[The importance of continuous intra-arterial PO2 measurement for evaluation of PO2 changes with drugs, positioning and hyperoxygenation (author's transl)].

In 26 adult patients arterial pO2 was measured continuously with intra-arterial pO2 electrodes over 24 hr after cardiac surgery. The effects of nitroglycerin, Thalamonal and change of body position were investigated. Hyperoxygenation with 100% O2 was tested. The following results were obtained: 1. pO2 and drugs: i.v. nitroglycerin and Thalamonal lead to a decrease in pO2, which occurred with a delay after the blood pressure fall. - 2 pO2 and body position: In the majority of patients with mitral stenosis and in one patient with acute myocardial infarction we found increased pO2 values with 40 degrees head up tilt as compared to supine position. - 3. Hyperoxygenation: The peak values of pO2 after a F1O2 of 1.0 were reached between 6-18 min, with a gradual fall afterwards. The relationship of measured pO2 values, cardiac disease and surgical procedures is discussed.