Could CPAP Devices Be Used to Ventilate Cardiac Arrest Patients? A Bench Study

Objectives: To investigate the potential efficacy of a commercial continuous positive airway pressure (CPAP) ventilator to provide effective respiratory support in a simulated scenario of out-of-hospital cardiac arrest (OHCA). Methods: The study was conducted on a high-fidelity manikin (SimMan 3 G (TM), Laerdal, NOR) connected to the ASL 5000 (TM) Lung Simulator (IngMar Medical, USA). To simulate OHCA, we set no spontaneous respiratory acts and physiological respiratory system resistance (13 cmH(2)O/L.sec) and compliance (50 mL/cmH(2)O). The Respironics BiPAP A40 ventilatorI (Philips, NL) was used to provide ventilatory support while operating in CPAP mode. Tests were performed at different values of positive pressure of the CPAP ventilator (P-CPAP: 5, 7.5, 10, 12.5 and 15 cmH(2)O) and the intrapulmonary volume (tidal volume, Vt) measured via the simulator software computer interface. A trained physician performed the tests. Our primary outcome was a V-T of approximate to 500-600 mL with an intermittent maneuver simulating cardiopulmonary resuscitation (CPR)-like ventilatory support practice according to international guideline-based target (1-sec ventilation followed by 1-sec pause). Results: In intermittent ventilatory support tests, PCPAP levels of 12.5, and 15 cmH(2)O resulted in a V-T equal to 508 +/- 13 mL, and 557 +/- 44 mL respectively (p = 0.04), thus approaching the V-T target. Conclusions: We provide preliminary evidence of the potential efficacy of CPAP ventilators designed for home use to provide effective respiratory support to a simulated respiratory arrest patient.