Single Ventilation during Cardiopulmonary Resuscitation Results in Better Neurological Outcomes in a Porcine Model of Cardiac Arrest

Abstract

Purpose

Recent basic life support (BLS) guidelines recommend a 30:2 compression-to-ventilation ratio (CV2) or chest compression-only cardiopulmonary resuscitation (CC); however, there are inevitable risks of interruption of high-quality cardiopulmonary resuscitation (CPR) in CV2 and hypoxemia in CC. In this study, we compared the short-term outcomes among CC, CV2, and 30:1 CV ratio (CV1).

Materials and Methods

In total, 42 pigs were randomly assigned to CC, CV1, or CV2 groups. After induction of ventricular fibrillation (VF), we observed pigs for 2 minutes without any intervention. Thereafter, BLS was started according to the assigned method and performed for 8 minutes. Defibrillation was performed after BLS and repeated every 2 minutes, followed by rhythm analysis. Advanced cardiac life support, including continuous chest compression with ventilation every 6 seconds and intravenous injection of 1 mg epinephrine every 4 minutes, was performed until the return of spontaneous circulation (ROSC) or 22 minutes after VF induction. Hemodynamic parameters and arterial blood gas profiles were compared among groups. ROSC, 24-hour survival, and neurologic outcomes were evaluated at 24 hours.

Results

The hemodynamic parameters during CPR did not differ among the study groups. Partial pressure of oxygen in arterial blood and arterial oxygen saturation were lowest in the CC group, compared to those in the other groups, during the BLS period ( p=0.002 and p<0.001, respectively). The CV1 groups showed a significantly higher rate of favorable neurologic outcome (swine CPC 1 or 2) than the other groups ( p=0.044).

Conclusion

CPR with CV1 could promote better neurologic outcome than CV2 and CC.