EFFECT OF LIGHTWEIGHT COMPRESSION STOCKINGS ON VENOUS HEMODYNAMICS

Objective. To investigate the effect of lightweight graduated elastic stockings on venous haemodynamics. Design. The amount of reflux and fu nction of the calf muscle pump were evaluated before and after the app lication of lightweight graduated compression stockings using air-plet hysmography. Each patient acted as his own control and the Wilcoxon ra nk sum test was used. Setting. Vascular laboratory of a teaching hospi tal. Subjects. 19 female patients (20 limbs) with moderate varicose ve ins. Main outcome measures. The haemodynamic parameters: amount of ref lux (VFI), ejection fraction (EF) of the calf muscle pump after one ti ptoe exercise, residual volume fraction (RVF) after 10 tiptoes and ven ous volume (VV) were determined for each patient with and without the three strengths of stocking (7, 10, 14 mmHg at the ankle) using air-pl ethysmography. Results. The mean VFI decreased from 5.7 ml/sec without stockings to 4.6+/-2.2, 3.9+/-2.3, and 3.4+/-1.8 with stockings of 7, 10 and 14 mmHg respectively (p<0.0002). Similarly the RVF showed a si gnificant decrease with all three stockings from the initial value 42. 3% to 36.3, 34.4 and 31.5 respectively (p<0.03). EF showed an increase from 49.2% to 51.4, 50.9 and 56, but only with the latter was the inc rease significant (p<0.02). VV decreased from 118.8 ml to 113.6+/-24.4 (p>0.05), 104.2+/-22.8 and 109.1+/-27.4 (p<0.008) with 10 and 14 mmHg .Conclusions. The results indicate that lightweight compression stocki ngs can have a significant effect on venous haemodynamics. They decrea se the residual volume fraction and by inference ambulatory venous pre ssure. This is the result of an increase in the ejection fraction with a decrease of reflux. The results offer a possible physiological expl anation on the relief of symptoms experienced when patients with varic ose veins wear lightweight stockings.