Accurate prediction of survival to hospital discharge in patients who achieve return of spontaneous circulation after cardiopulmonary resuscitation (CPR) has significant ethical and socioeconomic implications. We investigated the prognostic performance of serum neuron-specific enolase (NSE), a biochemical marker of ischemic brain injury, after successful CPR.

In-hospital or out-of-hospital patients with nontraumatic normothermic cardiac arrest who achieved return of spontaneous circulation (ROSC) following at least 5 minutes of CPR were eligible. Neuron-specific enolase levels were assessed immediately, 6 hours, 12 hours and 2 days after ROSC. Subjects were followed to death or hospital discharge.

Seventeen patients (7 men, 10 women) were enrolled during a 1-year period. Median (range) NSE levels in survivors and non-survivors respectively were as follows: immediately after ROSC: 14.0 μg/L (9.1–51.4 μg/L) versus 25.9 μg/L (10.2–57.5 μg/L); 6 hours after ROSC: 15.2 μg/L (9.7–30.8 μg/L) versus 25.6 μg/L (12.7–38.2 μg/L); 12 hours after ROSC: 14.0 μg/L (8.6–32.4 μg/L) versus 28.5 μg/L (11.0–50.7 μg/L); and 48 hours after ROSC: 13.1 μg/L (7.8–29.5 μg/L) versus 52.0 μg/L (29.1–254.0 μg/L). Non-survivors had significantly higher NSE levels 48 hours after ROSC than surivors (p = 0.04) and showed a trend toward higher values during the entire time course following ROSC. An NSE concentration of >30 μg/L 48 hours after ROSC predicted death with a high specificity (100%: 95% confidence interval [CI] 85%–100%), and a level of 29 μg/L or less at 48 hours predicted survival with a high specificity (100%: 95% CI 83%–100%).

Serum NSE levels may have clinical utility for the prediction of survival to hospital discharge in patients after ROSC following CPR over 5 minutes in duration. This study is small, and our results are limited by wide confidence intervals. Further research on ability of NSE to facilitate prediction and clinical decision-making after cardiac arrest is warranted.

Using a simulated airway model, we compared ventilation performance by emergency medical services (EMS) providers using a traditional bag–valve–mask (Easy Grip®) resuscitator to their performance when using a new device, the SMART BAG® resuscitator, which has a pressure-responsive flow-limiting valve.

We recruited EMS providers at an EMS educational forum and performed a randomized, non-blinded, prospective crossover comparison of ventilation with 2 devices on a non-intubated simulated airway model. Subjects were instructed to ventilate a Mini Ventilation Training Analyzer® as they would an 85-kg adult patient in respiratory arrest. After being randomized to order of device use, they performed ventilation for 1 minute with each device. Primary outcomes were ventilation rates and peak airway pressures. We also measured average tidal volume, gastric inflation volume, minute ventilation and inspiratory:expiratory (I:E) ratio, and compared our results to the American Heart Association standards (2005 edition).

We observed statistically significant differences between the SMART BAG® and the traditional bag–valve–mask for respiratory rate (12 v. 14 breaths/min), peak airway pressure (15.6 v. 18.9 cm H2O), gastric inflation (239.6 v. 1598.4 mL), minute ventilation (7980 v. 8775 mL), and I:E ratio (1.3 v. 1.1). Average tidal volume was similar with both devices (679.6 v. 672.2 mL).

The SMART BAG® provided ventilation performance that was more consistent with American Heart Association guidelines and delivered similar tidal volumes when compared with ventilation with a traditional bag–valve–mask resuscitator.

Many emergency department (ED) visits are non-urgent. Postulated reasons for these visits include lack of access to family physicians, convenience and 24/7 access, perceived need for investigations or treatment not available elsewhere, and as a mechanism for expedited referral to other specialists. We conducted a patient survey to determine why non-urgent patients use our tertiary care ED. Our primary objective was to determine how often the lack of a family physician was associated with non-urgent ED use.

The survey was administered to Canadian Emergency Department Triage and Acuity Scale (CTAS) Level IV and V patients who attended the ED of the Queen Elizabeth II Health Sciences Centre in Halifax, NS, from March 7 to March 13, 2005.

Of the 352 eligible patients, 235 completed the survey (response rate, 67%). Fifty-six percent (132/235) had an acute medical problem of less than 48 hours, including 48% (114/235) with a recent injury. Thirty-four percent (82/235) had been referred to the ED, 49% (114/235) believed they required a specific service that was unavailable elsewhere (e.g., radiology, suturing, casting) and 43% (100/235) presented because of self-perceived urgency of their condition. Eighty-four percent (198/235) had a family physician; 23% (55/235) used the ED because of limited access to theirfamily physician and 3% (6/235) used the ED because they did not have a family physician.

In this setting, most non-urgent ED visits involved patients who required a specific service offered by the ED, patients who believed their condition was urgent, or patients who were referred from the community to the ED. From a patient perspective, relatively few visits would be considered inappropriate. Lack of a family physician was not associated with non-urgent ED use; however, inability to obtain timely access to the FP was a factor in one-quarter of cases.

It is often believed that chest pain relieved by nitroglycerin is indicative of coronary artery disease origin.

To determine if relief of chest pain with nitroglycerin can be used as a diagnostic test to help differentiate cardiac chest pain and non-cardiac chest pain.

Prospective observational cohort study with a 4-week follow-up of patients enrolled.

Academic tertiary care hospital, with 60 000 visits/year.

Adult patients presenting to the emergency department with active chest pain who received nitroglycerin and were admitted for chest pain.

Patients with acute myocardial infarction diagnosed after obtaining an ECG, patients whose chest pain could not be quantified, those for whom no cardiac work-up was done, or those who received emergent cardiac catheterization.

270 patients were enrolled. Nitroglycerin relieved chest pain in 66% of the subjects. The diagnostic sensitivity of nitroglycerin to determine cardiac chest pain was 72% (64%–80%), and the specificity was 37% (34%–41%). The positive likelihood ratio for having coronary artery disease if nitroglycerin relieved chest pain was 1.1 (0.96–1.34). Telephone follow-up at 4 weeks was performed, with a 95% follow-up rate.

Relief of chest pain with nitroglycerin is not a reliable diagnostic test and does not distinguish between cardiac and non-cardiac chest pain.

To evaluate whether the addition of intravenous (IV) dexamethasone to standard emergency department (ED) benign headache therapy would reduce the incidence of headache recurrence at 48–72 hours.

This randomized, double-blind, placebo-controlled clinical trial of adult patients presenting with the chief complaint of headache was conducted in the ED of 2 academic, urban Level 1 hospitals. Headache evaluation and therapy were determined by the treating physician, and, before discharge, patients were administered either 10 mg of IV dexamethasone or placebo. The treatment groups had similar baseline characteristics, abortive therapy, IV fluids and degree of pain relief achieved before discharge. Patients were contacted 48–72 hours following discharge and asked whether their headache was “better,” “worse” or “remained unchanged” when compared with their symptoms at discharge. Those whose headaches were “worse” or “unchanged,” and those who reported a return of headache after being pain free at discharge were considered to be treatment failures and classified as having had a recurrence. The patient's headache at follow-up was further categorized as severe (i.e., provoking another physician visit or interfering with daily activity) or mild (i.e., requiring self-medication or no treatment).

Fifty-seven patients met the inclusion criteria and 2 were lost to follow-up, leaving 55 for analysis. At follow-up, 9.7% (3/31) of those receiving dexamethasone had headache recurrence, versus 58.3% (14/24) of those receiving placebo (p < 0.001). Four dexamethasone recipients (12.9%) had severe headaches at follow-up compared with 8 (33.3%) in the placebo group (p = 0.14).

In this study, IV dexamethasone reduced headache recurrence at 48–72-hour follow-up. Given its excellent safety profile and likely benefit, IV dexamethasone should be considered for ED headache patients after standard evaluation and therapy.

Most studies of pre-hospital management of ST-elevation myocardial infarction (STEMI) have involved physicians accompanying the ambulance crew, or electrocardiogram (ECG) transmission to a physician at the base hospital. We sought to determine if Advanced Care Paramedics (ACPs) could accurately identify STEMI on the pre-hospital ECG and contribute to strategies that shorten time to reperfusion.

A STEMI tool was developed to: 1) measure the accuracy of the ACPs at diagnosing STEMI; and 2) determine the potential time saved if ACPs were to independently administer thrombolytic therapy. Using registry data, we subsequently estimated the time saved by initiating thrombolytic therapy in the field compared with in-hospital administration by a physician.

Between August 2003 and July 2004, a correct diagnosis of STEMI on the pre-hospital ECG was confirmed in 63 patients. The performance of the ACPs in identifying STEMI on the ECG resulted in a sensitivity of 95% (95% confidence interval [CI] 86%–99%), a specificity of 96% (95% CI 94%–98%), a positive predictive value (PPV) of 82% (95% CI 71%–90%), and a negative predictive value (NPV) of 99% (95% CI 97%–100%). ACP performance for appropriately using thrombolytic therapy resulted in a sensitivity of 92% (95% CI 78%–98%), a specificity of 97% (95% CI 94%–98%), a PPV of 73% (95% CI 59%–85%) and an NPV of 99% (95% CI 97%–100%). We estimated that the median time saved by ACP administration of thrombolytic therapy would have been 44 minutes.

ACPs can be trained to accurately interpret the pre-hospital ECG for the diagnosis of STEMI. These results are important for the design of regional integrated programs aimed at reducing delays to reperfusion.

In 2004, the format of the Royal College of Physicians and Surgeons of Canada certification exam in Emergency Medicine was modified to include an audiovisual session. Residents' performance on such stimuli is unknown. This study aims to determine the performance of Emergency Medicine postgraduate year 5 (PGY-5) on a novel practice examination using visual stimuli, in an effort to guide residents' preparatory study, and to help educators focus the teaching related to visual stimuli.

In this prospective observational study, 30 PGY-5 residents from 12 Emergency Medicine programs across Canada participated in a practice examination in which they had to answer 133 questions related to 80 visual stimuli. The stimuli included electrocardiograms, medical imaging and clinical photographs. Three experienced faculty provided “reference standard” answers for the visual stimuli. For analysis purpose, stimuli were classified into 9 clinical domains, outlined in The Model of the Clinical Practice of Emergency Medicine.

Insufficient question numbers in 3 domains prevented reliable inferences. Correct answers were given for 65% of remaining questions, with the following domain distribution: 69% respiratory, 64% trauma, 73% cardiovascular, 62% head–eyes–ears–nose–throat (HEENT), 63% musculoskeletal and 69% cutaneous. Seventy-four percent of ECGs, 64% of imaging, and 62% of photograph-related questions were answered correctly. Incorrect answers were related to a lack of knowledge as well as imprecise or incomplete responses.

PGY-5 subjects scored lowest in the HEENT and musculoskeletal domains. Medical educators should emphasize these domains in their teaching, and insist on precision and completeness of answers.

To assess the safety and effectiveness of intravenous regional anesthesia (Bier block) in the management of forearm injuries (i.e., forearm, wrist or hand) by primary care physicians at a diagnostic and treatment facility.

A retrospective review was conducted of all patients at a single centre who underwent a Bier block for forearm injuries between September 2000 and March 2005.

1816 Bier blocks were performed on 1804 patients (64% male) during the study period. Patient age ranged from 4–70 (mean 25) years. Wrist fractures requiring reduction were the most common diagnosis. Adverse events were recorded in 9 cases (0.50%, 95% confidence interval 0.23%–0.94%): 1 case of medication error (0.06%); 3 of improper cuff inflation (0.17%); and 5 of inadequate analgesia (0.28%). None of the adverse events resulted in failure to complete the procedure or in serious morbidity or mortality.

Bier block anesthesia is a safe, effective and reliable technique in an outpatient primary care setting. This technique is a useful modality for physicians who manage acute upper-extremity injuries.

To examine the effect of severe acute respiratory syndrome (SARS) on visits to a community hospital emergency department (ED) during the early stage of the Toronto outbreak in 2003 and for the same period in 2004. We focused on visits for respiratory illness (SARS-like symptoms) and different age groups.

This study is a retrospective review of ED discharge diagnoses obtained from a computerized database, examining the 4-week period starting March 28 for the years 2001-2004. We obtained the discharge diagnosis, age and visit date for each ED patient during the relevant time intervals, then compared visit data from 2003 and 2004 with a baseline derived from the average number of visits during 2001 and 2002. We constructed groupings based on age and respiratory-illness symptoms.

During the SARS outbreak in 2003, ED visits declined by 21% (95% confidence interval [CI], 18%–24%) over the 4-week study period. The greatest reduction was for combined infant and toddler visits (69%; 95% CI, 58%–79%); these did not recover the following year. However, during the SARS outbreak there was a large increase in the number of visits for respiratory illnesses in adults (61%; 95% CI, 46%–75%) and in teenagers (132%; 95% CI, 82%–182%).

During the SARS outbreak, total ED visits fell. The relative decline was most notable for infants and toddlers. By contrast, there was an increase in respiratory illness–related visits for adults and teenagers. In 2004, the year following the SARS outbreak, visit patterns shifted toward baseline levels, but ED visits by infants and toddlers remained depressed.