The optimal emergency department (ED) evaluation of syncope is uncertain. Research reports from multiple countries suggest extensive practice variation, high costs, and questionable benefit associated with current approaches.1–5 Moreover, only a few of the recommendations from international syncope guidelines deal with ED management.6–8 For example, the European Society of Cardiology guidelines, which are the most inclusive syncope guidelines, do not address the ED management. This could be due to limited evidence on how to stratify the risk and decide on disposition of these patients in the ED.1,9 We organized a multi-specialty workshop of North American and European syncope experts on 26–27 September 2013 in Gargnano, Italy, with the aim of obtaining a modified Delphi consensus on the best way to manage ED syncope patients. As already described,10 we followed a four-step conceptual model for the ED decision-making in syncope: (i) Is it syncope? (ii) Is there a serious underlying condition identified in the ED? (iii) If the cause is uncertain, what is the risk of a serious outcome? (iv) For a given risk profile, how can these patients be best managed in the ED and what evaluation and restrictions are required? ( Figure 1 ) . Figure 1 Conceptual model: ED management of syncope. Expert recruitment and consensus development have been described previously.10 Details can be found in Supplementary material online, Appendix S1 . The full list of questions and answers to the first and second survey rounds as well as the degree of agreement on each item is reported in Supplementary material online, Appendix S2 . According to the ESC guidelines, syncope is defined as a …

B-type natriuretic peptides (BNPs) have been investigated as biomarkers for risk stratification of patients with syncope. Their concentration can be influenced by age and co-morbidities. In the present study, we compared the change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels within 6 hours in patients with vasovagal and arrhythmic syncope to determine whether this change can predict arrhythmic syncope. Using a case-control design, 33 patients were enrolled. Of the 33 patients, 18 with arrhythmic syncope, as they underwent controlled ventricular tachycardia or ventricular fibrillation (VF) during device safety testing of an implantable cardioverter defibrillator implantation or battery replacement, were compared with 15 patients, who during a tilt-table test were diagnosed with vasovagal syncope (VS). For each patient, a blood sample for NT-proBNP evaluation was collected at baseline and 6 hours after the episode of ventricular tachycardia, VF, or VS. We calculated the percentage of increase in the 6-hour NT-proBNP concentration between the 2 groups using nonparametric techniques. We also calculated the area under a receiver operating characteristic curve with the 95% confidence intervals. The 6-hour change in the NT-proBNP concentrations between patients who had had an episode of ventricular tachycardia or VF and patients with VS was significantly different, with a median increase of 32% in the ventricular tachycardia or VF group versus 5% in the VS group (p <0.01). The area under a receiver operating characteristic curve to predict arrhythmic syncope was 0.8 (95% confidence interval 0.65 to 0.95). In conclusion, the results of the present study suggest that a 6-hour NT-proBNP increase might be able to predict arrhythmic syncope. Future work is needed to confirm these findings in undifferentiated emergency department patients who present with syncope.

STUDY OBJECTIVES:There is limited evidence to guide the emergency department (ED) evaluation and management of syncope. The First International Workshop on Syncope Risk Stratification in the Emergency Department identified key research questions and methodological standards essential to advancing the science of ED-based syncope research.METHODS:We recruited a multinational panel of syncope experts. A preconference survey identified research priorities, which were refined during and after the conference through an iterative review process.RESULTS:There were 31 participants from 7 countries who represented 10 clinical and methodological specialties. High-priority research recommendations were organized around a conceptual model of ED decisionmaking for syncope, and they address definition, cohort selection, risk stratification, and management.CONCLUSION:We convened a multispecialty group of syncope experts to identify the most pressing knowledge gaps and defined a high-priority research agenda to improve the care of patients with syncope in the ED.

Background There have been several attempts to derive syncope prediction tools to guide clinician decision-making. However, they have not been largely adopted, possibly because of their lack of sensitivity and specificity. We sought to externally validate the existing tools and to compare them with clinical judgment, using an individual patient data meta-analysis approach. Methods Electronic databases, bibliographies, and experts in the field were screened to find all prospective studies enrolling consecutive subjects presenting with syncope to the emergency department. Prediction tools and clinical judgment were applied to all patients in each dataset. Serious outcomes and death were considered separately during emergency department stay and at 10 and 30 days after presenting syncope. Pooled sensitivities, specificities, likelihood ratios, and diagnostic odds ratios, with 95% confidence intervals, were calculated. Results Thirteen potentially relevant papers were retrieved (11 authors). Six authors agreed to share individual patient data. In total, 3681 patients were included. Three prediction tools (Osservatorio Epidemiologico sulla Sincope del Lazio [OESIL], San Francisco Syncope Rule [SFSR], Evaluation of Guidelines in Syncope Study [EGSYS]) could be assessed by the available datasets. None of the evaluated prediction tools performed better than clinical judgment in identifying serious outcomes during emergency department stay, and at 10 and 30 days after syncope. Conclusions Despite the use of an individual patient data approach to reduce heterogeneity among studies, a large variability was still present. Current prediction tools did not show better sensitivity, specificity, or prognostic yield compared with clinical judgment in predicting short-term serious outcome after syncope. Our systematic review strengthens the evidence that current prediction tools should not be strictly used in clinical practice.

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract-associated hospitalizations in children under the age of 2. Acute RSV infection induces both Th1- and Th2-associated responses, with elevated airway hyperactivity being highly correlated with increased Th2-associated responses. However, the mechanism for induction of Th1 vs. Th2-associated responses following RSV infection is currently unknown. The inhibitory ligands PD-L1 and PD-L2 serve a critical role in the induction and regulation of Th1 and Th2-associated responses, respectively, during acute infections as well as asthma. Following acute RSV infection, lung epithelial cells upregulate PD-L1 within 24 hours post-infection (p.i.) with peak expression occurring at day 6 p.i.. Furthermore, both lung and mediastinal lymph node (MedLN) CD11c+ cDCs and pDCs upregulate PD-L1 expression early following RSV infection and retain increased PD-L1 expression throughout the course of infection. In contrast, PD-L2 expression is primarily restricted to CD11c+ cDCs. PD-L2 expression peaks at day 6 p.i. on both lung and MedLN CD11c+ cDCs, correlating with increased airway resistance following acute RSV infection. PD-L2-blockade early during RSV infection results in increased airway hyperactivity, whereas PD-L1-blockade exhibited no significant effect. These data suggest that PD-L2 plays a critical role in the regulation of RSV-induced immunopathology.

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.

Objective: The aim of this study was to determine the rate of infection at which it is cost-effective to treat dog bite wounds with antibiotics.Methods: Our study was composed of two parts. First we performed a randomized, doubleblind controlled trial (RCT) to compare the infection rates of dog bite wounds in patients given amoxicillin-clavulanic acid versus placebo. Subjects were immunocompetent patients presenting to the emergency department (ED) with dog bite wounds less than 12 hours old without suspected neurovascular, tendon, joint or bone injury, and who had structured follow-up after two weeks. Second, we developed a cost model with sensitivity analysis to determine thresholds for treatment.Results: In the RCT, primary outcomes were obtained in 94 patients with dog bites. The overall wound infection rate at two weeks was 2% [95% CI 0 to 7%]. Two of 46 patients (4%) receiving no antibiotics developed infections, while none of the 48 patients (0%) receiving prophylactic antibiotics developed an infection (absolute reduction 4% [95% CI -1.0 to 4.5%]). Using a sensitivity analysis across a rate of infections from 0-10%, our cost model determined that prophylactic antibiotics were cost effective if the risk of wound infection was greater than 5% and antibiotics could decrease that risk by greater than 3%.Conclusion: Our wound infection rate was lower than older studies and more in line with current estimates. Assuming that prophylactic antibiotics could provide an absolute risk reduction (ARR) of 3%, it would not be cost effective to treat wounds with an infection rate of less than 3% and unlikely that the ARR would be achievable unless the baseline rate was greater than 5%, suggesting that only wounds with greater than 5% risk of infection should be treated. Future work should focus on identifying wounds at high-risk of infection that would benefit from antibiotic prophylaxis.

CD4 T cells play a vital role in orchestrating adaptive immune responses. Measuring the magnitude of the CD4 T cell response to a given pathogen is currently hindered by the lack of complete knowledge of all of the CD4 T cell epitopes. In cases where most or all of the CD4 T cell epitopes have been mapped, current estimates based on intracellular cytokine production for cytokines such as IFN-γ may also under-represent the frequency of antigen-specific CD4 T cells because of the high heterogeneity in cytokine production exhibited by differentiated effector CD4 T cells. Here we show that following lymphocytic choriomeningitis virus (LCMV) infection, T cell receptor-transgenic CD4 T cells specific to LCMV upregulate CD11a and CD49d and that expression of these adhesion molecules remains stable into memory. Expression of these integrins requires cognate antigen and is not modulated non-specifically by inflammatory signals such as stimulation with LPS or CPG. Additionally, CD11a and CD49d expression is upregulated on endogenous CD4 T cells following acute LCMV infection as well as all LCMV-specific CD4 T cells that respond to previously identified CD4 T cell epitopes. Using these markers we estimate the total magnitude of the virus-specific CD4 T cell response to multiple pathogens and our results indicate that the CD4 T cell response is substantially larger than previously thought.

OBJECTIVE We sought to determine the incidence of acute myocardial infarction (AMI) in emergency department (ED) patients with syncope, the characteristics of these AMIs and how helpful the initial electrocardiogram (ECG) was in identifying these cases. METHODS In a prospective cohort of consecutive patients with syncope, the initial ECG was found to be abnormal using a prespecified definition (any nonsinus rhythm or any new or age- indeterminate abnormalities). Patients were then followed up to identify an AMI diagnosed within 30 days of presentation. RESULTS There were 1474 consecutive patient visits for syncope or near-syncope over a 45-month period spanning from Jul. 1, 2000, to Feb. 28, 2002, and Jul. 15, 2002, to Aug. 31, 2004, of which 46 (3.1%) were diagnosed with AMI. The majority of the AMI patients (42) had no ST segment elevation. The initial ECG was abnormal in 37 out of 46 cases. The diagnostic performance of the initial ECG was sensitivity 80% (95% confidence interval [CI] 67%-89%), specificity 64% (95% CI 61%-67%), negative predictive value 99% (95% CI 98%-100%), positive predictive value 7% (95% CI 6%-8%), positive likelihood ratio 2.2 (95% CI 1.6-2.5) and negative likelihood ratio 0.3 (95% CI 0.2-0.5). CONCLUSION The incidence of AMI in patients presenting with syncope is low. A normal ECG has a high negative predictive value, although its sensitivity is limited.

STUDY OBJECTIVE:To determine the accuracy of the online Social Security Death Index (SSDI) for determining death outcomes.METHODS:We selected 30 patients who were determined to be dead and 90 patients thought to be alive after an ED visit as determined by a web-based searched of the SSDI. For those thought to be dead we requested death certificates. We then had a research coordinator blinded to the results of the SSDI search, complete direct follow-up by contacting the patients, family or primary care physicians to determine vital status. To determine the sensitivity and specificity of the SSDI for death at six months in this cohort, we used direct follow-up as the criterion reference and calculated 95% confidence intervals.RESULTS:Direct follow-up was completed for 90% (108 of 120) of the patients. For those patients 20 were determined to be dead and 88 alive. The dead were more likely to be male (57%) and older [(mean age 83.9 (95% CI 79.1 - 88.7) vs. 60.9 (95% CI 56.4 - 65.4) for those alive]. The sensitivity of the SSDI for those with completed direct follow-up was 100% (95% CI 91 -100%) with specificity of 100% (95% CI 98-100%). Of the 12 patients who were not able to be contacted through direct follow-up, the SSDI indicated that 10 were dead and two were alive.CONCLUSIONS:SSDI is an accurate measure of death outcomes and appears to have the advantage of finding deaths among patients lost to follow-up.

Study objective: We seek to compare ultrasonographically guided peripheral intravenous access to a non-ultrasonographically guided method in a randomized trial of emergency department patients with difficult intravenous access.Methods: A prospective cohort of patients with difficult intravenous access was established. Patients were randomized to 2 groups: (1) intravenous access obtained through an ultrasonographically guided technique or (2) intravenous access obtained through non-ultrasonographically guided methods. Outcomes measured were number of attempts after enrollment, time to cannulation from enrollment, and patient satisfaction. Groups were compared with nonparametric analysis.Results: Fifty-nine patients were randomized. Twenty-eight patients were randomized to the ultrasonography group and 31 to the no ultrasonography group. A median of 2 further intravenous attempts was required in each group before successful cannulation, corresponding to a difference of 0 attempts (95% confidence interval [CI] 0 to 1 attempts). Time to cannulation showed a median of 39 minutes in the ultrasonography group compared with 26 minutes for the no ultrasonography group, giving a median increase of 13 minutes for the ultrasonographically guided group (95% CI -5 to 28 minutes). Patients in the ultrasonography group had a median Likert satisfaction score of 8 compared with 7 for the no ultrasonography group, giving a median increase of 1 on this scale in the ultrasonography group (95% CI 0 to 2).Conclusion: Ultrasonographically guided peripheral intravenous cannulation did not decrease the number of attempts or the time to successful catheterization, nor did it improve patient satisfaction compared with the group that did not use ultrasonography. Superiority of ultrasonographically guided peripheral intravenous cannulation is not supported by this study. [Ann Emerg Med. 2009;54:33-40.]

SAEM W estern R egional A bstracts vital signs, GCS, patient disposition from ED and final clinical outcome. Logistic regression and chi-square statistics were applied to compare mortality rates between the two groups. Results: A total of 94 IFT and 379 DT cases were studied. Cases were matched according to GCS. The median time for direct transport was 26 minutes while the median time of IFT was 151 minutes. A total of 77.7% of all patients arriving by IFT survived to discharge compared with 71.2% of DT patients (p=0.21). The odds ratio for survival (IFT/DT) was 1.40. The logistical regression demonstrated a small but statistically insignificant contribution to survival for each additional stabilization minute for patients from an IFT. Conclusions: Direct transport to a neurosurgical-capable trauma center from the scene for patients with GCS less than 8 does not confer a survival benefit when compared with patients taken to the nearest hospital before IFT. We recommend that pre-hospital triage guidelines include provisions for initial stabilization at a Level III center in lieu of mandatory transport to the regional Level I trauma center. antibiotic group 0% (95% CI 0-6%) and 2 in the placebo 4.5% (95%CI 1-15%). Both infected wounds were sutured and on the face. The cost model determined antibiotics would always be cost effective when the infection rate was greater than 5% and never be cost effective if the rate was 12 hours old and those with suspected neurovascular, tendon, joint or bone injury. Patients were randomized to treatment, and structured follow-up was done after 14 days to determine the presence of a wound infection. Continuous data were compared with t-test and categorical data with chi square analysis. Data generated with 95%CI were then used in a cost model and a sensitivity analysis done to determine thresholds for treatment. Results: We considered 230 consecutive dog bites, 146 were eligible, 6 were missed, 33 refused, and 97 consented to participate. Seventy-two percent were non facial, 62% were full thickness and 14% were sutured. There were no differences in demographic or clinical characteristics between the groups. Overall infection rate was 2% (95% CI 0-7%), none in the Volume VIII, no . 3 : August 2007 Objectives: Ski helmets reduce the risk of brain injury, but helmet use is low. Ski patrollers (SPs) could serve as role models for helmet use, but little is known about their practices and beliefs. We studied: The frequency of helmet use by SPs; reasons for non-use; and beliefs predictive of helmet use. Methods: A survey was completed by a convenience sample of SPs attending conferences. Questions addressed helmet use, head injury experience (self, family, friends) and knowledge of helmets and injury risk reduction. Helmet use was defined as “100% use during patrol skiing.” To assess predictors of helmet use, odds ratios and 95% confidence intervals were calculated, after adjusting for seasons skied. Results: Among 93 SPs, most were men (79%), < 45 years old (70%) and experienced (mean seasons skied = 26 ± 11). Helmet use was 21% (CI95 = 14-31). Common reasons for non-use were hearing (35%), comfort (28%) and vision (24%); only 16% cited “socially unacceptable.” Most SPs believed helmets prevent injuries (90%) and that SPs are role models (93%). Head injury experience was common (23%). However, many SPs believed helmets encourage reckless skiing (39%) and increase injury risks (16%). Four factors predicted helmet use: head injury experience (9.8; 1.02-94); perceived exposure protection (OR = 9.7; CI95 = 3.1-29.8); belief that role modeling is an advantage of helmets (3.5; 1.1-10.6); and belief that helmets encourage reckless skiing (.17; .03-.83). Conclusions: Although based on self-reports by a small convenience sample of SPs, these data suggest there is discordance: SPs are convinced that helmets reduce serious injury and that they are role models, but most do not wear helmets regularly. Manufacturers should address helmet design and comfort. Education programs should include head injury cases, address the belief that helmets encourage recklessness (risk homeostasis) and stress role modeling as a professional responsibility. Western Journal of Emergency Medicine Ski Patrollers: Reluctant Role Models for Helmet Use Bruce Evans, MD; Jack Thomas Gervais; Laura Sehnert, MD; Morgan Valley, MS; Steven Lowenstein, MD, MPH. University of Colorado Health Sciences Center

STUDY OBJECTIVE:Syncope is a common condition that is usually benign but occasionally associated with death. This study evaluates the incidence of death after an emergency department (ED) visit for syncope and whether these deaths can be predicted.METHODS:A prospective cohort study was conducted during a 45-month period. All patients were followed up 1-and-a-half years after their initial ED visit to determine whether they had died. Death certificates were independently reviewed by 2 physicians for the cause and date of death to determine whether the death was possibly related to the initial visit for syncope. Sensitivity and specificity of risk factors (defined by the San Francisco Syncope Rule) or age greater than 65 years was calculated for all-cause mortality and mortality thought possibly related to syncope.RESULTS:There were 1418 consecutive patients with syncope during the study period, representing 1.2% of all ED visits. The all-cause death rate was 1.4% at 30 days, 4.3% at 6 months, and 7.6% at 1 year. It was believed that the death rates from causes possibly related to syncope were 2.3% and 3.8% at 6 months and 1 year. Of the 112 deaths at 1 year, 37% were cardiac related. At 6 months, the risk factors had a sensitivity of 89% (95% confidence interval [CI] 79% to 95%) and specificity of 53% (95% CI 52% to 53%) for all-cause mortality and sensitivity of 100% (95% CI 90% to 100%) and specificity 52% (95% CI 52% to 53%) for predicting deaths likely or possibly related to syncope. Age greater than 65 years had similar sensitivity but much worse specificity compared with the set combined risk factors.CONCLUSION:Deaths related to syncope after an ED visit are low, especially in the first 6 months and can usually be predicted by risk factors.

STUDY OBJECTIVEWe prospectively validate the San Francisco Syncope Rule (history of congestive heart failure, Hematocrit <30%, abnormal ECG result [new changes or non-sinus rhythm], complaint of shortness of breath, and systolic blood pressure <90 mm Hg during triage).METHODSIn a prospective cohort study, consecutive patients with syncope or near syncope presenting to an emergency department (ED) of a teaching hospital were identified and enrolled from July 15, 2002, to August 31, 2004. Patients with trauma, alcohol, or drug-associated loss of consciousness and definite seizures were excluded. Physicians prospectively applied the San Francisco Syncope Rule after their evaluation, and patients were followed up to determine whether they had had a predefined serious outcome within 30 days of their ED visit.RESULTSSeven hundred ninety-one consecutive visits were evaluated for syncope, representing 1.2% of all ED visits. The average age was 61 years, 54% of patients were women, and 59% of patients were admitted. Fifty-three visits (6.7%) resulted in patients having serious outcomes that were undeclared during their ED visit. The rule was 98% sensitive (95% confidence interval [CI] 89% to 100%) and 56% specific (95% CI 52% to 60%) to predict these events. In this cohort, the San Francisco Syncope Rule classified 52% of the patients as high risk, potentially decreasing overall admissions by 7%. If the rule had been applied only to the 453 patients admitted, it might have decreased admissions by 24%.CONCLUSIONThe San Francisco Syncope Rule performed with high sensitivity and specificity in this validation cohort and is a valuable tool to help risk stratify patients. It may help with physician decisionmaking and improve the use of hospital admission for syncope.