New parameters for evaluation of blood flow in patients with leg ulcers

Three new parameters have been introduced to provide data for quantitative evaluation of peripheral cutaneous blood flow in patients with leg ulcers. Reactive hyperemia was induced by occlusion of the blood flow for four minutes at the thigh-level. Blood flow was subsequently measured by laser-Doppler velocimetry in an unselected group of 14 patients with leg ulcers and a matched control group. The parameters used for evaluation was: 1) "peak flow" f(p), 2) divided by time to "peak flow" t(p), rendering a rate constant k (k = f(p)/t(p)) expressing the ability to increase blood flow abruptly in case of need. These parameters were all significantly reduced in the patients with leg ulcers, indicating that this simple and atraumatic technique was useful for discriminating blood flow values that may be relevant for healing time and with a sensitivity comparable to the measurements of distal systolic blood pressure. Distal systolic blood pressure measurements can still be considered to be of value when screening for arterial insufficiency in patients with leg ulcers. The values obtained were significantly lower in 36 patients with leg ulcers compared with 9 age-matched control persons.