Preoperative normovolaemic haemodilution with dextran 70 as a thromboembolic prophylaxis in total in hip replacement.

The effect of preoperative normovolaemic haemodilution with dextran 70 in 57 patients undergoing total hip replacement for osteoarthritis, was evaluated with respect to the production of thrombosis and pulmonary embolism. The patients were randomly allocated to one group undergoing preoperative haemodilution and one control group receiving 500 ml dextran 70 during operation and again on the second postoperative day. Before operation blood was replaced by dextran 70 to lower the hematocrit to between 25 and 30. The blood drained from the patients was used to replace blood lost at operation. Between 10 and 14 days after operation the patients were examined by perfusion lung scan, chest radiography and bilateral phlebography. Twelve patients also had 133Xe ventilation scans. The incidence of deep vein thrombosis in the two groups did not differ significantly. Pulmonary embolism was significantly decreased in the preoperative haemodilution group. One patient in the control group had clinical symptoms of, and died from, pulmonary embolism.