VARIABILITY OF TCPO2-MEASUREMENTS AT 37-DEGREES-C AND 44-DEGREES-C INPATIENTS WITH CLAUDICATION IN CONSIDERATION OF PROVOCATION TESTS

With regard to the increasing use of tcPo2-measurements for the assess ment of peripheral arterial occlusive disease, the variability of the method needs more consideration. We studied the reproducibility of tcP o2 measured at 37-degrees-C and 44-degrees-C, especially under the inf luence of provocation tests, in 21 patients with severe claudication ( ankle artery pressures (AP) 30-100 mmHg) without skin lesions. On 6 da ys within 2 weeks tcPo2 was recorded on the forefoot at 37-degrees-C a nd 44-degrees-C electrode core temperatures a) in supine position, b) in sitting position, c) during O2-breathing, d) during reactive hypere mia (RH). In measurements at 37-degrees-C variation coefficients (VC) were high (mean +/- S.D.: 74 +/- 27%) and could not be improved by oxy gen inhalation nor by the sitting position. Only during RH, VC decreas ed significantly to 49 +/- 23%. At 44-degrees-C VC were still quite hi gh (mean: 42 +/- 24 %) and were inversely correlated with AP. Mean tcP o2 increased under all provocation maneuvres. However, only in the sit ting position VC decreased significantly to 18.7 +/- 8.4% (p < 0.001). Single tcPo2 measurements, both at 37-degrees-C and 44-degrees-C, are of low value in patients with severe claudication. For the evaluation of the individual patient repeated measurements are demanded. Reduced variability may be achieved by measurements at 44-degrees-C in a sitt ing position.