DISTURBANCES OF CUTANEOUS MICROCIRCULATION IN PATIENTS WITH DIABETIC LEGS - ADDITIONAL PARAMETERS FOR A NEW THERAPEUTIC CONCEPT

To study disturbed microcirculation involved in the pathogenesis of di abetic neuropathic plantar ulcers (DNPU), we recorded dynamic changes in laser-Doppler flux (LDF) and cutaneous oxygen tension (p(cu)O(2)) c aused by short-time arterial occlusion and local heating at three diff erent sites (forefoot, ulcer edge, lower leg) in patients (n = 14) wit h DNPU and healthy controls (n = 18). Significantly reduced dynamic p( cu)O(2) parameters coincided with a significant increase of flux in th e patient group. This post-stimulatory ''hypoxic hyperemia'' indicates a shifting of blood flux, reducing circulation of the nutritive capil laries comparable to an internal ''steal effect''. This may predispose to the development of DNPU when additional stresses influence the ini tial borderline balance, characterized by similar p(cu)O(2) and increa sed flux values compared to controls. Abolishment of normal vasoconstr iction in the shunt vessels by diabetic polyneuropathy is the assumed cause of increased arteriovenous perfusion and therefore raised flux v alues. Non-invasive testing of microcirculatory functions demonstrates characteristic disturbances in DNPU patients and could be used as add itional parameters for new therapeutic concepts as the intravenous ret rograde perfusion (RVP). After RVP therapy, applied to a subgroup (n = 7) of the patients, some dynamic microcirculatory parameters improved , allowing a preliminary quantitative evaluation of a therapeutic regi men.