ll provide inspired oxygen concentrations of 90%. Certain ideal criteria have been laid down for bag-valve-mask devices used in resuscitation The requirements recommended include:The bag material should be transparent and convey a satisfactory "feel". It should not absorb anesthetic or noxious gases and should possess sufficient recoil to draw in gases from a reservoir or a draw over anesthesia circuit. Both inlet and outlet valves should be of robust construction, competent to prevent rebreathing or leaks, incapable of malfunction or jamming with a fresh gas flow (of oxygen) up to 15L/min. The valves should be easy to take apart, clean and reassemble (except in disposable models); incorrect reassembly should be impossible. The inlet valve should be capable of being fitted with a filter (to exclude noxious gases) and an oxygen reservoir bag. The patient valve should have standard ISO 15/22 mm fittings. The patient valve should incorporate, or be capable of being fitted with, a PEEP valve. The bag should be capable of delivering a tidal volume of up to 1500 ml in the adult version and ventilation rates of up to 45/min in the pediatric version. Infant, pediatric and adult versions of the device should be available. The device should function adequately during all common environmental conditions and temperature extremes. When used by one person, a considerable degree of skill is required to maintain a patent airway and gas-tight seal with one hand, while squeezing the bag with the other. This is only likely to be achieved by someone who regularly uses a bag-valve-mask device. Too much air leak will result in hypoventilation, while excessive tidal volumes may result in gastric insufflation and increased risk of regurgitation. If ventilation has to continue with a bag-valve-mask, the two-person technique is preferable; one person holds the facemask in place using both hands and an assistant squeezes the bag. In this way ...
