Post discharge prophylactic anticoagulation in gastric bypass patient-how safe?

It is becoming an increasingly common practice to discharge gastric bypass (GBP) patients on prophylactic anticoagulation. This is because pulmonary embolism (PE) is a common cause of mortality postoperatively. This study was undertaken to: (1) determine the incidence of major bleeding in GBP patients discharged on prophylactic low molecular weight heparin (LMWH)-enoxaparin and, (2) correlate the bleeding risk to the dose used.

Retrospective chart review of all open GBP operation from June 2004 to August 2005. One hundred and twenty seven patients were sent home on LMWH for 2 weeks.

Body mass index (BMI) > or =50 kg/m(2) with chronic venous stasis and/or obstructive sleep apnea, previous history of PE or deep vein thrombosis (DVT) or BMI > or =60 kg/m(2). The study group was divided into two subgroups: 40 mg twice daily (bid) and 60 mg bid LMWH. Statistical analysis was done with the chi-square. The primary outcome measure was major bleeding; defined as bleeding during the period of LMWH use associated with symptomatic decrease in hematocrit (HCT), necessitating stopping LMWH administration before the end of the study period (2 weeks), bleeding-related readmission, blood transfusion, or intervention. Excluded were patients on warfarin or treated with therapeutic LMWH.

The groups were similarly matched for age, body mass index, and risk factors. No episode of major bleeding after discharge occurred in either group.

The use of low molecular weight heparin for prophylactic anticoagulation after open gastric bypass is not associated with risk of major bleeding.