The effect of prophylactic heparinization on the venous blood flow using the Doppler ultrasonic flowmeter

The effect of prophylactic heparinization on the postoperative venous blood flow was prospectively studied in 100 lower limbs of 50 patients. Patients were randomized into two groups of 25 patients each: a control group and a heparin group. Changes in the venous blood flow were monitored using the Doppler ultrasonic flowmeter. The study illustrated the protective role of prophylactic heparinization in maintaining a near normal venous blood flow after surgery. The postoperative reduction in venous blood flow in heparinized patients was significantly less than the decrease in blood flow in non-heparinized patients during the same postoperative period. This significant difference between the two groups of patients applied to the steady and the augmented blood flow rates. The beneficial role of prophylactic heparinization was shown to act significantly in patients undergoing minor surgery, in obese subjects and in those suffering malignant disease. Patients undergoing major surgery also benefited significantly from prophylactic heparinization apart from their steady venous blood flow during the first postoperative day.