All patients were unconscious, were not breathing, or had acute chest pain.

About 6% of patients died. Overall, the relative risk for death increased by 2% with each additional kilometer traveled. The association between mortality and distance was strongest for patients with respiratory problems. Adjustment for confounders such as age and illness severity did not significantly affect the findings.

The authors say their results support "an approximate 1% absolute increase in mortality associated with each 10-km increase in straight-line distance" from the emergency department, and they note that "closing local EDs could result in an increase in mortality for a small number of patients with life-threatening emergencies."

EMJ Abstract:

10. Very High-Dose IV Nitroglycerin Effective in Decompensated Heart Failure

By Martha Kerr. NEW YORK (Reuters Health) Aug 21 - Patients presenting to the emergency department with hypertensive, severely decompensated heart failure respond well to high-dose intravenous nitroglycerin. The strategy results in a lower risk of ICU admission and of endotracheal intubation, a team at Wayne State University in Detroit, Michigan, reports in the August issue of the Annals of Emergency Medicine.

Twenty-nine patients with severe decompensated heart failure were enrolled in an open-label, non-randomized trial of high-dose IV nitroglycerin. Eligible patients had a systolic pressure of 160 mm Hg or higher or a mean arterial pressure of 120 mm Hg or higher.

Patients received a 2 mg bolus of nitroglycerin, followed by a 20 micrograms/minute infusion every three to five minutes, with a maximum of ten doses. "This is 200 times the typical dose," lead investigator Dr. Phillip Levy told Reuters Health. The mean total dose of nitroglycerin administered in this study was 6.5 mg.

Endotracheal intubation was required in 13.8% of cases, bilevel positive airway pressure (BiPAP) ventilation in 6.9%, and ICU admission in 37.9%. Symptomatic hypotension developed in one patient and biomarker evidence of myocardial infarction was seen in 17.2% of patients.

An analysis of 45 historical controls with similar symptoms who did not receive high-dose nitroglycerin showed that 26.7% underwent endotracheal intubation, 20% had BiPAP and 80% were admitted to the ICU. MI biomarkers were observed in 28.9% of patients.

Ventricular filling is impaired in heart failure with hypertension, Dr. Levy explained. "High-dose nitroglycerin decreases preload enough so that ventricular filling is improved and the heart pumps more effectively."

Dr. Levy said that cardiac output is increased by about one-third. The short half-life allows any nitroglycerin-induced episodes of severe hypotension to self-correct, he noted.

"We think that the improved ventricular filling allows the fluid to get off the lung more quickly," which would explain the reduction in endotracheal intubation seen in the study group compared with controls, Dr. Levy surmised.

"The next step is a randomized, controlled trial conducted at multiple centers ... We need to ensure that the results are generalizable to all patients with heart failure." Approximately 90% of patients in this study were black, which is a group at high risk for hypertension and which may skew the findings, he pointed out.

Ann Emerg Med 2007;50:144-152.

11. Antibiotic Use for ED Patients With URIs: Prescribing Practices, Patient Expectations, and Patient Satisfaction

Ong S, et al. Ann Emerg Med. 2007;50:213-220.

Study objective
Physicians often prescribe antibiotics to patients even when there is no clear indication for their use. Previous studies examining antibiotic use in acute bronchitis and upper respiratory infections have been conducted in primary care settings. We evaluate the factors that physicians in the emergency department (ED) consider when prescribing antibiotics (eg, patient expectations) and the factors associated with patient satisfaction.

Ten academic EDs enrolled adults and children presenting with symptoms consistent with upper respiratory infection. Enrolled patients were interviewed before their physician encounter and were reinterviewed before discharge and 2 weeks later. Physicians were interviewed about factors that influenced their management decisions, including their perceptions of patients’ expectations. Patients with a single diagnosis of uncomplicated acute bronchitis or upper respiratory infection were included for analysis.

Of 272 patients enrolled, 68% of bronchitis patients and 9% of upper respiratory infection patients received antibiotics. Physicians were more likely to prescribe antibiotics when they believed that patients expected them (odds ratio [OR] 5.3; 95% confidence interval [CI] 2.9 to 9.6), although they were able to correctly identify only 27% of the patients who expected antibiotics. Satisfaction with the ED visit was reported by 87% of patients who received antibiotics and 89% of those not receiving antibiotics. Satisfaction with the visit was reported by 92% of patients who believed they had a better understanding of their illness but only by 72% of those who thought they had no better understanding (OR 4.4; 95% CI 2.0 to 8.4).

Physicians in our academic EDs prescribed antibiotics to 68% of acute bronchitis patients and to fewer than 10% of upper respiratory infection patients. Physicians were more likely to prescribe antibiotics to patients who they believed expected them, although they correctly identified only about 1 in 4 of those patients. Patient satisfaction was not related to receipt of antibiotics but was related to the belief they had a better understanding of their illness.

12. “Poachers and Dabblers?”: ASA President’s Incautious Comment Riles Emergency Physicians

Salaries and sedation were a central theme of the “21st Century Anesthesiology – Preparing for the Future Paradigm” presentation at the Practice Management Conference of the American Society of Anesthesiologists (ASA) last January.

Slide illustrations reflected the warnings ASA president Mark J. Lema issued to his colleagues. “What are the Current Issues Challenging the Status Quo?” one slide asked, followed by this list of answers:

“Provider Shortage/Aging Population”;

“Salary/Payment Problems”; and

“Poachers and Dabblers.”

Elaborating on the final point, another slide named the perpetrators eroding the anesthesiologists’ profession by administering propofol sedation.

“Dabblers” were the endoscopists, dentists and cosmetic surgeons.

But what group topped Lema’s “Poacher” list? “ER MDs (emergency surgery).”

Other “Poachers” were hospitalists and critical care physicians. Emergency physicians have been aware of the long-running ASA disputes with elective surgery specialties, and even dentists, over who should be administering propofol and under what conditions.

Emergency physicians, though, did not expect to find themselves as the new top target in the campaigns by the ASA and related groups to make propofol sedation the exclusive domain of anesthesiologists…

For the rest of the article (free):

13. Probiotics for treatment of acute diarrhoea in children: randomised clinical trial of five different preparations

Canani RB, et al. BMJ 2007;335.

Objective: To compare the efficacy of five probiotic preparations recommended to parents in the treatment of acute diarrhoea in children.

Design: Randomised controlled clinical trial in collaboration with family paediatricians over 12 months. Setting: Primary care. Participants Children aged 3-36 months visiting a family paediatrician for acute diarrhoea.

Intervention: Children's parents were randomly assigned to receive written instructions to purchase a specific probiotic product: oral rehydration solution (control group); Lactobacillus rhamnosus strain GG; Saccharomyces boulardii; Bacillus clausii; mix of L delbrueckii var bulgaricus, Streptococcus thermophilus, L acidophilus, and Bifidobacterium bifidum; or Enterococcus faecium SF68.

Main outcome measures: Primary outcomes were duration of diarrhoea and daily number and consistency of stools. Secondary outcomes were duration of vomiting and fever and rate of admission to hospital. Safety and tolerance were also recorded.

Results: 571 children were allocated to intervention. Median duration of diarrhoea was significantly shorter (P less than 0.001) in children who received L rhamnosus strain GG (78.5 hours) and the mix of four bacterial strains (70.0 hours) than in children who received oral rehydration solution alone (115.0 hours). One day after the first probiotic administration, the daily number of stools was significantly lower (P less than 0.001) in children who received L rhamnosus strain GG and in those who received the probiotic mix than in the other groups. The remaining preparations did not affect primary outcomes. Secondary outcomes were similar in all groups.

Conclusions: Not all commercially available probiotic preparations are effective in children with acute diarrhoea. Paediatricians should choose bacterial preparations based on effectiveness data.

14. How Quickly Do Systematic Reviews Go Out of Date? A Survival Analysis

Shojania KG, et al. Ann Intern Med. 2007;147:224-233.

Clinicians often use systematic reviews to obtain current evidence to guide clinical decisions and health care policy. Shojania and coworkers studied 100 quantitative systematic reviews to see how quickly the conclusions changed as new evidence became available. Conclusions about the effectiveness or harms of therapies frequently changed soon after publication of the systematic review. The median survival time without a change in the conclusions was 5.5 years. Significant new evidence had become available within 2 years for 23%. The evidence supporting preferred clinical practices is unstable.


15. Physician Scores on a National Clinical Skills Examination as Predictors of Complaints to Medical Regulatory Authorities

Tamblyn R, et al. JAMA. 2007;298:993-1001.

Context: Poor patient-physician communication increases the risk of patient complaints and malpractice claims. To address this problem, licensure assessment has been reformed in Canada and the United States, including a national standardized assessment of patient-physician communication and clinical history taking and examination skills.

Objective: To assess whether patient-physician communication examination scores in the clinical skills examination predicted future complaints in medical practice.

Design, Setting, and Participants: Cohort study of all 3424 physicians taking the Medical Council of Canada clinical skills examination between 1993 and 1996 who were licensed to practice in Ontario and/or Quebec. Participants were followed up until 2005, including the first 2 to 12 years of practice.

Main Outcome Measure: Patient complaints against study physicians that were filed with medical regulatory authorities in Ontario or Quebec and retained after investigation. Multivariate Poisson regression was used to estimate the relationship between complaint rate and scores on the clinical skills examination and traditional written examination. Scores are based on a standardized mean (SD) of 500 (100).

Results: Overall, 1116 complaints were filed for 3424 physicians, and 696 complaints were retained after investigation. Of the physicians, 17.1% had at least 1 retained complaint, of which 81.9% were for communication or quality-of-care problems. Patient-physician communication scores for study physicians ranged from 31 to 723 (mean [SD], 510.9 [91.1]). A 2-SD decrease in communication score was associated with 1.17 more retained complaints per 100 physicians per year (relative risk [RR], 1.38; 95% confidence interval [CI], 1.18-1.61) and 1.20 more communication complaints per 100 practice-years (RR, 1.43; 95% CI, 1.15-1.77). After adjusting for the predictive ability of the clinical decision-making score in the traditional written examination, the patient-physician communication score in the clinical skills examination remained significantly predictive of retained complaints (likelihood ratio test, P less than .001), with scores in the bottom quartile explaining an additional 9.2% (95% CI, 4.7%-13.1%) of complaints.

Conclusion: Scores achieved in patient-physician communication and clinical decision making on a national licensing examination predicted complaints to medical regulatory authorities.

16. Paramedics Overinflate Endotracheal Tube Cuffs

Every paramedic in this study inflated the cuff above the safe limit, and 87% could not detect an overinflated cuff by palpation of the pilot balloon.

Overinflation of an endotracheal tube (ETT) cuff can lead to severe complications, including tracheal necrosis, laryngeal nerve palsy, and tracheo-esophageal fistula, whereas underinflation can lead to inadequate ventilation from air leaks and aspiration. In a prospective, observational, cross-sectional simulation study, researchers assessed paramedics’ ability to inflate an ETT cuff to a safe pressure and to estimate the pressure of previously inflated cuffs by palpation of the pilot balloon.

After performing a simulated intubation, each participant assessed cuff pressure, and then a researcher measured actual pressure using a cuff inflation device. In a second phase of the study, participants palpated, in random order, nine ETT pilot balloons with pressures ranging from 0 to 120 cm H2O and indicated whether the pressure was too low, appropriate, or too high.

The 53 participating paramedics had an average career length of 6.6 years and performed endotracheal intubation an average of 3.6 times per year. Every participant inflated the ETT cuff above the safe pressure limit of 25 cm H2O, and, in 66% of cases, ETT cuff pressure was greater than the upper limit of measurement (120 cm H2O). Most participants (87%) could not detect an overinflated ETT cuff by palpation, and no participant identified all overinflated cuffs. The authors suggest that clinicians consider using a commercial ETT cuff inflator to achieve optimal pressures and a manometer to assess for safe results.

Comment: Although these dismal results might not be reproduced in larger samples or in an emergency department setting, they should remind us to pay attention to the dangers of overinflation or underinflation of an endotracheal tube cuff. Next time you intubate a patient or receive a patient who was intubated in the field, add assessment of the intracuff pressure to your postintubation algorithm of checking breath sounds, end-tidal carbon dioxide, and chest x-ray!

— Kristi L. Koenig, MD, FACEP. Published in Journal Watch Emergency Medicine August 30, 2007. Citation: Parwani V et al. Prehosp Emerg Care 2007; 11:307-11.

17. Thrombolysis for Acute Stroke: Much Talk, Little Action

From 1999 to 2004, tPA was administered to only 1.2% of acute ischemic stroke patients in the U.S.

Myriad studies have demonstrated the effectiveness and safety of tissue plasminogen activator (tPA) when administered under the appropriate circumstances and its deleterious effects when administered improperly or in small, nonacademic, nonstroke-center hospitals without specific policies and procedures for its use. These studies have given rise to two vocal camps of emergency physicians — one for and one against use of tPA — largely split according to the type of center in which the EP practices.

To identify hospital and patient characteristics associated with administration of tPA, researchers analyzed data from the Nationwide Inpatient Sample for 1999 through 2004. Of nearly 370,000 patients with acute ischemic stroke who were admitted through an emergency department, 4104 (1.12%) received tPA (intravenously in 90.1% and intra-arterially in 9.9%). Most hospitals (69.5%) did not use tPA. Among hospitals that did use tPA, the mean number of patients treated with it annually per hospital was 3.06 (range, 1 to 76). Patient factors that significantly decreased the chances of a patient being treated with tPA were older age (odds ratio, 0.43 for patients 85 compared with those less than 55), female sex (OR, 0.77), increased severity of illness (OR, 0.44 for patients with modified Charlson Index score 3 compared with those with score of 0), and black or Hispanic race/ethnicity (ORs, 0.54 and 0.79, respectively, compared with whites).

Comment: The database did not provide information about reasons for not giving tPA, other than presentation after the acceptable 3-hour window. The rate of tPA administration reported in this study is very low, with the hospitals divided mostly into those that rarely if ever use it and those that give it comparatively more often. The time has come for implementing systems of care that allow rapid screening and transport of eligible patients directly to centers that can safely administer tPA.

— Richard D. Zane, MD, FAAEM. Published in Journal Watch Emergency Medicine, August 24, 2007. Citation: Schumacher HC et al. Ann Emerg Med 2007; 50:99-107.

18. Survey Finds Significant Statistical Insecurity: Most physicians have no confidence in their own ability to use medical statistics.

The era of evidence-based medicine means that physicians are continuously exposed to statistical concepts, but a survey from Mayo Clinic documents how insecure most of us feel about using them.

Of 301 medical students, internal medicine residents, and internal medicine faculty members who completed a questionnaire (for a response rate of 64%), only a small minority agreed they had had adequate training in medical statistics (17%), could tell when the correct statistical methods were used in a study (23%), could conduct their own statistical analyses with confidence (15%), or could design their own research with confidence (28%). Although faculty were more likely to report confidence than trainees, even they were seldom confident using statistics independently, and even among respondents with extensive self-reported research experience, only 55% were confident conducting their own statistical analyses. Almost 80% of respondents felt a biostatistician should be centrally involved in most research.

Comment: This study's results certainly ring true: It seems only the rare physician is truly fluent in statistics and in the language of medical research. Further, while researchers may collaborate with biostatisticians on their projects, clinicians struggling to explain new studies to patients are on their own and often make big mistakes. The authors suggest that evidence-based medicine become the vehicle for more-effective training in biostatistics for all.

— Abigail Zuger, MD. Published in Journal Watch General Medicine August 29, 2007. Citation:
West CP and Ficalora RD. Mayo Clin Proc 2007; 82:939-43.

19. Admissions for Early MI Provide Opportunity to Flag High-Risk Relatives

Hospital admissions of patients with premature myocardial infarction could provide an opportunity to flag first-degree relatives for family counseling and heart disease screening, according to an analysis in BMJ.

Using data from previous case-control and cohort studies, researchers estimated that aggressively treating middle-aged people with a family history of early MI could have prevented 40% of premature MIs in England and Wales in 2004. In one study, the relative risk for early MI was 4.3 for male siblings of MI patients and 2.2 for female siblings; the researchers estimated that screening and treating these siblings could prevent about 1000 premature MIs over 5 years in England and Wales.

Previously, high-risk families had been targeted through questionnaires. The authors write that "wide coverage could be achieved by identifying relatives whenever someone is admitted to hospital for premature myocardial infarction. Such people may be motivated by their relative's illness to modify their lifestyle."

BMJ Abstract:

20. Food Additives Associated with Hyperactivity in Children

Common food additives may cause hyperactivity in children in the general population, according to a study published online in Lancet.

In a randomized crossover trial, 137 three-year-olds and 130 eight- or nine-year-olds consumed daily drinks of placebo, mix A (sodium benzoate and artificial food coloring), or mix B (similar to mix A, but with additional food coloring) for 6 weeks. Hyperactivity was evaluated using teacher and parent ratings, direct observation, and a computerized test.

Compared with placebo in adjusted analyses, mix A was associated with elevated hyperactivity scores among three-year-olds, while mix B was associated with elevated scores among eight- or nine-year-olds.

The authors write, "These findings show that adverse effects are not just seen in children with extreme hyperactivity (ie, ADHD), but can also be seen in the general population and across the range of severities of hyperactivity."

Lancet article (Free abstract with one-time registration; full text requires subscription):

21. Patient-Physician Communication Scores Predict Patient Complaints

Low communication scores on physician licensing exams predict patient complaints years later, reports a new study in JAMA.

In a longitudinal study, Canadian researchers looked at some 3400 physicians who took the Medical Council of Canada clinical skills examination from 1993 to 1996. Physicians could receive low scores on the communication portion by exhibiting "condescending, offensive, or judgmental behaviors, or ignoring patient responses."

Physicians who scored in the lowest quartile for communication had 4.26 patient complaints to the regulatory authority per 100 practice-years, compared with 2.51 per 100 practice-years for clinicians scoring in the top quartile. The communication score remained predictive of complaints after adjustment for the written clinical decision-making section of the test.

The authors recommend changing examinations to test communication skills more efficiently and earlier in a physician's training, and they suggest a minimum passing standard for communication skills.

JAMA article (Free abstract; full text requires subscription):