Pneumatic thigh compression reduces calf volume and augments the venous return.

Objectives: Reactive hyperaemia following thigh compression increases arterial inflow and venous outflow. The net effect can be measured by changes in calf volume quantified using air-plethysmography. The objective was to investigate the effect of thigh compression on venous return.

Method: The right legs of 19 consecutive volunteers (14 male), median age 31 (25-56) years, were studied in the supine position using air-plethysmography. The clinical, etiological, anatomical, pathophysiological (CEAP) class was C0. A thigh-cuff, 12 cm wide, was inflated in increments of 10 mmHg, from 0 to 80 mmHg. After each inflation step, the calf volume increased to a plateau and was recorded. At 80 mmHg, the thigh-cuff was deflated suddenly with the calf volume decreasing until baseline. Calf volume changes were recorded and stored for analysis.

Results: There was a stepwise increase in the venous volume of the calf with each incremental rise in thigh-cuff pressure up to 80 mmHg (p < .0005, Friedman). The median (interquartile range) increase in venous volume from 0 to 80 mmHg was 87 (65-113) mL (p < .0005, Wilcoxon). The volume change below the original baseline following thigh-cuff release was -16 (-12 to -25) mL (p < .0005, Wilcoxon).

Conclusions: Once optimised, intermittent pneumatic compression of the thigh may have a therapeutic role in augmenting the venous return and reducing leg swelling in patients.