[Effect of positive end expiratory pressure on the intrapulmonary shunt and the oxygen alveolo-arterial difference in adult acute respiratory distress].
The aim of this study was to analyse two groups of 10 patients with hypoxaemia. One group of patients had acute respiratory distress (A.R.D.A.) and the other group was hypoxaemic without acute adult respiratory distress. Both group of patients were ventilated artificially. The authors studied the effect of positive end expiratory pressure (PEEP) of 10 cm H2O on the intra-pulmonary shunt (Qs/Qt) and on the alveolar-arterial oxygen difference [P(A-a)O2]. The values for the shunt and for P(A-a)O2 are calculated at FiO2 of 0.4 and at a FiO2 of 1. The two groups are best distinguished by the difference between the shunt calculated at a FiO2 of 0.4 and at a FiO2 of 1, as the P(A-a)O2 is similar in both groups of patients and is not influenced by the PEEP, either in the A.R.D.A. or in the non-A.R.D.A. group. Without PEEP, A positive value is obtained for Qs-Qt in the A.R.D.A. group and a negative value is obtained in the non A.R.D.A. group. With PEEP of 10 cm, the shunt in patients with A.R.D.A. is greatly reduced and tends towards 0. In the non A.R.D.A. group of patients, the shunt does not vary with the PEEP and the difference remains negative.
D000328:Adult; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood / Q000502:physiology*; D011175:Positive-Pressure Respiration; D011312:Pressure; D011650:Pulmonary Alveoli / Q000503:physiopathology; D012128:Respiratory Distress Syndrome / Q000503:physiopathology* / Q000628:therapy
D010100:Oxygen
Effet de la pression positive en fin d'expiration (P.P.F.E.) sur le shunt intra-pulmonaire et sur la différence alvéolo-artérielle en oxygène [P(A-a)O2] dans la détresse respiratoire aiguë de l'adulte (D.R.A.A.).