Chest compression quality, exercise intensity, and energy expenditure during cardiopulmonary resuscitation using compression-to-ventilation ratios of 15:1 or 30:2 or chest compression only: a randomized, crossover manikin study

ABSTRACT

OBJECTIVE: Our aim was to compare the compression quality, exercise intensity, and energy expenditure in 5-minute single-rescuer cardiopulmonary resuscitation (CPR) using 151 or 302 compression-to-ventilation (CV) ratios or chest compression only (CCO). METHODS: This was a randomized, crossover manikin study. Medical students were randomized to perform either type of CPR and do the others with intervals of at least 1 day. We measured compression quality, ratings of perceived exertion (RPE) score, heart rate, maximal oxygen uptake, and energy expenditure during CPR. RESULTS: Forty-seven students were recruited. Mean compression rates did not differ between the 3 groups. However, the mean percentage of adequate compressions in the CCO group was significantly lower than that of the 151 or 302 group (31.2±30.3% vs. 55.1±37.5% vs. 54.0±36.9%, respectively; P<0.001) and the difference occurred within the first minute. The RPE score in each minute and heart rate change in the CCO group was significantly higher than those of the CV ratio groups. There was no significant difference in maximal oxygen uptake between the 3 groups. Energy expenditure in the CCO group was relatively lower than that of the 2 CV ratio groups. CONCLUSION: CPR using a 151 CV ratio may provide a compression quality and exercise intensity comparable to those obtained using a 302 CV ratio. An earlier decrease in compression quality and increase in RPE and heart rate could be produced by CCO CPR compared with 151 or 302 CV ratios with relatively lower oxygen uptake and energy expenditure.