Apparatus for improving the distribution of gas in the lungs of a patient receiving respiratory treatment

When treating patients with severely injured or sick lungs, there is often the problem of providing a life sustaining treatment without risking further damage to the lungs as a result of the treatment itself. An apparatus for improving the distribution of gas in the lungs of a patient to alleviate this problem directs a controllable pressure to one or several selected positions on the patient's thorax. In one embodiment of the apparatus, the apparatus includes a vest which includes compartments which can be filled with a fluid under pressure from a pressure source via tubes.