Subcutaneous ancrod in prevention of deep vein thrombosis after hip replacement surgery

In a randomised double-blind controlled trial we have assessed the use of ancrod ('Arvin') in the prophylaxis of deep vein thrombosis (DVT) in patients undergoing hip replacement surgery. Thirty-five patients received daily subcutaneous injections of ancrod and 38 patients received saline injections. DVT was detected by bilateral ascending venography (67 patients) 7-19 days after surgery. The frequency of major femoral DVT (greater than or equal to 5 cm long) was significantly reduced from 18 thrombi in the limbs of the placebo group to 5 in the ancrod group (p less than 0.01). The overall frequency of thrombi including calf DVT was not significantly different between the two groups. Four patients within the ancrod group had evidence of wound bleeding, compared with 2 placebo patients. One patient had a bleeding event which was considered severe enough to require cessation of ancrod injections.