EFFECT OF LEG ELEVATION ON THE SKIN MICROCIRCULATION IN CHRONIC VENOUS INSUFFICIENCY

Purpose: Leg elevation is advised in the treatment of venous disease a ssociated with edema. We have used laser Doppler fluxmetry to assess t he effects of leg elevation on the skin microcirculation. Methods: Fif teen patients with lipodermatosclerosis caused by chronic venous insuf ficiency and 15 control subjects were studied. Measurements were made from the liposclerotic skin of patients and 8 cm above the medial mall eolus in control subjects. Laser Doppler flux, blood cell velocity, an d concentration of moving blood cells were recorded with the subject l ying in the supine position and after elevating the foot 30 cm above t he heart level. Results: In subjects in the horizontal position, the r esting laser Doppler flux was significantly higher in patients with li podermatosclerosis than in control subjects (median difference 63 arbi trary units; 95% confidence interval: 36, 108). This difference was du e to a higher concentration of moving blood cells in the patient group (median difference 6.5 arbitrary units; 95% confidence interval: 3.4, 9). The blood cell velocity was not statistically significant between the two groups. On leg elevation, there was a substantial increase in the laser Doppler flux in the patient group; the median percentage in crease in flux was 45% (p < 0.01). This was due to an increase in bloo d cell velocity; the median percentage increase was 41% (p < 0.01). Th ere was no corresponding change in the concentration of moving blood c ells. The results in the control group showed a similar trend but have not reached statistical significance. Conclusion: We conclude that li mb elevation enhanced the microcirculatory flow velocity in liposclero tic skin of patients with chronic venous insufficiency.