A simple method to increase the FDO2 of resuscitator bags

Four resuscitator bags were studied to see if the delivered fractional oxygen percentage (FDO2) could be affected by manually controlling the inherent reexpansion rate of the bag so as to allow a greater entrainment of oxygen rather than air into the bag. Flow rates of oxygen into the bag were varied: 5, 10, 15, and 20 liter/min. For each flow rate, bag refill (reexpansion) times were varied: 1, 2, 4 sec. The results show that such a maneuver will effectively increase the FDO2 of the bags at all flow rates tested--in certain instances to values greater than 0.8. This maneuver would be important to resuscitation situations where it is desirable to achieve better patient oxygenation.