Abstract 352: Development of a Novel Tool for Data Abstraction From 911 Calls for Out-of-hospital Cardiac Arrest

Abstract

Introduction: For out-of-hospital cardiac arrests (OHCAs) unwitnessed by emergency responders, contact with the 911 system provides the earliest point for consistent data collection. Building upon previous tools, we developed a 911 call data abstraction instrument and tested it to see if it reliably tracked key metrics from 911 calls for dispatch assisted CPR in order to guide quality initiatives for OHCA. Methods: Data abstractors applied this tool to a random sample of 23 emergency medical services (EMS)-confirmed, second-party, non-traumatic, non-overdose adult OHCAs occurring prior to first responder arrival from November 2017 to November 2019 in Washtenaw County, Michigan. For each call, data elements were collected by 2 independent reviewers. We focused on key variables: 1) whether the arrest was recognized by dispatch in eligible cases (n=23), 2) whether instructed compressions were provided in eligible cases (n=23), and 3) the 911-time-to-first-instructed-compression (n=11). To evaluate interrater reliability, we calculated kappa statistics for categorical variables and intraclass correlation coefficients (ICC) for continuous variables. Results: We included 23 calls with an average patient age of 64.2 (SD: 10.9) lasting an average of ~5 mins. Overall, 16 patients were men and 7 were women. Thirteen calls originated from private residences, 9 from a public place, and 1 could not be identified. We found that OHCA was recognized by dispatch in 18 of the 23 calls (78%). Reviewers reported instructed compressions occurred in 14 of 23 calls (61%). The median 911-time-to-first-instructed-compression of calls where consistent measurement was possible (n=11) was 197.5 seconds (IQR: 2:30.0-4:44.0). Among calls, kappa statistics for recognition of cardiac arrest and provision of instruction compressions was 1.00 (n=23) and 0.91 (n=23), respectively, while the ICC for time-to-first instructed compression was >0.99 (n=11). Conclusions: Reviewing 911 calls with this tool was capable of collecting reliable information from independent reviewers on key events including critically important times. Collection of these data is a critical first step for evaluating system performance to improve survival from OHCA.