Perimalleolar subcutaneous tissue pressure effects of elastic compression stockings.

Purpose: We hypothesized that the clinical benefit of elastic compression stockings (ECS) is at least in part due to an increase in subcutaneous pressure that may promote resorption of extracellular fluids, providing more efficient diffusion of oxygen and nutrients from the microcirculation to the skin and subcutaneous tissues.
Methods: To test this hypothesis we designed and standardized a device for measuring subcutaneous pressure in patients. We then measured the supine perimalleolar subcutaneous pressure from a single limb in four groups: group 1 consisted of control subjects (n = 8); group 2 consisted of patients with varicose veins and superficial venous insufficiency without lipodermatosclerosis or edema (n = 5); group 3 consisted of patients with deep venous insufficiency and lipodermatosclerosis but without edema (n = 8); and group 4 consisted of patients with deep venous insufficiency, lipodermatosclerosis, and clinically evident edema (n = 8). Measurements were made at baseline and after application of 20 to 30 mm Hg and 30 to 40 mm Hg ECS.
Results: There was no significant difference in the baseline subcutaneous pressure between the three groups without clinical edema (p > 0.05). Baseline perimalleolar pressure was elevated, however, in group 4 patients compared with groups 1, 2, and 3 (p < 0.05). All three groups with chronic venous insufficiency (CVI) (groups 2, 3, 4) demonstrated increases in subcutaneous pressure with application of ECS, which was statistically significant in groups 3 and 4. There was no difference between the increase in perimalleolar subcutaneous pressure induced by 20 to 30 mm Hg or 30 to 40 mm Hg ECS in groups 3 and 4.
Conclusions: Patients with CVI and edema have significant elevations in supine resting perimalleolar subcutaneous pressure compared with control subjects and patients with CVI without edema. Twenty to 30 mm Hg and 30 to 40 mm Hg ECS increased measured perimalleolar subcutaneous pressure in patients with CVI with and without clinical edema but not in control patients. These results suggest the mechanism of benefit of ECS in patients with CVI is due at least in part to an increase in subcutaneous pressure that may act to promote more efficient absorption of perimalleolar extracellular fluid.