[The pH, PCO2 and PO2 of pleural fluid. Variations and diagnostic value]

The pH, the PCO2 and the PO2 of pleural liquid in 100 patients in the pneumology unit of the Sfax Hospital been measured. Variations according to etiology have been noticed: 44 tubercular pleurisies have presented an acid pH, a high PCO2 and a low PO2, without variation according of the evolution; 34 cancerous pleurisies were divided as follow: recent pleurisies with alcaline pH, normal PO2 and PCO2; neoplastic pleurisies with developed degree with acid pH, low PO2 and high PCO2; 6 cases of cardiac pleurisies have presented a very high PO2; some other etiologies have been explored (bacterial, viral, cirrhotic, rheumatoid, pancreatic). Afterwards, we have tried to bring out some physio-pathological explanations. At the end of this study, the gazometry of pleural liquid, of easy execution and rapid result, seems to be a useful complementary biological test.