Introduction: For rhythm control of acute atrial flutter (AAFL) in the emergency department (ED), choices include initial drug therapy or initial electrical cardioversion (ECV). We compared the strategies of pharmacological cardioversion followed by ECV if necessary (Drug-Shock), and ECV alone (Shock Only). Methods: We conducted a randomized, blinded, placebo-controlled trial (1:1 allocation) comparing two rhythm control strategies at 11 academic EDs. We included stable adult patients with AAFL, where onset of symptoms was <48 hours. Patients underwent central web-based randomization stratified by site. The Drug-Shock group received an infusion of procainamide (15mg/kg over 30 minutes) followed 30 minutes later, if necessary, by ECV at 200 joules x 3 shocks. The Shock Only group received an infusion of saline followed, if necessary, by ECV x 3 shocks. The primary outcome was conversion to sinus rhythm for ≥30 minutes at any time following onset of infusion. Patients were followed for 14 days. The primary outcome was evaluated on an intention-to-treat basis. Statistical significance was assessed using chi-squared tests and multivariable logistic regression. Results: We randomized 76 patients, and none was lost to follow-up. The Drug-Shock (N = 33) and Shock Only (N = 43) groups were similar for all characteristics including mean age (66.3 vs 63.4 yrs), duration of AAFL (30.1 vs 24.5 hrs), previous AAFL (72.7% vs 69.8%), median CHADS2 score (1 vs 1), and mean initial heart rate (128.9 vs 126.0 bpm). The Drug-Shock and Shock only groups were similar for the primary outcome of conversion (100% vs 93%; absolute difference 7.0%, 95% CI -0.6;14.6; P = 0.25). The multivariable analyses confirmed the similarity of the two strategies (P = 0.19). In the Drug-Shock group 21.2% of patients converted with the infusion. There were no statistically significant differences for time to conversion (84.2 vs 97.6 minutes), total ED length of stay (9.4 vs 7.5 hours), disposition home (100% vs 95.3%), and stroke within 14 days (0 vs 0). Premature discontinuation of infusion (usually for transient hypotension) was more common in the Drug-Shock group (9.1% vs 0.0%) but there were no serious adverse events. Conclusion: Both the Drug-Shock and Shock Only strategies were highly effective and safe in allowing AAFL patients to go home in sinus rhythm. IV procainamide alone was effective in only one fifth of patients, much less than for acute AF.

Introduction: CAEP recently developed the acute atrial fibrillation (AF) and flutter (AFL) [AAFF] Best Practices Checklist to promote optimal care and guidance on cardioversion and rapid discharge of patients with AAFF. We sought to assess the impact of implementing the Checklist into large Canadian EDs. Methods: We conducted a pragmatic stepped-wedge cluster randomized trial in 11 large Canadian ED sites in five provinces, over 14 months. All hospitals started in the control period (usual care), and then crossed over to the intervention period in random sequence, one hospital per month. We enrolled consecutive, stable patients presenting with AAFF, where symptoms required ED management. Our intervention was informed by qualitative stakeholder interviews to identify perceived barriers and enablers for rapid discharge of AAFF patients. The many interventions included local champions, presentation of the Checklist to physicians in group sessions, an online training module, a smartphone app, and targeted audit and feedback. The primary outcome was length of stay in ED in minutes from time of arrival to time of disposition, and this was analyzed at the individual patient-level using linear mixed effects regression accounting for the stepped-wedge design. We estimated a sample size of 800 patients. Results: We enrolled 844 patients with none lost to follow-up. Those in the control (N = 316) and intervention periods (N = 528) were similar for all characteristics including mean age (61.2 vs 64.2 yrs), duration of AAFF (8.1 vs 7.7 hrs), AF (88.6% vs 82.9%), AFL (11.4% vs 17.1%), and mean initial heart rate (119.6 vs 119.9 bpm). Median lengths of stay for the control and intervention periods respectively were 413.0 vs. 354.0 minutes (P < 0.001). Comparing control to intervention, there was an increase in: use of antiarrhythmic drugs (37.4% vs 47.4%; P < 0.01), electrical cardioversion (45.1% vs 56.8%; P < 0.01), and discharge in sinus rhythm (75.3% vs. 86.7%; P < 0.001). There was a decrease in ED consultations to cardiology and medicine (49.7% vs 41.1%; P < 0.01), but a small but insignificant increase in anticoagulant prescriptions (39.6% vs 46.5%; P = 0.21). Conclusion: This multicenter implementation of the CAEP Best Practices Checklist led to a significant decrease in ED length of stay along with more ED cardioversions, fewer ED consultations, and more discharges in sinus rhythm. Widespread and rigorous adoption of the CAEP Checklist should lead to improved care of AAFF patients in all Canadian EDs.

Introduction: An important challenge physicians face when treating acute heart failure (AHF) patients in the emergency department (ED) is deciding whether to admit or discharge, with or without early follow-up. The overall goal of our project was to improve care for AHF patients seen in the ED while avoiding unnecessary hospital admissions. The specific goal was to introduce hospital rapid referral clinics to ensure AHF patients were seen within 7 days of ED discharge. Methods: This prospective before-after study was conducted at two campuses of a large tertiary care hospital, including the EDs and specialty outpatient clinics. We enrolled AHF patients ≥50 years who presented to the ED with shortness of breath (<7 days). The 12-month before (control) period was separated from the 12-month after (intervention) period by a 3-month implementation period. Implementation included creation of rapid access AHF clinics staffed by cardiology and internal medicine, and development of referral procedures. There was extensive in-servicing of all ED staff. The primary outcome measure was hospital admission at the index visit or within 30 days. Secondary outcomes included mortality and actual access to rapid follow-up. We used segmented autoregression analysis of the monthly proportions to determine whether there was a change in admissions coinciding with the introduction of the intervention and estimated a sample size of 700 patients. Results: The patients in the before period (N = 355) and the after period (N = 374) were similar for age (77.8 vs. 78.1 years), arrival by ambulance (48.7% vs 51.1%), comorbidities, current medications, and need for non-invasive ventilation (10.4% vs. 6.7%). Comparing the before to the after periods, we observed a decrease in hospital admissions on index visit (from 57.7% to 42.0%; P <0.01), as well as all admissions within 30 days (from 65.1% to 53.5% (P < 0.01). The autoregression analysis, however, demonstrated a pre-existing trend to fewer admissions and could not attribute this to the intervention (P = 0.91). Attendance at a specialty clinic, amongst those discharged increased from 17.8% to 42.1% (P < 0.01) and the median days to clinic decreased from 13 to 6 days (P < 0.01). 30-day mortality did not change (4.5% vs. 4.0%; P = 0.76). Conclusion: Implementation of rapid-access dedicated AHF clinics led to considerably increased access to specialist care, much reduced follow-up times, and possible reduction in hospital admissions. Widespread use of this approach can improve AHF care in Canada.

Introduction: In-hospital cardiac arrest (IHCA) most commonly occurs in non-monitored areas, where we observed a 10min delay before defibrillation (Phase I). Nurses (RNs) and respiratory therapists (RTs) cannot legally use Automated External Defibrillators (AEDs) during IHCA without a medical directive. We sought to evaluate IHCA outcomes following usual implementation (Phase II) vs. a Theory-Based educational program (Phase III) allowing RNs and RTs to use AEDs during IHCA. Methods: We completed a pragmatic before-after study of consecutive IHCA. We used ICD-10 codes to identify potentially eligible cases and included IHCA cases for which resuscitation was attempted. We obtained consensus on all data definitions before initiation of standardized-piloted data extraction by trained investigators. Phase I (Jan.2012-Aug.2013) consisted of baseline data. We implemented the AED medical directive in Phase II (Sept.2013-Aug.2016) using usual implementation strategies. In Phase III (Sept.2016-Dec.2017) we added an educational video informed by key constructs from a Theory of Planned Behavior survey. We report univariate comparisons of Utstein IHCA outcomes using 95% confidence intervals (CI). Results: There were 753 IHCA for which resuscitation was attempted with the following similar characteristics (Phase I n = 195; II n = 372; III n = 186): median age 68, 60.0% male, 79.3% witnessed, 29.7% non-monitored medical ward, 23.9% cardiac cause, 47.9% initial rhythm of pulseless electrical activity and 27.2% ventricular fibrillation/tachycardia (VF/VT). Comparing Phases I, II and III: an AED was used 0 times (0.0%), 21 times (5.6%), 15 times (8.1%); time to 1st rhythm analysis was 6min, 3min, 1min; and time to 1st shock was 10min, 10min and 7min. Comparing Phases I and III: time to 1st shock decreased by 3min (95%CI -7; 1), sustained ROSC increased from 29.7% to 33.3% (AD3.6%; 95%CI -10.8; 17.8), and survival to discharge increased from 24.6% to 25.8% (AD1.2%; 95%CI -7.5; 9.9). In the VF/VT subgroup, time to first shock decreased from 9 to 3 min (AD-6min; 95%CI -12; 0) and survival increased from 23.1% to 38.7% (AD15.6%; 95%CI -4.3; 35.4). Conclusion: The implementation of a medical directive allowing for AED use by RNs and RRTs successfully improved key outcomes for IHCA victims, particularly following the Theory-Based education video. The expansion of this project to other hospitals and health care professionals could significantly impact survival for VF/VT patients.

Introduction: For rhythm control of acute atrial fibrillation (AAF) in the emergency department (ED), choices include initial drug therapy or initial electrical cardioversion (ECV). We compared the strategies of pharmacological cardioversion followed by ECV if necessary (Drug-Shock), and ECV alone (Shock Only). Methods: We conducted a randomized, blinded, placebo-controlled trial (1:1 allocation) comparing two rhythm control strategies at 11 academic EDs. We included stable adult patients with AAF, where onset of symptoms was <48 hours. Patients underwent central web-based randomization stratified by site. The Drug-Shock group received an infusion of procainamide (15mg/kg over 30 minutes) followed 30 minutes later, if necessary, by ECV at 200 joules x 3 shocks. The Shock Only group received an infusion of saline followed, if necessary, by ECV x 3 shocks. The primary outcome was conversion to sinus rhythm for ≥30 minutes at any time following onset of infusion. Patients were followed for 14 days. The primary outcome was evaluated on an apriori-specified modified intention-to-treat (MITT) basis excluding patients who never received the study infusion (e.g. spontaneous conversion). Data were analyzed using chi-squared tests and logistic regression. Our target sample size was 374 evaluable patients. Results: Of 395 randomized patients, 18 were excluded from the MITT analysis; none were lost to follow-up. The Drug-Shock (N = 198) and Shock Only (N = 180) groups (total = 378) were similar for all characteristics including mean age (60.0 vs 59.5 yrs), duration of AAF (10.1 vs 10.8 hrs), previous AF (67.2% vs 68.3%), median CHADS2 score (0 vs 0), and mean initial heart rate (119.9 vs 118.0 bpm). More patients converted to normal sinus rhythm in the Drug-Shock group (97.0% vs 92.2%; absolute difference 4.8%, 95% CI 0.2-9.9; P = 0.04). The multivariable analyses confirmed the Drug-Shock strategy superiority (P = 0.04). There were no statistically significant differences for time to conversion (91.4 vs 85.4 minutes), total ED length of stay (7.1 vs 7.7 hours), disposition home (97.0% vs 96.1%), and stroke within 14 days (0 vs 0). Premature discontinuation of infusion was more common in the Drug-Shock group (8.1% vs 0.6%) but there were no serious adverse events. Conclusion: Both the Drug-Shock and Shock Only strategies were highly effective and safe in allowing AAF patients to go home in sinus rhythm. A strategy of initial cardioversion with procainamide was superior to a strategy of immediate ECV.

Introduction: Individualizing risk for stroke following a transient ischemic attack (TIA) is a topic of intense research, as existing scores are context-dependent or have not been well validated. The Canadian TIA Score stratifies risk of subsequent stroke into low, moderate and high risk. Our objective was to prospectively validate the Canadian TIA Score in a new cohort of emergency department (ED) patients. Methods: We conducted a prospective cohort study in 14 Canadian EDs over 4 years. We enrolled consecutive adult patients with an ED visit for TIA or nondisabling stroke. Treating physicians recorded standardized clinical variables onto data collection forms. Given the ability of prompt emergency carotid endarterectomy (CEA) to prevent stroke (NNT = 3) in high risk patients, our primary outcome was the composite of subsequent stroke or CEA ≤7 days. We conducted telephone follow-up using the validated Questionnaire for Verifying Stroke Free Status at 7 and 90 days. Outcomes were adjudicated by panels of 3 local stroke experts, blinded to the index ED data collection form. Based on prior work, we estimated a sample size of 5,004 patients including 93 subsequent strokes, would yield 95% confidence bands of +/− 10% for sensitivity and likelihood ratio (LR). Our analyses assessed interval LRs (iLR) with 95% CIs. Results: We prospectively enrolled 7,569 patients with mean 68.4 +/−14.7 years and 52.4% female, of whom 107 (1.4%) had a subsequent stroke and 74 (1.0%) CEA ≤7 days (total outcomes = 181). We enrolled 81.2% of eligible patients; missed patients were similar to enrolled. The Canadian TIA Score stratified the stroke/CEA ≤7days risk as: Low (probability <0.2%, iLR 0.20 [95%CI 0.091-0.44]; Moderate (probability 1.3%, iLR 0.79 [0.68-0.92]; High (probability 2.6%, iLR 2.2 [1.9-2.6]. Sensitivity analysis for just stroke ≤7 days yielded similar results: Low iLR 0.17 [95%CI 0.056-0.52], Medium iLR 0.89 [0.75-1.1], High iLR 2.0 [1.6-2.4]. Conclusion: The Canadian TIA Score accurately identifies TIA patients risk for stroke/CEA ≤7 days. Patients classified as low risk can be safely discharged following a careful ED assessment with elective follow-up. Patients at moderate risk can undergo additional testing in the ED, have antithrombotic therapy optimized, and be offered early stroke specialist follow-up. Patients at high risk should in most cases be fully investigated and managed ideally in consultation with a stroke specialist during their index ED visit.

Introduction: There is an opioid epidemic which has seen an increased mortality rate of 200% related to opioid use over the past decade. Prescription practices amongst ED physicians may be contributing to this problem. Our objective was to analyze ED physician prescription practices for patients discharged from the ED with acute fractures. Methods: We conducted a health records review of ED patients seen at two campuses of a tertiary care hospital with total annual census of 160,000 visits. We evaluated a consecutive sample of patients with acute fractures (January 1 2016–April 15 2016) seen and discharged by ED physicians. Patients admitted to hospital or discharged by consultant services were excluded. The primary outcome measure was the proportion of patients discharged with an opioid prescription. We collected data using a screening list, review of electronic records, and interobserver agreement for measures. We calculated simple descriptive statistics and estimated 4 months would be required to enroll 250 patients receiving opioid prescriptions. Results: We enrolled 816 patients, with 442 females (54.2%), median CTAS score of 3, and median pain score at triage of 6/10. The most common fractures were wrist/hand (35.2%) and foot excluding ankle (14.8%). An ED pain directive was used at triage for 21.2% and 281 patients (34.4%) received an opioid during ED stay, with tramadol (21.2%) being the most common. Overall, 250 patients (30.6%) were discharged with the following opioid prescriptions and median total dosages: hydromorphone (N = 114, median dosage 23mg, range 1–120mg), tramadol (N = 86, 1000mg, 200–2000mg), oxycodone (N = 33, 100mg, 10–170mg), codeine (N = 20, 600mg, 360–1200mg), and morphine (N = 9, 100mg, 25–200mg). Of patients prescribed hydromorphone, 61 (53.5%) were prescribed > 20mg. Overall, 35 patients (4.3%) had a pain related ED visit <1 month after discharge, of which 14 (40%) received an opioid prescription on initial discharge, and 12 (34.2%) received an opioid prescription upon subsequent discharge. Conclusion: Amongst patients presenting to the ED with acute fractures, the majority were not discharged home with an opioid prescription from ED physicians. Hydromorphone was the most common opioid prescribed, with large variations in total dosage. Despite only a minority of patients receiving opioid prescriptions, there were very few return to ED visits. To limit potential abuse, we recommend standardization of opioid prescribing in the ED, with attention to limiting the total dosage given.

Introduction: Guidelines recommend serial conventional cardiac troponin (cTn) measurements 6-9 hours apart for non-ST-elevation myocardial infarction (NSTEMI) diagnosis. We sought to develop a pathway based on absolute/relative changes between two serial conventional cardiac troponin I (cTnI) values 3-hours apart for 15-day MACE identification. Methods: This was a prospective cohort study conducted in the two large ED's at the Ottawa Hospital. Adults with NSTEMI symptoms were enrolled over 32 months. Patients with STEMI, hospitalized for unstable angina, or with only one cTnI were excluded. We collected baseline characteristics, Siemens Vista cTnI at 0 and 3-hours after ED presentation, disposition, and ED length of stay (LOS). Adjudicated primary outcome was 15-day MACE (AMI, revascularization, or death due to cardiac ischemia/unknown cause). We analysed cTnI values by 99th percentile cut-off multiples (45, 100 and 250ng/L). Results: 1,683 patients (mean age 64.7 years; 55.3% female; median ED LOS 7 hours; 88 patients with 15-day MACE) were included. 1,346 (80.0%) patients with both cTnI ≤45ng/L; and 58 (3.4%) of the 213 patients with one value≥100ng/L but both <250ng/L or ≤20% change did not suffer MACE. Among 124 patients (7.4%) with one value >45ng/L but both <100ng/L based on 3 or 6-hour cTnI, one patient with Δ<10ng/L and 6 of 19 patients with Δ≥20ng/L were diagnosed with NSTEMI (patients with Δ10-19ng/L between first and second cTnI had third one at 6-hours). Based on the results, we developed the Ottawa Troponin Pathway (OTP) with a 98.9% sensitivity (95%CI 96.7-100%) and 94.6% specificity (95%CI 93.4-95.7%). Conclusion: The OTP, using two conventional cTnI measurements performed 3-hours apart, should lead to better identification of NSTEMI particularly those with values >99th percentile cut-off, standardize management and reduce the ED LOS.

Introduction: Patients with diabetes who are in emerging adulthood, defined as the life stage between 18-29 years, have unique challenges in managing their illness and are at risk of acute complications and loss to follow-up. The studys objective was to describe emergency department (ED) utilization for hyperglycemia in emerging adults with diabetes and to characterize 30-day outcomes including return visits and admission for hyperglycemia. Methods: This was a health records review of emerging adults presenting over a one-year period to four tertiary care EDs with a diagnosis of hyperglycemia, diabetic ketoacidosis or hyperosmolar hyperglycemic state. Research personnel collected data on patient characteristics, treatment, disposition, and determined if patients returned to the ED for hyperglycemia within 30 days. Descriptive statistics were used to summarize the data where appropriate. Results: There were 185 ED encounters for hyperglycemia, representing 116 unique emerging adult patients. Mean (SD) age was 23 (3.5) years and 50.9% were female. 80 (69.0%) had known type 1 diabetes, 11 (9.5%) had type 2, and 25 (21.5%) were newly diagnosed in the ED. Of 185 visits, 98 (53.0%) resulted in hospital admission. 56 (30.3%) returned to the ED for hyperglycemia within 30 days of their initial encounter, and 21 (11.4%) resulted in admission on this subsequent visit. Conclusion: We characterized ED utilization and 30-day outcomes of emerging adults with diabetes for hyperglycemia. Future research should focus on earlier identification of those at higher risk for recurrent ED visits or admission and the efficacy of interventions to prevent these adverse outcomes.

Introduction: The Ottawa SAH Rule was developed to identify patients at high-risk for subarachnoid hemorrhage (SAH) who require investigations and the 6-Hour CT Rule found that computed tomography (CT) was 100% sensitive for SAH 6 hours of headache onset. Together, they form the Ottawa SAH Strategy. Our objectives were to assess: 1) Safety of the Ottawa SAH Strategy and its 2) Impact on: a) CTs, b) LPs, c) ED length of stay, and d) CT angiography (CTA). Methods: We conducted a multicentre prospective before/after study at 6 tertiary-care EDs January 2010 to December 2016 (implementation July 2013). Consecutive alert, neurologically intact adults with a headache peaking within one hour were included. SAH was defined by subarachnoid blood on head CT (radiologists final report); xanthochromia in the cerebrospinal fluid (CSF); >1x106/L red blood cells in the final tube of CSF with an aneurysm on CTA. Results: We enrolled 3,669 patients, 1,743 before and 1,926 after implementation, including 185 with SAH. The investigation rate before implementation was 89.0% (range 82.9 to 95.6%) versus 88.4% (range 85.2 to 92.3%) after implementation. The proportion who had CT remained stable (88.0% versus 87.4%; p=0.60), while the proportion who had LP decreased from 38.9% to 25.9% (p<0.001), and the proportion investigated with CTA increased from 18.8% to 21.6% (p=0.036). The additional testing rate (i.e. LP or CTA) diminishedfrom 50.1% to 40.8% (p<0.001). The proportion admitted declined from 9.8% to 7.3% (p=0.008), while the mean length of ED stay was stable (6.2 +/− 4.0 to 6.4 +/− 4.1 hours; p=0.45). For the 1,201 patients with CT 6 hours, there was an absolute decrease in additional testing (i.e. LP or CTA) of 15.0% (46.6% versus 31.6%; p<0.001). The sensitivity of the Ottawa SAH Rule was 100% (95%CI: 98-100%), and the 6-Hour CT Rule was 95.3% (95%CI: 88.9-98.3) for SAH. Five patients with early CT had SAH with CT reported as normal: 2 unruptured aneuryms on CTA and presumed traumatic LP (determined by treating neurosurgeon); 1 missed by the radiologist on the initial interpretation; 1 dural vein fistula (i.e. non-aneuyrsmal); and 1 profoundly anemic (Hgb 63g/L). Conclusion: The Ottawa SAH Strategy is highly sensitive and can be used routinely when SAH is being considered in alert and neurologically intact headache patients. Its implementation was associated with a decrease in LPs and admissions to hospital.

Introduction: Current guideline recommendations for optimal management of non-purulent skin and soft tissue infections (SSTIs) are based on expert consensus. There is currently a lack of evidence to guide emergency physicians on when to select oral versus intravenous antibiotic therapy. The primary objective was to identify risk factors associated with oral antibiotic treatment failure. A secondary objective was to describe the epidemiology of adult emergency department (ED) patients with non-purulent SSTIs. Methods: We performed a health records review of adults (age 18 years) with non-purulent SSTIs treated at two tertiary care EDs. Patients were excluded if they had a purulent infection or infected ulcers without surrounding cellulitis. Treatment failure was defined any of the following after a minimum of 48 hours of oral therapy: (i) hospitalization for SSTI; (ii) change in class of oral antibiotic owing to infection progression; or (iii) change to intravenous therapy owing to infection progression. Multivariable logistic regression was used to identify predictors independently associated with the primary outcome of oral antibiotic treatment failure after a minimum of 48 hours of oral therapy. Results: We enrolled 500 patients (mean age 64 years, 279 male (55.8%) and 126 (25.2%) with diabetes) and the hospital admission rate was 29.6%. The majority of patients (70.8%) received at least one intravenous antibiotic dose in the ED. Of 288 patients who had received a minimum of 48 hours of oral antibiotics, there were 85 oral antibiotic treatment failures (29.5%). Tachypnea at triage (odds ratio [OR]=6.31, 95% CI=1.80 to 22.08), chronic ulcers (OR=4.90, 95% CI=1.68 to 14.27), history of MRSA colonization or infection (OR=4.83, 95% CI=1.51 to 15.44), and cellulitis in the past 12 months (OR=2.23, 95% CI=1.01 to 4.96) were independently associated with oral antibiotic treatment failure. Conclusion: This is the first study to evaluate potential predictors of oral antibiotic treatment failure for non-purulent SSTIs in the ED. We observed a high rate of treatment failure and hospitalization. Tachypnea at triage, chronic ulcers, history of MRSA colonization or infection and cellulitis within the past year were independently associated with oral antibiotic treatment failure. Emergency physicians should consider these risk factors when deciding on oral versus intravenous antimicrobial therapy for non-purulent SSTIs being managed as outpatients.

Introduction: Two published studies reported natriuretic peptides can aid in risk-stratification of Emergency Department (ED) syncope. We sought to assess the role of N-Terminal pro Brain Natriuretic Peptide (NT pro-BNP) to identify syncope patients at risk for serious adverse events (SAE) within 30 days of the ED visit, and its value above that of the Canadian Syncope Risk Score (CSRS). Methods: We conducted a multicenter prospective cohort study at 6 large Canadian EDs from Nov 2011 to Feb 2015. We enrolled adults who presented within 24-hours of syncope and excluded those with persistent altered mentation, obvious seizure, and intoxication. We collected patient characteristics, nine CSRS predictors (includes troponin), ED management and NT pro-BNP levels. Adjudicated serious adverse events (SAE) included death, cardiac SAE (arrhythmias, myocardial infarction, serious structural heart disease) and non-cardiac SAE (pulmonary embolism, severe hemorrhage and procedural interventions within 30-days). We used two tailed t-test and logistic regression analysis. Results: Of the 1359 patients (mean age 57.2 years, 54.7% females, 13.3% hospitalized) enrolled, 148 patients (10.9%; 0.7% deaths, 7.9% cardiac SAE including 6.1% arrhythmia) suffered SAE within 30-days. The mean NT pro-BNP values, when compared to the patients with no SAE (499.8ng/L) was significantly higher among the 56 patients who suffered SAE after ED disposition (3147ng/L, p=0.001), and among the 35 patients with cardiac SAE after ED disposition (2016.2ng/L, p=0.02). While there was a trend to higher levels among patients who suffered arrhythmia after the ED visit, it was not statistically significant (1776.4ng/L, p=0.07). In a model with CSRS predictors, the adjusted odds ratio for NT pro-BNP was 8.0 (95%CI 1.8, 35.9) and troponin was 3.8 (95%CI 1.7, 8.8). The addition of NT pro-BNP did not significantly improve the classification performance (p=0.76) with areas under the curves for CSRS was 0.91 (95%CI 0.88, 0.95) and CSRS with NT pro-BNP was 0.92 (95%CI 0.88, 0.95). Conclusion: In this multicenter study, mean NT pro-BNP levels were significantly higher among ED syncope patients who suffered SAE including cardiac SAE after ED disposition. Though NT pro-BNP was a significant independent predictor of SAE after ED disposition, it did not improve accuracy in ED syncope risk-stratification when compared to CSRS. Hence, we do not recommend NT pro-BNP measurement for ED syncope management.

Introduction: There is a significant gap between the number of organ donors and people awaiting an organ transplant; therefore it is essential that all potential donors are identified. Given the nature of Emergency Medicine it is a potential source of organ donors. The purpose of this study is to determine what percent of successful donors come from the Emergency Department (ED) and whether there are any missed potential donors. Methods: Electronic searches of EMBASE, MEDLINE, and CINAHL were performed July 7, 2017 using PRISMA guidelines. Primary literature in human adults were included if they described identification of patients in the ED who went on to become successful solid organ donors, or described missed potential donors in the ED. Data on the total population of actual or missed donors was required to allow calculation of a percentage. Studies describing non-solid organ donation, consent, ethics, survey of attitudes, teaching curricula, procurement techniques, donation outside the ED, and recipient factors were excluded. 2 authors independently screened articles for inclusion and discrepancies were resolved through consensus. Quality was assessed using STROBE for observational studies. Heterogeneity of patient populations precluded pooling of the data to conduct a meta-analysis. Results: 1058 articles were identified, 17 duplicates were removed, 800 articles were excluded based on title and abstract, and 217 full text articles were excluded, yielding 24 articles for the systematic review. For neurologic determination of death (NDD), ED patients comprised 4 44% of successful donors. ED death reviews revealed 0 84% of patients dying in the ED are missed as potential donors and hospital-wide death reviews revealed 13 80.9% of missed donors die in the ED. For donation after cardiac death (DCD), 4 20% of successful donors came from the ED and studies investigating potential donors suggest 2 36% of patients dying the in the ED could be potential DCD donors. The most common population of successful DCD organ donors was in traumatic cardiopulmonary arrest (TCPA), with 3.6 8.9% of TCPA patients presenting to the ED becoming successful donors. Conclusion: Patients dying in the Emergency Department are a significant source of both successful organ donors and missed potential donors. Emergency physicians should be familiar with their local organ donation protocol to ensure potential organ donors are not missed.

Introduction: Out-of-hospital cardiac arrest (OHCA) is associated with high mortality, and CPR quality is one of the few modifiable factors associated with improved outcomes. Particularly, bystander CPR has been shown to improve survival and neurological outcomes in OHCA. However, the quality of CPR performed by bystanders in OHCA is unknown. We evaluated bystander CPR quality during OHCA, utilizing data stored within Automated External Defibrillators (AEDs), and matched with cases enrolled in the Resuscitation Outcomes Consortium (ROC) database. Methods: This cohort study included adult OHCA cases from the Ottawa ROC site between 2011-2016, which were of presumed cardiac etiology, not witnessed by EMS, and where an AED was utilized by a bystander with > 1 minute of CPR process data available. AED data from Ottawa Paramedic Services was matched to each case identified by the ROC database. AED data was analyzed using manufacturer software to determine overall measures of bystander CPR quality, changes in bystander CPR quality over time, and bystander adherence to existing 2010 Resuscitation Guidelines. Results: 100 cases met all inclusion criteria. 75.0% of patients were male, with a mean age of 62.3 years. 58.0% of arrests occurred in the home setting, and 24.0% were witnessed arrests. Initial rhythm was ventricular fibrillation/ventricular tachycardia in 36.0% of cases. Overall survival rate was 42.0%, with a modified Rankin Score of 3.7 (95% CI: 2.9-4.5). Bystanders demonstrated high-quality CPR over the course of resuscitation, with a chest compression fraction (CCF) of 75.9% (73.6-78.1), a compression depth of 5.26 cm (5.03-5.49), and a compression rate of 111.2/min (107.7-114.7). Mean peri-shock pause was 26.8 seconds (24.6-29.1). Adherence rates to 2010 Resuscitation Guidelines for compression rate and depth were 66.0% (60.9-71.1) and 54.9% (48.6-61.3), respectively. CPR quality was lowest in the first minute of resuscitation, during which rhythm analysis took place (mean 40.5 sec). In cases involving a shockable rhythm, overall latency from initiation of AED to shock delivery was 59.2 sec (45.5-72.8). Conclusion: We found that bystanders perform high-quality CPR, with strong adherence rates to existing Resuscitation Guidelines. Our findings provide evidence of the quality of bystander CPR performed during OHCA.

Introduction: Decision fatigue is a well-characterized phenomenon that has rarely been studied in the medical field. Emergency department (ED) physicians make many clinical decisions every shift. In this study, we examined ED physician decisions in computed tomography (CT) ordering, consultations, and discharges over time in an eight-hour shift. Methods: We performed a cohort study of adult patients presenting to two EDs of an academic, tertiary care hospital over a two-year period using the hospital administrative database. Patients triaged to the Urgent Care (minor acuity) area of the ED were excluded. Patients were analyzed based on the hour of the shift that they were initially assessed by an ED physician. For each hour, we evaluated the proportion of patients who had CTs, consultations, discharges, consultations not resulting in admission, returns within 72 hours of discharge, and median ED length of stay (LOS). Patients under the care of more than one ED physician (i.e. handovers) were analyzed as the time seen by the initial physician. Statistical significance of outcomes over time was assessed using random effects logistic regression. Results: 87,752 patients were included in the study period. 42,146 patients (48.0%) received consultations, of which, 29,347 (69.6%) were admitted. 45,470 patients (51.8%) were discharged without consultation, of which, 4102 (9.0%) returned within 72 hours. The median ED LOS for all non-consulted discharged patients was 4.9 hours. There was a statistically significant decline in the hourly rates of CT head and CT abdomen ordering as the shift progressed. CT head ordering declined significantly from 15.8% in the first hour to 12.2% in the last hour (p<0.0001) while CT abdomen declined significantly from 9.6% to 7.6% (p<0.0001). There were no significant differences in the hourly rates of consultations, consultations not resulting in admission, discharges, discharges returning within 72 hours, or ED LOS. Conclusion: ED physician decisions about patient disposition did not change in relation to hours into the shift. Interestingly, the rates of CT head and CT abdomen declined as the shift progressed. The lower CT ordering rates do not seem to be associated with any differences in patient disposition or ED LOS. In this large patient sample, we did not find evidence of decision fatigue among ED physicians.

Introduction: Creatine kinase (CK) measurement, despite not being recommended for the diagnosis of a Non-ST Elevation Myocardial Infarction (NSTEMI) is still routinely performed in the emergency department (ED) for the workup of NSTEMI. The diagnostic utility of CK among ED patients with suspected NSTEMI is still not well understood. The objectives of this study were to assess: the additional value of CK in NSTEMI diagnosis and the correlation between the highest CK/TNI values and ejection fraction (EF) on follow-up echocardiography among patients with suspected NSTEMI. Methods: This was a prospective cohort study conducted at the Civic and General Campuses of The Ottawa Hospital from March 2014 to March 2016. We enrolled adults (18 years) for whom troponin (TNI) and CK were ordered for chest pain or non-chest pain symptoms within the past 24 hours concerning for NSTEMI and excluded those with suspected ST-Elevation Myocardial Infarction (STEMI). Primary outcome was a 30-day NSTEMI adjudicated by two blinded physicians. Demographics, medical history, and ED CK/TNI values were collected. We used descriptive statistics and report test diagnostic characteristics. Results: Of the 1,663 patients enrolled, 84 patients (5.1%) suffered NSTEMI. The sensitivity and specificity of CK was 30.9% (95%CI 21.1, 40.8) and 91.4% (95%CI 90.0, 92.8) respectively. The sensitivity and specificity of troponin was 96.4% (95%CI 92.4, 100) and 88.1% (95%CI 86.5, 89.7) respectively. Among 3 (0.2%) patients with missed NSTEMI diagnosis with TNI, CK measurements did not add value. The mean CK values were not significantly different between those with normal and abnormal EF on follow-up (132.4 U/L and 146.3 U/L respectively; p=0.44), whereas the mean TNI values were significantly different (0.5 µg/L and 1.3 µg/L respectively; p=0.046). Conclusion: CK measurements neither provide any additional value in the work-up of NSTEMI in the ED nor correlate with EF on follow-up. Discontinuing routine CK measurements would reduce overall costs and improve resource utilization in the ED, and streamline the management of patients in the ED with chest pain.

Introduction: Emergency department (ED) patients with non-purulent skin and soft tissue infections (SSTIs) requiring intravenous antibiotics may be managed via outpatient parenteral antibiotic therapy (OPAT). To date, there are no prospective studies describing the performance of an ED-to-OPAT clinic program. Furthermore, there are no studies that have examined physician rationale for intravenous therapy, despite this being a critical first step in the decision to refer to an OPAT program. Methods: We conducted a prospective observational cohort study of adults (age 18 years) with non-purulent SSTIs receiving parenteral therapy at two tertiary care EDs. Patients were excluded if they had purulent infections or could not provide consent. The emergency physician completed a form documenting rationale for intravenous therapy, infection size, and choice of antimicrobial agent, dose and duration. OPAT treatment failure was defined as hospitalization after a minimum of 48 hours of OPAT for: (i) worsening infection; (ii) peripheral intravenous line complications; or (iii) adverse antibiotic events. Patient satisfaction was assessed at a 14-day telephone follow up. Results: We enrolled a consecutive sample of 153 patients (mean age 60 years, 82 male (53.6%) and 38 (24.8%) with diabetes). A total of 137 patients (89.5%) attended their clinic appointment. Of the 101 patients prescribed cefazolin, 50.5% received 1000 mg and 48.5% received 2000 mg per day. There were low rates of OPAT treatment failure (3.9%). None of the adverse peripheral intravenous line events (9.8%) or adverse antibiotic events (7.2%) required hospitalization. Patients reported a high degree of satisfaction with timeliness of clinic referral (median score 9 out of 10) and overall care received (median score of 10 out of 10). The top 5 reasons given by physicians for selecting intravenous therapy were: clinical impression of severity (52.9%); failed oral antibiotic therapy (41.8%); diabetes (17.6%); severe pain (7.8%); and peripheral vascular disease (7.8%). Conclusion: This is the first study to identify physician rationale for the use of intravenous antibiotics for SSTIs. There was significant variability in antibiotic prescribing practices by ED physicians. This prospective study demonstrates that an ED-to-OPAT clinic program for non-purulent SSTIs is safe, has a low rate of treatment failures and results in high patient satisfaction.

Introduction: Patients with acute atrial fibrillation or flutter (AAFF) are the most common acute arrhythmia cases requiring care in the ED. Our goal was to adapt the existing Canadian Cardiovascular Society (CCS) AF Management Guidelines into an emergency physician-friendly best practices checklist. Methods: We chose to adapt, for use by emergency physicians, existing high-quality clinical practice guidelines (CPG) previously developed by the CCS using the GRADE system. We used the Canadian CAN-IMPLEMENT© process adapted from the ADAPTE Collaboration. We created an Advisory Committee consisting of 14 academic and community emergency physicians, three cardiologists, one PhD methodologist, and two patients. The Advisory Committee communicated by a two-day face-to-face meeting, teleconferences, and email. The checklist was prepared and revised through a process of feedback and discussions through ten iterations until consensus was achieved. We then circulated the draft checklist for comment to approximately 300 emergency medicine and cardiology colleagues whose written feedback was further incorporated into the final approved version. Results: The final CAEP ED AAFF Guidelines are comprised of two algorithms and four sets of checklists, organized by 1) Assessment and Risk Stratification, 2) Rhythm and Rate Control, 3) Long-term Stroke Prevention with the CHADS-65 Algorithm, and 4) Disposition and Follow-up. The guidelines have been endorsed by CAEP and accepted for publication in the Canadian Journal of Emergency Medicine. During the consensus and feedback processes, we addressed a number of issues and concerns. We highlighted the issue that many unstable patients are actually suffering from underlying medical problems rather than a primary arrhythmia. One controversial recommendation is to consider rate control or transesophageal echocardiography guided cardioversion if the duration of symptoms is 24-48 hours and the patient has two or more CHADS-65 criteria. We emphasize the importance of evaluating long-term stroke risk by use of the CHADS-65 algorithm and encourage ED physicians to prescribe anticoagulants where indicated. Conclusion: We have created the CAEP AAFF Best Practices Checklist which we hope will standardize and improve care of AAFF patients in all EDs across Canada. We believe that most of these patients can be managed rapidly and safely with ED rhythm control, early discharge, and appropriate use of anticoagulants.

Introduction: The Canadian Syncope Risk Score (CSRS) was developed to identify patients at risk for serious adverse events (SAE) within 30 days of an Emergency Department (ED) visit for syncope. We sought to validate the score in a new cohort of ED patients. Methods: We conducted a multicenter prospective cohort study at 8 large academic tertiary-care EDs across Canada from March 2014 to Dec 2016. We enrolled adults (age 16 years) who presented within 24 hours of syncope, after excluding those with persistent altered mentation, witnessed seizure, intoxication, and major trauma requiring hospitalization. Treating ED physicians collected the nine CSRS predictors at the index visit. Adjudicated SAE included death, arrhythmias and non-arrhythmic SAE (myocardial infarction, serious structural heart disease, pulmonary embolism, severe hemorrhage and procedural interventions within 30-days). We assessed area under the Receiver Operating Characteristic (ROC) curve, score calibration, and the classification performance for the various risk categories. Results: Of the 2547 patients enrolled, 146 (5.7%) were lost to follow-up and 111 (4.3%) had serious condition during the index ED visit and were excluded. Among the 2290 analyzed, 79 patients (3.4%; 0.4% death, 1.4% arrhythmia) suffered 30-day serious outcomes after ED disposition. The accuracy of the CSRS remained high with area under the ROC curve at 0.87 (95%CI 0.82-0.92), similar to the derivation phase (0.87; 95%CI 0.84-0.89). The score showed excellent calibration at the prespecified risk strata. For the very-low risk category (0.3% SAE of which 0.2% were arrhythmia and no deaths) the sensitivity was 97.5% and negative predictive value was 99.7% (95%CI 98.7-99.9). For the very high-risk category (61.5% SAE of which 26.9% were arrhythmia and 11.5% death) the specificity was 99.4% and positive predictive value was 61.5% (95% CI 43.0-77.2). Conclusion: In this multicenter validation study, the CSRS accurately risk stratified ED patients with syncope for short-term serious outcomes after ED disposition. The score should aid in minimizing investigation and observation of very-low risk patients, and prioritization of inpatient vs outpatient investigations or following of the rest. The CSRS is ready for implementation studies examining ED management decisions, patient safety and health care resource utilization.

Introduction: Despite widespread use of FAST in trauma, there is a lack of data supporting its usefulness. We sought to identify the impact of FAST on clinical management of blunt trauma patients. Methods: This health records review was conducted at a single large academic Level 1 trauma center emergency department. Patients with a suspicion of acute blunt traumatic abdominal injury were identified from our health records database. Data were collected regarding FAST utilization, CT scan utilization and timing, need for definitive management, disposition, and length of stay (LOS). Results: 285 patients were included, 152 (53.3%) received a FAST examination, with 33 (22%) having a direct impact on clinical management. CT was performed in 112 (73.6%) of the FAST group, with mean time to imaging of 147.4 minutes, time to trauma team assessment of 21.5 minutes, and ED-LOS of 8.6 hours. In the non-FAST group, 33 (24.8%) received a CT, with time to imaging of 133 minutes, time to trauma team assessment of 133 minutes, and ED-LOS of 13.8 hours. 75.6% of the FAST group required admission and 9.2% required definitive management; admission was needed for 38.3% of the non-FAST group and 2.2% required definitive management. Conclusion: This is the first study to assess patient outcomes with respect to FAST in the era of early whole body CT in trauma. Although FAST does not directly impact care for the majority of blunt trauma patients, it demonstrates usefulness in some patients by directing CT utilization and expediting disposition from the ED.