Standard CPR Versus Chest Compressions Only

Background: More than two thirds of sudden cardiac arrests are witnessed by bystanders. Bystander cardiopulmonary resuscitation (CPR) doubles survival from cardiac arrest. Importantly, even in witnessed cardiac arrests only 20% of the bystanders commence basic life support. Common reasons for not commencing include panicking and the perceived inability to perform CPR correctly. A meta-analysis could demonstrate that a simplification of the algorithm (compression-only dispatcher-assisted bystander CPR) led to a 22% increase in survival-to-hospital discharge. A recently published trial of the research group could demonstrate that the presence of a flowchart has a positive effect on the quality of BLS while at the same time increasing the rescuers' confidence. Nonetheless, performing CPR is exhausting. Previous publications have emphasized increasing fatigue with the duration of CPR efforts in both, standard and chest compressions-only CPR. Consequently, the investigators wanted to test the hypothesis that chest compressions (CC) are delivered more correctly regarding the depth when utilizing the standard Basic Life Support (BLS) algorithm with the aid of a flowchart as compared to the CC only algorithm utilizing an adapted CPR flowchart in a manikin resuscitation model. Methods: After consent of the Research Ethics Board of Medical University of Vienna and obtaining written informed consent of the participants, 84 medically untrained laypersons will be randomised to perform flow-chart assisted CPR for 300s following standard CPR guidelines or CC only CPR. The primary outcome parameter will be the total number of CC achieving the correct depth of 50-60mm. Secondary outcome parameters will be hands-off time, the total number of CC, and the compression rate. The total number of delivered rescue breaths, tidal volume, and time to deliver these will also be evaluated. Furthermore, the subjective point of exhaustion affecting the CPR quality, the reason for discontinuati