The volumes delivered to a resuscitation manikin were compared using four ventilatory techniques: mouth-to-mouth, mouth-to-mask, one-person bag-valve-mask, and two-person bag-valve-mask. The effects of experience and sex of the rescuer on the resuscitation volume delivered were also evaluated. The volume delivered using the one-person bag-valve-mask technique was significantly less than that using the other three techniques (P < 0.001). The experience and sex of the rescuer made no significant difference in the volume delivered using any of the techniques. As compared with the one-person technique, bag-valve-mask ventilatory volume improved significantly when it was performed as a two-person technique. The mean volumes delivered using mouth-to-mouth and mouth-to-mask ventilation were lower than those recommended by the American Heart Association. Emphasis must be placed on ventilation with an adequate volume when these techniques are taught. When mouth-to-mouth and mouth-to-mask ventilation are taught, a spirometer should be used with the manikin so that the rescuer can learn how to estimate an adequate expired volume.
Hess et al. (Mon,) studied this question.