The Effect of Compression on Venous Haemodynamics Assessed by Quantitative Photoplethysmography

Abstract

Background: The purpose of this study was to examine quantitatively the effect of compression stockings on venous haemodynamics at the level of the ankle. Methods: To obtain quantifiable results, a computer-controlled photoplethysmographic system was used to measure the displacement of local blood volume induced by exercise (exercise displacement volume, EDV) and by tilting the subject (tilt displacement volume, TDV). The test was repeated after application of class I compression stockings 20–30 mmHg). The ratio EDV/TDV is considered to represent the efficiency of the veno-muscular pump. Three groups of subjects were studied: a control group ( n = 8), patients with telangiectases ( n = 10) and a group with large varices ( n = 11). Results: The application of external compression had a quantifiable and beneficial effect on venous haemodynamics and was most significantly documented by an increase in veno-muscular efficiency (EDV/TDV) from 28% to 44% in the varicose vein patients. Statistically significant increases of EDV/TDV could also be identified in the telangiectatic patients and normal subjects. EDV also showed an increase with compression stockings; however, statistical significance was only reached in the varicose vein group. Conclusion: External compression (class 1 compression stockings) significantly improved venous haemodynamic indices, especially in patients with varicose veins. Quantitative photoplethysmography used in this study permits a fast, non-invasive and quantifiable evaluation of venous haemodynamics of the lower extremities.