Abstract 17353: Comparison of Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD) when Processing Cardiac Arrest Calls
Background: Prompt emergency medical service (EMS) system activation with rapid delivery of pre-hospital treatment is essential for patients suffering out-of-hospital cardiac arrest (OHCA). The two most commonly used dispatch tools are medical priority dispatch (MPD) and criteria based dispatch (CBD). We compared cardiac arrest call processing using these two dispatch tools in two different dispatch centres.
Methods: Observational study of adult EMS confirmed (non-EMS witnessed) OHCA calls during one year in Richmond US (MPD) and Oslo (CBD). Patients receiving CPR prior to call, interrupted calls or calls where the caller did not have access to the patients were excluded from analysis. Dispatch logs, ambulance records and digitalized dispatcher and caller voice recordings were analyzed and compared using a non-parametric Mann-Whitney U-test for continuous data and Fisher’s Exact test for categorical data.
Results: The MPD-site processed 182 cardiac arrest calls and the CBD-site 232, of which 100 and 140 calls met the inclusion criteria, respectively. The recognition of cardiac arrest was not different in the MPD and CBD systems; 82% vs. 77% (p=0.42), and pre-EMS arrival CPR instructions were offered to 81% vs. 74% (p=0.22) of callers, respectively. Time to ambulance dispatch was median (95% confidence interval) 15 (13, 17) vs. 33 (29, 36) seconds (p<0.001) and time to chest compression delivery; 4.3 (3.7, 4.9) vs. 3.7 (3.0, 4.1) minutes for the MPDS and CBD systems, respectively (p=0.05).
Conclusion: Ambulance dispatch was swift in both systems but significantly faster in MPD. Although pre-arrival CPR instructions were frequently offered, chest compressions were delayed in both systems. Rapid recognition of cardiac arrest and improved instructions is needed to facilitate earlier lay rescuer CPR.
- © 2013 by American Heart Association, Inc.