Tuesday, December 13, 2005

Lit Bits: December 13, 2005

From the recent medical literature...

1. Smallpox Vaccination.

In light of world-wide terrorist activities, is it advisable for emergency physicians to receive smallpox immunization? The short answer is No. This week’s JAMA catalogues some of the adverse events from the vaccine.

As you may recall, AAEM and SAEM jointly came out early with a firm recommendation that emergency physicians should not receive this vaccination in the absence of an identified case of smallpox. It appears their recommendation was prudent given the following excerpt: "A total of 38,885 smallpox vaccinations were administered, with a take rate of 92%. VAERS received 822 reports of adverse events following smallpox vaccination....

One hundred adverse events (12%) were designated as serious, resulting in 85 hospitalizations, 2 permanent disabilities, 10 life-threatening illnesses, and 3 deaths. Among the serious adverse events, 21 cases were classified as myocarditis and/or pericarditis and 10 as ischemic cardiac events that were not anticipated based on historical data. Two cases of generalized vaccinia and 1 case of postvaccinial encephalitis were detected."

URLs for the JAMA abstracts are below:

Adverse Events Associated With Smallpox Vaccination in the United States,
January-October 2003. Christine G. Casey; et al. JAMA 2005;294 2734-2743

Neurologic Adverse Events Associated With Smallpox Vaccination in the
United States, 2002-2004. James J. Sejvar; et al. JAMA 2005;294 2744-2750

2. Tell your patients: “It’s not bronchitis. It’s just a chest cold.”

Calling Acute Bronchitis a Chest Cold May Improve Patient Satisfaction with Appropriate Antibiotic Use. T. Grant Phillips, MD and John Hickner, MD, MS. J Amer Board Fam Practice 2005:18:459-463

Background: Overuse of antibiotics for acute respiratory infections is an important public health problem and occurs in part because of pressure on physicians by patients to prescribe them. We hypothesized that if acute respiratory infections are called "chest colds" or "viral infections" rather than "bronchitis," patients will be satisfied with the diagnosis and more satisfied with not receiving antibiotics.

Methods: Family medicine patients were presented with a written scenario describing a typical acute respiratory infection where they were given one of 3 different diagnostic labels: chest cold, viral upper respiratory infection, and bronchitis, followed by a treatment plan that excluded antibiotic treatment. Data was analyzed for satisfaction with the diagnosis and treatment plan based on the diagnostic label. A total of 459 questionnaires were collected.

Results: Satisfaction (70%, 63%, and 68%) and dissatisfaction (11% 13%, and 13%) with the diagnostic labels of cold, viral upper respiratory infection, and bronchitis, respectively, showed no difference (2 = 0.368, P = .832). However, more patients were dissatisfied with not receiving an antibiotic when the diagnosis label was bronchitis. A total of 26% of those that were told they had bronchitis were dissatisfied with their treatment, compared with 13% and 17% for colds and viral illness, respectively, (2 = 9.380, P = .009). Binary logistic regression showed no difference in satisfaction with diagnosis for educational attainment, age, and sex (odds ratio (OR) = 1.09, 1.00, 0.98, respectively), or for satisfaction with treatment (OR = 1.1, 1.02, 1.00, respectively).

Conclusions: Provider use of benign-sounding labels such as chest cold when a patient presents for care for an acute respiratory infection may not affect patient satisfaction but may improve satisfaction with not being prescribed an antibiotic.

3. COX 2 Inhibitors May Not be Safer for the Stomach

Non-steroidal anti-inflammatory drugs are among the most commonly prescribed drugs in England and Wales. They are widely used for musculoskeletal pain but can cause serious gastrointestinal side effects, including dyspepsia, peptic ulceration, and haemorrhage, and even result in death. Cyclo-oxygenase-2 inhibitors are a selective type of non-steroidal anti-inflammatory drug licensed in the United Kingdom for symptomatic relief in osteoarthritis and rheumatoid arthritis. They were developed to provide pain relief without the gastrointestinal side effects associated with traditional non-steroidal anti-inflammatory drugs, and their use is already recommended in UK national guidelines. The current treatment options include a traditional non-steroidal anti-inflammatory drug with an ulcer healing drug or a cyclo-oxygenase-2 inhibitor alone. However, trial data to support this, especially for elderly people, are sparse.

Considerable uncertainty surrounds the long term risks associated with cyclo-oxygenase-2 inhibitors outside the trial setting. Indeed, rofecoxib has been temporarily withdrawn owing to its adverse cardiovascular profile, and the safety profile of all cyclo-oxygenase-2 inhibitors is under review. The celecoxib long term arthritis safety study, which compared celecoxib with conventional non-steroidal anti-inflammatory drugs, has been criticised on the grounds of study design, analysis, selective presentation of results, increased rates of ulcers after six months of treatment, overall higher rates of extra gastrointestinal adverse events, and lack of data on long term safety. Although other smaller short term trials have shown fewer ulcers under endoscopy in patients taking cyclo-oxygenase-2 inhibitors, it is not known how these ulcers relate to clinical endpoints.

We undertook a population based nested case-control study, using a new general practice research database to determine the comparative risk of adverse upper gastrointestinal events in patients taking different cyclo-oxygenase-2 inhibitors and conventional non-steroidal anti-inflammatory drugs in primary care between 2000 and 2004.

Cyclo-oxygenase-2 inhibitors seem no better than conventional non-selective non-steroidal anti-inflammatory drugs in terms of the risk of an adverse upper gastrointestinal event. In a nested case-control study of more than 9000 cases of first peptic ulcer or haematemesis and almost 90 000 controls from 367 general practices throughout Great Britain, Hippisley-Cox and colleagues found that the risk of adverse events was increased with all NSAIDs included, selective and non-selective. Use of ulcer healing drugs reduced the increased risk of adverse events for all NSAIDs except diclofenac.

Hippisley-Cox J, et al. Risk of adverse gastrointestinal outcomes in patients taking cyclo-oxygenase-2 inhibitors or conventional non-steroidal anti-inflammatory drugs: population based nested case-control analysis BMJ 2005;331:1310-1316

Abstract: http://bmj.bmjjournals.com/cgi/content/abstract/331/7528/1310

4. Medical Management of Partial Small-Bowel Obstruction

Partial small-bowel obstruction caused by adhesions usually is managed initially by decompressing the gastrointestinal tract with a nasogastric (NG) tube, administering intravenous fluids, prohibiting oral intake, and waiting for spontaneous resolution. Researchers in Taiwan examined a more proactive approach in 128 patients with partial small-bowel obstructions presumed to be caused by adhesions from previous abdominal surgery.

Patients were randomized to two groups: One group received standard treatment with NG tube decompression, IV fluids, and nothing by mouth. The other group received similar standard treatment plus an oral regimen, given thrice daily, that consisted of magnesium oxide to stimulate bowel movement, simethicone to accelerate gas passage, and Lactobacillus acidophilus to promote digestion of undigested food in the bowel lumen. The proportion of patients who did not require surgery was significantly higher in the intervention group than in the control group (91% vs. 76%). In addition, the mean duration of hospital stay was significantly shorter in the intervention group (1 vs. 4 days). No obvious complications from the intervention were noted.

Comment: These results seem almost too good to be true: A safe and simple regimen appeared to dramatically hasten the resolution of partial small-bowel obstruction. Limitations of the study include confirmation of the diagnosis by plain radiography only and lack of double-blinding. Additional trials to confirm these results are warranted. At the time of publication, the full text of the original article was available free of charge.

— Allan S. Brett, MD. Published in Journal Watch November 29, 2005. Source: Chen S-C et al. Nonsurgical management of partial adhesive small-bowel obstruction with oral therapy: A randomized controlled trial. CMAJ 2005 Nov 8; 173:1165-9.

5. A Home-version of the Epley Maneuvers for Positional Vertigo

Positional maneuvers to treat benign paroxysmal positional vertigo (BPPV) can be performed in the clinician's office or at home. This randomized trial from Japan included 80 patients (age range, 24-85 years) with BPPV, diagnosed on the basis of typical symptoms and a positive Dix-Hallpike maneuver. Patients underwent an Epley procedure performed in the office, either alone or supplemented by modified Epley procedures performed three times daily at home.

At one week, repeat Dix-Hallpike maneuvers were negative in 72% of patients who were treated with a single office procedure and in 90% of patients who also performed home treatment, a significant difference. Complete resolution of symptoms was reported by 77% and 88% of patients in the two groups, respectively; this difference was not statistically significant.

Comment: These results suggest that a single office Epley procedure is effective in most patients, and that the addition of home treatment might "salvage" a small number of patients who don't respond to the office procedure.

At the time of this publication, diagrams and videos of the modified Epley procedure were available free of charge: A. Radtke et al. Neurology 2004;63:150-152. http://www.neurology.org/cgi/content/full/63/1/150
A good review article by JM Furman also provides diagrams of the Dix-Hallpike maneuver and the office Epley procedure. http://content.nejm.org/cgi/content/extract/341/21/1590

— Allan S. Brett, MD. Published in Journal Watch November 11, 2005. Source: Tanimoto H et al. Self-treatment for benign paroxysmal positional vertigo of the posterior semicircular canal. Neurology 2005 Oct 25; 65:1299-300.

6. The Difficult Stick.

Some patients just have difficult peripheral IV access. Before opening the central line kit, consider wheeling the US to the bedside and help identify those hard-to-find veins.

Ultrasonography-Guided Peripheral Intravenous Access Versus Traditional Approaches in Patients With Difficult Intravenous Access. Thomas G. Costantino, MD, et al. Ann Emerg Med 2005;46:456-461

Study objective
We assess the success rate of emergency physicians in placing peripheral intravenous catheters in difficult-access patients who were unsuccessfully cannulated by emergency nurses. A technique using real-time ultrasonographic guidance by 2 physicians was compared with traditional approaches using palpation and landmark guidance.

This was a prospective, systematically allocated study of all patients requiring intravenous access who presented to 2 university hospitals between October 2003 and March 2004. Inclusion criterion was the inability of any available nurse to obtain intravenous access after at least 3 attempts on a subgroup of patients who had a history of difficult intravenous access because of obesity, history of intravenous drug abuse, or chronic medical problems. Exclusion criterion was the need for central venous access. Patients presenting on odd days were allocated to the ultrasonographic-guided group, and those presenting on even days were allocated to the traditional-approach group. Endpoints were successful cannulation, number of sticks, time, and patient satisfaction.

Sixty patients were enrolled, 39 on odd days and 21 on even days. Success rate was greater for the ultrasonographic group (97%) versus control (33%), difference in proportions of 64% (95% confidence interval [CI] 39% to 71%). The ultrasonographic group required less overall time (13 minutes versus 30 minutes, for a difference of 17 [95% CI 0.8 to 25.6]), less time to successful cannulation from first percutaneous puncture (4 minutes versus 15 minutes, for a difference of 11 [95% CI 8.2 to 19.4]), and fewer percutaneous punctures (1.7 versus 3.7, for a difference of 2.0 [95% CI 1.27 to 2.82]) and had greater patient satisfaction (8.7 versus 5.7, for a difference of 3.0 [95% CI 1.82 to 4.29]) than the traditional landmark approach.

Ultrasonographic-guided peripheral intravenous access is more successful than traditional "blind" techniques, requires less time, decreases the number of percutaneous punctures, and improves patient satisfaction in the subgroup of patients who have difficult intravenous access.

7. Do Low-risk "Soft Rule-outs" Need a Monitored Bed?

Is It Necessary to Admit Low-Risk Patients With Suspected Acute Coronary Syndrome to Inpatient Telemetry Beds? Esther H. Chen, MD, Angela M. Mills, MD. Ann Emerg Med 2005;46:440-444.

Inhospital cardiac monitoring had been in use for more than 30 years before the American College of Cardiology published recommendations for its use in select patients in 1991. This position statement suggested that telemetry monitoring should be mandatory for the early hospital phase of patients with initially suspected acute myocardial infarction for detecting potentially life-threatening arrhythmias. Since then, the triage and treatment of acute chest pain patients has evolved such that this liberal admission policy to monitored units has been questioned. Liberal telemetry usage stresses the limited number of monitored beds, is costly, and may result in admission delays.

In 2004, the American Heart Association published guidelines recommending 12 to 24 hours of inpatient monitoring for chest pain patients with any sign of ischemia or infarction on the initial ECG and 1 evidence-based risk factor (low systolic blood pressure, rales, or exacerbation of ischemic heart disease) until acute myocardial infarction has been excluded by negative biomarker results. Theoretically, the rationale for using continuous cardiac monitoring in patients with suspected ischemia is to detect life-threatening dysrhythmias that may require emergency intervention.

Accordingly, there might be a select group of patients at such low risk for dysrhythmias or other cardiac complications that telemetry monitoring would not be clinically useful. Therefore, we searched the literature to determine whether telemetry monitoring was useful in the inpatient management of patients with potential acute coronary syndrome and whether there was a subset of patients who might be safely admitted to unmonitored beds.

The Bottom Line
A review of the available literature evaluating the clinical utility of inpatient telemetry showed that continuous cardiac monitoring played a small role in identifying patients at risk for adverse events or clinical deterioration. Chest pain patients with an initial normal or nonspecific ECG result and normal cardiac marker results and without recurrent chest pain are at low risk for adverse cardiac events, including life-threatening dysrhythmias, and therefore may not benefit from continuous cardiac monitoring. Although this is not a "zero-risk" strategy, because a few patients may develop a major adverse event, it would still be within the standard of care to admit these low-risk chest pain patients to an unmonitored unit.

8. A Fib in the ED. Just how do we manage these patients?

Analysis of Current Management of Atrial Fibrillation in the Acute Setting: GEFAUR-1 Study
Carmen del Arco, MD, et al (from Spain). Ann Emerg Med 2005;46:424-430.

Atrial fibrillation constitutes a growing health care problem because of its increasing prevalence, substantial complications, and associated costs. Although general agreement exists in literature about the role of stroke prophylaxis in these patients, the optimal strategy for the management of the arrhythmia remains uncertain: cardioversion and treatment with antiarrhythmic drugs to maintain sinus rhythm (rhythm control) or just control of the ventricular rate, allowing atrial fibrillation to persist.

A number of clinical trials have been conducted to determine the optimal medical management of atrial fibrillation, but these were not acute studies; they studied patients with minimally symptomatic long-term atrial fibrillation. Additionally, some reluctance exists to follow their conclusions in routine practice that patients' clinical characteristics and conditions of work greatly vary from those of randomized clinical trials.

Emergency departments (EDs) account for a large and increasing number of visits (>102 million in United States in 1999), mainly of aged persons and patients with cardiovascular diseases, important at-risk populations for atrial fibrillation. Additionally, atrial fibrillation is the most frequently managed arrhythmia in the ED, with a prevalence of 1.1% to 3.6% of the general medical ED visits. ED practice differs greatly from the "ideal" conditions of clinical trials and constitutes an accurate reflection of routine practice in patients' clinical profile and management. Thus, the study of the patterns of management of atrial fibrillation in this setting could help to identify areas for quality assessment and management improvement in the ED routine practice.

Goals of This Investigation
The objectives of this current analysis of the Spanish Atrial Fibrillation in Emergency Medicine (GEFAUR-1: Grupo para el Estudio de la FibrilaciĆ³n Auricular en URgencias) study were to determine the current management (rhythm or rate control) of atrial fibrillation, its effectiveness, and the factors related to the election of each strategy, identifying areas for management improvement, in a representative sample of the acute-setting daily practice.

Study objective
Limited information relative to the management of atrial fibrillation in the emergency department (ED) daily practice is available. This study evaluates current management of atrial fibrillation in this setting to identify areas for practice improvement.

This was a prospective multicenter observational study carried out in 12 EDs. Adults in whom atrial fibrillation was demonstrated in an ECG obtained in the ED were included. Clinical variables and atrial fibrillation management in the ED were prospectively collected by the treating physicians using a standardized questionnaire. Patients with rapid ventricular response (>100 beats/min) were considered eligible for rate control, and patients with recent-onset episodes (<48 hours) were eligible for rhythm control.

Of 1,178 patients, 41% presented with a rapid ventricular response and 21% had recent-onset episodes. Rhythm control was attempted in 42% of eligible patients, with antiarrhythmic drugs in 88% of cases (I-C drugs in 44% of patients; amiodarone in 43% of patients). Overall effectiveness of pharmacologic cardioversion was 63% (amiodarone 54.5%, flecainide 93%), whereas electrocardioversion was effective in 87.5% of cases. Rate control was performed in 68.3% of eligible patients (overall effectiveness 47.8%); digoxin was used in 67% of cases (effectiveness 45%). Both strategies were selected in 4.5% of cases, whereas no treatment for atrial fibrillation was performed in 60% of patients.

In our ED population, rate-control effectiveness is poor and rhythm control is not attempted in most recent-onset episodes. Methods to improve rate-control effectiveness, the selection of patients for rhythm control, and the use of electrocardioversion appear warranted.

9. Blood Cultures for Community-acquired Pneumonia??

JCAHO requires we obtain blood cultures before abx on admitted pts. Is this requirement evidence-based? Does it improve management?

Do Emergency Department Blood Cultures Change Practice in Patients With Pneumonia? Kennedy M, et al.Ann Emerg Med 2005;46:393-400

Study objective
Although it is considered standard of care to obtain blood cultures on patients hospitalized for pneumonia, several studies have questioned the utility and cost-effectiveness of this practice. The objective of this study is to determine the impact of emergency department (ED) blood cultures on antimicrobial therapy for patients with pneumonia.

We performed a prospective, observational, cohort study of consecutive adult (age =18 years) patients treated at an urban university ED between February 1, 2000 and February 1, 2001. Inclusion criteria were radiographic evidence of pneumonia, clinical evidence of pneumonia, and blood culture obtained. Blood cultures were classified as positive, negative, or contaminant based on previously established criteria. Additionally, data were collected on antimicrobial sensitivities, empiric antibiotic therapy, antibiotic changes, and reasons for changes.

There were 3,926 ED visits with blood cultures obtained for any reason, of which 3,762 (96%) were available for review. Of these, 414 of 3,762 (11%) patients met pneumonia study inclusion criteria, and blood cultures identified 29 of 414 (7.0%) patients with true bacteremia. In the 414 patients, blood culture results altered therapy for 15 patients (3.6%) with suspected pneumonia, of which 11 (2.7%) patients had their coverage narrowed; only 4 (1.0%) patients had their coverage broadened because of resistance to empiric therapy. For the 11 patients with bacteremia whose therapy was not altered, culture results actually supported narrowing therapy in 8 (1.9%) cases, but this was not done.

Blood cultures rarely altered therapy for patients presenting to the ED with pneumonia. More discriminatory blood culture use may potentially reduce resource utilization.

Free Full-text: http://download.journals.elsevierhealth.com/pdfs/journals/0196-0644/PIIS019606440500716X.pdf

10. Chronic A Fib. A Life Sentence?

Left Atrial Radiofrequency Ablation During Mitral Valve Surgery for Continuous Atrial Fibrillation: A Randomized Controlled Trial

George Doukas, FRCSI; et al. JAMA. 2005;294:2323-2329.

Context Although left atrial radiofrequency ablation (RFA) is increasingly used for the treatment of chronic atrial fibrillation during mitral valve surgery, its efficacy to restore sinus rhythm and any resulting benefits have not been examined in the context of an adequately powered randomized trial.

Objective To determine whether intraoperative RFA of the left atrium increases the long-term restoration of sinus rhythm and improves exercise capacity.

Design, Setting, and Patients Randomized, double-blind trial performed in a single UK tertiary referral center with enrollment between December 2001 and November 2003. A total of 101 patients referred for mitral valve surgery with at least 6 months’ history of uninterrupted atrial fibrillation were assessed for eligibility; 97 were enrolled. Patients were followed up for 12 months.

Intervention Patients were randomly assigned to undergo mitral valve surgery and RFA of the left atrium (n = 49) or mitral valve surgery alone (controls; n = 48).

Main Outcome Measures The primary outcome measure was presence of sinus rhythm at 12 months; secondary measures were patient functional status and exercise capacity (assessed by shuttle-walk test), left atrial contractility, and left atrial and left ventricular dimension and function and plasma levels of B-type natriuretic peptide.

Results At 12 months, sinus rhythm was present in 20 (44.4%) of 45 RFA patients and in 2 (4.5%) of 44 controls (rate ratio, 9.8; 95% CI, 2.4-86.3; P<.001). Restoration of sinus rhythm in the RFA group was accompanied by a greater improvement in mean (SD) shuttle-walk distance compared with controls (+94 [102] m vs +48 [82] m; P = .003) and a greater reduction in the plasma level of B-type natriuretic peptide (–104 [87] fmol/mL vs –51 [82] fmol/mL; P = .03). Patients randomized to receive RFA had similar rates of postoperative complications and deaths as control patients.

Conclusions Radiofrequency ablation of the left atrium during mitral valve surgery for continuous atrial fibrillation significantly increases the rate of sinus rhythm restoration 1 year postoperatively, improving patient exercise capacity. On the basis of its efficacy and safety, routine use of RFA of the left atrium during mitral valve surgery may be justified.

11. Hypertension Increases risk of Cognitive Decline in Elderly

December 6, 2005

LONDON (Agence de Presse Medicale for Reuters Health) - Uncontrolled hypertension appears to increase the risk of cognitive decline in the elderly, especially verbal fluency, according to a study published in Neuropsychology.

Christopher Brady and colleagues at Harvard Medical School and the Boston University School of Public Health examined the influence of age and hypertensive status on several cognitive tests via multiple regression in 357 men without dementia, with stable hypertensive status over 3 years and no comorbidities.

The men, who lived in the community and averaged 67 years old, were a subset of the 2,280 men in the Veteran Affairs Normative Aging Study, a longitudinal study that started in 1963 and added neuropsychological tests in 1993.

The findings showed that age was negatively associated with performance on all but the Digit Span Backward test. Older men in the sample with uncontrolled hypertension did significantly worse on specific tests of verbal fluency (generating words in a given category) and immediate recall of a word list (short-term memory).

In particular, with increasing age, uncontrolled hypertensives exhibited significantly larger decrements on category fluency (2.4 times greater) and immediate recall (1.3 times greater), compared with normotensives.

By the age of 80, men with uncontrolled hypertension could generate seven fewer words in a given category and recall about one and a half fewer words on average, than the other 80-year-old men in the study, the researchers said.

"The findings suggest that uncontrolled hypertension produces specific cognitive deficits beyond those attributable to age alone," they added.

The results are also consistent with other studies that suggest anti-hypertensive drugs do not hurt cognition -- men with controlled hypertension using antihypertensive drugs did as well as men without hypertension.

The researchers speculate that hypertension somehow exacerbates the normal effects of age on the frontal lobes, making it even harder to quickly retrieve information such as words.

The authors raise the possibility that the proportion of cognitive problems among older people with uncontrolled hypertension in the general population may actually be larger than seen in the study, because this sample used healthy men with no other health problems.

"Because a large proportion (37%) of older adults have uncontrolled hypertension and, furthermore, because hypertension prevalence increases, whereas hypertension control decreases, with increasing age, a substantial proportion of older adults may exhibit exacerbated age-related cognitive deficits that may be under-recognised in both research and clinical settings," they conclude.

Neuropsychology 2005;19:770-777.

12. C. difficile Causing Severe Diarrhea in Low-risk Patients

December 2, 2005

NEW YORK (Reuters Health) - Clinicians should be alert to cases of severe Clostridium difficile-associated disease (CDAD) in the absence of traditional risk factors, such as recent hospitalization or antimicrobial use, according to an article in the Morbidity and Mortality Weekly Report for December 2.

Following several reported cases of serious CDAD in otherwise healthy patients, the Pennsylvania and Philadelphia Departments of Health and the Centers for Disease Control and Prevention requested reports of peripartum and community-acquired CDAD.

Ten peripartum cases of CDAD were reported from Pennsylvania, New Hampshire, New Jersey and Ohio, and 23 community-acquired CDAD cases were reported from the Philadelphia area, with onset dates ranging from February 2003 to June 2005.

According to lead author Dr. E. Chernak with the Philadelphia Department of Public Health and colleagues, eight patients reported no exposure to antimicrobial agents within 3 months before CDAD onset. Seven cases occurred in patients who had close contact with a person with diarrheal illness.
Eight patients had bloody diarrhea, and 15 required hospitalization or an emergency department visit. Relapse occurred in 13 cases.

"Certain features of CDAD that have been uncommon in the past, such as close-contact transmission, high recurrence rate, young patient age, bloody diarrhea, and lack of antimicrobial exposure, might be changing," the authors maintain.

They recommend that patients with diarrhea lasting longer than 3 days or with bloody diarrhea or high fever should seek medical attention.

"The findings underscore the fact that antimicrobial exposure is not benign," the authors add, "and that judicious antimicrobial use in all health-care settings should continue to be emphasized."

Mor Mortal Wkly Rep CDC Surveill Summ 2005;54:1201-1205.