EFFECTS OF INSPIRATORY PRESSURE SUPPORT ON OXYGENATION AND CENTRAL HEMODYNAMICS IN THE NORMAL HEART DURING THE POSTOPERATIVE PERIOD

Ten patients without cardiac disease or pulmonary dysfunction were exp osed to an inspiratory pressure of 0, 10 and 20 cmH(2)O, in random ord er, via a nasal mask during the first postoperative day after scolioti c surgery. These patients were in the supine position, and a BiPAP res piratory assist device was used. Arterial oxygen saturation increased significantly during the application of 10 and 20 cmH(2)O, while none of the haemodynamic parameters (cardiac output, central venous pressur e, right ventricular ejection fraction, right ventricular end diastoli c volume, mean pulmonary artery pressure, pulmonary artery wedge press ure, pulmonary vascular resistance) changed significantly, contrary to the findings during continuous positive airways pressure treatment. I n addition, the BiPAP was generally well tolerated by the patients.