A low molecular weight heparin (KABI 2165) for prophylaxis of postoperative deep venous thrombosis.

In a prospective double-blind trial, low molecular weight (LMW) heparin (KABI 2165) 5,000 U (anti-Xa) once daily was compared with conventional heparin 5,000 IU twice daily, both given subcutaneously, as regards prevention of postoperative deep venous thrombosis (DVT) in 52 patients undergoing major abdominal surgery. Radioactive fibrinogen uptake test (FUT) was used for DVT screening. DVT, diagnosed from positive FUT, developed in two patients from each group, but could be phlebographically confirmed in only one (LMW) case. No intergroup differences were found in peroperative blood loss or requirements for blood transfusion. Complications attributable to the prophylactic regimens were few. In the LMW-heparin group, the anti-Xa levels measured during operation showed considerable variation, the higher activities (greater than 0.30 U/ml) being nonsignificantly associated with increased blood loss. Studies with lower doses of LMW-heparin are recommended.