Abstract: Ventilator apparatus for ventilating the lungs of a patient comprises a source of as pressure to be applied internally or externally to a patient's lungs. The alternating pressure has a complex waveform deconstructable into a large amplitude waveform of a first frequency which may be produced by a blower (18) and a valve (10) and a lower amplitude waveform of a higher frequency which may be produced by a second blower and valve unit (4).

Abstract: A chest covering shell (4) of springy material for fitting over a patient's chest is coupled to an air oscillator. Changes in air pressure in the shell (40) cause ventilation of the patient. A back plate (10) can be used which has vertically extending supports (14) for engagement with the sides (28) of the shell (40) so as to support them and prevent their flexing during use. The edge of the shell (4) has a seal (50 which runs continuously around the periphery of the shell (40). The seal (50) can include an inwardly directed flap (56) in order to provide an effective seal when positive pressures are applied under the shell (40). A backing pad (58) comprising an evacuatable envelope containing solid particles can be used which is able to support the shell (40) and seal against the patient. The pad (58) can be deformed by the weight of the patient and can be evacuated via air outlet (70) to stiffen the envelope by compression of the particle.

Abstract: A chest enclosure apparatus is disclosed for use in producing an assisted ventilation of the lungs of a patient when combined with an air oscillator. The chest enclosure includes a chest covering tunnel member made of a stiff, but flexible material. Additionally, a wall member is included at each end of the tunnel member, with each wall member having a concave radially inner periphery for sealing against the front surface of patient's body and being made of an air-impermeable, flexible cushioning material. A band of a flexible, air-impermeable material is provided and extends from each of the longitudinally running edges of the tunnel member for wrapping in a mutually overlapping around the chest region of a patient's back. A fastener is provided for fastening one of the band in order to hold the bands in the overlapping relationship. Finally, an air passageway is provided for the enclosure in order to allow for a connection to a conventional air oscillator.

Abstract: A patient enclosure for ventilator apparatus comprising a base member (10) and a liftable cover member (12) which in an operative position defines a patient receiving chamber having at least one aperture (13) in the cover member for accommodating a portion of a patients body, the or each such aperture in the cover member being open along an edge of the cover member which overlies the base member in the operative position and containing a seal member for forming a substantially air tight seal in use between the cover member and the patients body and the base member, wherein the seal member takes the form of a flexible curtain (14) having a free edge overlying the base member and means such as straps (19) for tensioning a portion of the curtain to cause the curtain to seal against the base member and the patients body. The enclosure is used in conjunction with a source of oscillating air pressure to form a ventilator.