Diagnosing pulmonary embolism can be difficult given its highly variable clinical presentation. Our objective was to determine whether a decrease in oxygen saturation or an increase in heart rate while ambulating could be used as an objective tool in the diagnosis of pulmonary embolism.

This was a two-site tertiary-care-centre prospective cohort study that enrolled adult emergency department or thrombosis clinic patients with suspected or newly confirmed pulmonary embolism. Patients were asked to participate in a standardized 3-minute walk test, which assessed ambulatory heart rate and ambulatory oxygen saturation. The primary outcome was pulmonary embolism.

We enrolled 114 patients, including 30 with pulmonary embolism (26.3%). A ≥2% absolute decrease in ambulatory oxygen saturation and an ambulatory change in heart rate >10 beats per minute (BPM) were significantly associated with pulmonary embolism. An ambulatory heart rate change of >10 BPM had a sensitivity of 96.6% (95% confidence interval [CI] 83.3 to 99.4) and a specificity of 31.0% (95% CI 22.1 to 45.0) for pulmonary embolism. A ≥2% absolute decrease ambulatory oxygen saturation had a sensitivity of 80.2% (95% CI 62.7 to 90.5) and a specificity of 39.3% (95% CI 29.5 to 50.0) for pulmonary embolism. The combination of both variables yielded a sensitivity of 100.0% (95% CI 87.0 to 100.0) and a specificity of 11.0% (95% CI 6.6 to 21.0).

In summary, our study found that an ambulatory heart rate change of >10 BPM or a ≥2% absolute decrease in ambulatory oxygen saturation from baseline during a standardized 3-minute walk test are highly correlated with pulmonary embolism. Although the findings appear promising, neither of these variables can currently be recommended as a screening tool for pulmonary embolism until larger prospective studies examine their performance either alone or with pre-existing rules.

Not all patients with suspected acute coronary syndrome (ACS) receiving cardiac troponin (cTn) testing present to the emergency department (ED) with cardiac chest pain. Since elderly patients (age ≥70) have increased morbidity and mortality associated with ACS, complaints other than cardiac chest pain may justify cTn testing. Our primary objective was to characterize the population of ED patients who receive cTn testing. The secondary objective was to determine if elderly patients underwent cTn testing for different presenting complaints than their younger counterparts.

We created an electronic database including Canadian Emergency Department Information Systems (CEDIS) presenting complaints, age, sex, disposition, and Canadian Triage Acuity Scale (CTAS) score, for patients who received cTn testing in three Canadian EDs during 2011. We analyzed the data for patient characteristics and sorted by age (<70 and ≥70) for further analysis.

In the 15,824 included patients, the average age was 66 (51%<70; 51% female). The most common presenting complaints were cardiac chest pain (n=3,267) and shortness of breath (n=2,266). The elderly underwent cTn testing for significantly (p<0.0001) different complaints than their younger counterparts. They more commonly presented with generalized weakness (n=898), whereas younger patients more frequently had abdominal pain (n=576).

Cardiac chest pain and shortness of breath are presenting complaints in one-third of patients undergoing ED cTn testing. The majority of patients undergoing cTn testing did not have typical ACS symptoms. Half of all cTn testing in the ED is on the elderly, who present with different complaints than their younger counterparts.

Unenhanced computed tomography (CT) has become a standard imaging technique for uncomplicated renal colic in many countries. The appropriate timing of CT imaging has not been established, and guidelines recommend that this imaging be performed between 1 and 7 days of presentation. The primary objective of this study was to determine the prevalence of alternative diagnosis identified with low-dose unenhanced CT in the emergency department (ED) in patients with suspected uncomplicated renal colic.

This prospective single-centre study was carried out in a large university hospital ED. Over a 6-month period, all patients with clinically diagnosed renal colic and a plan to be discharged underwent low-dose unenhanced CT in the ED. Pregnant women, women of childbearing age not willing to have a pregnancy test, and patients who had already undergone diagnostic imaging were excluded. The primary outcome was the number and nature of the alternative diagnosis. Univariate analyses were performed to assess factors associated with the primary outcome.

A total of 178 patients were screened, and 155 underwent CT in the ED. The mean age was 42.2 years; 69% were male. The diagnosis of uncomplicated renal colic was confirmed in 118 participants (76%); 27 (17%) had an inconclusive CT scan. Overall, 10 patients (6%; 95% confidence interval [CI] 3–10) had an alternative diagnosis, 5 of whom were subsequently hospitalized.

Low-dose unenhanced CT in the ED detects alternative diagnoses in 6% (95% CI 3–10) of patients with suspected uncomplicated renal colic, half of whom are subsequently hospitalized. Our prospective findings, which were similar to those reported in retrospective studies, are a potential argument for a systematic approach to ED imaging in suspected renal colic. Future research involving intervention and control groups would be helpful.

To perform a review and meta-analysis on the effect of antibiotics on treatment of skin and soft tissue abscesses (SSTAs) after incision and drainage.

We searched MEDLINE, EMBASE, Web of Knowledge, and Google Scholar databases to identify randomized controlled trials (RCTs) and observational studies. For RCTs, we included studies comparing any antibiotic (treatment) to placebo (control). For observational studies, treatment was the use of appropriate antibiotics effective against bacterial isolate, and control was the use of inappropriate (ineffective) or no antibiotics. Outcome was treatment success during follow-up. Two investigators reviewed records, assessed quality (according to Cochrane and Newcastle-Ottawa tools), and extracted treatment success rates. Primary analysis was the effect of treatment among RCTs. Secondary analyses included the effect of treatment in 1) observational studies of confirmed methicillin-resistant Staphylococcus aureus (MRSA) infection (MRSA-only) and 2) all studies after 1998 (MRSA-era). We used random effects modelling, except when no heterogeneity was present when we used fixed effects.

We screened 1,968 records. Twelve were included (five RCTs, seven observational studies), representing 1,969 subjects. Seven enrolled from emergency departments, two from surgical clinics, and three from ambulatory clinics. Three enrolled children only. Pooled relative risk (RR) of treatment success among RCTs was 1.03 (95% confidence interval [CI] 0.97−1.08). Pooled RR in the secondary analyses was 1.05 (95% CI 0.96−1.15) in MRSA-only and 0.99 (95% CI 0.98−1.01) in MRSA-era.

Despite limitations in pooling available data, there is no clear evidence to support antibiotic use in treating uncomplicated SSTAs.

Offload delay is a prolonged interval between ambulance arrival in the emergency department (ED) and transfer of patient care, typically occurring when EDs are crowded. The offload zone (OZ), which manages ambulance patients waiting for an ED bed, has been implemented to mitigate the impact of ED crowding on ambulance availability. Little is known about the safety or efficiency. The study objectives were to process map the OZ and conduct a hazard analysis to identify steps that could compromise patient safety or process efficiency.

A Health Care Failure Mode and Effect Analysis was conducted. Failure modes (FM) were identified. For each FM, a probability to occur and severity of impact on patient safety and process efficiency was determined, and a hazard score (probability X severity) was calculated. For any hazard score considered high risk, root causes were identified, and mitigations were sought.

The OZ consists of six major processes: 1) patient transported by ambulance, 2) arrival to the ED, 3) transfer of patient care, 4) patient assessment in OZ, 5) patient care in OZ, and 6) patient transfer out of OZ; 78 FM were identified, of which 28 (35.9%) were deemed high risk and classified as impact on patient safety (n=7/28, 25.0%), process efficiency (n=10/28, 35.7%), or both (n=11/28, 39.3%). Seventeen mitigations were suggested.

This process map and hazard analysis is a first step in understanding the safety and efficiency of the OZ. The results from this study will inform current policy and practice, and future work to reduce offload delay.

Emergency medicine point-of-care ultrasonography (EM-PoCUS) is a core competency for residents in the Royal College of Physicians and Surgeons of Canada and College of Family Physicians of Canada emergency medicine (EM) training programs. Although EM-PoCUS fellowships are currently offered in Canada, there is little consensus regarding what training should be included in a Canadian EM-PoCUS fellowship curriculum or how this contrasts with the training received in an EM residency.

To conduct a systematic needs assessment of major stakeholders to define the essential elements necessary for a Canadian EM-PoCUS fellowship training curriculum.

We carried out a national survey of experts in EM-PoCUS, EM residency program directors, and EM residents. Respondents were asked to identify competencies deemed either nonessential to EM practice, essential for general EM practice, essential for advanced EM practice, or essential for EM-PoCUS fellowship trained (‘‘expert’’) practice.

The response rate was 81% (351 of 435). PoCUS was deemed essential to general EM practice for basic cardiac, aortic, trauma, and procedural imaging. PoCUS was deemed essential to advanced EM practice in undifferentiated symptomatology, advanced chest pathologies, and advanced procedural applications. Expert-level PoCUS competencies were identified for administrative, pediatric, and advanced gynecologic applications. Eighty-seven percent of respondents indicated that there was a need for EM-PoCUS fellowships, with an ideal length of 6 months.

This is the first needs assessment of major stakeholders in Canada to identify competencies for expert training in EM-PoCUS. The competencies should form the basis for EM-PoCUS fellowship programs in Canada.

Traditional variables used to explain survival following out-of-hospital cardiac arrest (OHCA) account for only 72% of survival, suggesting that other unknown factors may influence outcomes. Research on other diseases suggests that neighbourhood factors may partly determine health outcomes. Yet, this approach has rarely been used for OHCA. This work outlines a methodology to investigate multiple neighbourhood factors as determinants of OHCA outcomes.

A retrospective, observational cohort study design will be used. All adult non-emergency medical service witnessed OHCAs of cardiac etiology within the city of Toronto between 2006 and 2010 will be included. Event details will be extracted from the Toronto site of the Resuscitation Outcomes Consortium Epistry—Cardiac Arrest, an existing population-based dataset of consecutive OHCA patients. Geographic information systems technology will be used to assign patients to census tracts. Neighbourhood variables to be explored include the Ontario Marginalization Index (deprivation, dependency, ethnicity, and instability), crime rate, and density of family physicians. Hierarchical logistic regression analysis will be used to explore the association between neighbourhood characteristics and 1) survival-to-hospital discharge, 2) return-of-spontaneous circulation at hospital arrival, and 3) provision of bystander cardiopulmonary resuscitation (CPR). Receiver operating characteristics curves will evaluate each model’s ability to discriminate between those with and without each outcome.

This study will determine the role of neighbourhood characteristics in OHCA and their association with clinical outcomes. The results can be used as the basis to focus on specific neighbourhoods for facilitating educational interventions, CPR awareness programs, and higher utilization of automatic defibrillation devices.