Early Detection of Microcirculatory Impairment in Diabetic Patients With

OBJECTIVE — To assess microcirculatory impairment and alterations of the skin oxygen supply in diabetic patients with foot at risk. RESEARCH DESIGN AND METHODS — This study evaluated skin blood flow in 21 type 2 diabetic patients with a foot at risk (defined as a foot with neuropathy but without ulceration or previous ulcerations), 20 type 2 diabetic patients without foot lesions or neuro-pathy, and 21 normal subjects as a control group. The skin blood flow was determined by measuring the transcutaneous oxygen pressure (TcPO2) at the dorsum of the foot in supine and sitting position. The clinical assessment included standard measures of peripheral and auto-nomic neuropathy, but peripheral vascular disease was excluded by Doppler ultrasound. RESULTS — In supine position, TcPO2 was significantly reduced (means SE) in diabetic patients with foot at risk (6.04 0.52 kPa) compared with diabetic (7.14 0.43 kPa, P 0.035) and nondiabetic (8.10 0.44 kPa, P 0.01) control subjects. The sitting/supine TcPO2 differ-ence was higher in diabetic subjects with foot at risk (3.13 0.27 kPa) compared with both diabetic (2.00 0.18, P 0.004) and nondiabetic (1.77 0.15 kPa, P 0.0003) control subjects. The mean sitting/supine ratio was 1.70 0.12 in diabetic patients with foot at risk