Wednesday, March 12, 2008

Lit Bits: March 12, 2008

From the recent medical literature...

1. Only One-Third of Adults Know Heart Attack Signs

Only about one-third of U.S. adults are aware of the five major warning signs of heart attacks, according to a CDC survey in MMWR.

The telephone survey of 72,000 people, conducted in 2005, found that, nationally:
• 48% recognize pain or discomfort in the jaw, neck, or back as a warning sign;
• 62%, feeling weak, lightheaded, or faint;
• 85%, pain or discomfort in the arms or shoulder;
• 92%, chest pain or discomfort;
• 93%, shortness of breath.

The numbers were even lower among non-Hispanic blacks and Hispanics, men, and those with less than a high school education. In addition, 86% said they would dial 911 if they thought someone was having a heart attack or stroke.

MMWR article (Free):

2. Patients Less Likely to Survive In-Hospital Cardiac Arrests on Nights, Weekends

Cardiac arrest during the night or on weekends places hospital patients at higher risk for death and complications, a JAMA article reports.

Using national registry data on nearly 87,000 adult cardiac arrests occurring between 2000 and 2007, researchers characterized the events by time-of-day and day-of-week. When compared with arrests that occurred during the day or evening hours, nighttime events (11 p.m. to 7 a.m.) showed significantly lower rates of survival to discharge, return of spontaneous circulation for more than 20 minutes, survival at 24 hours, and favorable neurologic outcome.
Rates on weekends were similar to those on weekday nights.

The authors write that, in searching for causes, "it is reasonable to focus on the potential for decreased physical and psychological performance on the part of the health care worker, different staffing patterns, and less patient surveillance during nights and weekends."

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

3. Increased Blood Pressure in the ED: Pain, Anxiety, or Undiagnosed HTN?

Tanabe P, et al. Ann Emerg Med. 2008;51:221-229.

It is unclear how often increased blood pressure in emergency department (ED) patients is a marker of chronic essential hypertension and how often it is a transient finding related to stress. So this study asked ‘how frequently is an increased blood pressure in ED patients without known hypertension sustained at home?’ Of 156 ED patients prospectively followed at a single urban site, half had sustained hypertension at home. ED blood pressure increase was not associated with increased anxiety or pain. How this might change clinical practice? Patients with increased blood pressure in the ED should be advised to have serial blood pressure checks so that essential hypertension can be confirmed or excluded.

Annals abstract:

4. Bacteria Continue to Evolve in Face of Iatrogenic Selection Pressure

A. Multidrug-Resistant E. Coli Emerging

Clinicians should be aware of the emergence of multidrug-resistant Enterobacteriaceae that produce extended-spectrum beta-lactamases (ESBLs), according to a review article in Lancet Infectious Diseases.

These bacteria are becoming important causes of urinary tract infections, and treatment failures are likely because of their broad resistance, the article says. A recent trend is community-acquired bloodstream infections caused by ESBL-producing bacteria, mostly E. coli. Though still rare, it's possible that in the near future, "clinicians will be regularly confronted with hospital types of bacteria causing infections in patients from the community," a situation similar to community-acquired MRSA.

Lancet ID abstract:

B. First Cases of Fluoroquinolone-Resistant N. meningitidis Reported

The first cluster of fluoroquinolone-resistant meningococcal disease in North America has been documented along the Minnesota-North Dakota border, according to a report in MMWR.

Three cases of disease resulting from resistant N. meningitidis have occurred there over the past year. The CDC says ciprofloxacin (Cipro) should not be used for chemoprophylaxis of close contacts of people with meningococcal disease in a 34-county area in the two states but can still be used elsewhere. In the affected area, the agency recommends use of rifampin, ceftriaxone, or azithromycin.

An editorial note says all cases of ciprofloxacin-resistant meningococcal disease and ciprofloxacin prophylaxis failures should be reported to the CDC as well as state and local health authorities.

MMWR article (Free):

5. Intravenous dexamethasone vs placebo as adjunctive therapy to reduce the recurrence rate of acute migraine headaches: a multicenter, double-blinded, placebo-controlled randomized clinical trial

Donaldson D, et al. Amer J Emerg Med. 2008;26:124-130.

Some physicians prescribe corticosteroids as adjunctive therapy for patients with migraine headaches to decrease the rate of rebound headache. The efficacy of this practice has not been tested. Our objective is to determine the efficacy of single-dose dexamethasone as adjunctive therapy for emergency medicine patients with migraine headache in preventing headache recurrence at 3 and 30 days posttreatment.

From November 2004 to November 2005, we conducted a multicenter, double-blinded, placebo-controlled randomized clinical trial of adult patients who met the International Headache Society definition of migraine headache. After informed consent, patients were randomly assigned to one of two groups: receiving either placebo or 24 mg dexamethasone intravenously. To ensure generalizability, all other aspects of patient care were left to the discretion of the emergency physician. Clinical and demographic information was obtained; and patients were subsequently contacted at both 3 and 30 days to determine headache recurrence, current functional disability, and need for return to the ED. Our primary outcome measures were the recurrence of migraine headache at 3 and 30 days. We used Fisher exact to test for statistical significance.

A total of 115 patients were enrolled, with 16 patients lost to follow-up at 3 days and 3 additional patients lost at 30 days. Baseline characteristics as well as adverse event profiles were equivalent in both study groups. At 3-day follow-up, 45% (95% confidence interval [CI] 31%-60%) of the placebo group had recurrence of their migraine compared with 35% (95% CI 24%-48%) in the dexamethasone group (P = .68). At 30-day follow-up, this relative reduction in migraine recurrence decreased to a 4% difference between the 2 groups (P = .68). Limitations include small sample size and significant proportion lost to follow-up.

A single dose of dexamethasone as adjunctive therapy for migraine headache does not decrease the recurrence of migraines at 3 or 30 days.

6. MRSA: Deadly Super Bug or Just Another Staph?

Talan DA. Ann Emerg Med. 2008;51:299-302.

Opening paragraphs
Commenting on an article by Klevens et al in the Journal of the American Medical Association that described the incidence of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections, an editorialist estimated that more patients died with invasive MRSA than died because of HIV/AIDS in the United States in 2005. Simultaneous reports of MRSA outbreaks among high school athletes and deaths in previously healthy children set off a media frenzy calling MRSA a deadly “super bug.” Certainly the emergency department (ED) would seem to be a good place to study the epidemiology of this new disease whose impact has been confused and sensationalized. In this issue of Annals, Pallin et al attempt to answer the question of whether MRSA infection is associated with more patients being treated in EDs with skin and soft tissue infections than in the past.

We already know that the ecology of skin and soft tissue infections has changed dramatically. Our ED-based emerging infections surveillance network, EMERGEncy ID NET, reported that MRSA caused 59% of skin and soft tissue infections among 422 adults treated at 11 geographically diverse US EDs in August 2004. Almost all isolates were the newly recognized community-associated MRSA USA 300, which contained genes for Panton-Valentine leukocidin toxin and carried staphylococcal cassette chromosome (SCCmec) type IV. Before this millennium, MRSA was rarely found in community-presenting infections. For example, we found no MRSA, either community-associated MRSA or the older health care–associated strain, in a bacteriologic study of 160 cutaneous abscesses among patients presenting to the ED from 1992 to 1994; methicillin-susceptible S aureus was the most common pathogen, found in 50%.

Although community-associated MRSA now is recognized to cause more of patients’ skin and soft tissue infections, does it cause more people to have skin and soft tissue infections? In other words, has the emergence of community-associated MRSA resulted in an increased burden of disease, not just a change in the strain-specific cause? This is the question that Pallin et al attempted to answer…

Closing paragraph
Community-associated MRSA is not a deadly super bug. It is more like an aggressive type of standard honeybee than the Africanized variety; more apt to sting, usually causing a mild and sometimes uncomfortable lesion that is infrequently more serious, but only rarely fatal. Although community-associated MRSA appears to be more efficient at causing infection in healthy individuals than methicillin-susceptible S aureus, particularly among groups with frequent skin-to-skin contact, most infections are uncomplicated skin and soft tissue infections. Patients with community-associated MRSA skin and soft tissue infections should be reassured that they have a good prognosis and many antibiotic treatment options, including several inexpensive oral drugs. Continued surveillance for invasive community-associated MRSA will help determine whether the low rate of more serious community-associated MRSA infections is increasing. Despite limitations, the Pallin et al findings are compelling and suggest that community-associated MRSA has resulted in a significantly increased burden of disease and that additional attention and resources should be directed to monitor, prevent, and control this emerging problem.

For the rest of the article:

7. Meta-Analysis Shows That Statins Reduce the Incidence and Recurrence of AF

Michael O'Riordan. from Heartwire — a professional news service of WebMD. February 20, 2008 — A study published this week provides a little more evidence that the benefit of statins extends beyond their ability to lower low-density lipoprotein (LDL) cholesterol levels [1]. In a new meta-analysis, investigators showed that the use of statins was significantly associated with a decreased risk of incidence or recurrence of atrial fibrillation (AF) in patients in sinus rhythm with a history of previous AF, those undergoing cardiac surgery, or those prescribed the drugs after an acute coronary syndrome (ACS).

In a paper published in the February 18, 2008 issue of the Journal of the American College of Cardiology, a special issue focusing on AF, Dr Laurent Fauchier (Centre Hospitalier Universitaire Trousseau, Tours, France) and colleagues note that the "beneficial effect seemed more marked in the prevention of AF recurrence than in primary prevention of AF" but cautioned against making too much of this finding as there was only a trend of benefit in these patients.

The meta-analysis included six studies with approximately 3500 patients in sinus rhythm. Three studies investigated the use of statins in patients with a history of paroxysmal AF or persistent AF undergoing electrical cardioversion, while the others investigated the use of statins in primary prevention of AF in patients undergoing cardiac surgery or following ACS. The follow-up in the six trials ranged from three to 26 weeks, and in five of the six studies, atorvastatin was the statin prescribed.

Treatment with a statin reduced the incidence and recurrence of AF 61% compared with placebo. While there were trends toward significance in primary- and secondary-prevention subset analyses, none of these reductions were statistically significant. The overall results were similar when investigators excluded the Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering (MIRACL) study, which was published only in abstract form. They note that the protective benefit of statins did not appear to be related to dose, as individual odds ratios were similar in the studies that used atorvastatin 40 mg and 80 mg to studies that used lower doses.

While the mechanisms of benefit are still unknown, Fauchier and colleagues note that statins reduce inflammation and that inflammation is involved in the "development, recurrence, and persistence of AF." They also note that some evidence suggests an association between AF and enhanced renin angiotensin system (RAS) activity. Other studies have also suggested a link between dyslipidemia and the RAS, and with statins reducing cholesterol levels, the drugs might downregulate the RAS and possibly explain the antiarrhythmic effects observed.

Still, large-scale, prospective, randomized clinical trials are needed to establish whether statins bring a similar benefit to those not part of the patient population in this meta-analysis and to explore whether the drugs might be an appropriate therapeutic option in all subgroups of patients for the management of AF, conclude the authors.

[1] Source: Fauchier L, et al. J Am Coll Cardiol. 2008;51:828-835.

8. Higher PEEP probably best for people with acute lung injury and respiratory distress syndrome

JAMA, Feb 13, 2008. Positive pressure ventilation is unphysiological and further damages the lungs of patients with acute lung injury and respiratory distress syndrome. Using a small tidal volume helps, and animal models suggest that a high positive end expiratory pressure (PEEP) can also improve outcome by stopping alveoli from collapsing at the end of each expiration. Proving it in humans is hard work, however, and two big trials recently reported no difference in mortality between groups of patients treated with higher and lower levels of PEEP.

The trials tested complex protocols that titrated PEEP according to either oxygenation or lung mechanics (pulmonary pressure and volume). In both, one group had end expiratory pressures of 15-16 cm H2O on day 1 and the other group had mean pressures of 8-10.1 cm H2O. The extra end expiratory pressure didn’t save lives, but it did seem to improve some measures of morbidity, including risk of hypoxaemia or organ failure and time on the ventilator.

At least two experts say these results are enough to support a strategy of higher PEEP for people with acute lung injury and acute respiratory distress syndrome. It is still possible that a subset of the sickest patients will survive longer, and for the rest it is fairly clear that this strategy does no harm.

JAMA 2008;299:637-45. Abstract:
JAMA 2008;299:646-55. Abstract:

9. Caution About Vasopressor Use in Hemorrhagic Shock

Use of vasopressors was associated with increased mortality 24 hours after injury.

Crystalloid resuscitation is a mainstay in the management of post-traumatic hemorrhagic shock, but excessive fluid administration might increase or aggravate coagulopathy, abdominal compartment syndrome, pulmonary and cardiac dysfunction, gastrointestinal ileus, and bowel anastomotic complications. These risks, coupled with hemorrhagic-shock research in animal models that has demonstrated a benefit of vasopressin and phenylephrine compared with crystalloid alone, have prompted increased exploration of the use of vasopressors. Investigators used data from a prospective multicenter cohort study (Inflammation and the Host Response to Injury program) to evaluate use of early vasopressor therapy and aggressive early crystalloid resuscitation in trauma patients.

Patients admitted to seven U.S. institutions between 2003 and 2007 were eligible if they were aged 16 to 90 and had a blunt mechanism of injury, systolic blood pressure less than 90 mm Hg prehospital or in the emergency department or elevated base deficit (6 mEq/L) in the ED, blood transfusion requirement within the first 12 hours of injury, and any body region other than the brain with an Abbreviated Injury Scale score 2. Mortality rates were compared between patients who did and did not receive early (within 12 hours of injury) vasopressor therapy (Levophed, phenylephrine, dopamine, or vasopressin) and between patients who did and did not receive aggressive early crystalloid resuscitation (16 L within 12 hours post-injury). Analyses were controlled for important physiologic, injury, resuscitation, and demographic parameters.

Among 921 patients, the overall mortality rate was 12% and the mean Injury Severity Scale score was 31. Use of vasopressors (any of the 4 studied) within 12 hours after injury, compared with no use of vasopressors, was associated with an increased mortality risk (hazard ratio, 1.81), as was use of vasopressors within 24 hours after injury (HR, 2.15). Aggressive early crystalloid resuscitation within 12 hours, compared with no use of crystalloid resuscitation, was associated with a reduction in mortality (HR, 0.59). In analysis by age (55 vs. those older than 55), the only significant finding was a protective effect of aggressive early crystalloid resuscitation in the younger group (HR, 0.54).

Comment: Data from this large prospective cohort demonstrate nearly doubled mortality in patients who received early vasopressor therapy compared with those who did not. However, patient management — notably the use of vasopressor therapy and the amount and rate of crystalloid resuscitation — was not controlled. A prospective, randomized, provider-blinded study is needed to definitively resolve this issue.

— John A. Marx, MD. Published in Journal Watch EM February 22, 2008. Citation: Sperry JL et al. J Trauma 2008;64:9.

10. The Claim: Stretching Can Prevent Soreness and Injury. Really??

By Anahad C’Connor. New York Times. February 26, 2008


Stretching — long promoted as a way to prevent injury, to reduce soreness and to speed post-exercise recovery — may not fulfill its promise. Over the years, scientists have found that stretching before or after a workout has little effect on either risk of injury or what is commonly known as delayed onset of muscle soreness, the discomfort that comes a day or more after challenging physical activity.

Numerous studies have reached this conclusion. One of the most recent and extensive reports was published in October in The Cochrane Database of Systematic Reviews. The report reviewed 10 randomized studies, which over all looked at the impact of stretching before and after exercise, in repeated sessions and in intervals ranging from 40 seconds to 10 minutes. The authors concluded that stretching had little or no effect on post-exercise soreness.

Another systematic review, by the Centers for Disease Control and Prevention, was published in the journal Medicine and Science in Sports and Exercise in 2004. It looked at multiple studies and found that stretching “was not significantly associated with a reduction in total injuries,” but also concluded that more research was needed.

For now, many experts say that what may work is a quick warm-up, like low-impact aerobics or walking. It also helps to ease into an activity by starting off slow and then increasing speed, intensity or weight (for lifting).


Research suggests that stretching does not affect soreness or risk of injury during exercise.

11. Low Diagnostic Yield of Electrocardiogram Testing in Younger Patients With Syncope

BC Sun, JR Hoffman, WR Mower, et al. Ann Emerg Med. 2008;51:240-246.

Although a number of published guidelines recommend ECG testing in patients with syncope, the diagnostic yield is low. This prospective study examined the frequency of ECG abnormalities in emergency department (ED) patients with syncope, whether abnormalities predict subsequent cardiac events, and whether either varies as a function of age. What this study adds to our knowledge: The ECG result was abnormal in a significant proportion of the 461 patients but did not reveal a cause of syncope in any of those younger than 40 years. How this might change clinical practice: If confirmed in larger studies, immediate ECG testing may not be necessary in many younger ED patients presenting with syncope.

Annals abstract:

12. Pioneering Research: Immunize (!) against Hypertension

A vaccine against angiotensin II lowers blood pressure, reports Lancet.

In a phase II (safety and efficacy) study sponsored by the developer, European researchers randomized 72 patients with mild-to-moderate hypertension to one of two doses of vaccine (100 or 300 μg) or to placebo. The vaccine consists of virus-like particles linked to angiotensin II; injections were given at weeks 0, 4, and 12.

By week 14, about 20% of vaccine recipients had experienced transient flu-like symptoms, and all had antibodies against angiotensin II. Those who received the 300-μg regimen had significant drops in mean BP compared with placebo recipients, especially early in the morning (–25 mm Hg systolic, –13 mm Hg diastolic).

Commentators wonder about the hazards of a treatment whose effects are not immediately reversible (the antibody's half-life after the third injection was 17 weeks). However, they find the exploratory trial "promising."

Lancet abstract:

13. New Out-of-Hospital CPR Protocol Increases Survival

A new CPR protocol, which focuses on compressions and not ventilatory support, increases the survival rate when used by emergency medical service personnel, JAMA reports.

The new protocol, called minimally interrupted cardiac resuscitation (MICR), consists of 200 compressions, followed by rhythm analysis with a single shock, another 200 compressions, a pulse check, and then rhythm reanalysis. Intubation is delayed until three rounds of compressions, and oxygenation until then is mostly passive.

Survival-to-discharge increased from 1.8% before MICR training to 5.4% afterwards. In cases of witnessed arrest and ventricular fibrillation, survival went from 4.7% to 17.6%.

An editorialist writes that although MICR "needs further scientific evaluation," such details "are likely not important factors to the numerous additional survivors who are back home with their families after the implementation of this new protocol."

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

14. Needle Thoracostomy: Size Does Matter

The standard 14-gauge needle and catheter are too short for 10% to 35% of patients.

Zengerink I, et al. J Trauma 2008;64:111-114.

Background: A tension pneumothorax requires immediate decompression using a needle thoracostomy. According to advanced trauma life support guidelines this procedure is performed in the second intercostal space (ICS) in the midclavicular line (MCL), using a 4.5-cm (2-inch) catheter (5-cm needle). Previous studies have shown a failure rate of up to 40% using this technique. Case reports have suggested that this high failure rate could be because of insufficient length of the needle.

Objectives: To analyze the average chest wall thickness (CWT) at the second ICS in the MCL in a trauma population and to evaluate the length of the needle used in needle thoracostomy for emergency decompression of tension pneumothoraces.

Methods: Retrospective review of major trauma admissions (Injury Severity Score greater than 12) at the Foothills Medical Centre in Calgary, Canada, who underwent a computed tomography chest scan admitted in the period from October 2001 until March 2004. Subgroup analysis on men and women, less than 40 years of age and greater than 40 years of age was defined a priori. CWT was measured to the nearest 0.01 cm at the second ICS in the MCL.

Results: The mean CWT in the 604 male patients and 170 female patients studied averaged 3.50 cm at the left second ICS MCL and 3.51 cm on the right. The mean CWT was significantly higher for women than men (p less than 0.0001). About 9.9% to 19.3% of the men had a CWT greater than 4.5 cm and 24.1% to 35.4% of the women studied.

Conclusions: A catheter length of 4.5 cm may not penetrate the chest wall of a substantial amount (9.9%-35.4%) of the population, depending on age and gender. This study demonstrates the need for a variable needle length for relief of a tension pneumothorax in certain population groups to improve effectiveness of needle thoracostomy.

15. Utility of Routine Testing for Patients with Asymptomatic Severe Blood Pressure Elevation in the ED

Karras DJ, at al. Ann Emerg Med. 2008;231-239.

Study objective
Recommendations for the treatment of emergency department (ED) patients with asymptomatic severely elevated blood pressure advise assessment for occult, acute hypertensive target-organ damage. This study determines the prevalence of unanticipated, clinically meaningful test abnormalities in ED patients with asymptomatic severely elevated blood pressure.

This was a prospective observational study at 3 urban academic EDs. Consecutive patients with systolic blood pressure greater than or equal to 180 mm Hg or diastolic blood pressure greater than or equal to 110 mm Hg on 2 measurements were enrolled if they denied symptoms of hypertensive emergency. A basic metabolic panel, urinalysis, ECG, CBC count, and chest radiograph were obtained. Treating physicians were interviewed about the indication for each test and whether an abnormal result was anticipated according to clinical findings. When test results were available, physicians were asked whether abnormal findings were clinically meaningful, defined as leading to unanticipated hospitalization, medication modification, or further immediate evaluation. The primary outcome was the prevalence of unanticipated clinically meaningful test abnormalities.

One hundred nine patients with asymptomatic severely elevated blood pressure were enrolled. Unanticipated abnormal test results were noted in 57 (52%) patients. Clinically meaningful unanticipated test abnormalities were found in 7 (6%) patients: basic metabolic panel in 2 (2%), CBC count in 3 (3%), urinalysis in 3 (4%), ECG in 2 (2%), and chest radiograph in 1 (1%). Five patients (5%) had abnormalities assessed as possible manifestations of acute hypertensive target-organ injury; none had abnormalities clearly related to severely elevated blood pressure.

Screening tests of urban ED patients with asymptomatic severely elevated blood pressure infrequently detect unanticipated hypertension-related abnormalities that alter ED management.

16. Doctors should be environmentalists too

Climate change is likely to be bad for human health. Drought, mass migration, food shortages, a surge in vector borne diseases, and deaths from extreme weather are just some of the possibilities, writes one surgeon from the US. Doctors and their institutions must do more to educate themselves about these very real threats and help to educate others. Medical schools could teach environmental science, specialist societies and research institutes could gather evidence on the likely effects of accelerating climate change on human health, hospitals could go green, and doctors could join forces with environmentalists to make plans and take action, he says.

The medical profession has a long history of responding to global challenges such as epidemics and natural disasters. It is time to step up and confront the state of the environment, along with the world’s governments, scientists, and businesses.

No one knows exactly what will happen, or how fast. But we do know that the ice caps are melting, the ozone layer is thinning, the planet is warming, and the world’s forests are being deliberately torched to grow crops to feed an exponentially increasing human population. All these events damage human health in one way or another, he says. Doctors must be part of the response.

Paul S. Auerbach, MD, MS. Physicians and the Environment. JAMA. 2008;299(8):956-958.

17. Limited Diagnostic Utility of Exam, History, and Labs in ED Patients with Vaginal Complaints

Johnson E, et al. Ann Emerg Med. 2008; print publication pending; published online 21 January 2008

This is a rational clinical examination abstract, a regular feature of the Annals' Evidence-Based Emergency Medicine (EBEM) series. Each features an abstract of a rational clinical examination review from the Journal of the American Medical Association and a commentary by an emergency physician knowledgeable in the subject area.

The source for this rational clinical examination review abstract is: Anderson MR, Klink K, Cohrssen A. The rational clinical examination: evaluation of vaginal complaints JAMA. 2004;291:1368-1379. The Annals' EBEM editors assisted in the preparation of the abstract of this rational clinical examination review, as well as selection of the Evidence-Based Medicine Teaching Points.

It appears that the clinical evaluation is limited in determining the cause of vaginal complaints. Several patient characteristics can support the diagnosis of vaginal candidiasis and bacterial vaginosis; however, the likelihood ratios are not particularly strong. Few findings distinguish bacterial vaginosis and vaginal trichomonas from each other, making these diagnoses even more difficult. Furthermore, bedside tests and laboratory equipment are not readily available in all clinical settings, leaving it up to the clinician to make a diagnosis solely based on medical history and physical examination results. Despite many studies on this topic, the competence of the clinical examination to determine the cause of vaginal complaints remains ill defined.

18. Rapid identification of high-risk transient ischemic attacks: prospective validation of the ABCD score.

Sciolla R, et al. Stroke. 2008; 39:297-302.

BACKGROUND AND PURPOSE: A 6-point score, based on age, blood pressure, clinical features, and duration (ABCD), was shown to effectively stratify the short-term risk of stroke after a transient ischemic attack (TIA). Prospective validation in different populations of patients should precede its widespread use. Whether adding computed tomography (CT) scan findings to the score would improve its performance deserves exploring. We aimed to validate the ABCD score in a prospective cohort of patients accessing Emergency Departments within 24 hours of a TIA in an area of northern Italy and to acquire preliminary data on CT-based refinement.

METHODS: During a 6-month period, all TIA patients accessing the Emergency Departments of 13 Piemonte and Valle d'Aosta hospitals were prospectively enrolled and stratified according to the 6-point ABCD score and to a 7-point score (ABCDI, where I=imaging) incorporating CT findings.

RESULTS: Of 274 patients, stroke occurred in 10 (3.6%) within 7 days and in 15 (5.5%) within 30 days. The ABCD score was predictive of stroke risk at both 7 and 30 days (odds ratio for every point of the score=2.55 at 7 days and 2.62 at 30 days; P for linear trend across the ABCD score levels=0.018 at 7 days and 0.0017 at 30 days). CT scan findings further increased prediction (odds ratio for every point of the score=2.68 at 7 days and 2.89 at 30 days; P for linear trend across the ABCDI score levels=0.0043 at 7 days and 0.0003 at 30 days).

CONCLUSIONS: The ABCD score confirmed its prognostic value in this prospective cohort. CT results could further improve prediction.

Review from 2005: ABCD Score May Aid Stroke Risk Stratification After TIA

This study is an important step toward identifying the patients who need urgent care after a TIA.

Using three cohorts of patients from Oxford, England, these authors sought to develop rules to predict the risk for stroke in the 7 days after diagnosis of transient ischemic attack (TIA). Other studies have identified risk factors for stroke after TIA, usually assessing longer periods. In the current study, the authors evaluated these same risk factors as potential short-term predictors in a total of 190 patients with TIA identified in the 1980s. From that analysis, they derived a stroke risk score, the ABCD score:

A (age; 1 point for age over 60 years),

B (blood pressure; 1 point for hypertension at the acute evaluation),

C (clinical features; 2 points for focal weakness, 1 for speech disturbance without weakness), and

D (symptom duration; 1 point for 10–59 minutes, 2 points for more than 60 minutes).

Total scores ranged from 0 (lowest risk) to 6 (highest risk).

In a validation cohort of 378 patients with more recent TIAs, 7-day stroke risk ranged from 0% in those with scores less than 4 to 35.5% in those with scores of 6; risk was intermediate with scores of 4 or 5. The ABCD worked surprisingly well, even in a third cohort of 206 patients from the same community who were scheduled to attend a weekly TIA clinic.

Comment: This study demonstrates once again that the risk for stroke in the first few days after TIA is very high. It confirms that simple clinical factors can be used to stratify that risk further. The score should be validated in a completely independent population before it gains widespread clinical use, and fine-tuning may be required, but this work represents an important step in understanding which patients with TIA require emergent evaluation.

— S. Claiborne Johnston, MD, PhD. Published in JW Neurology, September 8, 2005. Citation:
Rothwell PM et al. Lancet 2005 Jul 2; 366:29-36.

19. Tamiflu Label Updated with Neuropsychiatric Warning

The revised label adds a warning about possible neuropsychiatric side effects.

The FDA and Roche Laboratories have revised the product label for Tamiflu (oseltamivir phosphate) to include a warning about possible neuropsychiatric events. The updated label is based on recommendations from the agency’s Pediatric Advisory Committee meeting in November 2007.

Postmarketing reports indicate that some patients with influenza who were receiving Tamiflu had delirium and abnormal behavior, leading to injury and even death. Most of the cases occurred in children and in Japan.

Although it's not clear whether Tamiflu caused these events, the label cautions clinicians to monitor their patients for abnormal behavior when taking the drug. Adverse events should be reported through the FDA’s MedWatch site.

Published in Journal Watch Pediatrics and Adolescent Medicine March 12, 2008

20. Empirical Characteristics of Litigation Involving Tissue Plasminogen Activator and Ischemic Stroke

Liang BA, et al. Ann Emerg Med. 2008; print publication pending; published online 04 March 2008

Study objective
The use of tissue plasminogen activator (tPA) in potential stroke victims by emergency physicians is controversial. One factor that may represent a barrier to use is medicolegal concerns resulting from adverse outcomes. The jury verdicts, settlements, and other adjudications associated with tPA and stroke care are assessed to determine the characteristics of these cases, including whether cases arose from adverse consequences associated with tPA or failure to provide tPA.

Using 7 primary jury verdict, settlement, and other adjudication legal databases, lawsuits involving tPA and stroke were collected for analysis of the clinical circumstances of the litigation, the causes of action against providers, the basis for liability, and the presence of emergency physicians and neurologist consultation in the litigation.

Thirty-three cases were found involving tPA ischemic stroke therapy. In 29 (88%) of these cases, patient injury was claimed to have resulted from failure to treat with tPA. Emergency physicians were the most common physician defendants. Defendants prevailed in 21 (64%) cases, and among the 12 with results favorable to the plaintiff, 10 (83%) involved failure to treat and 2 (17%) claimed injury from treatment with tPA.

The available evidence concerning litigation involving stroke therapy with tPA indicates liability is predominantly associated with failure to provide tPA, rather than adverse events associated with its use.

21. Delayed Diagnosis of Kawasaki Disease: What Are the Risk Factors?

Minich LL, et al. Pediatrics 2007; 120:950 – 957.

OBJECTIVE. Because late diagnosis of Kawasaki disease increases the risk for coronary artery abnormalities, we explored the prevalence of and possible risk factors for delayed diagnosis by using the database of the Pediatric Heart Network trial of corticosteroid treatment for Kawasaki disease.

METHODS. We collected sociodemographic and clinical data at presentation for all patients who were treated for presumed Kawasaki disease at 8 centers (7 in the United States, 1 in Canada). Delayed diagnosis was evaluated by total number of illness days to diagnosis and by the percentage of patients who were treated after day 10 of illness. Independent predictors of delayed diagnosis were identified by using multivariate linear and logistic regression.

RESULTS. Of the 589 patients who received intravenous immunoglobulin, 27 were treated before screening for the trial and excluded; 562 patients formed the cohort for analysis. Kawasaki disease was diagnosed at 7.9 ± 3.9 days, 92 (16%) cases after day 10. Centers were similar with respect to patient age and gender. Centers differed in the patient percentage with incomplete Kawasaki disease; clinical criteria of cervical adenopathy, oral changes, and conjunctivitis; and distance of residence from the center. Independent predictors of greater number of illness days at diagnosis included center, age less than 6 months, incomplete Kawasaki disease, and greater distance from the center. Independent predictors of diagnosis after day 10 were age of less than 6 months, incomplete Kawasaki disease, and greater distance). Socioeconomic variables had no association with delayed diagnosis.

CONCLUSIONS. Even after adjustment for patient factors, illness duration at diagnosis varies by center. These findings underscore the need to maintain a high index of suspicion of Kawasaki disease in the infant who is younger than 6 months and has prolonged fever even with incomplete criteria. Outreach educational programs may be useful in promoting earlier recognition and treatment of Kawasaki disease.