Advantage of CPR-first over call-first actions for out-of-hospital cardiac arrests in nonelderly patients and of noncardiac aetiology.

AIM To assess the benefit of immediate call or cardiopulmonary resuscitation (CPR) for survival from out-of-hospital cardiac arrests (OHCAs). METHODS Of 952,288 OHCAs in 2005-2012, 41,734 were bystander-witnessed cases without prehospital involvement of physicians but with bystander CPR (BCPR) on bystander's own initiative. From those OHCAs, we finally extracted the following three call/BCPR groups: immediate Call+CPR (N=10,195, emergency call/BCPR initiated at 0 or 1 min after witness, absolute call-BCPR time interval=0 or 1 min), immediate Call-First (N=1820, emergency call placed at 0 or 1 min after witness, call-to-BCPR interval=2-4 min), immediate CPR-First (N=5446, BCPR initiated at 0 or 1 min after witness, BCPR-to-call interval=2-4 min). One-month neurologically favourable survivals were compared among the groups. Critical comparisons between Call-First and CPR-First groups were made considering arrest aetiology, age, and bystander-patient relationship after confirming the interactions among variables. RESULTS The overall survival rates in immediate Call+CPR, Call-First, and CPR-First groups were 11.5, 12.4, and 11.5%, respectively without significant differences (p=0.543). Subgroup analyses by multivariate logistic regression following univariate analysis disclosed that CPR-first group is more likely to survive in subgroups of noncardiac aetiology (adjusted odds ratio; 95% confidence interval, 2.01; 1.39-2.98) and of nonelderly OHCAs (1.38; 1.09-1.76). CONCLUSIONS Immediate CPR-first action followed by an emergency call without a large delay may be recommended when a bystander with sufficient skills to perform CPR witnesses OHCAs in nonelderly people and of noncardiac aetiology.