Performer fatigue and CPR quality comparing 30:2 to 15:2 compression to ventilation ratios in older bystanders: A randomized crossover trial.
OBJECTIVE
We sought to compare bystander fatigue and CPR quality after 5min of CPR using the 30:2 vs. the 15:2 chest compression:ventilation ratios in a population of older participants.


METHODS
This randomized cross-over study included independent-living participants aged ≥55. Participants completed two 5-min CPR sessions (using 30:2 and 15:2 ratios) on a recording manikin, separated by a 5-min rest. We measured changes in heart rate (HR), mean arterial pressure (MAP), venous lactate (VL; in selected participants), and perceived level of exhaustion (Borg Scale and subjective). CPR quality measures included total number of chest compressions and number of adequate compressions.


RESULTS
The 42 enrolled participants were: mean age 66.0 (range 55-84), female 69.0%, and previously CPR trained 66.7%. Measures of bystander fatigue were similar for each CPR ratio: mean difference in increased HR 1.5 (95%CI -1.5 to 4.5), MAP 1.5 (-1.8 to 4.8), VL 0.2 (-1.1 to 1.4), Borg 0.2 (-0.2 to 0.8), but subjectively reported fatigue level was higher after the 30:2 session. Participants attempted more chest compressions per session using the 30:2 vs. the 15:2 ratio: mean diff. 78.6 (69.5-87.7), but did not complete more adequate compressions: mean diff. 1.9 (-18.9 to 22.9). The decline in number of adequate compressions/min over time was significant but similar in each group.


CONCLUSIONS
In this study of older volunteers, the 30:2 CPR ratio resulted in similar objective measures of fatigue, but higher perceived fatigue than the 15:2 ratio. The 30:2 ratio resulted in proportionally more inadequate compressions.
Department of Emergency Medicine, University of Ottawa, Ottawa, Ontario, Canada. cvaillancourt@ohri.ca
Christian
C
Vaillancourt
Ines
I
Midzic
Monica
M
Taljaard
Brian
B
Chisamore
D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000592:standards*; D018592:Cross-Over Studies; D005221:Fatigue / Q000175:diagnosis*; D005260:Female; D006336:Heart Massage / Q000379:methods; D006801:Humans; D008297:Male; D008348:Manikins; D008875:Middle Aged; D012119:Respiration; D011795:Surveys and Questionnaires