Assessment of lower limbs edema in healthy workers who are exposed to long-term gravity

Abstract

The aim of this study is to establish changes in leg volumes in healthy subjects (HS) after prolonged standing and prolonged lying. The study was carried out on two HS groups: the group A (20 subjects) included physicians and nurses who underwent a water plethysmography test, before and after eight hours of standing still in the operating room. The group B (20 subjects) included volunteers who were assessed before and after 10 h of supine resting. Group A: baseline leg volume was 1857.5 mL±196.9 on the right and 1850 mL±194.7 on the left limb. After eight hours of hydrostatic pressure action the two lower limbs volume was significantly increased to 1945 mL±209.6, and to 1940 mL±216.2, respectively (P<0.0001). The increased volume is significantly correlated with time (R2=0.95, P<0.0001). Group B: baseline leg volume was 1875 mL±175.1 on the right, and 1862.5 mL±166.9 on the left limb. After ten hours of resting supine the volume was 1770 mL±195.6, and to 1757.5 mL±194.2, respectively (P<0.0001). The decreased volume is significantly but inverted correlated with time (R2=−0.98, P<0.0001). This study demonstrates how the hydrostatic pressure is a main determinant for fluid accumulation in the lower extremity. To counteract the gravitational gradient becomes the mandatory prophylactic approach for healthy individuals who are exposed to an increased chronic venous disease risk.

Keywords

• edema, posture, circadian variability, gravity, water plethysmography.