[Disordered cutaneous microcirculation in diabetic neuropathic foot ulcer. Is modification by retrograde transvenous...

Due to the high risk of amputation they involve, diabetic neuropathic plantar ulcers (DNPU) must be regarded as a late manifestation/complication of diabetes mellitus. The suspected cause of these ulcers--disturbed cutaneous microcirculation--was studied by simultaneously measuring laser-Doppler flux (LDF) and cutaneous oxygen tension (pCUO2) in 14 patients with DNPU at three differently affected sites (dorsal forefoot, ulcer edge, lower leg). Dynamic tests (arterial occlusion, local hyperthermia) as a measure of vascular reactivity showed significantly reduced pCUO2 parameters coinciding with elevated LDF values. This reflects a shift of blood flow from the nutritive capillaries towards deeper vessels. Abolition of normal vasoconstriction in the arteriovenous shunt vessels by diabetic polyneuropathy is the assumed cause of increased AV perfusion, with a consequent rise in LDF values. In a subgroup of the above patients (n = 7) undergoing daily intravenous retrograde perfusion therapy (RVP) over 10 days several basic and dynamic microcirculatory functions were studied before and after this treatment. This subgroup showed on the forefoot and the lower leg a remarkable improvement of the microcirculatory parameters investigated, suggesting a better oxygen supply to the tissues after RVP therapy.