Comparison of the FiO2 delivered by seven models of the self-inflating bag-mask system.

BACKGROUND AND OBJECTIVES Since resuscitators with self-inflating bag-mask systems manufactured and/or commercialized in Brazil are widely available and used in health services, both out- and intra-hospitals, the objective of this study was to determine the O2 fractions delivered by seven resuscitators receiving different O2 flows. METHODS Seven resuscitators with self-inflating bag-mask systems were tested at the Respiratory Unit of the HC/UNICAMP. A wall O2 flowmeter was connected to the resuscitator that received an O2 flow of 1, 5, 10, and 15 L min(-1) and those were connected to a test lung. Resuscitators capable of being connected to an O2 reservoir were tested with and without this accessory Twenty consecutive measurements were performed and the mean determined. RESULTS Only one resuscitator delivered an O2 fraction slightly below the accepted limit (0.80) when used with the O2 reservoir. Without this device, all resuscitators achieved the minimal limit of O2 fraction (0.40). Resuscitators not capable of being connected to an O2 reservoir delivered a higher O2. CONCLUSIONS All resuscitators capable of being connected to an O2 reservoir delivered a higher O2 concentration when connected to this device. Resuscitators that do not have this capability delivered a higher O2 concentration than the ones that could be connected to this device but are used without it.