Which Patients Should Have Early Surgical Intervention for Acute Ureteral Colic?

PURPOSE: Early surgical intervention is an attractive option for acute ureteral colic but existing evidence does not clarify which patients benefit. We compared treatment failure rates in patients receiving early intervention and patients offered spontaneous passage to identify subgroups that benefit from early intervention. MATERIALS AND METHODS: We used administrative data and structured chart review to study consecutive patients attending 9 emergency departments in 2 Canadian provinces with confirmed 2.0 to 9.9 mm ureteral stones. We described patient, stone and treatment characteristics, and performed multivariable regression to identify factors associated with treatment failure, defined as intervention or hospitalization within 60 days. Our secondary outcome was emergency department revisit rate. RESULTS: Overall 1,168 of 3,081 patients underwent early intervention. Those with stones smaller than 5 mm experienced more treatment failures (31.5% vs 9.9%, difference 21.6%, 95% CI 16.9 to 21.2) and emergency department revisits (38.5% vs 19.7%, difference 18.8%, 95% CI 13.8 to 23.8) with early intervention than with spontaneous passage. Patients with stones 7.0 mm or larger experienced fewer treatment failures (34.7% vs 58.6%, risk difference 23.9%, 95% CI 11.3 to 36.6) and similar emergency department revisit rates with early intervention. Patients with 5.0 to 6.9 mm stones had fewer treatment failures with intervention (37.4% vs 55.5%, risk difference 18.1%, 95% CI 7.1 to 28.9) if stones were in the proximal or middle ureter. CONCLUSIONS: Early intervention improves outcomes for patients with large (greater than 7 mm) ureteral stones or 5 to 7 mm proximal or mid ureteral stones. Early intervention may increase morbidity for patients with stones smaller than 5 mm. These findings could help inform future guidelines.

Can plain film radiography improve the emergency department detection of clinically important urinary stones?

OBJECTIVE: Physicians frequently use ultrasound to assess hydronephrosis in patients with suspected renal colic, but ultrasound has limited diagnostic sensitivity and rarely clarifies stone size or location. Consequently, up to 80% of emergency department (ED) renal colic patients undergo confirmatory CT imaging. Our goal was to estimate x-ray sensitivity for urinary stones and determine whether x-ray substantially improves stone detection (sensitivity) compared to hydronephrosis assessment alone. METHODS: We reviewed imaging reports from all renal colic patients who underwent x-ray and CT at four EDs. For each patient, we documented stone size, location and hydronephrosis severity on CT and whether stones were identified on x-ray. We considered moderate and severe hydronephrosis (MS-Hydro) as significant positive findings, then calculated the sensitivity (detection rate) of MS-Hydro and x-ray for large stones ≥5 mm and for stones likely to require intervention (all ureteral stones >7 mm and proximal or middle stones >5 mm). We then tested a diagnostic algorithm adding x-ray to hydronephrosis assessment. RESULTS: Among 1026 patients with 1527 stones, MS-Hydro sensitivity was 39% for large stones and 60% for interventional stones. X-ray sensitivity was 46% for large stones and 52% for interventional stones. Adding x-ray to hydronephrosis assessment increased sensitivity in all stone categories, specifically from 39% to 68% for large stones (gain = 29%; 95%CI, 23% to 35%) and from 60% to 82% for interventional stones (gain = 22%; 95%CI, 13% to 30%). Because CT and ultrasound show strong agreement for MS-Hydro identification, physicians who depend on ultrasound-based hydronephrosis assessment could achieve similar gains by adding x-ray. CONCLUSIONS: Adding x-ray to hydronephrosis assessment substantially improves diagnostic sensitivity, enabling the detection of nearly 70% of large stones and over 80% of interventional stones. This level of sensitivity may be sufficient to reassure physicians about a renal colic diagnosis without CT imaging for many patients.

The impact of high-sensitivity troponin implementation on hospital operations and patient outcomes in 3 tertiary care centers.

OBJECTIVE: High-sensitivity troponin T (hs-TnT) assays detect myocardial injury sooner, possibly improving throughput times for emergency department (ED) assessment of suspected acute myocardial infarction (AMI). This study evaluates the influence of hs-TnT implementation on ED length of stay (LOS), consultations and admissions, as well as ED revisits with cardiology admissions for patients undergoing testing for suspected AMI. METHODS: This control pre-post design analysis included patients evaluated using hs-TnT or conventional troponin T. Data were collected from 3 ED databases for patients who had a troponin assay for suspected AMI for the periods February 12, 2011-April 22, 2011 (Ctrl); November 20, 2011-January 28, 2012 (Pre); and February 12, 2012-April 21, 2012 (Post). The primary outcome was ED LOS; secondary outcomes included the proportions of patients who received ED cardiology consultations, patients who were admitted to hospital, and discharged patients who revisited the ED within 30 days. RESULTS: Data were analyzed from 6650 (Ctrl), 6866 (Pre), and 5754 (Post) patients. Median ED LOS decreased following hs-TnT implementation (6.60 hours in Ctrl and Pre vs 6.10 hours in Post, P < .001). There was no change in cardiology consultations or admissions following hs-TnT implementation. Fewer ED revisits occurred within 30 days in Post (16.0% Ctrl, 16.5% Pre vs 14.9% Post; P < .01). These results were preserved after adjusting for age and Canadian Triage Acuity Score. CONCLUSIONS: This hs-TnT implementation strategy, using an equivalent cutoff for the conventional troponin T and hs-TnT assays, decreased ED LOS for patients with suspected AMI and did not increase cardiology resource utilization or ED revisits.

Emergency medical services response time and mortality in an urban setting.

BACKGROUND: A common tenet in emergency medical services (EMS) is that faster response equates to better patient outcome, translated by some EMS operations into a goal of a response time of 8 minutes or less for advanced life support (ALS) units responding to life-threatening events. OBJECTIVE: To explore whether an 8-minute EMS response time was associated with mortality. METHODS: This was a one-year retrospective cohort study of adults with a life-threatening event as assessed at the time of the 9-1-1 call (Medical Priority Dispatch System Echo- or Delta-level event). The study setting was an urban all-ALS EMS system serving a population of approximately 1 million. Response time was defined as 9-1-1 call receipt to ALS unit arrival on scene, and outcome was defined as all-cause mortality at hospital discharge. Potential covariates included patient acuity, age, gender, and combined scene and transport interval time. Stratified analysis and logistic regression were used to assess the response time-mortality association. RESULTS: There were 7,760 unit responses that met the inclusion criteria; 1,865 (24%) were ≥8 minutes. The average patient age was 56.7 years (standard deviation = 21.5). For patients with a response time ≥8 minutes, 7.1% died, compared with 6.4% for patients with a response time ≤7 minutes 59 seconds (risk difference 0.7%; 95% confidence interval [CI]: -0.5%, 2.0%). The adjusted odds ratio of mortality for ≥8 minutes was 1.19 (95% CI: 0.97, 1.47). An exploratory analysis suggested there may be a small beneficial effect of response ≤7 minutes 59 seconds for those who survived to become an inpatient (adjusted odds ratio = 1.30; 95% CI: 1.00, 1.69). CONCLUSIONS: These results call into question the clinical effectiveness of a dichotomous 8-minute ALS response time on decreasing mortality for the majority of adult patients identified as having a life-threatening event at the time of the 9-1-1 call. However, this study does not suggest that rapid EMS response is undesirable or unimportant for certain patients. This analysis highlights the need for further research on who may benefit from rapid EMS response, whether these individuals can be identified at the time of the 9-1-1 call, and what the optimum response time is.

A comparative evaluation of the strengths of association between different emergency department crowding metrics and repeat visits within 72 hours.

OBJECTIVE: We sought to compare strengths of association among multiple emergency department (ED) input, throughput and output metrics and the outcome of 72-h ED re-visits. METHODS: This database analysis used healthcare administrative data from three urban, university-affiliated EDs in Calgary, Canada, calendar years 2010-2014. We used data from all patients presenting to participating EDs during the study period, and the primary analysis was performed on patients discharged from the ED. Regression models quantified the association between input, throughput and output metrics and the risk of return ED visit within 72 h of discharge from the index ED encounter. Strength of association between the crowding metrics and 72-h ED re-visits was compared using Akaike's Information Criterion. RESULTS: The findings of this study are based on data from 845,588 patient encounters ending in discharge. The input metric with the strongest association with 72-h re-visits was median ED waiting time. The throughput metric with the strongest association with 72-h re-visits was the ED occupancy. The output metric with the strongest association with 72-h re-visits was the median inpatient boarding time. CONCLUSION: Input, throughput and output metrics are all associated with 72-h re-visits. Delays in any of these operational phases have detrimental effects on patient outcomes. ED waiting time, ED occupancy, and boarding times are the most meaningful input, throughput and output metrics. These should be the preferred metrics for quantifying ED crowding in research and quality improvement efforts, and for clinicians to monitor ED crowding in real time.

RéSUMé: OBJECTIF: Nous avons cherché à comparer la force de l'association entre plusieurs paramètres d'entrée, de débit et de sortie des services d'urgence (SU) et l'issue des nouvelles visites aux SU après 72 heures. MéTHODES: Cette analyse de base de données a utilisé des données administratives sur les soins de santé de trois services d'urgence urbains affiliés à une université à Calgary, au Canada, pour les années civiles 2010-2014. Nous avons utilisé les données de tous les patients se présentant aux urgences participantes pendant la période de l'étude, et l'analyse primaire a porté sur les patients sortis des urgences. Des modèles de régression ont quantifié l'association entre les paramètres d'entrée, de débit et de sortie et le risque d'une nouvelle visite aux urgences dans les 72 heures suivant la sortie des urgences de référence. La force de l'association entre les paramètres d'encombrement et les réadmissions aux urgences à 72 heures a été comparée à l'aide du critère d'information d'Akaike. RéSULTATS: Les résultats de cette étude sont basés sur les données de 845 588 rencontres de patients se terminant par une sortie. La mesure d'entrée présentant la plus forte association avec les nouvelles visites dans les 72 heures était le temps d'attente médian aux urgences. La mesure du débit avec la plus forte association avec les visites répétées de 72 heures était l'occupation par le SU. La métrique de sortie présentant la plus forte association avec les revisites à 72 heures était la durée médiane d'embarquement des patients hospitalisés. CONCLUSIONS: Les mesures d'entrée, de débit et de sortie sont toutes associées aux revisites de 72 heures. Les retards dans l'une de ces phases opérationnelles ont des effets néfastes sur les résultats pour les patients. Le temps d'attente aux urgences, le taux d'occupation des urgences et le temps d'embarquement sont les paramètres les plus significatifs en termes d'entrée, de débit et de sortie. Ces paramètres devraient être privilégiés pour quantifier l'encombrement des urgences dans le cadre de la recherche et des efforts d'amélioration de la qualité, et pour permettre aux cliniciens de surveiller l'encombrement des urgences en temps réel.

The CCEDRRN COVID-19 Mortality Score to predict death among nonpalliative patients with COVID-19 presenting to emergency departments: a derivation and validation study.

BACKGROUND: Predicting mortality from COVID-19 using information available when patients present to the emergency department can inform goals-of-care decisions and assist with ethical allocation of critical care resources. The study objective was to develop and validate a clinical score to predict emergency department and in-hospital mortality among consecutive nonpalliative patients with COVID-19; in this study, we define palliative patients as those who do not want resuscitative measures, such as intubation, intensive care unit care or cardiopulmonary resuscitation. METHODS: This derivation and validation study used observational cohort data recruited from 46 hospitals in 8 Canadian provinces participating in the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN). We included adult (age ≥ 18 yr) nonpalliative patients with confirmed COVID-19 who presented to the emergency department of a participating site between Mar. 1, 2020, and Jan. 31, 2021. We randomly assigned hospitals to derivation or validation, and prespecified clinical variables as candidate predictors. We used logistic regression to develop the score in a derivation cohort and examined its performance in predicting emergency department and in-hospital mortality in a validation cohort. RESULTS: Of 8761 eligible patients, 618 (7.0%) died. The CCEDRRN COVID-19 Mortality Score included age, sex, type of residence, arrival mode, chest pain, severe liver disease, respiratory rate and level of respiratory support. The area under the curve was 0.92 (95% confidence interval [CI] 0.90-0.93) in derivation and 0.92 (95% CI 0.90-0.93) in validation. The score had excellent calibration. These results suggest that scores of 6 or less would categorize patients as being at low risk for in-hospital death, with a negative predictive value of 99.9%. Patients in the low-risk group had an in-hospital mortality rate of 0.1%. Patients with a score of 15 or higher had an observed mortality rate of 81.0%. INTERPRETATION: The CCEDRRN COVID-19 Mortality Score is a simple score that can be used for level-of-care discussions with patients and in situations of critical care resource constraints to accurately predict death using variables available on emergency department arrival. The score was derived and validated mostly in unvaccinated patients, and before variants of concern were circulating widely and newer treatment regimens implemented in Canada. STUDY REGISTRATION: ClinicalTrials.gov, no. NCT04702945.

Does early intervention improve outcomes for patients with acute ureteral colic?

OBJECTIVES: Early surgical intervention is increasingly employed for patients with ureteral colic, but guidelines and current practice are variable. We compared 60-day outcomes for matched patients undergoing early intervention vs. spontaneous passage. METHODS: This multicentre propensity-matched cohort analysis used administrative data and chart review to study all eligible emergency department (ED) patients with confirmed 2.0-9.9 mm ureteral stones. Those having planned stone intervention within 5 days comprised the intervention cohort. Controls attempting spontaneous passage were matched to intervention patients based on age, sex, stone width, stone location, hydronephrosis, ED site, ambulance arrival and acuity level. The primary outcome was treatment failure, defined as rescue intervention or hospitalization within 60 days, using a time to event analysis. Secondary outcome was ED revisit rate. RESULTS: Among 1154 matched patients, early intervention did not reduce the risk of treatment failure (adjusted hazard ratio 0.94; P = 0.61). By 60 days, 21.8% of patients in both groups experienced the composite primary outcome (difference 0.0%; 95% confidence interval - 4.8 to 4.8%). Intervention patients required more hospitalizations (20.1% vs. 12.8%; difference 7.3%; 95% CI 3.0-11.5%) and ED revisits (36.1% vs. 25.5%; difference 10.6%; 95% CI 5.3-15.9%), but (insignificantly) fewer rescue interventions (18.9% vs. 21.3%; difference - 2.4%; 95% CI - 7.0 to 2.2%). CONCLUSIONS: In matched patients with 2.0-9.9 mm ureteral stones, early intervention was associated with similar rates of treatment failure but greater patient morbidity, evidenced by hospitalizations and emergency revisits. Physicians should adopt a selective approach to interventional referral and consider that spontaneous passage probably provides better outcomes for many low-risk patients.

RéSUMé: OBJECTIFS: L'intervention chirurgicale précoce est de plus en plus utilisée pour les patients atteints de coliques urétérales, mais les lignes directrices et la pratique actuelle sont variables. Nous avons comparé les résultats à 60 jours pour les patients appariés subissant une intervention précoce par rapport au passage spontané. LES MéTHODES: Cette analyse de cohorte multicentrique par appariement de propension a utilisé des données administratives et l'examen des dossiers pour étudier tous les patients admissibles des services d'urgence (ED) ayant des calculs urétéraux confirmés de 2,0-9,9 mm Ceux qui avaient planifié une intervention de calcul dans les cinq jours constituaient la cohorte d'intervention. Les témoins tentant de passer spontanément ont été appariés aux patients d'intervention en fonction de l'âge, du sexe, de la largeur du calcul, de l'emplacement du calcul, de l'hydronéphrose, du site de l'urgence, de l'arrivée de l'ambulance et du niveau d'acuité. Le résultat principal était l'échec de traitement, défini comme l'intervention de sauvetage ou l'hospitalisation dans les 60 jours, utilisant un temps à l'analyse d'événement. Le résultat secondaire était le taux de revisite à l'urgence RéSULTATS: Sur 1154 patients appariés, une intervention précoce n'a pas réduit le risque d'échec du traitement (ratio de risque ajusté = 0,94 ; P = 0,61). Au bout de 60 jours, 21,8 % des patients des deux groupes avaient atteint le résultat primaire composite (différence = 0,0 % ; intervalle de confiance à 95 % -4,8 % à 4,8 %). Les patients d'intervention ont nécessité plus d'hospitalisations (20,1 % contre 12,8 % ; différence = 7,3 % ; IC 95 %, 3,0 à 11,5 %) et de nouvelles visites à l'urgence (36,1 % contre 25,5 % ; différence = 10,6 % ; IC 95 %, 5,3 à 15,9 %), mais (de manière non significative) moins d'interventions de sauvetage (18,9 % contre 21,3 % ; différence = 2,4 % ; IC 95 %, -7,0 à 2,2 %). CONCLUSIONS: Chez des patients appariés présentant des calculs urétéraux de 2,0 à 9,9 mm, l'intervention précoce a été associée à des taux similaires d'échec du traitement mais à une morbidité plus importante des patients, comme en témoignent les hospitalisations et les revisites aux urgences. Les médecins devraient adopter une approche sélective de l'orientation interventionnelle et considérer que le passage spontané offre probablement de meilleurs résultats pour de nombreux patients à faible risque.

Hydronephrosis severity clarifies prognosis and guides management for emergency department patients with acute ureteral colic.

OBJECTIVE: In emergency department patients with ureteral colic, the prognostic value of hydronephrosis is unclear. Our goal was to determine whether hydronephrosis can differentiate low-risk patients appropriate for trial of spontaneous passage from those with clinically important stones likely to experience passage failure. METHODS: We used administrative data and structured chart review to evaluate a consecutive cohort of patients with ureteral stones who had a CT at nine Canadian hospitals in two cities. We used CT, the gold standard for stone imaging, to assess hydronephrosis and stone size. We described classification accuracy of hydronephrosis severity for detecting large (≥ 5 mm) stones. In patients attempting spontaneous passage we used hierarchical Bayesian regression to determine the association of hydronephrosis with passage failure, defined by the need for rescue intervention within 60 days. To illustrate prognostic utility, we reported pre-test probability of passage failure among all eligible patients (without hydronephrosis guidance) to post-test probability of passage failure in each hydronephrosis group. RESULTS: Of 3251 patients, 70% male and mean age 51, 38% had a large stone, including 23%, 29%, 53% and 72% with absent, mild, moderate and severe hydronephrosis. Passage failure rates were 15%, 20%, 28% and 43% in the respective hydronephrosis categories, and 23% overall. "Absent or mild" hydronephrosis identified a large subset of patients (64%) with low passage failure rates. Moderate hydronephrosis predicted slightly higher, and severe hydronephrosis substantially higher passage failure risk. CONCLUSIONS: Absent and mild hydronephrosis identify low-risk patients unlikely to experience passage failure, who may be appropriate for trial of spontaneous passage without CT imaging. Moderate hydronephrosis is weakly associated with larger stones but not with significantly greater passage failure. Severe hydronephrosis is an important finding that warrants definitive imaging and referral. Differentiating "moderate-severe" from "absent-mild" hydronephrosis provides risk stratification value. More granular hydronephrosis grading is not prognostically helpful.

RéSUMé: OBJECTIF: Chez les patients des services d'urgence (SU) atteints de colique urétérale, la valeur pronostique de l'hydronéphrose n'est pas claire. Notre objectif était de déterminer si l'hydronéphrose peut différencier les patients à faible risque appropriés pour l'essai de passage spontané de ceux qui ont des calculs cliniquement importants susceptibles de subir un échec de passage. MéTHODES: Nous avons utilisé des données administratives et un examen structuré des dossiers pour évaluer une cohorte consécutive de patients atteints de calculs urétéraux qui avaient subi une tomodensitométrie dans neuf hôpitaux canadiens de deux villes. Nous avons utilisé la tomodensitométrie, l'étalon-or pour l'imagerie des calculs, pour évaluer l'hydronéphrose et la taille des calculs. Nous avons décrit la précision de la classification de la gravité de l'hydronéphrose pour la détection de gros calculs (> 5 mm). Chez les patients tentant un passage spontané, nous avons utilisé la régression bayésienne hiérarchique pour déterminer l'association de l'hydronéphrose avec l'échec du passage, défini par le besoin d'intervention de sauvetage dans les 60 jours. Pour illustrer l'utilité pronostique, nous avons signalé la probabilité d'échec de passage avant le test chez tous les patients admissibles (sans directives sur l'hydronéphrose) à la probabilité d'échec de passage post-test dans chaque groupe d'hydronéphrose. RéSULTATS: Sur 3251 patients, 70% d'hommes et d'âge moyen 51 ans, 38% avaient un gros calcul, dont 23%, 29%, 53% et 72% avec une hydronéphrose absente, légère, modérée et sévère. Les taux d'échec au passage étaient de 15%, 20%, 28% et 43% dans les catégories d'hydronéphrose respectives et de 23% dans l'ensemble. L'hydronéphrose « absente ou légère ¼ a permis d'identifier un sous-ensemble important de patients (64%) présentant de faibles taux d'échec au passage. Une hydronéphrose modérée prédisait un risque d'échec de passage légèrement plus élevé, et une hydronéphrose sévère un risque sensiblement plus élevé. CONCLUSIONS: L'absence d'hydronéphrose et une hydronéphrose légère permettent d'identifier les patients à faible risque, peu susceptibles d'avoir un échec de passage, qui peuvent être appropriés pour un essai de passage spontané sans imagerie CT. Une hydronéphrose modérée est faiblement associée à des calculs plus gros mais pas à un échec de passage significativement plus important. L'hydronéphrose sévère est une constatation importante qui justifie une imagerie définitive et une référence. Différencier l'hydronéphrose « modérée-sévère ¼ de l'« absence-légère ¼ fournit une valeur de stratification du risque. Un classement plus granulaire de l'hydronéphrose n'est pas utile sur le plan pronostique.

Emergency overcrowding and access block: A smaller problem than we think.

OBJECTIVES: Emergency department (ED) access block, the inability to provide timely care for high acuity patients, is the leading safety concern in First World EDs. The main cause of ED access block is hospital access block with prolonged boarding of inpatients in emergency stretchers. Cumulative emergency access gap, the product of the number of arriving high acuity patients and their average delay to reach a care space, is a novel access measure that provides a facility-level estimate of total emergency care delays. Many health leaders believe these delays are too large to be solved without substantial increases in hospital capacity. Our objective was to quantify cumulative emergency access blocks (the problem) as a fraction of inpatient capacity (the potential solution) at a large sample of Canadian hospitals. METHODS: In this cross-sectional study, we collated 2015 administrative data from 25 Canadian hospitals summarizing patient inflow and delays to ED care space. Cumulative access gap for high acuity patients was calculated by multiplying the number of Canadian Triage Acuity Scale (CTAS) 1-3 patients by their average delay to reach a care space. We compared cumulative ED access gap to available inpatient bed hours to estimate fractional access gap. RESULTS: Study sites included 16 tertiary and 9 community EDs in 12 cities, representing 1.79 million patient visits. Median ED census (interquartile range) was 66,300 visits per year (58,700-80,600). High acuity patients accounted for 70.7% of visits (60.9%-79.0%). The mean (SD) cumulative ED access gap was 46,000 stretcher hours per site per year (± 19,900), which was 1.14% (± 0.45%) of inpatient capacity. CONCLUSION: ED access gaps are large and jeopardize care for high acuity patients, but they are small relative to hospital operating capacity. If access block were viewed as a "whole hospital" problem, capacity or efficiency improvements in the range of 1% to 3% could profoundly mitigate emergency care delays.

Impact of physician payment mechanism on emergency department operational performance.

OBJECTIVE: Fee-for-service payment may motivate physicians to see more patients and achieve higher productivity. In 2015, emergency physicians at one Vancouver hospital switched to fee-for-service payment, while those at a sister hospital remained on contract, creating a natural experiment where the compensation method changed, but other factors remained constant. Our hypothesis was that fee-for-service payment would increase physician efficiency and reduce patient wait times. METHODS: This interrupted time series with concurrent control analysed emergency department (ED) performance during a 42-week period, encompassing the intervention (fee for service). Data were aggregated by week and plotted in a time series fashion. We adjusted for autocorrelation and developed general linear regression models to assess level and trend changes. Our primary outcome was the wait time to physician. RESULTS: Data from 142,361 ED visits were analysed. Baseline wait times rose at both sites during the pre-intervention phase. Immediately post-intervention, the median wait time increased by 2.4 minutes at the control site and fell by 7.2 minutes at the intervention site (difference=9.6 minutes; 95% confidence interval, 2.9-16.4; p=0.007). The wait time trend (slope) subsequently deteriorated by 0.5 minutes per week at the intervention site relative to the expected counterfactual (p for the trend difference=0.07). By the end of the study, cross-site differences had not changed significantly from baseline. CONCLUSION: Fee-for-service payment was associated with a 9.6-minute (24%) reduction in wait time, compatible with an extrinsic motivational effect; however, this was not sustained, and the intervention had no impact on other operational parameters studied. Physician compensation is an important policy issue but may not be a primary determinant of ED operational efficiency.

Age-adjusted D-dimer thresholds in the investigation of suspected pulmonary embolism: A retrospective evaluation in patients ages 50 and older using administrative data.

OBJECTIVES: D-dimer testing is an important component of the workup for pulmonary embolism (PE). However, age-related increases in D-dimer concentrations result in false positives in older adults, leading to potentially unnecessary imaging utilization. The objective of this study was to quantify the test characteristics of an age-adjusted D-dimer cut-off for ruling out PE in older patients investigated in actual clinical practice. METHODS: This observational study used administrative data from four emergency departments from July 2013 to January 2015. Eligible patients were ages 50 and older with symptoms of PE who underwent D-dimer testing. The primary outcome was 30-day diagnosis of PE, confirmed by imaging reports. Test characteristics of the D-dimer assay were calculated using the standard reference value (500 ng/ml), the local reference value (470 ng/ml), and an age-adjusted threshold (10 ng/ml × patient's age). RESULTS: This cohort includes 6,655 patients ages 50 and older undergoing D-dimer testing for a possible PE. Of these, 246 (3.7%) were diagnosed with PE. Age-adjusted D-dimer cut-offs were more specific than standard cut-offs (75.4% v. 63.8%) but less sensitive (90.3% v. 97.2%). The false-negative risk in this population was 0.49% using age-adjusted D-dimer cut-offs compared with 0.15% with traditional cut-offs. CONCLUSION: Age-adjusted D-dimer cut-offs are substantially more specific than traditional cut-offs and may reduce CT utilization among older patients with suspected PE. We observed a loss of sensitivity, with an increased risk of false-negatives, using age-adjusted cut-offs. We encourage further evaluation of the safety and accuracy of age-adjusted D-dimer cut-offs in actual clinical practice.

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.

Tissue plasminogen activator in cardiac arrest with pulseless electrical activity.

BACKGROUND: Coronary thrombosis and pulmonary thromboembolism are common causes of cardiac arrest. We assessed whether the administration of tissue plasminogen activator (t-PA) during cardiopulmonary resuscitation would benefit patients with cardiac arrest and pulseless electrical activity of unknown or presumed cardiovascular cause. METHODS: Patients who were older than 16 years of age and who had more than one minute of pulseless electrical activity that was unresponsive to initial therapy outside the hospital or in the emergency department were eligible. Patients were randomly assigned to receive 100 mg of t-PA or placebo intravenously over a 15-minute period in a double-blind fashion. Standard resuscitation was then continued for at least 15 minutes. The primary outcome was survival to hospital discharge. RESULTS: During the study period, 1583 patients with cardiac arrest were treated and 233 patients were enrolled (117 in the t-PA group and 116 in the placebo group). The characteristics of the patients in the two groups were similar. One patient in the t-PA group survived to hospital discharge, as compared with none in the placebo group (absolute difference between groups, 0.9; 95 percent confidence interval, -2.6 to 4.8; P=0.99). The proportion of patients with return of spontaneous circulation was 21.4 percent in the t-PA group and 23.3 percent in the placebo group (absolute difference between groups, -1.9; 95 percent confidence interval, -12.6 to 8.8; P=0.85). CONCLUSIONS: We found no evidence of a beneficial effect of fibrinolysis in patients with cardiac arrest and pulseless electrical activity of unknown or presumed cardiovascular cause. Our study had limited statistical power, and it remains unknown whether there is a small treatment effect or whether selected subgroups may benefit.

Sex-related Differences in Emergency Department Renal Colic Management: Females Have Fewer Computed Tomography Scans but Similar Outcomes.

BACKGROUND: Sex-related differences occur in many areas of medicine. Emergency department (ED) studies have suggested differences in access to care, diagnostic imaging use, pain management, and intervention. We investigated sex-based differences in the care and outcomes for ED patients with acute renal colic. METHODS: This was a multicenter population-based retrospective observational cohort study using administrative data and supplemented by structured chart review. All patients seen in Calgary Health Region EDs between January 1 and December 31, 2014, with an ED diagnosis of renal colic based on the following ICD-10 codes were eligible for inclusion: calculus of kidney (N200), calculus of ureter (N201), calculus of kidney with calculus of ureter (N202), hydronephrosis with renal and ureteral calculous obstruction (N132), unspecified renal colic (N23), and unspecified urinary calculus (N209). ED visit data and test results were accessed in the regional ED clinical database. Stone characteristics were captured from diagnostic imaging reports. Regional hospital databases were used to identify subsequent ED encounters, hospital admissions, and surgical procedures within 60 days. Outcomes were stratified by sex. The primary outcome, intended as a marker of overall effectiveness of ED care, was the unscheduled 7-day ED revisit rate among patients who were discharged home after their index ED visit. Secondary outcomes included ED pain management as reflected by administration of narcotics or intravenous nonsteroidals, the performance of advanced imaging-either ultrasound (US) or computed tomography (CT), and the proportion of patients who required hospitalization or surgical intervention within 60 days. RESULTS: From January 1 to December 31, 2014, a total of 3,104 eligible patients were studied: 1,111 women (35.8%) and 1,993 men (64.2%). Baseline characteristics, access times, analgesic use, and admission rates were similar in both groups. Men were more likely to have CT (68.9% vs. 58.5%, difference = 10.4%, 95% confidence interval [CI] = 6.8 to 14.0) while women were more likely to have US (20.8% vs. 9.6%, difference = 11.2%, 95% CI = 8.4 to 13.9). At 7 days, 17.9% of women and 19.0% of men who were discharged after their index ED visit required an ED revisit (difference = 1.1%, 95% CI = -2.8 to 4.9). Men were more likely to be hospitalized at 7 days (9.8% vs. 6.5%, difference = 3.3%, 95% CI = 0.6 to 6.0). CONCLUSION: This study shows greater reliance on US in females but no other sex-specific differences in the management of ED patients with acute renal colic. Higher CT use in men was not associated with improved outcomes, and we found no important differences in access to care, diagnostic or treatment intensity, or revisit rates as a marker of care effectiveness.

Parenteral dihydroergotamine for acute migraine headache: a systematic review of the literature.

STUDY OBJECTIVE: Many therapies are used in the treatment of acute migraine headache, with little agreement on effectiveness. This systematic review is designed to determine the effectiveness of parenteral dihydroergotamine in reducing pain, nausea, and relapse for episodes of acute migraine in adults. METHODS: Randomized controlled trials were identified using MEDLINE, EMBASE, other computerized databases, hand searching, bibliographies, and contacts with industry and authors. Studies in which dihydroergotamine (alone or in combination with an antiemetic) was compared with placebo or any other common migraine therapy were considered. Relevance, inclusion, and study quality were assessed independently by 2 reviewers. RESULTS: From 281 potentially relevant abstracts, 11 studies met the inclusion criteria. Solitary dihydroergotamine use was compared to sumatriptan and phenothiazines in 3 studies; results failed to demonstrate a significant benefit of dihydroergotamine over these therapies. In 8 combination treatment studies, heterogeneity in study methodology prevented statistical pooling. However, dihydroergotamine administered with an antiemetic was as effective as or more effective than meperidine, valproate, or ketorolac across all pain, nausea, and relapse outcomes reported in all studies. CONCLUSION: This evidence suggests that dihydroergotamine is not as effective as sumatriptan or phenothiazines as a single agent for treatment of acute migraine headache; however, when administered with an antiemetic, dihydroergotamine appears to be as effective as opiates, ketorolac, or valproate. Given its nonnarcotic properties, parenteral dihydroergotamine combined with an antiemetic should be considered as effective initial therapy in clinical practice.

Basic pharmacology and advances in emergency medicine.

To provide optimal pain control for their patients, emergency physicians should have an in-depth understanding of analgesic drugs and how to use and combine them effectively. The purpose of this article is to describe the pharmacology and use of analgesic agents that are most useful in the management of acute pain in the emergency department.

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.