Ventilation—Cardiac Compression Rates and Ratios in Cardiopulmonary Resuscitation

Abstract

Ventilation-compression frequencies and ratios during cardiopulmonary resuscitation in dogs with ventricular fibrillation and ventilation frequencies in apneic healthy human subjects were studied. Lung inflations interposed between sternal compressions gave better ventilation and about equal carotid blood flows as compared to simultaneous inflations. A ventilation—compression ratio of 3/15 (using air) maintained normal oxygenation and ventilation, whereas 6/30 did not In apneic adults with two inflations (tidal volume 1,000 ml) every 15 seconds, oxygenation and ventilation were adequate with FiO26O compressions per minute, while 120 compressions per minute gave insignificantly greater flows than 72 compressions per minute. The recommendation of a ventilation—compression ratio of 2/15 for one operator and 1/5 interposed for two operators (compressions at one second intervals without interruption) is sound.