Comparison of four methods of preoxygenation

Abstract

Summary: We studied four different techniques of preoxygenation in 20 healthy volunteers, by continuous analysis of respired gases. Three minutes of tidal breathing from a Magill breathing system or four vital capacity breaths from a nonrebreathing system were found to be equally effective, whereas four vital capacity breaths from a Magill breathing system were less effective. Maximal expiration before application of the face mask resulted in improved oxygenation when four vital capacity breaths were taken from a Magill system. © 1990 Copyright: 1990 British Journal of Anaesthesia.