Dispatchers impression plus Medical Priority Dispatch System reduced dispatch centre times in cases of out of hospital cardiac arrest. Pre-alert--a prospective, cluster randomized trial

Abstract

Aim of the study: Dispatch centre processing times for out-of-hospital cardiac arrest or critically ill patients should be as short as possible. A modified 'pre-alert' dispatch workflow might be able to improve the processing time.

Methods: Between October 2010 and May 2011 dispatch events, suspicious for cardiac arrest, were prospectively randomized in 24h clusters. The emergency medical service of the intervention group got, based on the dispatchers impression, a 'pre-alert' alarm-message followed by the standard Medical Priority Dispatch System query whereas the control group did not.

Results: In 225 clusters 1500 events were eligible for analysis. Data are presented as median and 25-75 interquartile ranges. Per-protocol analysis demonstrated for the intervention group on 'pre-alert' days a median processing time of 143 s (109-187; n=256) versus 198 s (167-255; n=502) in the control group on non 'pre-alert' days, with a difference of 0.23 log-seconds (p<0.001; 95% CI 0.74-0.28). In critical ill patients, intention-to-treat analysis showed for the intervention group a median of 168 s (131-264; n=153) versus 239 s (176-309; n=164) in the control group, with a difference of 1.4 log-seconds (p<0.001; 95% CI 1.25-1.55).

Conclusion: Dispatch times can effectively be reduced in cases of out-of-hospital cardiac arrest or critical ill patients with a 'pre-alert' dispatch workflow in combination with the Medical Priority Dispatch System protocol. This might play an important role in improving patient care.