David Barbic

Point-of-care Ultrasonography for the Diagnosis of Acute Cardiogenic Pulmonary Edema in Patients Presenting With Acute Dyspnea: A Systematic Review and Meta-analysis

OBJECTIVES Acute dyspnea is a common presenting complaint to the emergency department (ED), and point-of-care (POC) lung ultrasound (US) has shown promise as a diagnostic tool in this setting. The primary objective of this systematic review was to determine the sensitivity and specificity of US using B-lines in diagnosing acute cardiogenic pulmonary edema (ACPE) in patients presenting to the ED with acute dyspnea. METHODS A systematic review protocol adhering to Cochrane Handbook guidelines was created to guide the search and analysis, and we searched the following databases: PubMed, EMBASE, Ovid MEDLINE, Ovid MEDLINE In-Process & Other Non-Indexed Citations, and the Cochrane Database of Systematic Reviews. References of reviewed articles were hand-searched, and electronic searches of conference abstracts from major emergency medicine, cardiology, and critical care conferences were conducted. The authors included prospective cohort and prospective case-control studies that recruited patients presenting to hospital with symptomatic, acute dyspnea, or where there was a clinical suspicion of congestive heart failure, and reported the sensitivity and specificity of B-lines in diagnosing ACPE. Studies of asymptomatic individuals or in patients where there was no suspicion of ACPE were excluded. The outcome of interest was a diagnosis of ACPE using US B-lines. A final diagnosis from clinical follow-up was accepted as the reference standard. Two reviewers independently reviewed all citations to assess for inclusion, abstracted data, and assessed included studies for methodologic quality using the QUADAS-2 tool. Contingency tables were used to calculate sensitivity and specificity. Three subgroup analyses were planned a priori to examine the effects of the type of study, patient population, and lung US protocol employed. RESULTS Seven articles (n = 1,075) were identified that met inclusion criteria (two studies completed in the ED, two in the intensive care unit [ICU], two on inpatient wards, and one in the prehospital setting). The seven studies were rated as average to excellent methodologic quality. The sensitivity of US using B-lines to diagnosis ACPE is 94.1% (95% confidence interval [CI] = 81.3% to 98.3%) and the specificity is 92.4% (95% CI = 84.2% to 96.4%). Preplanned subgroup analyses did not reveal statistically significant changes in the overall summary estimates, nor did exclusion of three potential outlier studies. CONCLUSIONS This study suggests that in patients with a moderate to high pretest probability for ACPE, an US study showing B-lines can be used to strengthen an emergency physicians working diagnosis of ACPE. In patients with a low pretest probability for ACPE, a negative US study can almost exclude the possibility of ACPE. Further studies including large numbers of ED patients presenting with undifferentiated dyspnea are required to gain more valid and reliable estimates of test accuracy in ED patients.

An Analysis of Altmetrics in Emergency Medicine

OBJECTIVES Alternative-level metrics (Altmetrics) are a new method to assess the sharing and spread of scientific knowledge. The primary objective of this study was to describe the traditional metrics and Altmetric scores of the 50 most frequently cited articles published in emergency medicine (EM) journals. Since many articles related to EM are published in other journals, the secondary aim of this study was to describe the Altmetric scores of the most frequently cited articles relevant to EM in other biomedical journals. METHODS A structured search of the Institute for Scientific Information Web of Science version of the Science Citation Index Expanded was conducted. The 200 most frequently cited articles in the top 10 EM journals (2011 Journal Citation Report) were identified. The 200 most frequently cited articles from the rest of the medical literature, matching a predefined list of keywords relevant to the specialty of EM, were identified. Two authors reviewed the lists of citations for relevance to EM and a consensus approach was used to arrive at the final lists of the top 50 cited articles. The Altmetric scores for the top 50 cited articles in EM and other journals were determined. Descriptive statistics and Spearman correlation were performed. RESULTS The highest Altmetric score for EM articles was 25.0; the mean (±SD) was 1.9 (±5.0). The EM journal with the highest mean article Altmetric score was Resuscitation. The main clinical areas shared for articles from EM articles were trauma (mean ± SD = 11.0 ± 15.6, median = 11.0) and cardiac arrest (mean ± SD = 2.7 ± 5.8, median = 0). The highest Altmetric score for other journals was 176.0 (mean ± SD = 23.3 ± 40.8). The other journal with the highest mean article Altmetric score was the New England Journal of Medicine. The main clinical areas shared for articles were critical care (mean ± SD score = 36.5 ± 47.4, median = 36.5), sepsis (mean ± SD = 24.6 ± 48.8, median = 12.0), cardiology (mean ± SD = 19.2 ± 35.6, median = 7.0), and infectious diseases (mean ± SD = 17.0 ± 12.7, median = 17.0). Spearman correlation demonstrated weakly positive correlation between citation counts and Altmetric scores for EM articles and other journals. CONCLUSIONS This study is the first analysis of Altmetric scores for the top cited articles in EM. We demonstrated that there is a mild correlation between citation counts and Altmetric scores for the top papers in EM and other biomedical journals. We also demonstrated that there is a gap between the sharing of the top articles in EM journals and those related to EM in other biomedical journals. Future research to explore this relationship and its temporal trends will benefit the understanding of the reach and dissemination of EM research within the scientific community and society in general.

An exploration of Canadian emergency physicians' and residents' knowledge of computed tomography radiation dosing and risk

OBJECTIVE The objective of this study was to measure the current knowledge of Canadian emergency physicians and emergency medicine residents regarding computed tomography (CT) radiation dosing and its associated risks. METHODS Three focus groups were conducted as the qualitative element of this study. Cognitive debriefing was carried out to ensure the validity and reliability of the focus group findings and to aid with survey development. A 26-item electronic survey was developed and pilot tested for distribution to the membership of the Canadian Association of Emergency Physicians. RESULTS Eighteen emergency medicine physicians and three emergency medicine residents participated in the focus groups. Four major themes emerged: 1) physician knowledge of risks associated with CT, 2) risk management strategies, 3) communication, and 4) knowledge translation. The survey response rate was 49.8% (638 of 1,281). The mean respondent age was 40.9±9.9 years, and 70.7% were male. Of all respondents, 82.5% were actively practicing attending physicians, 56.4% of all respondents practiced in urban academic emergency departments, and the average time practicing was 10.7±9.6 years. Radiography and CT were correctly identified by 92.2% and 95.1% of respondents, respectively, as sources of ionizing radiation, whereas magnetic resonance imaging and ultrasonography were selected by 1.0% and 0.5%, respectively. With respect to the lifetime attributable risk (LAR) of malignancy due to CT, 82.2% of participants correctly identified that abdominal CT increases the risk of cancer by 0.2 to 2%, whereas 51.3% correctly identified that the LAR increases twofold in a 7- year-old boy. When asked to identify populations at risk for potential harm due to ionizing radiation, 92.2% of respondents identified children, 80.3% identified pregnant women, and 71.4% identified women of reproductive age. A minority (37.2%) reported communicating the potential risks of CT to a majority of their patients. Electronic platforms were identified by 74.8% of respondents as their preferred method of knowledge translation on this topic. CONCLUSIONS Canadian emergency medicine physicians and emergency medicine residents demonstrated identifiable gaps in knowledge surrounding CT radiation dose and risk.

In patients presenting to the emergency department with skin and soft tissue infections what is the diagnostic accuracy of point-of-care ultrasonography for the diagnosis of abscess compared to the current standard of care? A systematic review and meta-analysis

Objectives The primary objective of this systematic review was to determine the accuracy of point-of-care ultrasonography (POCUS) in diagnosing abscess in emergency department (ED) patients with skin and soft tissue infections (SSTI). The secondary objective was the accuracy of POCUS in the paediatric population subgroup. Setting Prospective studies set in emergency departments. Participants Emergency department patients (adult and paediatric) presenting with SSTI and suspected abscess. Primary and secondary outcome measures This systematic review was conducted according to Cochrane Handbook guidelines, and the following databases were searched: PubMed, MEDLINE, EMBASE and the Cochrane database of systematic reviews (1946–2015). We included prospective cohort and case–control studies investigating ED patients with SSTI and abscess or cellulitis, a defined POCUS protocol, a clearly defined gold standard for abscess and a contingency table describing sensitivity and specificity. Two reviewers independently ascertained all potentially relevant citations for methodologic quality according to QUADAS-2 criteria. The primary outcome measure was the sensitivity and specificity of POCUS for abscess. A preplanned subgroup (secondary) analysis examined the effects in paediatric populations, and changes in management were explored post hoc. Results Of 3028 articles, 8 were identified meeting inclusion criteria; all were rated as good to excellent according to QUADAS-2 criteria. Combined test characteristics of POCUS on the ED diagnosis of abscess for patients with SSTI were as follows: sensitivity 96.2% (95% CI 91.1% to 98.4%), specificity 82.9% (95% CI 60.4% to 93.9%), positive likelihood ratio 5.63 (95% CI 2.2 to 14.6) and negative likelihood ratio 0.05 (95% CI 0.01 to 0.11). Conclusions A total of 8 studies of good-to-excellent quality were included in this review. The use of POCUS helps differentiate abscess from cellulitis in ED patients with SSTI. Trial registration number CRD42015017115.

Safety of a Brief Emergency Department Observation Protocol for Patients With Presumed Fentanyl Overdose

Study objective: Fentanyl overdoses are increasing and few data guide emergency department (ED) management. We evaluate the safety of an ED protocol for patients with presumed fentanyl overdose. Methods: At an urban ED, we used administrative data and explicit chart review to identify and describe consecutive patients with uncomplicated presumed fentanyl overdose (no concurrent acute medical issues) from September to December 2016. We linked regional ED and provincial vital statistics databases to ascertain admissions, revisits, and mortality. Primary outcome was a composite of admission and death within 24 hours. Other outcomes included treatment with additional ED naloxone, development of a new medical issue while in the ED, and length of stay. A prespecified subgroup analysis assessed low‐risk patients with normal triage vital signs. Results: There were 1,009 uncomplicated presumed fentanyl overdose, mainly by injection. Median age was 34 years, 85% were men, and 82% received out‐of‐hospital naloxone. One patient was hospitalized and one discharged patient died within 24 hours (combined outcome 0.2%; 95% confidence interval [CI] 0.04% to 0.8%). Sixteen patients received additional ED naloxone (1.6%; 95% CI 1.0% to 2.6%), none developed a new medical issue (0%; 95% CI 0% to 0.5%), and median length of stay was 173 minutes (interquartile range 101 to 267). For 752 low‐risk patients, no patients were admitted or developed a new issue, and one died postdischarge; 3 (0.4%; 95% CI 0.01% to 1.3%) received ED naloxone. Conclusion: In our cohort of ED patients with uncomplicated presumed fentanyl overdose—typically after injection—deterioration, admission, mortality, and postdischarge complications appear low; the majority can be discharged after brief observation. Patients with normal triage vital signs are unlikely to require ED naloxone.

Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests

Background: Survival following out-of-hospital cardiac arrest (OHCA) with shockable rhythms can be improved with early defibrillation. Although shockable OHCA accounts for only ≈25% of overall arrests, ≈60% of public OHCAs are shockable, offering the possibility of restoring thousands of individuals to full recovery with early defibrillation by bystanders. We sought to determine the association of bystander automated external defibrillator use with survival and functional outcomes in shockable observed public OHCA. Methods: From 2011 to 2015, the Resuscitation Outcomes Consortium prospectively collected detailed information on all cardiac arrests at 9 regional centers. The exposures were shock administration by a bystander-applied automated external defibrillator in comparison with initial defibrillation by emergency medical services. The primary outcome measure was discharge with normal or near-normal (favorable) functional status defined as a modified Rankin Score ⩽2. Survival to hospital discharge was the secondary outcome measure. Results: Among 49 555 OHCAs, 4115 (8.3%) observed public OHCAs were analyzed, of which 2500 (60.8%) were shockable. A bystander shock was applied in 18.8% of the shockable arrests. Patients shocked by a bystander were significantly more likely to survive to discharge (66.5% versus 43.0%) and be discharged with favorable functional outcome (57.1% versus 32.7%) than patients initially shocked by emergency medical services. After adjusting for known predictors of outcome, the odds ratio associated with a bystander shock was 2.62 (95% confidence interval, 2.07–3.31) for survival to hospital discharge and 2.73 (95% confidence interval, 2.17–3.44) for discharge with favorable functional outcome. The benefit of bystander shock increased progressively as emergency medical services response time became longer. Conclusions: Bystander automated external defibrillator use before emergency medical services arrival in shockable observed public OHCA was associated with better survival and functional outcomes. Continued emphasis on public automated external defibrillator utilization programs may further improve outcomes of OHCA.

Implementation of an emergency department atrial fibrillation and flutter pathway improves rates of appropriate anticoagulation, reduces length of stay and thirty-day revisit rates for congestive heart failure

OBJECTIVES An evidence-based emergency department (ED) atrial fibrillation and flutter (AFF) pathway was developed to improve care. The primary objective was to measure rates of new anticoagulation (AC) on ED discharge for AFF patients who were not AC correctly upon presentation. METHODS This is a pre-post evaluation from April to December 2013 measuring the impact of our pathway on rates of new AC and other performance measures in patients with uncomplicated AFF solely managed by emergency physicians. A standardized chart review identified demographics, comorbidities, and ED treatments. The primary outcome was the rate of new AC. Secondary outcomes were ED length of stay (LOS), referrals to AFF clinic, ED revisit rates, and 30-day rates of return visits for congestive heart failure (CHF), stroke, major bleeding, and death. RESULTS ED AFF patients totalling 301 (129 pre-pathway [PRE]; 172 post-pathway [POST]) were included; baseline demographics were similar between groups. The rates of AC at ED presentation were 18.6% (PRE) and 19.7% (POST). The rates of new AC on ED discharge were 48.6 % PRE (95% confidence interval [CI] 42.1%-55.1%) and 70.2% POST (62.1%-78.3%) (20.6% [p<0.01; 15.1-26.3]). Median ED LOS decreased from 262 to 218 minutes (44 minutes [p<0.03; 36.2-51.8]). Thirty-day rates of ED revisits for CHF decreased from 13.2% to 2.3% (10.9%; p<0.01; 8.1%-13.7%), and rates of other measures were similar. CONCLUSIONS The evidence-based pathway led to an improvement in the rate of patients with new AC upon discharge, a reduction in ED LOS, and decreased revisit rates for CHF.

Critically appraising noninferiority randomized controlled trials: a primer for emergency physicians.

Noninferiority (NI) trials aim to show that a new treatment or drug is not inferior to a standard, accepted treatment. The rapid proliferation of NI trials within the literature makes it imperative for emergency physicians to be able to read, interpret, and appraise critically this type of research study. Using several emergency medicine examples from the recent literature, this article outlines the key differences between traditional, superiority randomized controlled trials and NI trials. We summarize four important points that an emergency physician should consider when critically appraising an NI trial: 1) Does the new treatment have tangible benefits over the standard treatment? 2) Was the choice of the NI margin appropriate? 3) Was the effect of the standard treatment preserved? Does the trial have assay sensitivity? and 4) What type of analysis strategy was employed: intention-to-treat (ITT) or per protocol (PP)?

Trends in care processes and survival following prehospital resuscitation improvement initiatives for out-of-hospital cardiac arrest in British Columbia, 2006–2016

BACKGROUND British Columbia (BC) Emergency Health Services implemented a strategy to improve outcomes for out-of-hospital cardiac arrest (OHCA), focusing on paramedic-led high-quality on-scene resuscitation. We measured changes in care metrics and survival trends. METHODS This was a post-hoc study of prospectively identified consecutive non-traumatic ambulance-treated adult OHCAs from 2006 to 2016 within BCs four metropolitan areas. The primary outcome was survival to hospital discharge; we also described available favourable neurological outcomes (mRS ≤3). We tested the significance of year-by-year trends in baseline characteristics, and calculated risk-adjusted survival rates using multivariable Poisson regression. RESULTS We included 15 145 patients. In univariate analyses there were significant increases in bystander CPR, chest compression fraction, advanced life support attendance, duration of resuscitation until advanced airway placement, duration of resuscitation until termination, and overall scene time. There was a significant decrease in initial shockable rhythms, bystander witnessed arrests, and transports initiated prior to ROSC. Survival and the proportion of survivors with favourable neurological outcomes increased significantly. In adjusted analyses, there was an improvement in return of spontaneous circulation (risk-adjusted rate 41% in 2006 to 51% in 2016; adjusted rate ratio per year 1.02, 95% CI 1.01-1.02, p < 0.01 for trend) and survival at hospital discharge (risk-adjusted rate 8.6% in 2006 to 16% in 2016; adjusted rate ratio per year 1.05, 95% CI 1.04-1.06, p < 0.01 for trend). CONCLUSION From 2006 to 2016 BCs provincial ambulance system prioritized paramedic-led on-scene resuscitation, during which time there were significant improvements in patient outcomes. Our data may assist other systems, providing a model for prehospital resuscitation quality improvement.

External Validation of the Universal Termination of Resuscitation Rule for Out-of-Hospital Cardiac Arrest in British Columbia

Study objective: The Universal Termination of Resuscitation Rule (TOR Rule) was developed to identify out‐of‐hospital cardiac arrests eligible for field termination of resuscitation, avoiding futile transportation to the hospital. The validity of the rule in emergency medical services (EMS) systems that do not routinely transport out‐of‐hospital cardiac arrest patients to the hospital is unknown. We seek to validate the TOR Rule in British Columbia. Methods: This study included consecutive, nontraumatic, adult, out‐of‐hospital cardiac arrests treated by EMS in British Columbia from April 2011 to September 2015. We excluded patients with active do‐not‐resuscitate orders and those with missing data. Following consensus guidelines, we examined the validity of the TOR Rule after 6 minutes of resuscitation (to approximate three 2‐minute cycles of resuscitation). To ascertain rule performance at the different time junctures, we recalculated TOR Rule classification accuracy at subsequent 1‐minute resuscitation increments. Results: Of 6,994 consecutive, adult, EMS‐treated, out‐of‐hospital cardiac arrests, overall survival was 15%. At 6 minutes of resuscitation, rule performance was sensitivity 0.72, specificity 0.91, positive predictive value 0.98, and negative predictive value 0.36. The TOR Rule recommended care termination for 4,367 patients (62%); of these, 92 survived to hospital discharge (false‐positive rate 2.1%; 95% confidence interval 1.7% to 2.5%); however, this proportion steadily decreased with later application. The TOR Rule recommended continuation of resuscitation in 2,627 patients (38%); of these, 1,674 died (false‐negative rate 64%; 95% confidence interval 62% to 66%). Compared with 6‐minute application, test characteristics at 30 minutes demonstrated nearly perfect positive predictive value (1.0) and specificity (1.0) but a lower sensitivity (0.46) and negative predictive value (0.25). Conclusion: In this cohort of adult out‐of‐hospital cardiac arrest patients, the TOR Rule applied at 6 minutes falsely recommended care termination for 2.1% of patients; however, this decreased with later application. Systems using the TOR Rule to cease resuscitation in the field should consider rule application at points later than 6 minutes.