STUDIES ON THE OXYGENATION OF DERMIS AND SUBCUTIS IN LIPODERMATOSCLEROSIS

Chronic venous insufficiency (CVI) leads to morphological and function al changes in nutritive capillaries resulting in disturbances of the n utrition of the skin. Up to now, data obtained from transcutaneous mea sured pO2 were taken as an indication for a decreased oxygen supply to the skin. With the aim of obtaining direct information on the tissue oxygenation of dermis and subcutis we have measured the distribution o f tissue pO2 values with needle probes (300 mum tip diameter, Eppendor f-Netheler-Hinz-GmbH, Hamburg). 12 patients with CVI III and 8 healthy volunteers were included in this study. The needle probes were insert ed into the skin of the proximal third of the lower leg and, in patien ts, in the areas with mild and with severe sclerosis (u[cer edge). The pO2 data from the needle probes were compared with pO2 data obtained from transcutaneous surface probes (tcpO2) and with data from laser do ppler flux measurements LDF). In clinically healthy skin the intracuta neously measured pO2 (icpO2) was 51 +/- 7 mmHg (mean +/- S. D.) and th e subcutaneously measured pO2 (scpO2) was 47 +/- 8 mmHg. In lipodermat osclerosis invasively determined pO2-values were lower than in healthy skin, however, no hypoxic or anoxic values were found. Compared with tcpO2-values there was no considerable difference between icpO2-values measured in mild sclerosis and severe sclerosis (icpO2 28 mmHg as com pared to 25 mmHg; scpO2 31 mmHg as compared to 27 mmHg). The icpO2 val ues obtained from the edge of the ulcer showed a large variation from patient to patient (6 mmHg to 42 mmHg). There was no correlation betwe en the pO2 data and the LDF-values.