Evaluation of skin blood flow and venoarteriolar response in patients with diabetes and peripheral vascular disease by laser Doppler flowmetry

Skin blood flow in the distal foot was evaluated in patients with peripheral vascular disease and diabetes and compared with skin blood flow in normal volunteers by use of laser Doppler flowmetry. Resting blood flow (RBF) and standing blood flow (SBF) were recorded in a room at a constant temperature (20-22 degrees C). The RBF was found to be different in the five groups (normal, diabetics, patients with intermittent claudication, those with rest pain and those with impending gangrene. In diabetics RBF was significantly higher than in normal subjects. Even on standing, SBF in diabetics was higher and not different from RBF, indicating an ineffective venoarteriolar response (VAR). The VAR was also reduced in patients with claudication and was abolished in patients with rest pain and impending gangrene. In patients with rest pain SBF was increased. Laser Doppler flowmetry is a useful technique for evaluating skin perfusion in patients with peripheral arterial disease and for discriminating among different classes of patients.