An apparatus for the resuscitation of cardiac and pulmonary functions.

摘要

1,140,581. Heart and lung resuscitators. C. E. HEWSON. 4 Jan., 1966, No. 365/66. Headings A5R and A5T [Also in Division G3] A lung ventilator comprises a duct 69, 70 and a fitting 14 for introducing lung-ventilating gas to a patient, a fixed volume tank 58 for metering the amount of lung-ventilating gas and connected to the duct, means for introducing a controlled amount of lung-ventilating gas into the tank and valve means 60 in the duct for connecting and disconnecting the tank and the fitting, the said introducing means and said valve means being so arranged that gas is introduced to the tank only when the tank is not connected to the fitting. The lung ventilator is combined with a heart resuscitator comprising a pneumatically operated compressor 12 for exerting pressure on the heart and includes a pneumatic circuit for cyclically operating the lung ventilator and the compressor in timed relation to each other. The control means is disposed in a case 22 which is shaped to form a shoulder lift and which includes a combined handle and head support 38. Straps 16 retain the compressor 12 on the patients chest. The device includes a respiratory mask 14. Oxygen from a supply 18 at 90 p.s.i. flows through an 'on-off' valve 48 and a pressure regulator 52, which reduces the pressure to 48-50 p.s.i. to a pneumatically controlled valve 54 which normally connects the supply to a line 70. A pneumatic pulse generating circuit 56 (see Division G3) is then energised and emits gas pulses at its outlet 78 at 60 per min., and the metering tank 58 is filled under the control of an adjustable regulator 82. A pneumatically controlled valve 60 between the tank and the mask is normally closed. The gas pulses are supplied through a pilot line 68 to a valve 62, which opens in response to each pulse, to direct oxygen in a line 50 through a regulator 82' to the cardiac compressor 12. The gas pulses also operate a counter 64 in a pilot circuit 66 to permit the valve 54 to change over so that oxygen is supplied to a pilot line 72 and disconnected from line 70 only once in every five pulses. When oxygen is supplied to the pilot line 72, the valve 60 is opened to connect the tank 58 with the mask. The valve 60 (see Division F2) includes a spool (118, Figure 5) which, as it moves to open the valve, provides a flow path of increasing dimensions so that the gas volume passing to the mask increases gradually at a predetermined rate. As the tank empties or reaches a preselected minimum pressure, pressure in a pilot line 113 closes a normally open valve 111 to change over the valve 54 to connect the oxygen supply to the line 70 and disconnect the line 72.