Evaluation of the transcutaneous oxygen method used at 37°C for measurement of reactive hyperaemia in the skin

Abstract

The transcutaneous oxygen electrode used at an electrode temperature of 35.degree.-37.degree. C measures changes in PO2 [partial pressure O2] at the skin surface that are mainly determined by changes in skin blood flow. Simultaneously, information about tissue PO2 in a defined skin area can be obtained by calculation. The reproducibility of this new application of the transcutaneous PO2 technique and factors influencing the recordings were analyzed. Reactive hyperemia was best recorded at 37.degree. C, where the coefficient of variation (CV) was 14% and the correlation coefficient was 0.90 between duplicate measurements within 15 min (n = 57). The day-to-day variation was greater (CV 19-28%). No significant spatial differences in reactive hyperemia were noted when the distance between the electrodes was no > 3 cm on the same forearm. A slightly lower reactive hyperemia was noted when the arm with the electrode was elevated above the level of the heart, as compared with a lower position. Age and sex had significant influence, children (n = 34) exhibiting a greater postocclusive peak tcPO2 [transcutaneous PO2] response than aults (n = 67). In adults, females (n = 30) showed significantly higher peak tcPO2 values during reactive hyperemia than males. This method is a new application of the tcPO2 technique and can be used as a noninvasive tool for simultaneous blood flow and tissue PO2 studies in microcirculatory research.