Saturday, August 27, 2011

Lit Bits: August 27, 2011

From the recent medical literature...

1. Malpractice Risk According to Physician Specialty

Jena AB, et al. N Engl J Med 2011;365:629-636.

Background: Data are lacking on the proportion of physicians who face malpractice claims in a year, the size of those claims, and the cumulative career malpractice risk according to specialty.

Methods: We analyzed malpractice data from 1991 through 2005 for all physicians who were covered by a large professional liability insurer with a nationwide client base (40,916 physicians and 233,738 physician-years of coverage). For 25 specialties, we reported the proportion of physicians who had malpractice claims in a year, the proportion of claims leading to an indemnity payment (compensation paid to a plaintiff), and the size of indemnity payments. We estimated the cumulative risk of ever being sued among physicians in high- and low-risk specialties.

Results: Each year during the study period, 7.4% of all physicians had a malpractice claim, with 1.6% having a claim leading to a payment (i.e., 78% of all claims did not result in payments to claimants). The proportion of physicians facing a claim each year ranged from 19.1% in neurosurgery, 18.9% in thoracic–cardiovascular surgery, and 15.3% in general surgery to 5.2% in family medicine, 3.1% in pediatrics, and 2.6% in psychiatry. The mean indemnity payment was $274,887, and the median was $111,749. Mean payments ranged from $117,832 for dermatology to $520,923 for pediatrics. It was estimated that by the age of 65 years, 75% of physicians in low-risk specialties had faced a malpractice claim, as compared with 99% of physicians in high-risk specialties.

Conclusions: There is substantial variation in the likelihood of malpractice suits and the size of indemnity payments across specialties. The cumulative risk of facing a malpractice claim is high in all specialties, although most claims do not lead to payments to plaintiffs. (Funded by the RAND Institute for Civil Justice and the National Institute on Aging.)

Full-text (free): http://www.nejm.org/doi/full/10.1056/NEJMsa1012370#t=articleTop

2. The pulmonary embolism rule-out criteria (PERC) rule does not safely exclude pulmonary embolism.

Hugli O, et al. J Thromb Haemost. 2011;9:300-4.

BACKGROUND: The Pulmonary Embolism Rule-out Criteria (PERC) rule is a clinical diagnostic rule designed to exclude pulmonary embolism (PE) without further testing. We sought to externally validate the diagnostic performance of the PERC rule alone and combined with clinical probability assessment based on the revised Geneva score.

METHODS: The PERC rule was applied retrospectively to consecutive patients who presented with a clinical suspicion of PE to six emergency departments, and who were enrolled in a randomized trial of PE diagnosis. Patients who met all eight PERC criteria [PERC((-))] were considered to be at a very low risk for PE. We calculated the prevalence of PE among PERC((-)) patients according to their clinical pretest probability of PE. We estimated the negative likelihood ratio of the PERC rule to predict PE.

RESULTS: Among 1675 patients, the prevalence of PE was 21.3%. Overall, 13.2% of patients were PERC((-)). The prevalence of PE was 5.4% [95% confidence interval (CI): 3.1-9.3%] among PERC((-)) patients overall and 6.4% (95% CI: 3.7-10.8%) among those PERC((-)) patients with a low clinical pretest probability of PE. The PERC rule had a negative likelihood ratio of 0.70 (95% CI: 0.67-0.73) for predicting PE overall, and 0.63 (95% CI: 0.38-1.06) in low-risk patients.

CONCLUSIONS: Our results suggest that the PERC rule alone or even when combined with the revised Geneva score cannot safely identify very low risk patients in whom PE can be ruled out without additional testing, at least in populations with a relatively high prevalence of PE.

3. New Options in Anticoagulation for Atrial Fibrillation

del Zoppo GJ, et al. N Engl J Med 2011; Aug 10. [Epub ahead of print]

The presence of atrial fibrillation significantly increases the risk and burden of thromboembolic stroke.1 Warfarin is the reference standard treatment for the primary prevention of embolic stroke during atrial fibrillation.2 However, the long-term use of warfarin has its limitations. Although guidelines suggest a target international normalized ratio (INR) of 2.5 (range, 2.0 to 3.0) for this indication,2 only about 60% of patients have an INR within the recommended range at a given time in usual clinical practice. This is the reason that is most often given for the search for other oral antithrombotic agents that could be simpler to manage and that might replace warfarin in such patients.

Two recent studies have compared new antithrombotic agents with warfarin for the primary prevention of thromboembolic events in patients with nonvalvular atrial fibrillation. In this issue of the Journal, Patel et al.3 report the results of the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF), in which the investigators compared rivaroxaban, a direct factor Xa inhibitor, with warfarin. This study follows on the heels of the report of the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial (ClinicalTrials.gov number, NCT00262600),4 showing that dabigatran, a direct thrombin inhibitor, was not inferior to warfarin. Both studies provide some points to ponder for a condition in which placebo-controlled trials are no longer possible.

One interesting point is how the interpretation of ROCKET AF depends on the results from the three different protocol-specified analyses of the primary outcome of stroke or systemic embolism. The primary analysis included only patients who were treated according to protocol and were followed for outcome events only for the period during which they were actually receiving the assigned treatment (or within 2 days after the last dose). This analysis, designated the “per-protocol, as-treated” analysis, resulted in a conservative test for noninferiority5 and showed that rivaroxaban was significantly noninferior to warfarin. The authors also tested for superiority using an intention-to-treat analysis, which did not show superiority for rivaroxaban over warfarin.

Between these two analyses, the authors conducted another analysis in the “as-treated safety population.” Here, they included all patients who received at least one dose of a study drug and were followed for events while receiving the drug (or within 2 days after the last dose), regardless of adherence to protocol. It is not surprising that the annual event rates in the two study groups in this analysis were much closer to those of the per-protocol analysis than to those in the intention-to-treat analysis. As a consequence, in the safety analysis, the between-group P value was significant, even though the results do not show superiority for rivaroxaban over warfarin, since the intention-to-treat analysis was negative. Thus, the multiple analyses have muddied the waters regarding rivaroxaban's efficacy and effectiveness over warfarin.

Trials comparing new oral antithrombotic agents with warfarin are dependent on the quality of the management of the warfarin cohort. Overall compliance varies. Trials like ROCKET AF and RE-LY use algorithms for imputing the dummy INR of the warfarin placebo in patients who are not receiving warfarin in order to maintain blinding. They also use the concept of “time in therapeutic range” to assess the quality of warfarin management. Such trials typically use a method described by Rosendaal et al.,6 in which the measured INR values and the interval between INR tests are both taken into account. On the basis of this approach, INR values were within the therapeutic range a mean of 55% of the time in ROCKET AF and 64% in the RE-LY trial. So the interpretation of noninferiority in a given trial may also depend both on the homogeneity and treatment accuracy of the warfarin cohort and on the dummy INR algorithm that is used.

Overall, the frequency of major hemorrhagic events in ROCKET AF did not differ significantly between the rivaroxaban group and the warfarin group. A similar finding was seen in the RE-LY study. However, interestingly, both studies showed a reduction in the rate of intracranial hemorrhage with the new oral antithrombotic agent, as compared with warfarin. The reasons for the potential reduction in intracranial hemorrhage that was associated with these agents are not clear, but one possibility is the effect on a single target in the hemostatic system by the new antithrombotic agents versus the multiple targets by warfarin.7 More intriguing is the possibility that cerebral vascular beds have protective features that are more apparent at the doses of either of the new agents tested. The presence of large amounts of tissue factor in the cerebral vascular neighborhood could modulate vascular hemostatic activity within brain vessels. It is possible that neither rivaroxaban nor dabigatran affects the complex made up of tissue factor and factor VIIa, whereas warfarin decreases factor VII activity. Does this difference influence the risk of hemorrhage? Fundamental studies of cerebral vascular responses to these agents and of the differential risk of intracranial hemorrhage in the two trials would be instructive.

For the management of atrial fibrillation, oral alternatives to warfarin have arrived. Their simplicity of use is attractive, and they appear to have an efficacy similar to that of warfarin, with the proviso that comparisons seem to depend on how easily the patient can be treated with warfarin. An important concern that these clinical trials do not address is the absence of antidotes to rapidly reverse the anticoagulant effects of either rivaroxaban or dabigatran in the case of life-threatening hemorrhage or surgery. All these issues need to be taken into account in clinical decision making. Further studies will be necessary to refine the treatment of a growing population of patients with atrial fibrillation in order to reduce the risk of stroke.

References: http://www.nejm.org/doi/full/10.1056/NEJMe1107516

4. ECG Findings in ED Patients with Syncope

Quinn J, et al. Acad Emerg Med. 2011; 18:714–718

Objectives: To determine the sensitivity and specificity of the San Francisco Syncope Rule (SFSR) electrocardiogram (ECG) criteria for determining cardiac outcomes and to define the specific ECG findings that are the most important in patients with syncope.

Methods: A consecutive cohort of emergency department (ED) patients with syncope or near syncope was considered. The treating emergency physicians assessed 50 predictor variables, including an ECG and rhythm assessment. For the ECG assessment, the physicians were asked to categorize the ECG as normal or abnormal based on any changes that were old or new. They also did a separate rhythm assessment and could use any of the ECGs or available monitoring strips, including prehospital strips, when making this assessment. All patients were followed up to determine a broad composite study outcome. The final ECG criterion for the SFSR was any nonsinus rhythm or new ECG changes. In this specific study, the initial assessments in the database were used to determine only cardiac-related outcomes (arrhythmia, myocardial infarction, structural, sudden death) based on set criteria, and the authors determined the sensitivity and specificity of the ECG criteria for cardiac outcomes only. All ECGs classified as “abnormal” by the study criteria were compared to the official cardiology reading to determine specific findings on the ECG. Univariate and multivariate analysis were used to determine important specific ECG and rhythm findings.

Results: A total of 684 consecutive patients were considered, with 218 having positive ECG criteria and 42 (6%) having important cardiac outcomes. ECG criteria predicted 36 of 42 patients with cardiac outcomes, with a sensitivity of 86% (95% confidence interval [CI] = 71% to 94%), a specificity of 70% (95% CI = 66% to 74%), and a negative predictive value of 99% (95% CI = 97% to 99%). Regarding specific ECG findings, any nonsinus rhythm from any source and any left bundle conduction problem (i.e., any left bundle branch block, left anterior fascicular block, left posterior fascicular block, or QRS widening) were 2.5 and 3.5 times more likely associated with significant cardiac outcomes.

Conclusions: The ECG criteria from the SFSR are relatively simple, and if used correctly can help predict which patients are at risk of cardiac outcomes. Furthermore, any left bundle branch block conduction problems or any nonsinus rhythms found during the ED stay should be especially concerning for physicians caring for patients presenting with syncope.

The SF Syncope Rule: http://www.mdcalc.com/san-francisco-syncope-rule-to-predict-serious-outcomes

Related syncope abstract on the ROSE Decision Instrument in Ann Emerg Med Sept 2011: http://www.annemergmed.com/article/S0196-0644(10)01931-1/abstract

5. Cycling is good for you—even in the big city

The health risks and benefits of cycling in urban environments compared with car use: health impact assessment study

Rojas-Rueda D, et al. BMJ 2011;343:d4521

Objective: To estimate the risks and benefits to health of travel by bicycle, using a bicycle sharing scheme, compared with travel by car in an urban environment.

Design: Health impact assessment study.

Setting: Public bicycle sharing initiative, Bicing, in Barcelona, Spain.

Participants: 181 982 Bicing subscribers.

Main outcomes measures: The primary outcome measure was all cause mortality for the three domains of physical activity, air pollution (exposure to particulate matter smaller than 2.5 µm), and road traffic incidents. The secondary outcome was change in levels of carbon dioxide emissions.

Results: Compared with car users the estimated annual change in mortality of the Barcelona residents using Bicing (n=181 982) was 0.03 deaths from road traffic incidents and 0.13 deaths from air pollution. As a result of physical activity, 12.46 deaths were avoided (benefit:risk ratio 77). The annual number of deaths avoided was 12.28. As a result of journeys by Bicing, annual carbon dioxide emissions were reduced by an estimated 9 062 344 kg.

Conclusions: Public bicycle sharing initiatives such as Bicing in Barcelona have greater benefits than risks to health and reduce carbon dioxide emissions.

6. Low Prevalence of Bacteremia in Children with Community Acquired Pneumonia

Shah SS et al. Pediatr Infect Dis J 2011;30:475

Blood culture results rarely changed management, and did so mainly in children with complicated CAP.

Background: Blood cultures are frequently obtained in the emergency department (ED) evaluation of children with community-acquired pneumonia (CAP).

Objectives: To determine the prevalence of bacteremia in children presenting to the ED with CAP, identify subgroups at increased risk for bacteremia, and quantify the effect of positive blood cultures on management.

Methods: This case–control study was nested within a cohort of children followed up at 35 pediatric practices. Patients from this cohort who were ≤18 years of age, evaluated in the ED in 2006–2007, and diagnosed with CAP were eligible. Cases were those with bacteremia. Controls included those with negative blood cultures and those without blood cultures performed.

Results: A total of 877 (9.6%) of 9099 children with CAP were evaluated in the ED. The mean age was 3.6 years; 53% were male. Blood cultures were obtained from 291 children (33.2%). Overall, the prevalence of bacteremia was 2.1% (95% confidence interval [CI]: 0.8%–4.4%). Bacteremia occurred in 2.6% (95% CI: 1.0%–5.6%) with an infiltrate on chest radiograph and in 13.0% (95% CI: 2.8%–33.6%) with complicated pneumonia. Streptococcus pneumoniae accounted for 4 of the 6 cases of bacteremia. Blood culture results altered management in 5 of the 6 bacteremic patients; 1 had an appropriate broadening and 4 had an appropriate narrowing of coverage. The contamination rate was 1.0% (95% CI: 0.2%–3.0%).

Conclusion: Children presenting to the ED for evaluation of CAP are at low-risk for bacteremia. Although positive blood cultures frequently altered clinical management, the overall impact was small because of the low prevalence of bacteremia..

7. Diagnosis of Spinal Cord Compression in Nontrauma Patients in the ED

Dugas AF, et al. Acad Emerg Med. 2011;18:719–725

Objectives:  The objectives were to evaluate the presenting signs and symptoms of spinal cord and cauda equina compression (SCC) and to determine the incidence of emergency department (ED) misdiagnosis.

Methods:  This was a retrospective chart review at an urban, tertiary care hospital of patients discharged from an inpatient stay (April 2008 through July 2009) with an International Classification of Diseases, Ninth Revision (ICD-9) code indicating spinal disease, who had visited the ED for a related complaint within the previous 30 days, and who had a final diagnosis of new SCC. Trauma and transferred patients were excluded. The authors defined a misdiagnosis as no ED-documented diagnosis of SCC and failure to perform an appropriate diagnostic study either prior to arrival, in the ED, or immediately upon admission.

Results:  Of 1,231 charts reviewed, 63 met inclusion criteria. The most common presenting symptoms in patients with SCC were pain (44, 70%), difficulty ambulating (38, 60%), and weakness (35, 56%). On physical examination, motor deficits (45, 71%) were more common than sensory deficits (27, 43%); however, 15 (24%) patients had no motor or sensory deficit, and 13 (23%) patients only had unilateral findings. Impaired gait was present in 14 patients of only 20 tested, three of whom had no associated motor or sensory deficit. SCC was misdiagnosed in 18 (29%, 95% confidence interval [CI] = 19% to 41%) cases, which resulted in a significant delay to diagnosis (median = 54 hours, interquartile range [IQR] = 38 to 77 vs. 5.3 hours, IQR = 3.0 to 15) in these patients.

Conclusions:  SCC can have a subtle presentation with absent or unilateral motor and sensory deficits, but gait ataxia may be an additional finding. ED misdiagnosis of SCC in nontrauma patients is common.

8. Intraosseous Versus Intravenous Vascular Access during Out-of-Hospital Cardiac Arrest: A Randomized Controlled Trial

Reades R, et al. Ann Emerg Med. 2011; in press

Study objective: Intraosseous needle insertion during out-of-hospital cardiac arrest is rapidly replacing peripheral intravenous routes in the out-of-hospital setting. However, there are few data directly comparing the effectiveness of intraosseous needle insertions with peripheral intravenous insertions during out-of-hospital cardiac arrest. The objective of this study is to determine whether there is a difference in the frequency of first-attempt success between humeral intraosseous, tibial intraosseous, and peripheral intravenous insertions during out-of-hospital cardiac arrest.

Methods: This was a randomized trial of adult patients experiencing a nontraumatic out-of-hospital cardiac arrest in which resuscitation efforts were initiated. Patients were randomized to one of 3 routes of vascular access: tibial intraosseous, humeral intraosseous, or peripheral intravenous. Paramedics received intensive training and exposure to all 3 methods before study initiation. The primary outcome was first-attempt success, defined as secure needle position in the marrow cavity or a peripheral vein, with normal fluid flow. Needle dislodgement during resuscitation was coded as a failure to maintain vascular access.

Results: There were 182 patients enrolled, with 64 (35%) assigned to tibial intraosseous, 51 (28%) humeral intraosseous, and 67 (37%) peripheral intravenous access. Demographic characteristics were similar among patients in the 3 study arms. There were 130 (71%) patients who experienced initial vascular access success, with 17 (9%) needles becoming dislodged, for an overall frequency of first-attempt success of 113 (62%). Individuals randomized to tibial intraosseous access were more likely to experience a successful first attempt at vascular access (91%; 95% confidence interval [CI] 83% to 98%) compared with either humeral intraosseous access (51%; 95% CI 37% to 65%) or peripheral intravenous access (43%; 95% CI 31% to 55%) groups. Time to initial success was significantly shorter for individuals assigned to the tibial intraosseous access group (4.6 minutes; interquartile range 3.6 to 6.2 minutes) compared with those assigned to the humeral intraosseous access group (7.0 minutes; interquartile range 3.9 to 10.0 minutes), and neither time was significantly different from that of the peripheral intravenous access group (5.8 minutes; interquartile range 4.1 to 8.0 minutes).

Conclusion: Tibial intraosseous access was found to have the highest first-attempt success for vascular access and the most rapid time to vascular access during out-of-hospital cardiac arrest compared with peripheral intravenous and humeral intraosseous access

9. Placebo by Proxy: Effects on the Patient’s Friends and Family

Grelotti DJ, et al. BMJ 2011;343:d4345

Clinicians’ and family members’ feelings and perceptions about a treatment may influence their judgments about its effectiveness

The effect of placebo on the patient and the patient’s environment is often debated, but people other than the patient may also feel better when a patient receives placebo treatment. The anthropologist Claude Lévi-Strauss alluded to this when he described how medical treatments, including those where ritual alone provides the cure, occur in a social context and convey a “sense of security” to the social group.1

Clinicians and family members may have an emotional response to a patient’s treatment and think that the treatment is helping the patient even in the absence of any direct physiological benefit to the patient or indication from the patient that the treatment is working. These feelings and perceptions may arise when placebos, including “impure” placebos, such as active drugs or operations that have no effect on the disease process, are used in clinical practice and research settings. Because these feelings and perceptions are not accounted for in descriptions of the placebo effect and can exist independently of any placebo effect on the patient, they can be described as placebo effects by proxy, or placebo by proxy for short. Although placebo by proxy has important implications, the phenomenon is underappreciated and rarely discussed.

Placebo by proxy could be as ubiquitous as the placebo effect, and in some situations placebo by proxy can dominate clinical decision making. For example, the parents of a child with a viral upper respiratory illness may believe that the child needs antibiotics, and parental expectations or the doctor’s perception of parental expectations (or both) may influence prescribing patterns.2 3 Antibiotics are overprescribed in these situations and function as impure placebos4; the psychological benefit to the parent, such as a relief from worry, represents placebo by proxy.

In the absence of evidence to support long term use of antipsychotics in patients with dementia and a history of agitation, aggression, or psychosis,5 6placebo by proxy may help to explain why clinicians often maintain their patients on these drugs. In a controlled double blind study of discontinuation of psychotropics in a sample of patients with dementia who were taking these drugs because of a history of agitation (67.3% were taking antipsychotics), the authors found a lack of an effect of psychotropics when they compared mean scores on behaviour rating scales during the treatment and placebo phases of the trial.6 However, clinical workers were resistant to stopping treatment because they had “a great deal of faith in the utility of these drugs to control agitation in this population.”6 Psychotropics functioned as impure placebos for many of these patients, and the concern of clinicians that patients would decompensate without these drugs provides another example of placebo by proxy.

In addition to influencing clinical decision making, placebo by proxy could influence estimations of treatment outcome in trials, especially when the perceptions of clinicians or family members are favoured over objective markers of patient response.7 In placebo controlled clinical trials of secretin to reduce symptoms of autism, the patient’s response to secretin was primarily based on the opinions of parents, teachers, or clinicians (or a combination thereof).8 Ten randomised controlled trials and a meta-analysis showed robust and consistent reductions in core symptoms of autism as measured by standardised rating scales in both the treatment and placebo groups, but no significant differences were seen between the groups on these measures.8 9 The robust response to placebo may have been influenced by anecdotal reports, which generated positive press about secretin and gave rise to the need for clinical trials.8 9 Perception or misperception by parents may also partially explain a larger placebo response in children than in adults participating in clinical trials of treatment resistant epilepsy.10

Placebo by proxy may also explain findings from meta-analyses where improvement measured by observers is much higher than improvement reported by patients. For example, for depression, the mean effect size of observer rated improvement is 1.85 (95% confidence interval 1.69 to 2.01), compared with 0.67 (0.49 to 0.85) for patient reported improvement.11 For irritable bowel syndrome, the pooled placebo response rate for physician rated improvement is 53.0%, compared with 37.4% for patient rated improvement (P=0.005).12

The different mechanisms that underlie the placebo effect are likely to shape placebo by proxy also.12 These processes may include seeing other patients respond to the same drug, associative learning such as conditioning, a supportive physician-patient relationship, and reduced anxiety.

Placebo by proxy and the placebo effect may interact to create positive change. For example, if clinicians and family members feel empowered and optimistic about a disease, the patient’s environment can become less stressful and more supportive. Clinicians and family members may react to placebo by smiling more, paying more attention to the patient, promoting treatment adherence, encouraging the patient to engage in new activities, or creating other targets for behavioural change.8 9 In this way, placebo by proxy may elicit changes in the patient’s psychosocial context that mediate the placebo effect.

Although placebo by proxy may enhance clinical outcomes, it might also cause harm. If treatment related decisions are unduly weighted towards providing a psychological benefit to people other than the patient, the patient may not benefit from the treatment yet may still bear the risks. The treatments mentioned above cost money and are not benign: antibiotics cause diarrhoea and are associated with antibiotic resistance, antipsychotics are associated with an increased risk of death in elderly patients with dementia related psychosis, and secretin infusion may result in a life threatening allergic reaction. Placebo by proxy may create a false sense that a patient is getting better and thereby prevent more appropriate treatment,7 8 or it may produce changes in attitude and behaviour towards the patient that lead to neglect. Placebo by proxy is probably more likely to cause harm when decisions are made in the absence of clinical evidence and when patients cannot make decisions for themselves.

Treatment benefits could be maximised and harms mitigated if placebo by proxy were taken into account when making clinical decisions. For many of the above clinical situations, an appreciation of placebo by proxy may prompt clinicians to question attachments to treatment practices that are not supported by evidence. Placebo by proxy could be used as a potential clinical tool. For example, it may be possible to boost the psychological benefit of a patient’s treatment by generating appropriate enthusiasm for treatment among those involved in the patient’s care. Because almost every treatment related decision is shared and patients sometimes agree to treatment to make their clinicians and family members happy, clinicians should be aware of placebo by proxy when guiding clinical decisions and evaluating treatment response.

10. Evidence-based Diagnostics: Adult Septic Arthritis

Carpenter CR, et al. Acad Emerg Med. 2011;18:782-796.

Background:  Acutely swollen or painful joints are common complaints in the emergency department (ED). Septic arthritis in adults is a challenging diagnosis, but prompt differentiation of a bacterial etiology is crucial to minimize morbidity and mortality.

Objectives:  The objective was to perform a systematic review describing the diagnostic characteristics of history, physical examination, and bedside laboratory tests for nongonococcal septic arthritis. A secondary objective was to quantify test and treatment thresholds using derived estimates of sensitivity and specificity, as well as best-evidence diagnostic and treatment risks and anticipated benefits from appropriate therapy.

Methods:  Two electronic search engines (PUBMED and EMBASE) were used in conjunction with a selected bibliography and scientific abstract hand search. Inclusion criteria included adult trials of patients presenting with monoarticular complaints if they reported sufficient detail to reconstruct partial or complete 2 × 2 contingency tables for experimental diagnostic test characteristics using an acceptable criterion standard. Evidence was rated by two investigators using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS). When more than one similarly designed trial existed for a diagnostic test, meta-analysis was conducted using a random effects model. Interval likelihood ratios (LRs) were computed when possible. To illustrate one method to quantify theoretical points in the probability of disease whereby clinicians might cease testing altogether and either withhold treatment (test threshold) or initiate definitive therapy in lieu of further diagnostics (treatment threshold), an interactive spreadsheet was designed and sample calculations were provided based on research estimates of diagnostic accuracy, diagnostic risk, and therapeutic risk/benefits.

Results:  The prevalence of nongonococcal septic arthritis in ED patients with a single acutely painful joint is approximately 27% (95% confidence interval [CI] = 17% to 38%). With the exception of joint surgery (positive likelihood ratio [+LR] = 6.9) or skin infection overlying a prosthetic joint (+LR = 15.0), history, physical examination, and serum tests do not significantly alter posttest probability. Serum inflammatory markers such as white blood cell (WBC) counts, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) are not useful acutely. The interval LR for synovial white blood cell (sWBC) counts of 0 × 109–25 × 109/L was 0.33; for 25 × 109–50 × 109/L, 1.06; for 50 × 109–100 × 109/L, 3.59; and exceeding 100 × 109/L, infinity. Synovial lactate may be useful to rule in or rule out the diagnosis of septic arthritis with a +LR ranging from 2.4 to infinity, and negative likelihood ratio (–LR) ranging from 0 to 0.46. Rapid polymerase chain reaction (PCR) of synovial fluid may identify the causative organism within 3 hours. Based on 56% sensitivity and 90% specificity for sWBC counts above 50 × 109/L in conjunction with best-evidence estimates for diagnosis-related risk and treatment-related risk/benefit, the arthrocentesis test threshold is 5%, with a treatment threshold of 39%.

Conclusions:  Recent joint surgery or cellulitis overlying a prosthetic hip or knee were the only findings on history or physical examination that significantly alter the probability of nongonococcal septic arthritis. Extreme values of sWBC (above 50 × 109/L) can increase, but not decrease, the probability of septic arthritis. Future ED-based diagnostic trials are needed to evaluate the role of clinical gestalt and the efficacy of nontraditional synovial markers such as lactate.

11. Performance of 4 clinical decision rules in the diagnostic management of acute pulmonary embolism: a prospective cohort study

Douma RA, et al. Ann Intern Med. 2011;154(11):709-18.

BACKGROUND: Several clinical decision rules (CDRs) are available to exclude acute pulmonary embolism (PE), but they have not been directly compared.

OBJECTIVE: To directly compare the performance of 4 CDRs (Wells rule, revised Geneva score, simplified Wells rule, and simplified revised Geneva score) in combination with d-dimer testing to exclude PE.

DESIGN: Prospective cohort study.

SETTING: 7 hospitals in the Netherlands.

PATIENTS: 807 consecutive patients with suspected acute PE.

INTERVENTION: The clinical probability of PE was assessed by using a computer program that calculated all CDRs and indicated the next diagnostic step. Results of the CDRs and d-dimer tests guided clinical care.

MEASUREMENTS: Results of the CDRs were compared with the prevalence of PE identified by computed tomography or venous thromboembolism at 3-month follow-up.

RESULTS: Prevalence of PE was 23%. The proportion of patients categorized as PE-unlikely ranged from 62% (simplified Wells rule) to 72% (Wells rule). Combined with a normal d-dimer result, the CDRs excluded PE in 22% to 24% of patients. The total failure rates of the CDR and d-dimer combinations were similar (1 failure, 0.5% to 0.6% [upper-limit 95% CI, 2.9% to 3.1%]). Even though 30% of patients had discordant CDR outcomes, PE was not detected in any patient with discordant CDRs and a normal d-dimer result.

LIMITATION: Management was based on a combination of decision rules and d-dimer testing rather than only 1 CDR combined with d-dimer testing.

CONCLUSION: All 4 CDRs show similar performance for exclusion of acute PE in combination with a normal d-dimer result. This prospective validation indicates that the simplified scores may be used in clinical practice.

12. Three Evidence Based Summaries

A. Does Therapeutic Hypothermia Benefit Survivors of Cardiac Arrest?

Seupaul RA, et al. Ann Emerg Med 2011;58:282-283

Take Home Message: Therapeutic hypothermia with conventional cooling methods improves survival and neurologic outcomes at hospital discharge for patients who have experienced a cardiac arrest.

Full text (free): http://www.annemergmed.com/article/S0196-0644(11)00115-6/fulltext

B. Do Triptans Effectively Treat Acute Cluster Headache in the Emergency Department?

Seupaul RA, et al. Ann Emerg Med 2011;58:284-285

Take Home Message: Triptans, particularly if administered subcutaneously, provide rapid relief for acute cluster headache.

Full text (free): http://www.annemergmed.com/article/S0196-0644(11)00126-0/fulltext

C. Is the Canalith Repositioning Maneuver Effective in the Acute Management of Benign Positional Vertigo?

Brown MD. Ann Emerg Med 2011;58:286-287

Take Home Message: The Epley maneuver is a very effective treatment for benign paroxysmal positional vertigo.

Full text (free): http://www.annemergmed.com/article/S0196-0644(11)00139-9/fulltext

13. Diagnostic Accuracy of High-Sensitivity Troponin Assays at 2 Hours

The high negative predictive value provides one more stone in the road to a 2-hour rule-out protocol for AMI.

New high-sensitivity troponin (hs-Tn) assays can detect minute amounts of troponin, potentially allowing earlier definitive diagnosis of acute myocardial infarction (AMI) than is currently possible (JW Emerg Med Apr 16 2010). In a prospective observational international study, researchers compared the diagnostic accuracy of absolute and relative changes in troponin I and T levels measured with hs-Tn assays in 1197 consecutive patients who presented to emergency departments with symptoms suggesting AMI and without ST-segment elevation on the initial electrocardiogram. Usual care was provided. The final diagnosis of AMI was determined by independent cardiologists who were blinded to the hs-Tn assay results.

Blood samples drawn at presentation and at 1, 2, 3, and 6 hours were available for 590 patients. AMI was the final diagnosis in 108 patients (13%). Absolute changes in troponin levels performed significantly better than relative changes on all performance measures. The absolute change in troponin T within 2 hours had a sensitivity of 89%, specificity of 93%, positive predictive value of 64%, and negative predictive value of 98% for AMI; results were similar for troponin I. Absolute changes at 6 hours (available for 305 patients) did not improve on the accuracy of those at 2 hours.

Comment: This was a study of chemical measurements, not of clinical care, which proceeded in the usual fashion; thus, the findings should not change practice. The study does, however, offer the prospect of changes to guidelines, which could speed throughput and allow more rapid determination of the need for interventional cardiology measures.

— J. Stephen Bohan, MD, MS, FACP, FACEP. Published in Journal Watch Emergency Medicine August 12, 2011. Citation: Reichlin T et al. Utility of absolute and relative changes in cardiac troponin concentrations in the early diagnosis of acute myocardial infarction. Circulation 2011 Jul 12; 124:136.

14. Neuron overload and the juggling physician

Danielle Ofri. The Lancet. 2010; 376:1820 – 1821.

Patients often complain that their doctors don't listen. Although there are probably a few doctors who truly are tone deaf, most are reasonably empathic human beings, and I wonder why even these doctors seem prey to this criticism. I often wonder whether it is sheer neuron overload on the doctor side that leads to this problem. Sometimes it feels as though my brain is juggling so many competing details, that one stray request from a patient—even one that is quite relevant—might send the delicately balanced three-ring circus tumbling down.

…Studies have debunked the myth of multitasking in human beings. The concept of multitasking was developed in the computer field to explain the idea of a microprocessor doing two jobs at one time. It turns out that microprocessors are in fact linear, and actually perform only one task at a time. Our computers give the illusion of simultaneous action based on the microprocessor “scheduling” competing activities in a complicated integrated algorithm. Like microprocessors, we humans can't actually concentrate on two thoughts at the same exact time. We merely zip back and forth between them, generally losing accuracy in the process. At best, we can juggle only a handful of thoughts in this manner.

The more thoughts we juggle, the less we are able to attune fully to any given thought. To me, this is a recipe for disaster. Today I only forgot an insurance company form. But what if I'd forgotten to order her mammogram, or what if I'd refilled only five of her six medicines? What if I'd forgotten to fully explain the side-effects of one of her medications? The list goes on, as does the anxiety.

The remainder of the essay (full-text free): http://danielleofri.com/wp-content/uploads/2010/11/Neuron-Overload-Ofri.pdf

15. Vasopressin During Resuscitation May Help Asystolic Patients

NEW YORK (Reuters Health) Aug 09 - Vasopressin has no overall benefit in cardiac arrest, but it may be useful in asystole - especially when administered promptly, according to a meta-analysis reported July 25 in Resuscitation.

"The novel finding... was that in the large asystole subgroup (n=3,210), vasopressin use was associated with an increased probability of long-term survival," the authors report.

They said the absolute increase was about 1.0%, corresponding to 10 additional survivors for every 1,000 treated patients.

Furthermore, the vasopressin-related survival benefit was quadrupled in the 642 asystole patients whose average time-to-drug was under 20 minutes. That subgroup had an absolute increase of 4.0%, corresponding to 40 additional survivors for every 1,000 treated patients.

Dr. Spyros D. Mentzelopoulos, with Evaggelismos General Hospital in Athens, Greece, and colleagues say they undertook the study because there had been new trial data reported since the last review in 2004, and also because there was a possibility of increased vasoconstricting efficacy of current vasopressin regimens during CPR.

The team identified six high-quality randomized controlled trials comparing vasopressin-containing regimens with adrenaline/epinephrine alone in 4,475 adults with cardiac arrest.

Overall, vasopressin didn't increase the chance of sustained return of spontaneous circulation (odds ratio 1.25; p=0.18), long-term survival (OR 1.13; p=0.61) or favorable neurologic outcome (OR 0.87; p=0.62), the report indicates.

However, when the initial cardiac rhythm was identified as asystole (as opposed to pulseless electrical activity or ventricular fibrillation or tachycardia), vasopressin use was associated with a higher likelihood of long-term survival (OR 1.80; p=0.04). Moreover, in asystolic patients treated within 20 minutes of collapse, the odds ratio increased to 2.84 (p=0.02), Dr. Mentzelopoulos and colleagues found.

They conclude, "New randomized controlled trials specifically assessing vasopressin effects on subgroup neurological outcome are warranted."

Resuscitation 2011. In press. Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21787738

16. Images in Medicine

Fixed Drug Eruption
http://www.nejm.org/doi/full/10.1056/NEJMicm1013871

An Unusual Cause of Trigger Finger
http://www.nejm.org/doi/full/10.1056/NEJMicm1012468

“Thumb Sign” of Epiglottitis
http://www.nejm.org/doi/full/10.1056/NEJMicm1009990

Hemorrhagic Herpes Zoster
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)60238-9/fulltext

Bed Bugs
http://www.scielo.br/img/revistas/abd/v86n1/en_a28fig01m.jpg

*More on Bed Bugs*
Case presentation: http://www.ncbi.nlm.nih.gov/pubmed/21437544 (with link to full-text)

Criado PR, et al. Bedbugs (Cimicidae infestation): the worldwide renaissance of an old partner of human kind. Braz J Infect Dis. 2011 Feb;15(1):74-80. http://www.ncbi.nlm.nih.gov/pubmed/21412594 (with link to full-text)

National Geographic Video (2 minutes): http://www.youtube.com/watch?v=WfKCcSPCOQo

17. Flu Update: Antiviral Agents for the Treatment and Chemoprophylaxis of Influenza

CDC. Ann Emerg Med. 2011;58:299-303.

Influenza viruses can cause disease among persons in any age group, but rates of illness are highest among children.1, 2 During most influenza seasons, rates of serious illness and death are highest among persons aged 65 years or older, children younger than 2 years, and persons of any age who have medical conditions that place them at increased risk for complications from influenza.3, 4 In addition, data from epidemiologic studies conducted during the 2009 influenza A (H1N1) pandemic indicated that the risk for influenza complications was also increased among persons who are morbidly obese (body mass index ≥40 kg/m2) and American Indians/Alaska Natives.5, 6, 7, 8 In the postpandemic period, 2009 H1N1 virus strains now are considered to be the predominant seasonal influenza A (H1N1) virus strains. On the basis of epidemiologic studies of seasonal influenza or 2009 H1N1, persons at higher risk for influenza complications include:

• children younger than 5 years (especially those younger than 2 years);

• adults aged 65 years or older;

• persons with chronic pulmonary (including asthma), cardiovascular (except hypertension alone), renal, hepatic, hematologic (including sickle cell disease), or metabolic disorders (including diabetes mellitus) or neurologic and neurodevelopment conditions (including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy [seizure disorders], stroke, intellectual disability [mental retardation], moderate to severe developmental delay, muscular dystrophy, or spinal cord injury)9;

• persons with immunosuppression, including that caused by medications or by HIV infection;

• women who are pregnant or postpartum (within 2 weeks after delivery);

• persons aged 18 years or younger who are receiving long-term aspirin therapy;

• American Indians/Alaska Natives;

• persons who are morbidly obese (ie, body mass index ≥40 kg/m2); and

• residents of nursing homes and other chronic-care facilities.

For children, the risk for severe complications from seasonal influenza is highest among those younger than 2 years, who have much higher rates of hospitalization for influenza-related complications compared with older children.3 Medical care and emergency department (ED) visits attributable to influenza are increased among children younger than 5 years compared with older children.10

Annual influenza vaccination is the most effective method for preventing seasonal influenza virus infection and its complications. All persons aged 6 months or older should receive annual influenza vaccination.11 Antiviral medications are effective for the prevention of influenza and, when used for treatment, can reduce the duration and severity of illness.6, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 Early antiviral treatment can reduce the risk for severe illness or death related to influenza.6, 12, 23, 24, 25, 26, 27 However, the emergence of resistance to one or more of the 4 licensed antiviral agents (oseltamivir, zanamivir, amantadine, and rimantadine) among some circulating influenza virus strains during the past 5 years has complicated antiviral treatment and chemoprophylaxis recommendations. The selection of antiviral medications should be considered in the context of any available information about surveillance data on influenza antiviral resistance patterns among circulating influenza viruses; local, state, and national influenza surveillance information on influenza virus type or influenza A virus subtype; the characteristics of the person who is ill; and results of influenza testing if testing is conducted. Empiric antiviral treatment often is required to avoid treatment delays.28

Primary Changes and Updates in the Recommendations

These recommendations include 6 principal changes or updates from previous recommendations for use of antivirals for the prevention and control of influenza:

• Antiviral treatment is recommended as soon as possible for patients with confirmed or suspected influenza who have severe, complicated, or progressive illness or who require hospitalization.

• Antiviral treatment is recommended as soon as possible for outpatients with confirmed or suspected influenza who are at higher risk for influenza complications because of their age or underlying medical conditions; clinical judgment should be an important component of outpatient treatment decisions.

• Recommended antiviral medications include oseltamivir and zanamivir, according to recent viral surveillance and resistance data indicating that greater than 99% of currently circulating influenza virus strains are sensitive to these medications. Amantadine and rimantadine should not be used because of the high levels of resistance to these drugs among circulating influenza A viruses, but information about these drugs is provided for use if current recommendations change because of the reemergence of adamantane-susceptible strains.

• Oseltamivir may be used for treatment or chemoprophylaxis of influenza among infants younger than 1 year when indicated.

• Antiviral treatment also may be considered according to clinical judgment for any outpatient with confirmed or suspected influenza who does not have known risk factors for severe illness if treatment can be initiated within 48 hours of illness onset.

• Because antiviral resistance patterns can change over time, clinicians should monitor local antiviral resistance surveillance data.

The remainder of the text (free): http://www.annemergmed.com/article/S0196-0644(11)01304-7/fulltext

Abridged from MMWR Morb Mortal Wkly Rep. 2011;60:1-24. Full-text (free): http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6001a1.htm?s_cid=rr6001a1_w

18. Captain Morgan, The Rum Pirate, Lends A Knee To Hip Dislocation

Linda Thrasybule, NPR blog, August 12, 2011

If you were to dislocate your hip, you'd need the able hands of a physician to push your thighbone back into the socket where it belongs. But that effort of "reducing" a hip dislocation can be a tricky and even risky task.

That's why some doctors now look to Captain Morgan — yes, the pirate on the bottle of rum — for inspiration. If you've ever looked closely at the label, you might notice Morgan standing confidently, one foot on top of a barrel. That pose turns out to be a good way for doctors to apply force to the hip without having to crawl up on the patient's gurney.

A case series out this week in the Annals of Emergency Medicine found the technique to be a success for 12 out of 13 patients. But study authors caution that they haven't yet proved the technique is any faster, easier, or has fewer complications than other way of fixing hip dislocations.

"We actually started the technique in our hospital a couple of years ago," Gregory Hendey, a professor of clinical emergency medicine at the University of California, San Francisco, Fresno and one of the study authors, tells Shots. "One day, while watching a Captain Morgan's commercial, it just struck me that that's the position we do."

Hip dislocation happens when the head of the thighbone — the femur — slips out of its socket in the hipbone. Car accidents are the most common cause, according to the American Academy of Orthopedic Surgeons. People with hip replacements are also prone to them, as are athletes who play high contact sports like football.

"It's extremely painful," says Hendey. "You can't walk. You're incapacitated. It has to be taken care of immediately."

Other techniques for fixing hip dislocations can be precarious. Consider the Allis Maneuver, which requires the doctor to straddle the patient on a gurney, then bend the affected leg 90 degrees, while keeping the other leg down. The doctor then lifts the leg and applies force to the hip, popping the leg bone back into the hip socket. Doctors can injure their backs or fall off the gurney, the study said.

Although Hendey admits the study doesn't prove whether the Captain Morgan technique is better than other techniques, he does believe it's safer and easier for doctors to perform. "Once they start using the Captain, they never go back," he says.

Full-text (with an image of the Captain): http://www.npr.org/blogs/health/2011/08/12/139573713/captain-morgan-the-rum-pirate-lends-a-knee-to-hip-dislocation?ps=sh_sthdl

Hendley GW, et al. Ann Emerg Med 2011; in press. Full-text (currently free):
http://www.annemergmed.com/webfiles/images/journals/ymem/gwhendey.pdf

19. Value of post-resuscitation ECG in the diagnosis of AMI in out-of-hospital cardiac arrest patients

Sideris G, et al. Resuscitation. 2011;82:1148-1153.

Background: Diagnosis of acute myocardial infarction (AMI) in out-of-hospital cardiac arrest (OHCA) patients is important because immediate coronary angiography with coronary angioplasty could improve outcome in this setting. However, the value of acute post-resuscitation electrocardiographic (ECG) data for the detection of AMI is debatable.

Methods: We assessed the diagnostic characteristics of post-resuscitation ECG changes in a retrospective single centre study evaluating several ECG criteria of selection of patients undergoing AMI, in order to improve sensitivity, even at the expense of specificity. Immediate post resuscitation coronary angiogram was performed in all patients. AMI was defined angiographically using coronary flow and plaque morphology criteria.

Results: We included 165 consecutive patients aged 56 (IQR 48–67) with sustained return of spontaneous circulation after OHCA between 2002 and 2008. 84 patients had shockable, 73 non-shockable and 8 unknown initial rhythm; 36% of the patients had an AMI. ST-segment elevation predicted AMI with 88% sensitivity and 84% specificity. The criterion including ST-segment elevation and/or depression had 95% sensitivity and 62% specificity. The combined criterion including ST-segment elevation and/or depression, and/or non-specific wide QRS complex and/or left bundle branch block provided a sensitivity and negative predictive value of 100%, a specificity of 46% and a positive predictive value of 52%.

Conclusion: In patients with OHCA without obvious non-cardiac causes, selection for coronary angiogram based on the combined criterion would detect all AMI and avoid the performance of the procedure in 30% of the patients, in whom coronary angiogram did not have a therapeutic role.

20. Correction Factor for CSF Protein Levels in Traumatic Lumbar Puncture

Nigrovic LE et al. J Pediatr 2011 Jul; 159:158

Subtract 1.1 mg/dL protein for every 1000-cell increase in CSF red blood cell count.

Abstract: We sought to determine the relationship between cerebrospinal fluid (CSF) protein and CSF red blood cells in children with traumatic lumbar punctures. For every 1000 cell increase in CSF red blood cells per mm(3), CSF protein increases by 1.1 mg/dL (95% CI, 0.9-1.1 mg/dL).

21. More U.S. Children Being Diagnosed with Youthful Tendency Disorder

Redlands, CA--Nicholas and Beverly Serna's daughter Caitlin was just 4 years old, but they already knew there was a problem.

Day after day, upon arriving home from preschool, Caitlin would retreat into a bizarre fantasy world. Sometimes she would pretend to be people and things she was not. Other times, without warning, she would burst into nonsensical song. Some days she would run directionless through the backyard of the Sernas' comfortable Redlands home, laughing and shrieking as she chased imaginary objects. When months of sessions with a local psychologist failed to yield an answer, Nicholas and Beverly took Caitlin to a prominent Los Angeles pediatric neurologist for more exhaustive testing. Finally, on September 20, the Sernas received the heartbreaking news: Caitlin was among a growing legion of U.S. children suffering from Youthful Tendency Disorder.

"As horrible as the diagnosis was, it was a relief to finally know,' Beverly said. At least we knew we weren't bad parents.'

Youthful Tendency Disorder (YTD), a poorly understood neurological condition that afflicts an estimated 20 million U. S. children, is characterized by a variety of senseless, unproductive physical and mental exercises, often lasting hours at a time. In the thrall of YTD, sufferers run, jump, climb, twirl, shout, dance, do cartwheels, and enter unreal, unexplainable states of 'make-believe.'

Slowly, methodically through an elaborate system of rewards and punishments, Caitlin has shown improvement. But the road ahead is long.

"We get a lot of platitudes from the so-called experts,' Mr. Serna said. 'We hear a lot of, 'Oh, she'll grow out of it, just give it time.' That's easy for them to say--their kid's not running around the neighborhood claiming to be Superwoman."

Common YTD WARNING SIGNS
--Near constant running, jumping, skipping
--Sudden episodes of shouting and singing
--Preferring playtime and flights of fancy to schoolwork
--Confusing self with animals and object, including tiger, dinosaurs, and airplanes
--Conversations with "imaginary friends"
--Poor impulse control with regard to sugared snacks

Help for families struggling with YTD may soon be on the way. Last month, Pfizer unveiled Juvenol, a promising YTD drug which, pending FDA approval, could reach the U.S. market as early as next spring.

But until such help arrives, the parents of YTD sufferers can do little more than try to get through each day.

'I love my child with all my heart,' said Caitlin's mother. 'But when she's in the throes of one of her skipping fits, it's hard not to feel a little envious of parents with normal, healthy children.'"

The Onion. 2000;36:34.

22. Selected Readings that Promote Thriving, Personally and Globally

Kristoff and WuDunn, Half the Sky: Turning Oppression into Opportunity for Women Worldwide (New York: Knopf, 2011). http://www.halftheskymovement.org/

David Brooks, The Social Animal: The Hidden Sources of Love, Character, and Achievement (New York: Random House, 2011). http://www.thedailybeast.com/newsweek/2011/02/27/david-brooks-wants-to-be-friends.html

Wednesday, August 03, 2011

Lit Bits: Aug 3, 2011

From the recent medical literature...

1. Sensitivity of CT performed within six hours of onset of headache for diagnosis of SAH: prospective cohort study

Perry JJ, Stiell IG, et al. BMJ 2011; 343:d4277

Objective: To measure the sensitivity of modern third generation computed tomography in emergency patients being evaluated for possible subarachnoid haemorrhage, especially when carried out within six hours of headache onset.

Design: Prospective cohort study.

Setting: 11 tertiary care emergency departments across Canada, 2000-9.

Participants: Neurologically intact adults with a new acute headache peaking in intensity within one hour of onset in whom a computed tomography was ordered by the treating physician to rule out subarachnoid haemorrhage.

Main outcome measures: Subarachnoid haemorrhage was defined by any of subarachnoid blood on computed tomography, xanthochromia in cerebrospinal fluid, or any red blood cells in final tube of cerebrospinal fluid collected with positive results on cerebral angiography.

Results: Of the 3132 patients enrolled (mean age 45.1, 2571 (82.1%) with worst headache ever), 240 had subarachnoid haemorrhage (7.7%). The sensitivity of computed tomography overall for subarachnoid haemorrhage was 92.9% (95% confidence interval 89.0% to 95.5%), the specificity was 100% (99.9% to 100%), the negative predictive value was 99.4% (99.1% to 99.6%), and the positive predictive value was 100% (98.3% to 100%). For the 953 patients scanned within six hours of headache onset, all 121 patients with subarachnoid haemorrhage were identified by computed tomography, yielding a sensitivity of 100% (97.0% to 100.0%), specificity of 100% (99.5% to 100%), negative predictive value of 100% (99.5% to 100%), and positive predictive value of 100% (96.9% to 100%).

Conclusion: Modern third generation computed tomography is extremely sensitive in identifying subarachnoid haemorrhage when it is carried out within six hours of headache onset and interpreted by a qualified radiologist.

2. WHO Says Hospital Admission Far Riskier than Flying

By Stephanie Nebehay, Reuters Health Information. GENEVA, Jul 21 - Millions of people die each year from medical errors and infections linked to health care and going into hospital is far riskier than flying, the World Health Organization said on Thursday.

"If you were admitted to hospital tomorrow in any country... your chances of being subjected to an error in your care would be something like 1 in 10. Your chances of dying due to an error in health care would be 1 in 300," Dr. Liam Donaldson, the WHO's newly appointed envoy for patient safety, told a news briefing.

This compared with a risk of dying in an air crash of about 1 in 10 million passengers, according to Dr. Donaldson, formerly England's chief medical officer.

"It shows that health care generally worldwide still has a long way to go," he said.

Hundreds of millions of people suffer infections linked to health care each year. Patients should ask questions and be part of decision-making in hospitals, which must use basic hygiene standards and WHO's checklist to ensure safe surgical procedures were followed.

More than 50 percent of acquired infections can be prevented if health care workers clean their hands with soap and water or an alcohol-based handrub before treating patients.

Of every 100 hospitalized patients at any given time, 7 in developed and 10 in developing countries will acquire at least one health care-associated infection, according to the United Nations agency.

"The longer patients stay in an ICU (intensive care unit), the more at risk they become of acquiring an infection," it said. Medical devices such as urinary catheters and ventilators are associated with high infection rates.

'HIGH-RISK BUSINESS'

Each year in the United States, 1.7 million infections are acquired in hospital, leading to 100,000 deaths, a far higher rate than in Europe where 4.5 million infections cause 37,000 deaths, according to WHO.

"Health care is a high-risk business, inevitably, because people are sick and modern health care is delivered in a fast-moving, high-pressured environment involving a lot of complex technology and a lot of people," Dr. Donaldson said.

A heart operation can involve a team of up to 60 people, about the same number needed to run a jumbo jet, he said.

"Infection is a big problem, injuries after falls in hospitals is a big problem and then there are problems that are on a smaller scale but result in preventable deaths. Medication errors are common," he said.

Risk is even higher in developing countries, with about 15% of patients acquiring infections, said Dr. Benedetta Allegranzi of the WHO's "Clean Care is Safer Care" program.

"The risk is really higher in high-risk areas of the hospitals, in particular ICUs or neonatal units in developing countries."

About 100,000 hospitals worldwide now use the WHO's surgical safety checklist, which the agency said has been shown to reduce surgery complications by 33% and deaths by 50%.

If the checklist is effectively used worldwide, an estimated 500,000 deaths could be prevented each year, it says.

"Frankly, if I was having an operation tomorrow I wouldn't go into a hospital that wasn't using the checklist because I wouldn't regard it as safe," said Dr. Donaldson.

3. CLUE: a randomized Comparative effectiveness trial of IV nicardipine versus Labetalol Use in the ED

Peacock WF, et al. Crit Care. 2011 Jun 27;15(3):R157.

INTRODUCTION: Our purpose was to compare the safety and efficacy of food and drug administration (FDA) recommended dosing of IV nicardipine versus IV labetalol for the management of acute hypertension.

METHODS: Multicenter randomized clinical trial. Eligible patients had 2 systolic blood pressure (SBP) measures [greater than or equal to]180 mmHg and no contraindications to nicardipine or labetalol. Before randomization, the physician specified a target SBP +/- 20 mmHg (the target range: TR). The primary endpoint was the percent of subjects meeting TR during the initial 30 minutes of treatment.

RESULTS: Of 226 randomized patients, 110 received nicardipine and 116 labetalol. End organ damage preceded treatment in 143 (63.3%); 71 nicardipine and 72 labetalol patients. Median initial SBP was 212.5 (IQR 197, 230) and 212 mmHg (IQR 200,225) for nicardipine and labetalol patients (P=0.68), respectively. Within 30 minutes, nicardipine patients more often reached TR than labetalol (91.7 vs. 82.5%, P=0.039). Of 6 BP measures (taken every 5 minutes) during the study period, nicardipine patients had higher rates of five and six instances within TR than labetalol (47.3% vs. 32.8%, P=0.026). Rescue medication need did not differ between nicardipine and labetalol (15.5 vs. 22.4%, P=0.183). Labetalol patients had slower heart rates at all time points (P less than 0.01). Multivariable modeling showed nicardipine patients were more likely in TR than labetalol patients at 30 minutes (OR 2.73, P=0.028; C stat for model = 0.72)

CONCLUSION: Patients treated with nicardipine are more likely to reach the physician-specified SBP target range within 30 minutes than those treated with labetalol.

Full-text (free): http://ccforum.com/content/pdf/cc10289.pdf

4. EM Myths Exploded: ED Care Less Than 2% of Health Care Spending

Berger E. Ann Emerg Med. 2011;58:A18-A20.

Coffee sobers you up.

Going out in cold weather makes you sick.

Too much sugar makes your kids hyperactive.

Chewing gum, once swallowed, takes 7 years to digest.

To be safe, wait 30 minutes after eating before swimming.

Taking vitamin C, echinacea, or zinc prevents colds.

These are half a dozen medical myths that much of the American population, and even more than a handful of physicians, believes. Here's one more: Emergency medical care is expensive and inefficient.

Readers of this article probably won't be taken in by that myth, but in this respect, readers of this journal are out of step with the general public and, perhaps still more important, policymakers. Consider a Senate bill (SB 1781) introduced in October 2009, called the Reducing Emergency Department Utilization Through Coordination and Empowerment (REDUCE) Act. According to its language, the bill sought to address emergency department (ED) overuse, improve quality of care, and save taxpayers' money by establishing pilot programs to better coordinate care for frequent ED users.

“Far too many people rely on emergency room services for routine or primary care,” said US Senator Sherrod Brown (D-OH), one of the bill's authors. ”By strategically expanding outreach services to frequent ER visitors and better coordinating their care, we can cut the associated costs to taxpayers. This initiative takes an important step toward fixing our broken health care system and improving the quality of care for communities in Ohio and across the country.”

Brown is not alone in holding such beliefs. In March 2011, Health and Human Services Secretary Kathleen Sebelius joined the public radio talk program The Diane Rehm Show and responded to a small business owner in Nantucket, MA, who was concerned about paying $1,600 per month for health insurance coverage for her family of 3 under the state's universal health insurance plan, with a $5,000 deductible because of her son's preexisting condition.

“Right now, as a taxpayer, the family from Nantucket is also paying for everyone who doesn't have insurance who is coming through emergency room doors accessing the health care system, often in a very expensive way,” Sebelius said.

In recognition of this pervasive myth about emergency care, as well as others, the American College of Emergency Physicians (ACEP) launched the “Just 2% Campaign” in April 2011. The national public education campaign seeks to promote the value of emergency medicine and to educate the public and policymakers that emergency care is less than 2% of the nation's health care dollar.

During a talk at ACEP's Health Writer's Conference in New York City on April 19, President Sandra Schneider, MD, a professor and chair emeritus in the Department of Emergency Medicine, University of Rochester, Rochester, NY, laid out the campaign for members of the media.

“Health care spending is a huge issue in the United States, representing more than 16% of our gross domestic product. Yet, as became clear during the health care reform debate last year, there are misconceptions about the costs and efficiencies of emergency rooms,” she said. “The bottom line is this: Policymakers seeking to trim fat from the nation's rising health care bills are looking in the wrong place if they take aim at emergency departments.”

ACEP launched the campaign amid a widespread rhetoric from policymakers, public policy wonks, and some sectors of the health care industry on the need to reduce visits to the ED as a way to control increasing health care costs. This article, then, seeks to amplify this educational effort by dispelling the “too costly” myth, as well as others being bandied about by politicians and the press.

Myth No. 1: Emergency Care is Too Expensive…

Myth No. 2: EDs are Crowded by Patients with Nonurgent Medical Issues…

Myth No. 3: Undocumented Immigrants Cause ED crowding…

Myth No. 4: Health Care Reform Will Lead to a Substantial Reduction in Costly ED Visits…

The remainder of the essay can be found here (full-text free): http://www.annemergmed.com/article/S0196-0644(11)00617-2/fulltext

5. Stable Patients with Pulmonary Embolism Can Be Treated as Outpatients

In a randomized trial of outpatient versus inpatient care, outcomes did not differ between groups.

Typically, diagnosis of pulmonary embolism (PE) means certain admission. Researchers performed an open-label, randomized, noninferiority study to compare outcomes of outpatient and inpatient treatment in consecutive adult patients who presented to 19 emergency departments in Europe and the U.S. with symptomatic PE and risk for death less than 4% (based on the PE Severity Index; see table). Patients were excluded if they had oxygen saturation below 90% on room air, systolic blood pressure below 100 mm Hg, chest pain requiring opioids, active bleeding, or were at high risk for hemorrhage (recent stroke or gastrointestinal bleeding or platelet count above 75,000/mm3). All patients initially received subcutaneous enoxaparin (1 mg/kg twice daily) followed by anticoagulation with vitamin K antagonists for at least 90 days.

Overall, the study included 171 outpatients (mean age, 47) and 168 inpatients (mean age, 49). Cancer prevalence was 1% and 2%, respectively. Within 90 days, one patient in each group died, neither from PE. Recurrent venous thromboembolism occurred in only one patient (outpatient group). Major bleeding occurred within 90 days in three outpatients (intramuscular hematoma on day 3 and day 13 and menometrorrhagia on day 50) and no inpatients. At 14 days, more than 90% of patients in both groups were satisfied or very satisfied with treatment.

Comment: These data suggest that stable low-risk patients with PE can be safely and effectively treated as outpatients with low-molecular-weight heparin. The results might not be applicable to older patients than those in this study or to patients with cancer.

— Kristi L. Koenig, MD, FACEP. Published in Journal Watch Emergency Medicine July 22, 2011. Citation: Aujesky D et al. Outpatient versus inpatient treatment for patients with acute pulmonary embolism: An international, open-label, randomised, non-inferiority trial. Lancet 2011 Jul 2; 378:41.

Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21703676

6. MRSA Superbug: Can Coffee And Tea Protect You?

Meghan Neal, The Huffington Post. Posted: 7/15/11.

More good news for coffee drinkers? Possibly.

A government study looked at 5,500 Americans and found those that drank tea or coffee had half the chance of carrying the MRSA superbug in their nasal carriage. Scientists have long been aware of tea and coffee's antimicrobial properties.

"Our findings raise the possibility of a promising new method to decrease MRSA nasal carriage that is safe, inexpensive, and easily accessible," wrote the study authors in the Annals Of Family Medicine.

Still, more research is needed. Lead researcher Eric Matheson, of the University of South Carolina, told Reuters: “The study shows an association between the two, but you never can conclude causation from an association. I can't tell you that this finding isn't just a coincidence.”

Since its discovery in the early 1960s, the antibiotic-resistant "superbug" MRSA, short for Methicillin-resistant Staphylococcus Aureus, has been quickly spreading across the U.S. and oversees -- suggesting epidemic levels.

In June a new strain of MRSA was discovered in cow's milk. While alarming, researchers said it was unlikely the bacteria would seep into the food chain.

Matheson EM, et al. Ann Family Med 2011;9:299-304. Abstract: http://www.annfammed.org/cgi/content/abstract/9/4/299

7. Do Children With Blunt Head Trauma and Normal Cranial CT Scan Results Require Hospitalization for Neurologic Observation?

Holmes JF, et al with PECARN Network. Ann Emerg Med. Article in press.

Study objective: Children evaluated in the emergency department (ED) with minor blunt head trauma, defined by initial Glasgow Coma Scale (GCS) scores of 14 or 15, are frequently hospitalized despite normal cranial computed tomography (CT) scan results. We seek to identify the frequency of neurologic complications in children with minor blunt head trauma and normal ED CT scan results.

Methods: We conducted a prospective, multicenter observational cohort study of children younger than 18 years with blunt head trauma (including isolated head or multisystem trauma) at 25 centers between 2004 and 2006. In this substudy, we analyzed individuals with initial GCS scores of 14 or 15 who had normal cranial CT scan results during ED evaluation. An abnormal imaging study result was defined by any intracranial hemorrhage, cerebral edema, pneumocephalus, or any skull fracture. Patients with normal CT scan results who were hospitalized were followed to determine neurologic outcomes; those discharged to home from the ED received telephone/mail follow-up to assess for subsequent neuroimaging, neurologic complications, or neurosurgical intervention.

Results: Children (13,543) with GCS scores of 14 or 15 and normal ED CT scan results were enrolled, including 12,584 (93%) with GCS scores of 15 and 959 (7%) with GCS scores of 14. Of 13,543 patients, 2,485 (18%) were hospitalized, including 2,107 of 12,584 (17%) with GCS scores of 15 and 378 of 959 (39%) with GCS scores of 14. Of the 11,058 patients discharged home from the ED, successful telephone/mail follow-up was completed for 8,756 (79%), and medical record, continuous quality improvement, and morgue review was performed for the remaining patients. One hundred ninety-seven (2%) children received subsequent CT or magnetic resonance imaging (MRI); 5 (0.05%) had abnormal CT/MRI scan results and none (0%; 95% confidence interval [CI] 0% to 0.03%) received a neurosurgical intervention. Of the 2,485 hospitalized patients, 137 (6%) received subsequent CT or MRI; 16 (0.6%) had abnormal CT/MRI scan results and none (0%; 95% CI 0% to 0.2%) received a neurosurgical intervention. The negative predictive value for neurosurgical intervention for a child with an initial GCS score of 14 or 15 and a normal CT scan result was 100% (95% CI 99.97% to 100%).

Conclusion: Children with blunt head trauma and initial ED GCS scores of 14 or 15 and normal cranial CT scan results are at very low risk for subsequent traumatic findings on neuroimaging and extremely low risk of needing neurosurgical intervention. Hospitalization of children with minor head trauma after normal CT scan results for neurologic observation is generally unnecessary.

8. Discontinuation of low dose aspirin and risk of MI

Individuals with a history of cardiovascular events who stop taking low dose aspirin are at increased risk of non-fatal myocardial infarction compared with those who continue treatment, say the authors of this case-control study in UK primary care. Editorialists Giuseppe Biondi-Zoccai and Giovanni Landoni say that these findings are important and support previous studies showing an increase in adverse events after aspirin withdrawal. They suggest that patients should be advised never to stop aspirin unless explicitly told to do so, and doctors should maintain their patients on low dose aspirin for as long as they can.

García Rodríguez LA, et al. BMJ 2011; 343:d4094

Objective:s To evaluate the risk of myocardial infarction and death from coronary heart disease after discontinuation of low dose aspirin in primary care patients with a history of cardiovascular events.

Design: Nested case-control study.

Setting: The Health Improvement Network (THIN) database in the United Kingdom.

Participants: Individuals aged 50-84 with a first prescription for aspirin (75-300 mg/day) for secondary prevention of cardiovascular outcomes in 2000-7 (n=39 513).

Main outcome measures: Individuals were followed up for a mean of 3.2 years to identify cases of non-fatal myocardial infarction or death from coronary heart disease. A nested case-control analysis assessed the risk of these events in those who had stopped taking low dose aspirin compared with those who had continued treatment.

Results: There were 876 non-fatal myocardial infarctions and 346 deaths from coronary heart disease. Compared with current users, people who had recently stopped taking aspirin had a significantly increased risk of non-fatal myocardial infarction or death from coronary heart disease combined (rate ratio 1.43, 95% confidence interval 1.12 to 1.84) and non-fatal myocardial infarction alone (1.63, 1.23 to 2.14). There was no significant association between recently stopping low dose aspirin and the risk of death from coronary heart disease (1.07, 0.67 to 1.69). For every 1000 patients, over a period of one year there were about four more cases of non-fatal myocardial infarction among patients who discontinued treatment with low dose aspirin (recent discontinuers) compared with patients who continued treatment.

Conclusions: Individuals with a history of cardiovascular events who stop taking low dose aspirin are at increased risk of non-fatal myocardial infarction compared with those who continue treatment.

Full-text (free): http://www.bmj.com/content/343/bmj.d4094

9. Current methods of diagnosis and treatment of scaphoid fractures

Rhemrev SJ, et al. International J Emerg Med. 2011;4:4

Fractures of the scaphoid bone mainly occur in young adults and constitute 2-7% of all fractures. The specific blood supply in combination with the demanding functional requirements can easily lead to disturbed fracture healing. Displaced scaphoid fractures are seen on radiographs. The diagnostic strategy of suspected scaphoid fractures, however, is surrounded by controversy. Bone scintigraphy, magnetic resonance imaging and computed tomography have their shortcomings. Early treatment leads to a better outcome. Scaphoid fractures can be treated conservatively and operatively. Proximal scaphoid fractures and displaced scaphoid fractures have a worse outcome and might be better off with an open or closed reduction and internal fixation. The incidence of scaphoid non-unions has been reported to be between 5 and 15%. Non-unions are mostly treated operatively by restoring the anatomy to avoid degenerative wrist arthritis.

Full-text (free): http://www.springerlink.com/content/x1k754879q244222/fulltext.pdf

10. Rocuronium Versus Succinylcholine: Cochrane Synopsis Reconsidered

Strayer RJ, et al. Ann Emerg Med. 2011;58:217-218.

To the Editor:

I read with interest the summary by Seupaul and Jones1 of the 2008 Cochrane systematic review comparing intubating conditions produced by rocuronium and succinylcholine during rapid sequence intubation. The summary reports the study's conclusion, which is that succinylcholine produces excellent intubating conditions more frequently than rocuronium, with a relative risk of 0.86. This result is taken from 37 studies, of which 24 used rocuronium at a dose of 0.6 mg/kg, 5 used a dose of 0.9 mg/kg or greater, and 8 used a combination of doses.

The speed with which rocuronium causes paralysis is dose dependent. At the classically recommended dose of 0.6 mg/kg, excellent intubating conditions are significantly delayed. At 1.0 mg/kg, excellent intubating conditions are produced at 60 seconds, about 15 seconds later than with succinylcholine. At 1.2 mg/kg, the currently recommended dose, rocuronium produces excellent intubating conditions at 40 seconds and cannot be distinguished from succinylcholine.2 In fact, the authors of the Cochrane review state, “We found no statistical difference in intubation conditions when succinylcholine was compared to 1.2 mg/kg rocuronium.” A recent emergency department (ED)–based head-to-head comparison supports this conclusion.3

The Cochrane authors follow this evidence-based result with the following assertion: “…[H]owever, succinylcholine was clinically superior as it has a shorter duration of action.” Mallon et al4 used a similar argument in their cited critical appraisal.

The longer duration of action of rocuronium is an advantage, not a disadvantage. Emergency clinicians who believe they are protected against a can't-intubate, can't-ventilate scenario by the short duration of succinylcholine are usually wrong5 and make dangerous decisions as a result. When early attempts at laryngoscopy fail, further attempts are hindered by the return of the patient's airway reflexes; this already precarious situation is worsened if the patient puts his now-functioning muscles to use by vomiting.

These problems are eliminated by the longer duration of rocuronium. Furthermore, rocuronium is not burdened by a list of rare but lethal contraindications, most of which are not routinely screened for by emergency physicians. Succinylcholine also occasionally causes masseter spasm, rendering laryngoscopy impossible until a nondepolarizing paralytic is located and administered.

In conclusion, succinylcholine is more likely to produce excellent intubating conditions than rocuronium only if the incorrect dose of rocuronium is used. At 1.2 mg/kg, rocuronium is as effective as succinylcholine at facilitating laryngoscopy and offers a host of other advantages. Although both drugs are safe and effective for rapid sequence intubation in the ED, rocuronium should be the preferred agent in most circumstances.

References: http://www.annemergmed.com/article/S0196-0644(11)00281-2/fulltext

11. Ultrasound-Guided Central Line Placement: No X-Ray Needed?

No pneumothoraces were detected on chest x-ray in 1202 asymptomatic patients after ultrasound-guided central venous line placement.

With ultrasound-guided central line placement, is a postinsertion chest x-ray still necessary to assess for pneumothorax? Researchers reviewed records for 1258 real-time, ultrasound-guided, internal jugular vein central line placements and 4 external jugular vein placements performed in 1066 patients during 4 years in the vascular and interventional radiology suite at a single U.S. hospital.

Postprocedure upright chest x-rays were obtained in 1202 patients (after an average of 65 minutes); supine chest x-rays were performed as part of routine care in 66 hospitalized and bedridden patients. No patient had symptoms or radiographic evidence of pneumothorax. The authors conclude that eliminating routine postprocedure x-rays would save time and costs and reduce radiation exposure.

Comment: This study was performed in a more controlled environment than an emergency department. Chest x-ray is not necessary after ultrasound-guided internal jugular vein cannulation when assessment of catheter positioning is not needed. When pneumothorax is suspected, bedside ultrasound for lung sliding likely is a better test than a chest x-ray (JW Emerg Med Nov 6 2009).

— Kristi L. Koenig, MD, FACEP. Published in Journal Watch Emergency Medicine July 29, 2011. Citation: Oner B et al. Pneumothorax following ultrasound-guided jugular vein puncture for central venous access in interventional radiology: 4 years of experience. J Intensive Care Med 2011 Jul 14; [e-pub ahead of print].

12. Children Presenting With Acute Pericarditis to the ED

Ratnapalan S, et al, Pediatr Emerg Care. 2011;27(7):581-585.

Objective: The objective of the study was to evaluate the clinical features and the outcome of children who presented to the emergency department and were ultimately diagnosed with pericarditis.

Methods: A retrospective chart review of all children diagnosed with acute pericarditis from January 2000 through March 2007 was conducted.

Results: There were 94 children with pericarditis as the sole or one of the discharge diagnoses: 34 with postsurgical pericarditis and 38 with pericarditis as a component of a generalized illness were not examined further. Of the 22 children included in the study, the mean age was 12.3 (SD, 2.7) years, and 80% were males. Chest pain was present in 96%, and fever was present in 56%. All children had electrocardiographic changes comprising ST and T-wave abnormalities. Initial chest radiographs were reported as normal in 40%; although 82% (n = 18) had a pericardial effusion on echocardiography, 7 (32%) required pericardiocentesis. The etiology was considered idiopathic in 68% (n = 15). All children improved on treatment with nonsteroidal anti-inflammatory drugs. Eight children (36%) had recurrent pericarditis, of whom 2 had multiple recurrences.

Conclusions: Children presenting with chest pain require further investigation if electrocardiographs show any abnormalities. Children presenting with pericarditis require follow-up and caution about recurrence.

13. Association of Hospitalist Care with Medical Utilization After Discharge: Evidence of Cost Shift From a Cohort Study

Kuo YF, et al. Ann Intern Med 2011;155:152-159.

Most studies of hospitalist care have focused on the inpatient stay. This study compared hospitalized patients who were cared for by primary care physicians with those cared for by hospitalists. Hospitalists' patients had shorter and less expensive hospitalizations. During the 30 days after discharge, however, hospitalists' patients had more visits to the emergency department, more readmissions to the hospital, and higher total expenses. Savings during hospitalization that are associated with hospitalist care may be offset by higher expenses after discharge.

Abstract: http://www.annals.org/content/155/3/152.abstract

14. Accuracy of Stated Energy Contents of Restaurant Foods

Urban LE, et al. JAMA. 2011 Jul 20;306(3):287-93.

Context: National recommendations for the prevention and treatment of obesity emphasize reducing energy intake. Foods purchased in restaurants provide approximately 35% of the daily energy intake in US individuals but the accuracy of the energy contents listed for these foods is unknown.

Objective: To examine the accuracy of stated energy contents of foods purchased in restaurants.

Design and Setting: A validated bomb calorimetry technique was used to measure dietary energy in food from 42 restaurants, comprising 269 total food items and 242 unique foods. The restaurants and foods were randomly selected from quick-serve and sit-down restaurants in Massachusetts, Arkansas, and Indiana between January and June 2010.

Main Outcome Measure: The difference between restaurant-stated and laboratory-measured energy contents, which were corrected for standard metabolizable energy conversion factors.

Results: The absolute stated energy contents were not significantly different from the absolute measured energy contents overall (difference of 10 kcal/portion; 95% confidence interval [CI], −15 to 34 kcal/portion; P = .52); however, the stated energy contents of individual foods were variable relative to the measured energy contents. Of the 269 food items, 50 (19%) contained measured energy contents of at least 100 kcal/portion more than the stated energy contents. Of the 10% of foods with the highest excess energy in the initial sampling, 13 of 17 were available for a second sampling. In the first analysis, these foods contained average measured energy contents of 289 kcal/portion (95% CI, 186 to 392 kcal/portion) more than the stated energy contents; in the second analysis, these foods contained average measured energy contents of 258 kcal/portion (95% CI, 154 to 361 kcal/portion) more than the stated energy contents (P less than.001 for each vs 0 kcal/portion difference). In addition, foods with lower stated energy contents contained higher measured energy contents than stated, while foods with higher stated energy contents contained lower measured energy contents (P less than.001).

Conclusions: Stated energy contents of restaurant foods were accurate overall. However, there was substantial inaccuracy for some individual foods, with understated energy contents for those with lower energy contents.

15. Images in Emergency Medicine

Elderly Female with Syncope
http://www.annemergmed.com/article/S0196-0644(10)01705-1/fulltext

Man with Generalized Weakness
http://www.annemergmed.com/article/S0196-0644(10)01649-5/fulltext

Infant With Facial Lesions
http://www.annemergmed.com/article/S0196-0644(11)00024-2/fulltext

Woman With Hypertension and Seizure
http://www.annemergmed.com/article/S0196-0644(11)00022-9/fulltext

Small-Intestinal Volvulus
http://www.nejm.org/doi/full/10.1056/NEJMicm0806895

Evolution of a Jellyfish Sting
http://www.nejm.org/doi/full/10.1056/NEJMicm1009713

Angioedema
http://www.nejm.org/doi/full/10.1056/NEJMicm1014034

Thrombosis of the Inferior Vena Cava and Dilated Veins of the Trunk
http://www.nejm.org/doi/full/10.1056/NEJMicm1010652

Dependent Rubor
http://www.nejm.org/doi/full/10.1056/NEJMicm1010160

16. IV Volume Expansion Helpful in Hemolytic Uremic Syndrome

Laurie Barclay, MD. Medscape News. July 25, 2011 — In children who have diarrhea and are at risk for hemolytic uremic syndrome (HUS), intravenous volume expansion may help protect against oligoanuric renal failure, according to the results of a prospective, observational cohort study reported online July 22 in the Archives of Pediatrics and Adolescent Medicine. Since an Escherichia coli outbreak was first reported in Germany in May 2011, there have been more than 900 cases of HUS reported in 16 countries in Europe and North America.

"[T]he pathophysiologic cascade leading to renal failure might provide an opportunity to mitigate renal damage," write Christina A. Hickey, MD, from Washington University School of Medicine and St. Louis Children's Hospital, Missouri, and colleagues. "If patients at risk for HUS are recognized early in illness, then the brief interval between first presentation with diarrhea and HUS onset could be exploited to maintain or improve renal perfusion, possibly averting renal shutdown."

The study goal was to assess the effect of interventions during the pre-HUS diarrhea phase on maintenance of urine output during HUS. At 11 pediatric hospitals in the United States and Scotland, children younger than 18 years with diarrhea-associated HUS received intravenous fluid within the first 4 days of diarrhea onset. Inclusion criteria were hematocrit level lower than 30% with smear evidence of intravascular erythrocyte destruction, thrombocytopenia with platelet count lower than 150 × 103/mm3, and impaired renal function, defined as serum creatinine concentration higher than the upper limit of reference range for age. The main study endpoint was presence or absence of oligoanuria, defined as a urine output of 0.5 mL/kg/hour or less for more than 1 day.

Among the 50 participants, the overall oligoanuric rate was 68%, but those who received no intravenous fluids in the first 4 days of illness had an oligoanuric rate of 84%. When fluids were not given during this time, the relative risk for oligoanuria was 1.6 (95% confidence interval, 1.1 - 2.4; P = .02).

Compared with children without oligoanuria, those with oligoanuric HUS received less total intravenous fluid (r = −0.32; P = .02) and sodium (r = −0.27; P = .05) during the first 4 days of illness. The most significant covariate in multivariable analysis was volume infused, but volume and sodium strongly covaried.

"Intravenous volume expansion is an underused intervention that could decrease the frequency of oligoanuric renal failure in patients at risk of HUS," the study authors write.

Limitations of this study include the lack of randomization and the inability to address the optimal sodium content of the fluid given or the value or safety of isotonic intravenous volume expansion in children whose serum creatinine concentrations are rising, but who are still urinating.

"Because presence and/or duration of oligoanuria are so repeatedly associated with long-term sequelae in children with HUS, it seems appropriate to prioritize maintenance of urine output during HUS, even though our data do not permit us to state that pre-HUS intravenous volume expansion prevents long-term renal sequelae," the study authors conclude. "Intravenous volume expansion appears to be a logical strategy that can be used now to achieve this goal, because we cannot hasten renal recovery once oligoanuria is established. We reiterate that volume expansion in these situations must be accompanied by assiduous monitoring for cardiopulmonary overload and hypertension."

The Doris Duke Clinical Research Fellowship supported this study. The study authors have disclosed no relevant financial relationships.

Arch Pediatr Adolesc Med. 2011 Jul 22. PubMed Abstract: http://www.ncbi.nlm.nih.gov/pubmed/21784993

17. A Task Analysis of Emergency Physician Activities in Academic and Community Settings

Chisholm CD, et al. Ann Emerg Med. 2011;58:117-122.

Study objective: We characterize and compare the work activities, including peak patient loads, associated with the workplace in the academic and community emergency department (ED) settings. This allows assessment of the effect of future ED system operational changes and identifies potential sources contributing to medical error.

Methods: This was an observational, time-motion study. Trained observers shadowed physicians, recording activities. Data included total interactions, distances walked, time sitting, patients concurrently treated, interruptions, break in tasks, physical contact with patients, hand washing, diagnostic tests ordered, and therapies rendered. Activities were classified as direct patient care, indirect patient care, or personal time with a priori definitions.

Results: There were 203 2-hour observation periods of 85 physicians at 2 academic EDs with 100,000 visits per year at each (N=160) and 2 community EDs with annual visits of 19,000 and 21,000 (N=43). Reported data present the median and minimum-maximum values per 2-hour period. Emergency physicians spent the majority of time on indirect care activities (academic 64 minutes, 29 to 91 minutes; community 55 min, 25 to 95 minutes), followed by direct care activities (academic 36 minutes, 6 to 79 minutes; community 41 minutes, 5 to 60 minutes). Personal time differed by location type (academic 6 minutes, 0 to 66 minutes; community 13 minutes, 0 to 69 minutes). All physicians simultaneously cared for multiple patients, with a median number of patients greater than 5 (academic 7 patients, 2 to 16 patients; community 6 patients, 2 to 12 patients).

Conclusion: Emergency physicians spend the majority of their time involved in indirect patient care activities. They are frequently interrupted and interact with a large number of individuals. They care for a wide range of patients simultaneously, with surges in multiple patient care responsibilities. Physicians working in academic settings are interrupted at twice the rate of their community counterparts.

18. Examination of staphylococcal stethoscope contamination in the ED

Tang PHP, et al. CJEM 2011;13(4):239-244

Introduction: The objective of this study was to determine the prevalence of Staphylococcus-contaminated stethoscopes belonging to emergency department (ED) staff and to identify the proportion of these that were Staphylococcus aureus or methicillin-resistant Staphylococcus aureus (MRSA).

Methods: We conducted a prospective observational cohort study of bacterial cultures from 100 ED staff members' stethoscopes at three EDs. Study participants were asked to complete a questionnaire.

Results: Fifty-four specimens grew coagulase-negative staphylococci and one grew methicillin-susceptible S. aureus. No MRSA was cultured. Only 8% of participants, all of whom were nurses, reported cleaning their stethoscope before or after each patient assessment. Alcohol-based wipes were most commonly used to clean stethoscopes. A lack of time, being too busy, and forgetfulness were the most frequently reported reasons for not cleaning the stethoscope in the ED.

Conclusions: This study indicates that although stethoscope contamination rates in these EDs are high, the prevalence of S. aureus or MRSA on stethoscopes is low.

19. Interexaminer Agreement in Physical Examination for Children with Suspected Soft Tissue Abscesses

Giovanni JE. Pediatr Emerg Care. 2011;27(6):475-478.

Objective: This study aimed to measure interexaminer agreement for physical examination (PE) findings in children with a suspected soft tissue abscess.

Methods: A prospective study was conducted from March 1 to July 31, 2007, at an urban, tertiary care children's hospital emergency department. Children presenting to the emergency department with a suspected local skin abscess were independently examined by 2 physicians. Interrater agreement of 7 PE findings for children with a suspected soft tissue abscess was assessed. Interrater agreement was calculated for the diagnosis of the lesion and decision to incise and drain.

Results: A total of 105 paired observations were completed by a total of 27 physicians. The patients examined were aged 2 weeks to 18 years, with a mean age of 80 months. Lesions were most frequently encountered on the buttocks (38%). Incision and drainage was attempted in 75% of cases, with purulent material obtained in 92% of all attempts. Interrater agreement was substantial for erythema (κ = 0.66) and size of the lesion (intraclass correlation coefficient = 0.78), moderate for drainage (κ = 0.57) and tenderness (κ = 0.40), fair for fluctuance (κ = 0.35), and poor for warmth (κ = 0.15) and showed no agreement for induration (κ = −0.08). There was moderate agreement on diagnosing the lesion as an abscess (κ = 0.48) and determination if the lesion required incision and drainage (κ = 0.44).

Conclusions: Interexaminer agreement of examination findings and diagnosis of an abscess was fair to moderate, implying a lack of precision of PE as the primary means for diagnosis. Future studies of diagnostic adjuncts, such as bedside ultrasonography, may lead to improved management of soft tissue infections in children.

20. ED Management of Patients on Warfarin Therapy

Meeker E, et al. Ann Emerg Med. 2011;58:192-199.

Study objective: To characterize warfarin management in the emergency department (ED).

Methods: This was a retrospective, cross-sectional, observational study of patients who were receiving warfarin and were discharged from a tertiary care, academic urban ED between June and August 2007. We abstracted patient demographics, presenting complaint, international normalized ratio (INR) if tested, indication for warfarin if documented, new medications administered or prescribed in the ED, and discharge instructions. Presenting complaints were categorized according to whether they were warfarin-related and concerning for thrombosis or bleeding. The primary outcome measure was the prevalence of warfarin therapy. The secondary outcome measures were frequency with which ED providers obtained an INR result, response to nontherapeutic results, administration or prescription of interacting medications, and percentage of patients receiving recommendations for anticoagulation follow-up.

Results: Two percent (111/7,195) of all patients presenting to and discharged from the ED during the study period were found to be receiving warfarin. Seventy-one percent (79/111) had an INR checked. Nontherapeutic INRs were recorded for 49% (39/79) of patients; ED providers intervened to address these results in 21% (8/39) of cases. Seventy-one percent (5/7) of patients with a supratherapeutic INR received an intervention compared with 9% (3/32) of patients with a subtherapeutic INR. Seventeen percent (19/111) and 13% (14/111) of patients received or were prescribed potentially interacting medications, respectively. Recommendations for specific anticoagulation follow-up were documented for 19% (21/111) of all patients.

Conclusion: Patients receiving warfarin frequently present to the ED and often have nontherapeutic INRs. Potential areas for improvement in ED management include greater attention to subtherapeutic INRs, interacting medications, and discharge planning.

21. Performance of stroke risk scores in older people with atrial fibrillation not taking warfarin: comparative cohort study from BAFTA trial

Hobbs FDR, et al. BMJ 2011; 342:d3653

Objective: To compare the predictive power of the main existing and recently proposed schemes for stratification of risk of stroke in older patients with atrial fibrillation.

Design: Comparative cohort study of eight risk stratification scores.

Setting: Trial of thromboprophylaxis in stroke, the Birmingham Atrial Fibrillation in the Aged (BAFTA) trial.

Participants: 665 patients aged 75 or over with atrial fibrillation based in the community who were randomised to the BAFTA trial and were not taking warfarin throughout or for part of the study period.

Main outcome measures: Events rates of stroke and thromboembolism.

Results: 54 (8%) patients had an ischaemic stroke, four (0.6%) had a systemic embolism, and 13 (2%) had a transient ischaemic attack. The distribution of patients classified into the three risk categories (low, moderate, high) was similar across three of the risk stratification scores (revised CHADS2, NICE, ACC/AHA/ESC), with most patients categorised as high risk (65-69%, n=460-457) and the remaining classified as moderate risk. The original CHADS2 (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes, previous Stroke) score identified the lowest number as high risk (27%, n=180). The incremental risk scores of CHADS2, Rietbrock modified CHADS2, and CHA2DS2-VASc (CHA2DS2-Vascular disease, Age 65-74 years, Sex) failed to show an increase in risk at the upper range of scores. The predictive accuracy was similar across the tested schemes with C statistic ranging from 0.55 (original CHADS2) to 0.62 (Rietbrock modified CHADS2), with all except the original CHADS2 predicting better than chance. Bootstrapped paired comparisons provided no evidence of significant differences between the discriminatory ability of the schemes.

Conclusions: Based on this single trial population, current risk stratification schemes in older people with atrial fibrillation have only limited ability to predict the risk of stroke. Given the systematic undertreatment of older people with anticoagulation, and the relative safety of warfarin versus aspirin in those aged over 70, there could be a pragmatic rationale for classifying all patients over 75 as “high risk” until better tools are available.

Full-text (free): http://www.bmj.com/content/342/bmj.d3653.full