Different Resting Methods in Improving Laypersons Hands-Only Cardiopulmonary Resuscitation Quality and Reducing Fatigue: A Randomized Crossover Study

Abstract

Objective: To determine the effects of different resting methods with various rest-start points or rest-compression ratios on improving cardiopulmonary resuscitation (CPR) quality and reducing fatigue during continuous chest compressions (CCC) in 10-min hands-only CPR scenario.

Methods: This prospective crossover study was conducted in 30 laypersons aged 18-65. Trained participants were randomized to follow different orders to perform following hands-only CPR methods: (1) CCC, 10-min CCC; (2) 4+6, 4-min CCC + 6-min of 10-s pause after 60-s compressions; (3) 2+8 (10/60), 2-min CCC + 8-min of 10-s pause after 60-s compressions; (4) 5/30, 2-min CCC + 8-min of 5-s pause after 30-s compressions; (5) 3/15, 2-min CCC + 8-min of 3-s pause after 15-s compressions. CPR quality (depth, rate, hands-off duration, chest compression fraction (CCF)) and participants' fatigue indicators (heart rate, blood pressure, rating of perceived exertion (RPE)) were compared among methods of different rest-start points and different rest-compression ratios with CCC.

Results: Twenty-eight participants completed all methods. All resting methods reduced the trend of declining compression depth and the trend of increasing RPE while maintaining CCF of more than 86%. In methods with different rest-start points, the 2+8 method showed no difference in overall CPR quality or fatigue, but better CPR quality of every minute than 4+6 method. In methods with different rest-compression ratios, the 3/15 method showed the best CPR quality and the highest heart rate increment.

Conclusion: During prolonged hands-only CPR, appropriate transient rests were associated with higher CPR quality and lower subjectively perceived fatigue in laypersons.

Keywords: Hands-only CPR; High-quality CPR; Laypeople; Rescuer fatigue; Rest.

Fig. 1

Flow diagram of the study. CCC, 10-min CCC; 4+6, 4-min CCC + 6-min of 10-s pause after 60-s compressions; 2+8 (10/60), 2-min CCC + 8-min of 10-s pause after 60-s compressions; 5/30, 2-min CCC + 8-min of 5-s pause after 30-s compressions; 3/15, 2-min CCC + 8-min of 3-s pause after 15-s compressions; CPR, cardiopulmonary resuscitation.

Fig. 2

Comparison of chest compression depth, percentage of adequate compression depth, and leaning depth over 10 minutes in different methods. (n = 28) Values are shown as median and interquartile range. CCC, 10-min CCC; 4+6, 4-min CCC + 6-min of 10-s pause after 60-s compressions; 2+8 (10/60), 2-min CCC + 8-min of 10-s pause after 60-s compressions; 5/30, 2-min CCC + 8-min of 5-s pause after 30-s compressions; 3/15, 2-min CCC + 8-min of 3-s pause after 15-s compressions. ǂ Significant difference between different method (P<0.05, Friedman test); * Significant difference between the marked minute with its previous minute (P<0.05, Wilcoxon signed ranks test).

Fig. 3

Comparison of rating of perceived exertion (RPE) over 10 minutes in different methods. (n = 28) Violin plot showing the medians, interquartile range, and min-max values. CCC, 10-min CCC; 4+6, 4-min CCC + 6-min of 10-s pause after 60-s compressions; 2+8 (10/60), 2-min CCC + 8-min of 10-s pause after 60-s compressions; 5/30, 2-min CCC + 8-min of 5-s pause after 30-s compressions; 3/15, 2-min CCC + 8-min of 3-s pause after 15-s compressions. ǂ Significant difference between different method (P<0.05, Friedman test); * Significant difference between the marked minute with its previous minute (P<0.05, Wilcoxon signed ranks test).