INFLUENCE OF DIABETIC NEUROPATHY ON SKIN MICROCIRCULATION ASSESSED BYTRANSCUTANEOUS OXYMETRY

Skin microcirculation was investigated in 45 patients with long term d iabetes and with severe, moderate or no neuropathy, and in 15 controls . Transcutaneous oxygen pressure (tcPo(2)) measurements on the forefoo t were performed at 37 degrees C to assess local capillary flow al rea l, during leg dependency and reactive hyperaemia, and also at 44 degre es C, including the response to oxygen inhalation. TcPo2 (37 degrees C ) at rest was significantly elevated with an increasing degree of neur opathy (Controls: 4.8 +/- 3.7; patients without neuropathy: 4.2 +/- 2. 9; with moderate neuropathy: 6.0 +/- 2.9 (p < 0.01); with severe neuro pathy: 7.2 +/- 4.2 mmHg (p < 0.001)). Leg dependency resulted in a dec rease of tcPo(2) in the controls, while an increase was observed in 18 .6% of the measurements in patients, reflecting a disturbed vasoconstr ictor response. Regardless of neuropathy, absolute tcPo(2) values duri ng reactive hyperaemia were reduced in all patient groups as well as t cPo(2) (44 degrees C) and its increase during oxygen breathing. Diabet ic neuropathy is likely to increase local capillary flow, while the ot her differences to healthy controls may be contributed to a microcircu lation disorder independent of neuropathy.