RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial: Study rationale and design.

Out-of-hospital cardiac arrest (OHCA) occurs in nearly 350,000 people each year in the United States (US). Despite advances in pre and in-hospital care, OHCA survival remains low and is highly variable across systems and regions. The critical barrier to improving cardiac arrest outcomes is not a lack of knowledge about effective interventions, but rather the widespread lack of systems of care to deliver interventions known to be successful. The RAndomized Cluster Evaluation of Cardiac ARrest Systems (RACE-CARS) trial is a 7-year pragmatic, cluster-randomized trial of 62 counties (57 clusters) in North Carolina using an established registry and is testing whether implementation of a customized set of strategically targeted community-based interventions improves survival to hospital discharge with good neurologic function in OHCA relative to control/standard care. The multifaceted intervention comprises rapid cardiac arrest recognition and systematic bystander CPR instructions by 9-1-1 telecommunicators, comprehensive community CPR training and enhanced early automated external defibrillator (AED) use prior to emergency medical systems (EMS) arrival. Approximately 20,000 patients are expected to be enrolled in the RACE CARS Trial over 4 years of the assessment period. The primary endpoint is survival to hospital discharge with good neurologic outcome defined as a cerebral performance category (CPC) of 1 or 2. Secondary outcomes include the rate of bystander CPR, defibrillation prior to arrival of EMS, and quality of life. We aim to identify successful community- and systems-based strategies to improve outcomes of OHCA using a cluster randomized-controlled trial design that aims to provide a high level of evidence for future application.

The association between ambulance hospital turnaround times and patient acuity, destination hospital, and time of day.

INTRODUCTION: The availability of ambulances to respond to emergency calls is related to their ability to return to service from the hospital. Extended hospital turnaround times decrease the number of available unit hours ambulances are deployed, which in turn can increase coverage costs or sacrifice coverage. OBJECTIVE: To determine whether ambulance turnaround times were associated with patient acuity, destination hospital, and time of day. METHODS: This retrospective analysis of ambulance hospital turnaround times utilized 12 months of data from a single, countywide, metropolitan emergency medical services (EMS) service. Turnaround time was defined as the interval between the time of ambulance arrival at the hospital and the time the ambulance became available to respond to another call. Independent variables included patient acuity (low [BLS nonemergency transport], medium [ALS care and nonemergency transport], and high [ALS care and emergency transport]), destination hospital (seven regional hospitals), and time of day (one-hour intervals). Data analysis consisted of descriptive statistics, t-tests, and linear regression. RESULTS: Of the 61,094 patient transports, the mean turnaround time was 35.6 minutes (standard deviation [SD] = 16.5). Turnaround time was significantly associated with patient acuity (p < 0.001). High-acuity calls had a mean turnaround time of 52.5 minutes (SD = 21.5), whereas moderate-acuity and low-acuity calls had mean turnaround times of 42.0 minutes (SD = 16.4) and 32.5 minutes (SD = 14.4), respectively. A statistically significant relationship between destination hospital and turnaround time was found, with the differences in means ranging from 30 seconds to 8 minutes. Similarly, time of day was associated with turnaround time, with the longest turnaround times occurring between 0600 and 1500 hours. CONCLUSION: This study demonstrated that patient acuity, destination hospital, and time of day were associated with variation in ambulance turnaround times. Research describing other system characteristics such as current emergency department census and patient handoff procedures may further demonstrate areas for improvement in HTAT. Results from this analysis may be used to inspire EMS administrators and EMS medical directors to start tracking these times to create a predictive model of EMS staffing needs.

The association between prehospital endotracheal intubation attempts and survival to hospital discharge among out-of-hospital cardiac arrest patients.

OBJECTIVES: The benefit of prehospital endotracheal intubation (ETI) among individuals experiencing out-of-hospital cardiac arrest (OOHCA) has not been fully examined. The objective of this study was to determine if prehospital ETI attempts were associated with return of spontaneous circulation (ROSC) and survival to discharge among individuals experiencing OOHCA. METHODS: This retrospective study included individuals who experienced a medical cardiac arrest between July 2006 and December 2008 and had resuscitation efforts initiated by paramedics from Mecklenburg County, North Carolina. Outcome variables were prehospital ROSC and survival to hospital discharge, while the primary independent variable was the number of prehospital ETI attempts. RESULTS: There were 1,142 cardiac arrests included in the analytic data set. Prehospital ROSC occurred in 299 individuals (26.2%). When controlling for initial arrest rhythm and other confounding variables, individuals with no ETI attempted were 2.33 (95% confidence interval [CI] = 1.63 to 3.33) times more likely to have ROSC compared to those with one successful ETI attempt. Of the 299 individuals with prehospital ROSC, 118 (39.5%) were subsequently discharged alive from the hospital. Individuals having no ETI were 5.46 (95% CI = 3.36 to 8.90) times more likely to be discharged from the hospital alive compared to individuals with one successful ETI attempt. CONCLUSIONS: Results from these analyses suggest a negative association between prehospital ETI attempts and survival from OOHCA. In this study, the individuals most likely to have prehospital ROSC and survival to hospital discharge were those who did not have a reported ETI attempt. Further comparative research should assess the potential causes of the demonstrated associations.