March 1993

Unexpectedly High Rate of Phlebographic Deep Venous Thrombosis Following Elective General Abdominal Surgery Among Patients Given Prophylaxis With Low-Molecular-Weight Heparin

Author Affiliations

From the Department of Medicine, Unit of Angiology (Drs Bounameaux and Khabiri), the Clinic of Digestive Surgery, Department of Surgery (Drs Huber and Rohner), and the Division of Radiodiagnostics, Department of Radiology (Drs Schneider and Didier), University Hospital of Geneva (Switzerland).

Arch Surg. 1993;128(3):326-328. doi:10.1001/archsurg.1993.01420150082015

• One hundred ninety-four patients undergoing elective general abdominal surgery were randomized in a single-blind study to receive one daily subcutaneous injection of a low-molecular-weight heparin, dalteparin sodium (2500 IU, n=97) or nadroparin calcium (3075 IU, n=97), two regimens that are approved in Europe to prevent deep venous thrombosis. On the eighth postoperative day, bilateral ascending leg phlebography (n=185) showed the presence of deep venous thrombosis in 45 cases (24.3%; 95% confidence interval, 18% to 31%), with a significantly higher rate (on intention-to-treat) among the patients who received the lower dosage (30 vs 15 deep venous thromboses). We conclude that the two regimens of low-molecular-weight heparin that were used in this study failed to prevent postoperative phlebographically proved deep venous thrombosis in one of four patients.

(Arch Surg. 1993;128:326-328)