[Validity of the transcutaneous PO2-measurement during pharmacologically induced changes of skin perfusion (author's transl)].

The validity of transcutaneous oxygen partial pressure (tcPO2) was tested during pharmacological vasodilatation and vasoconstriction of the skin. Measurements of transcutaneous oxygen partial pressure (tcPO2) were done on the hairless skin of the abdomen in 18 anaesthetized rabbits, when beta-pyridyl-carbonyl (Ronicol) was used as a vasodilator and vasopressin (Pitressin) as a vasoconstrictor. Vasodilation yielded no significant influence on the tcPO2-measurement. Vasoconstriction, however, resulted in a marked decrease of the tcPO2-signal (p less than 0.001). During this phase tcPO2 did no longer reflect arterial PO2 which remained nearly constant. In this experimental model vasoconstrictive drugs may cause a marked underestimation of the arterial oxygen tension. The dependence of the tcPO2-measurement on maximal local skin perfusion should be considered in intensive care patients.