Blood flow characteristics and tissue nutrition in apparently ischaemic feet.

Blood flow in the apparently ischaemic feet of patients with atherosclerotic peripheral vascular disease was only weakly pulsatile but the volume of the resting total foot blood flow was higher than normal. No biochemical evidence of overall regional ischaemia or tissue anoxia was found to explain the aetiology of chronic nutritional skin lesions in these clinically ischaemic feet. The physiological effectiveness of a regional blood flow ultimately depends on its ability to perfuse the tissues, and in this respect it is suggested that pulse and pressure are more important than mere volume. It is further suggested that ischaemic or anoxic nutritional skin lesions develop in the presence of localized tissue perfusion failure and not from any overall regional blood flow insufficiency.