Background: Physical and mental workload during cardiopulmonary resuscitation (CPR) is challenging under extreme working conditions. We hypothesized that the mechanical chest-compression device Lund University Cardiac Assist System (LUCAS) increases the effectiveness of CPR, decreases the physical workload and improves the mental performance of the emergency medical service (EMS) staff during simulated emergency helicopter flights.
Methods: During simulated helicopter flights, 12 EMS teams performed manual or LUCAS-CPR on a manikin at random order. Compression depth, rate, overall time of compressions, application of drugs and defibrillation were recorded to test the quality of CPR. Heart rate monitoring of EMS members was used as a surrogate of physical workload. Cognitive performance was evaluated shortly after each flight by a questionnaire and a memory test about medical and extraneous items presented to the teams during the flights.
Results: Overall times of chest-compressions were similar, compression rate (101.7±9.6/min) was lower and compressions were deeper (3.9±0.2cm) with LUCAS as compared to manual CPR (113.3±19.3/min and 3.7±0.4cm) (P<0.01, respectively). Heart rates of the EMS staff were increased after manual as compared to mechanical CPR (100.1±21.0 vs. 80.4±11.3, P<0.01). Results of the questionnaire (93.6±6.9% vs. 87.0±7.3% correct answers, P<0.01) and memory test (22.4±15.4% vs. 11.3±7.5%, P<0.02) were significantly better after LUCAS resuscitation. Dosing of drugs, application intervals and rate of correct handling of drugs and defibrillation were not different between LUCAS or manual CPR.
Conclusions: During simulated helicopter flights LUCAS-CPR improved the efficacy of chest-compressions, was physically less demanding and provided enhanced cognitive performance of the EMS team as compared to manual CPR.