Changes in skin blood flow in ischaemic limbs after vascular reconstruction measured by fluorescein flowmetry and laser Doppler flowmetry.

It is not known to what extent the skin blood flow increases after vascular reconstruction in ischaemic limbs. Thus, a study was undertaken to measure skin blood flow, using the two techniques laser Doppler flowmetry and fluorescein flowmetry, before and after vascular reconstruction. The skin temperature was measured also. The plantar circulation was assessed in 14 patients (9 non-diabetics and 5 diabetics; mean age 65 years; range 47-80), with the patient in the supine position, 1-2 days before and 8-10 days after surgery. After vascular reconstruction the skin blood flow increased by 240% (P < 0.01) when measured by fluorescein flowmetry and by 148% (P < 0.01) when measured by laser Doppler flowmetry, and the skin temperature rose by 3.2 degrees C (P < 0.01). In the contralateral non-operated limb there was no significant change in skin blood flow as measured by the two methods. The results imply that after vascular reconstruction in ischaemic limbs the skin blood flow increases both in the superficial layer as determined by fluorescein flowmetry (which measures the blood flow down to 0.6 mm) and in deeper layers as determined by laser Doppler flowmetry (which measures flux down to 6 mm).