Manual respirator apparatus for use with automatic respirators

A manual respirator apparatus for connection to an inhalation line connected between an automatic respirator and a patient and usable with a breathing gas supply under pressure, comprises, a block housing having a breathing gas supply inlet connected to the breathing gas supply, an inhalation line connectable to the inhalation line and an inhalation line outlet connectable to the patient and an exhalation inlet connected from the patient to the block housing. The block housing has a pressure chamber therein and is connected to an elastic breathing gas bag. A connection housing in the passage between the inlet from the gas supply line to the pressure chamber has adjusting valve means in the pressure chamber responsive to the pressure therein and to the fluctuation of the elastic breathing gas bag to permit flow of respirator gas through the connecting passage. A delivery passage is defined between the pressure chamber and the inhalation line and it contains one or more outlet valves which are openable at predetermined pressures to pass the respective gas from the pressure chamber into the inhalation line. The exhalation line is connected into the block housing at the location of a diaphragm chamber which has a diaphragm closing the exhalation gas inlet during the inhalation cycle. The diaphragm is pressured by a gas supplied from the pressure chamber and when this pressure chamber pressure goes down, the exhalation line opens to accept gas into the block housing. The exhalation gas is then passed outwardly, for example, for use in measurement devices and perhaps circulated back to the block housing for delivery through an anaesthesia gas scavenging bag and then eventual discharge to atmosphere.