Transcutaneous oxygen pressure measured at two different electrode core temperatures in healthy volunteers and patients with arterial occlusive disease.

The influence of two different electrode core temperatures on transcutaneous oxygen pressure (tcPO2) was studied in ten probands and 28 patients with peripheral arterial occlusive disease. Hyperaemisation of skin by an electrode core temperature of 44 degrees C reflects local hyperaemia flow and can be reproduced constantly. At 37 degrees C low tcPO2 values are recorded which are in good accordance with mathematically calculated capillary dome PO2. According to great physiological alterations in skin perfusion tcPO2 (37 degrees C) varies in wide ranges. This mode of measurement is well suited to study physiological autoregulation mechanisms or the influence of drugs on skin perfusion. The herein reported results are: forefoot tcPO2 (37 degrees C, 44 degrees C) in volunteers is significantly higher than in patients; forefoot tcPO2 (37 degrees C, 44 degrees C) of patients with diabetes mellitus is significantly higher than in nondiabetics; prestenotic tcPO2 (37 degrees C, 44 degrees C) is about two times higher than poststenotic tcPO2 (37 degrees C, 44 degrees C); tcPO2 (37 degrees C) in probands decreased significantly during occlusion of the venous circulation; tcPO2 (44 degrees C) increased in probands and patients when standing up; however, tcPO2 (37 degrees C) decreased in healthy persons and increased in patients when standing up; after a 5-min suprasystolic cuff occlusion of the arterial circulation there was a four- to six-fold increase of tcPO2 (37 degrees C) which indicates reactive skin capillary flow. In conclusion tcPO2 (37 degrees C) permits measurement of relative changes of skin capillary flow under physiological conditions so that autoregulating mechanisms can be studied.