Abstract 481: Cardiopulmonary Resuscitation: The Effect of Fatigue on Professional Rescuers During Continuous Chest Compressions

Abstract

Introduction: It is reported that quality of chest compressions (CC) during cardiopulmonary resuscitation (CPR) for both professional and non-professional rescuers often do not meet guideline requirements. Devices which provide feedback on the quality of CCs are designed to reduce the incidence of suboptimal compressions and promote the administration of effective CCs. Objective: This analysis investigates the effect of CPR duration on the performance of continuous CCs delivered by professional rescuers. Methods: Data were collected from a first responder group based in Texas, USA. Responders were instructed to use a CPR depth feedback device (Laerdal CPRmeter) and an automatic external defibrillator (AED; HeartSine SAM 350P) when attending sudden cardiac arrest events. The AED was configured with a shock protocol separated by 2-minute episodes of CPR and rescuer CC depth and rate were guided by the CPR depth feedback device. CC depth and rate data were processed for 174 patient events. Each CPR episode was divided into 4-analysis windows, 30-seconds in duration. Mean CC depth and rate data was calculated for each window. There were 1433 observations of CC depth and rate available for analysis across 414 CPR episodes. The data was fitted by a multiple linear regression model to assess the effect of CPR duration on CC performance. Results: The mean CC depth at the beginning of an event was 49.01 +/-0.51 mm. CC depth decreased by 0.82 mm, for each passing 30-second interval (p < 0.001). The mean CC rate at the beginning of an event was 111.17 +/- 0.33 compression per minute (CPM). No significant difference was observed between CC rate and duration of continuous CCs (p = 0.896) however there was a significant increase in CC rate observed of 0.408 CPM for each elapsed 2-minute CPR episode (p = 0.011). Conclusion: A reduction in CC depth was observed within each CPR episode, which may be indicative of fatigue during continuous CCs. Although a reduction of 3.28 mm throughout a 2-minute period of CPR may be clinically insignificant, this effect was observed within a trained rescuer group with CPR feedback. Further research is required to assess the effect of fatigue in non-professional responders.