Grant Innes

Safety and efficiency of emergency department assessment of chest discomfort

Background: Most Canadian emergency departments use an unstructured, individualized approach to patients with chest pain, without data to support the safety and efficiency of this practice. We sought to determine the proportions of patients with chest discomfort in emergency departments who either had acute coronary syndrome (ACS) and were inappropriately discharged from the emergency department or did not have ACS and were held for investigation. Methods: Consecutive consenting patients aged 25 years or older presenting with chest discomfort to 2 urban tertiary care emergency departments between June 2000 and April 2001 were prospectively enrolled unless they had a terminal illness, an obvious traumatic cause, a radiographically identifiable cause, severe communication problems or no fixed address in British Columbia or they would not be available for follow-up by telephone. At 30 days we assigned predefined explicit outcome diagnoses: definite ACS (acute myocardial infarction [AMI] or definite unstable angina) or no ACS. Results: Of 1819 patients, 241 (13.2%) were assigned a 30-day diagnosis of AMI and 157 (8.6%), definite unstable angina. Of these 398 patients, 21 (5.3%) were discharged from the emergency department without a diagnosis of ACS and without plans for further investigation. The clinical sensitivity for detecting ACS was 94.7% (95% confidence interval [CI] 92.5%– 96.9%) and the specificity 73.8% (95% CI 71.5%– 76.0%). Of the patients without ACS or an adverse event, 71.1% were admitted to hospital or held in the emergency department for more than 3 hours. Interpretation: The current individualized approach to evaluation and disposition of patients with chest discomfort in 2 Canadian tertiary care emergency departments misses 5.3% of cases of ACS while consuming considerable health care resources for patients without coronary disease. Opportunities exist to improve both safety and efficiency.

Parenteral dexamethasone for acute severe migraine headache: meta-analysis of randomised controlled trials for preventing recurrence

Objective To examine the effectiveness of parenteral corticosteroids for the relief of acute severe migraine headache and prevention of recurrent headaches. Design Meta-analysis. Data sources Electronic databases (Cochrane Central Register of Controlled Trials, Medline, Embase, LILACS, and CINAHL), conference proceedings, clinical practice guidelines, contacts with industry, and correspondence with authors. Selection criteria Randomised controlled trials in which corticosteroids (alone or combined with standard abortive therapy) were compared with placebo or any other standard treatment for acute migraine in adults. Review methods Two reviewers independently assessed relevance, inclusion, and study quality. Weighted mean differences and relative risks were calculated and are reported with 95% confidence intervals. Results From 666 potentially relevant abstracts, seven studies met the inclusion criteria. All included trials used standard abortive therapy and subsequently compared single dose parenteral dexamethasone with placebo, examining pain relief and recurrence of headache within 72 hours. Dexamethasone and placebo provided similar acute pain reduction (weighted mean difference 0.37, 95% confidence interval −0.20 to 0.94). Dexamethasone was, however, more effective than placebo in reducing recurrence rates (relative risk 0.74, 95% confidence interval 0.60 to 0.90). Side effect profiles between dexamethasone and placebo groups were similar. Conclusion When added to standard abortive therapy for migraine headache, single dose parenteral dexamethasone is associated with a 26% relative reduction in headache recurrence (number needed to treat=9) within 72 hours.

The Role of Triage Liaison Physicians on Mitigating Overcrowding in Emergency Departments: A Systematic Review

OBJECTIVES The objective was to examine the effectiveness of triage liaison physicians (TLPs) on mitigating the effects of emergency department (ED) overcrowding. METHODS Electronic databases (Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Web of Science, HealthSTAR, Dissertation Abstracts, and ABI/INFORM Global), controlled trial registry websites, conference proceedings, study references, contact with experts in the field, and correspondence with authors were used to identify potentially relevant TLP studies. Intervention studies in which a TLP was used to influence ED overcrowding metrics (length of stay [LOS] in minutes, physician initial assessment [PIA], and left without being seen [LWBS]) were included in the review. Two reviewers independently conducted data extraction and assessed the citation relevance, inclusion, and study quality. For continuous outcomes, weighted mean differences (WMD) were calculated and reported with corresponding 95% confidence intervals (CIs). For dichotomous variables, individual and pooled statistics were calculated as relative risk (RR) with 95% CI. RESULTS From 14,446 potentially relevant studies, 28 were included in the systematic review. Thirteen were journal publications, 12 were abstracts, and three were Web-based articles. Most studies employed before-after designs; 23 of the 28 studies were considered of weak quality. Based on the statistical pooling of data from two randomized controlled trials (RCTs), TLP resulted in shorter ED LOS compared to nurse-led triage (WMD = -36.85 min; 95% CI = -51.11 to -22.58). One of these RCTs showed a significant reduction in the PIA associated to TLP presence (WMD = -30.00 min; 95% CI = -56.91 to -3.09); the other RCT showed no change in LWBS due to a CI that included unity (RR = 0.82; 95% CI = 0.67 to 1.00). CONCLUSIONS While the evidence summarized here suggests that to have a TLP is an effective intervention to mitigate the effects of ED overcrowding, due to the weak research methods identified, more research is required before its widespread implementation.

Key indicators of overcrowding in Canadian emergency departments: a Delphi study.

OBJECTIVE To identify the level of consensus among a group of Canadian emergency department (ED) experts on the importance of a set of indicators to document ED overcrowding. METHODS A 2-round Delphi survey was conducted from February 2005 to April 2005, with a multidisciplinary group of 38 Canadian experts in various aspects of ED operations who rated the relevance of 36 measures and ranked their relative importance as indicators of ED overcrowding. RESULTS The response rates for the first and second rounds were 84% and 87%, respectively. The most important indicator identified by the experts was the percentage of the ED occupied by inpatients (mean on a 7-point Likert-type scale 6.53, standard deviation [SD] 0.80). The other 9 indicators, in order of the importance attributed, were the total number of ED patients (mean 6.35, SD 0.75), the total time in the ED (mean 6.16, SD 1.04), the percentage of time that the ED was at or above capacity (mean 6.16, SD 1.08), the overall bed occupancy (mean 6.19, SD 0.93), the time from bed request to bed assignment (mean 6.06, SD 1.08), the time from triage to care (mean 5.84, SD 1.08) the physician satisfaction (mean 5.84, SD 1.22), the time from bed availability to ward transfer (mean 5.53, SD 1.72) and the number of staffed acute care beds (mean 5.53, SD 1.57). CONCLUSION Ten clinically important measures were prioritized by the participants as relevant indicators of ED overcrowding. Indicators derived from consensus techniques have face validity, but their metric properties must be tested to ensure their effectiveness for identifying ED overcrowding in different settings.

The role of triage nurse ordering on mitigating overcrowding in emergency departments: a systematic review

OBJECTIVES The objective was to examine the effectiveness of triage nurse ordering (TNO) on mitigating the effect of emergency department (ED) overcrowding. METHODS Electronic databases (Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, SCOPUS, Web of Science, HealthSTAR, Dissertation Abstracts, ABI/INFORM Global), controlled trial registry websites, conference proceedings, study references, experts in the field, and correspondence with authors were used to identify potentially relevant studies. Interventional studies in which TNO was used to influence ED overcrowding metrics (length of stay [LOS] and physician initial assessment [PIA]) were included in the review. Two reviewers independently assessed study eligibility and methodologic quality. Mean differences were calculated and reported with corresponding 95% confidence intervals (CIs). RESULTS From more than 14,000 potentially relevant studies, 14 were included in the systematic review. Most were single-center ED studies; the overall quality was rated as weak, due to methodologic deficiencies and variable outcome reporting. TNO was associated with a 37-minute mean reduction (95% CI = -44.10 to -30.30 minutes) in the overall ED LOS in one randomized clinical trial (RCT); a 51-minute mean reduction (95% CI = -56.3 to -45.5 minutes) was observed in non-RCTs. When applied to injured subjects with suspected fractures, TNO interventions reduced ED LOS by 20 minutes (95% CI = -37.5 to -1.9 minutes) in three RCTs and by 18 minutes (95% CI = -23.2 to -13.2) in two non-RCTs. No significant reduction in PIA was observed in two RCTs. CONCLUSIONS Overall, TNO appears to be an effective intervention to reduce ED LOS, especially in injury and/or suspected fracture cases. The available evidence is limited by small numbers of studies, weak methodologic quality, and incomplete reporting. Future studies should focus on a better description of the contextual factors surrounding these interventions and exploring the impact of TNO on other indicators of productivity and satisfaction with health care delivery.

Safety and Efficiency of a Chest Pain Diagnostic Algorithm With Selective Outpatient Stress Testing for Emergency Department Patients With Potential Ischemic Chest Pain

STUDY OBJECTIVE Chest pain units have been used to monitor and investigate emergency department (ED) patients with potential ischemic chest pain to reduce the possibility of missed acute coronary syndrome. We seek to optimize the use of hospital resources by implementing a chest pain diagnostic algorithm. METHODS This was a prospective cohort study of ED patients with potential ischemic chest pain. High-risk patients were referred to cardiology, and patients without ECG or biomarker evidence of ischemia were discharged home after 2 to 6 hours of observation. Emergency physicians scheduled discharged patients for outpatient stress ECGs or radionuclide scans at the hospital within 48 hours. Patients with positive provocative test results were immediately referred back to the ED. The primary outcome was the rate of missed diagnosis of acute coronary syndrome at 30 days. RESULTS We prospectively followed 1,116 consecutive patients who went through the chest pain diagnostic algorithm, of whom 197 (17.7%) were admitted at the index visit and 254 (22.8%) received outpatient testing on discharge. The 30-day acute coronary syndrome event rate was 10.8%, and the 30-day missed acute coronary syndrome rate was 0% (95% confidence interval 0% to 2.4%). Of the 120 acute coronary syndrome cases, 99 (82.5%) were diagnosed at the index ED visit, and 21 patients (17.5%) received the diagnosis during outpatient stress testing. CONCLUSION In ED patients with chest pain, a structured diagnostic approach with time-focused ED decision points, brief observation, and selective application of early outpatient provocative testing appears both safe and diagnostically efficient, even though some patients with acute coronary syndrome may be discharged for outpatient stress testing on the index ED visit.

Thirty-day Outcomes of Emergency Department Patients Undergoing Electrical Cardioversion for Atrial Fibrillation or Flutter

OBJECTIVES While the short-term (<7-day) safety and efficiency of electrical cardioversion for emergency department (ED) patients with atrial fibrillation or flutter have been established, the 30-day outcomes with respect to stroke, thromboembolic events, or death have not been investigated. METHODS A two-center cohort of consecutive ED patients undergoing cardioversion for atrial fibrillation or flutter between January 1, 2000, and September 30, 2007, was retrospectively investigated. This cohort was probabilistically linked with both a regional ED database and the provincial health registry to determine which patients had a subsequent ED visit or hospital admission, stroke, or thromboembolic event or died within 30 days. In addition, trained reviewers performed a detailed chart abstraction on 150 randomly selected patients, with emphasis on demographics, vital signs, medical treatment, and predefined adverse events. Hemodynamically unstable patients or those whose condition was the result of an underlying acute medical diagnosis were excluded. Data were analyzed by descriptive methods. RESULTS During the study period, 1,233 patients made 1,820 visits for atrial fibrillation or flutter to the ED. Of the 400 eligible patients undergoing direct-current cardioversion (DCCV), no patients died, had a stroke, or had a thromboembolic event in the following 30 days (95% confidence interval [CI] = 0.0 to 0.8% for all outcomes). A total of 141 patients were included in the formal chart review, with five patients (3.5%, 95% CI = 0.5% to 6.6%) failing cardioversion, six patients (4.3%, 95% CI = 0.9% to 7.6%) having a minor adverse event that did not change disposition, and five patients (3.5%, 95% CI = 0.5% to 6.6%) admitted to hospital at the index visit. CONCLUSIONS Cardioversion of patients with atrial fibrillation or flutter in the ED appears to have a very low rate of long-term complications.

Aminophylline in bradyasystolic cardiac arrest: a randomised placebo-controlled trial

BACKGROUND Endogenous adenosine might cause or perpetuate bradyasystole. Our aim was to determine whether aminophylline, an adenosine antagonist, increases the rate of return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest. METHODS In a double-blind trial, we randomly assigned 971 patients older than 16 years with asystole or pulseless electrical activity at fewer than 60 beats per minute, and who were unresponsive to initial treatment with epinephrine and atropine, to receive intravenous aminophylline (250 mg, and an additional 250 mg if necessary) (n=486) or placebo (n=485). The patients were enrolled between January, 2001 and September, 2003, from 1886 people who had had cardiac arrests. Standard resuscitation measures were used for at least 10 mins after the study drug was administered. Analysis was by intention-to-treat. This trial is registered with the ClinicalTrials.gov registry with the number NCT00312273. FINDINGS Baseline characteristics and survival predictors were similar in both groups. The median time from the arrival of the advanced life-support paramedic team to study drug administration was 13 min. The proportion of patients who had an ROSC was 24.5% in the aminophylline group and 23.7% in the placebo group (difference 0.8%; 95% CI -4.6% to 6.2%; p=0.778). The proportion of patients with non-sinus tachyarrhythmias after study drug administration was 34.6% in the aminophylline group and 26.2% in the placebo group (p=0.004). Survival to hospital admission and survival to hospital discharge were not significantly different between the groups. A multivariate logistic regression analysis showed no evidence of a significant subgroup or interactive effect from aminophylline. INTERPRETATION Although aminophylline increases non-sinus tachyarrhythmias, we noted no evidence that it significantly increases the proportion of patients who achieve ROSC after bradyasystolic cardiac arrest.

Prospective time study derivation of emergency physician workload predictors.

BACKGROUND A reliable emergency department (ED) workload measurement tool would provide a method of quantifying clinical productivity for performance evaluation and physician incentive programs; it would enable health administrators to measure ED outputs; and it could provide the basis for an equitable formula to estimate ED physician staffing requirements. Our objectives were to identify predictors that correlate with physician time needed to treat patients and to develop a multivariable model to predict physician workload. METHODS During 31 day, evening, night and weekend shifts, a research assistant (RA) shadowed 20 emergency physicians, documenting time spent performing clinical and non-clinical functions for 585 patient visits. The RA recorded key predictors including patient gender, age, vital signs and Glasgow Coma Scale (GCS) score, and the mode of arrival, triage level assigned, comorbidity and procedures performed. Multiple linear regression was used to describe the associations between predictor variables and total physician time per patient visit (TPPV), and to derive an equation for physician workload. Model derivation was based on 16 shifts and 314 patient visits; model validation was based on 15 shifts and 271 additional patient visits. RESULTS The strongest predictor variables were: procedure required, triage level, arrival by ambulance, GCS, age, any comorbidity, and number of prior visits. The derived regression equation is: TPPV = 29.7 + 8.6 (procedure required [Yes]) - 3.8 (triage level [1-5]) + 7.1 (ambulance arrival) - 1.1 (GCS [3-15]) + 0.1 (age in years) - 0.05 (n of previous visits) + 3.1 (any comorbidity). This model predicted 31.3% of the variance in physician TPPV (F [12, 29] = 13.2; p < 0.0001). CONCLUSIONS This study clarifies important determinants of emergency physician workload. If validated in other settings, the predictive formula derived and internally validated here is a potential alternative to current simplistic models based solely on patient volume and perceived acuity. An evidence-based workload estimation tool like that described here could facilitate ED productivity measurement, benchmarking, physician performance evaluation, and provide the substrate for an equitable formula to estimate ED physician staffing requirements.

The role of a rapid assessment zone/pod on reducing overcrowding in emergency departments: a systematic review.

Objective To evaluate the effectiveness of a rapid assessment zone (RAZ) to mitigate emergency department (ED) overcrowding. Methods Electronic databases, controlled trial registries, conference proceedings, study references, experts in the field and correspondence with authors were used to identify potentially relevant studies. Intervention studies, in which a RAZ was used to influence length of stay, physician initial assessment and patients left without being seen, were included. Mean differences were calculated and reported with corresponding 95% CIs; individual statistics are presented as RR with associated 95% CI. Results From 14 446 potentially relevant studies, four studies were included in the review. The quality of one study was appraised as moderately high; others were rated as weak. Two studies showed that a RAZ was associated with a reduction of 20 min (95% CI: −47.2 to 7.2) in the ED length of stay; in one non-randomised clinical trial (RCT), a 192 min reduction was reported (95% CI: −211.6 to −172.4). Physician initial assessment showed a reduction of 8.0 min; 95% CI: −13.8 to −2.2 in the RCT and a reduction of 33 min (95% CI: −42.3 to −23.6) and 18 min (95% CI: −22.2 to −13.8) respectively were found in two non-RCTs. There was a reduction in the risk of patient leaving without being seen (RCT: RR=0.93, 95% CI: 0.77 to 1.12; non-RCT: RR =0.68, 95% CI: 0.63 to 0.73). Conclusions Although the results are consistent, and low acuity patients seem to benefit the most from a RAZ, the available evidence to support its implementation is limited.