Do laypersons need App-linked real-time feedback devices for effective resuscitation? - Results of a prospective, randomised simulation trial

Background: App-linked real-time feedback-devices for cardiopulmonary resuscitation (CPR) aim to improve laypersons' resuscitation quality. Resuscitation guidelines recommend these technologies in training settings. This is the first study comparing resuscitation quality of all App-linked feedback-devices currently on market. Methods: A prospective randomised simulation study was performed. After standardised instructions, participants performed 2-minutes compression-only CPR on a manikin without feedback (baseline). Afterwards, participants performed 4 x 2 min CPR with four different feedback devices in randomised order (CorPatch (R) Trainer, CPRBAND AIO Training, SimCPR (R) ProTrainer, Relay Response (TM)) (intervention). CPR metrics (chest compression depth (CD), chest compression rate (CR), percentage of correct CD/CR (%), correct hand position, correct chest recoil, and technical preparation-time) were assessed. Devices data were compared to the baseline group using Wilcoxon testing with IBM SPSS (primary outcome). Differences between devices were analysed with ANOVA testing (secondary outcome). Normally distributed data were described as mean +/- standard deviation (SD) and non-normally distributed data as Median [Interquartile range (IQR). CPR self-confidence was measured by means of questionnaire before and after feedback devices' use. Comparison was performed by students t-test. Results: Forty participants were involved. SimCPR (R) ProTrainer was the only device, which resulted in guideline-compliant chest compressions (Mean +/- SD:5.37 +/- 0.76) with improved chest compression depth (p < 0.001), and percentage of correct chest compression depth (p < 0.001) compared to unassisted CPR (baseline). CorPatch (R) Trainer as the only device with audio-visual recoil instructions resulted in improved chest recoil (Mean +/- SD:72.25 +/- 24.89) compared to baseline (Mean +/- SD:49.00 +/- 42.20; p < 0.01), while the other three devices resulted in significantly lower chest recoil rates (CPRBAND AIO Training: 37.03 +/- 39.90; p < 0.01, SimCPR (R) ProTrainer: Mean +/- SD:39.88 +/- 36.50; p = 0.03, Relay Response (TM): Mean +/- SD:36.88 +/- 37.73; p = 0.02). CPR quality when using the different feedback devices differ in chest compression depth (p = 0.02), chest compression rate (p < 0.001), percentage of correct chest compression depth/rate (p = 0.03/p = 0.04), and technical preparation-time (p < 0.001). Feedback-devices' use increased participant's CPR self-confidence (p < 0.001). Conclusion: Although, CPR feedback devices show improved CPR performance in layperson in some metrics, none of the tested CPR feedback devices supported layperson in overall adequate CPR performance. More and better technical functionality is necessary, to fully utilise the potential of CPR feedback devices and to prevent a worsening of CPR performance when layperson use this technology.