Efficacy of venous thromboembolism prophylaxis in morbidly obese patients undergoing gastric bypass surgery

Background: Patients undergoing gastric bypass are at risk of developing venous thromboembolism (VTE) due to multiple risk factors including obesity and abdominal surgery. The purpose of this study is to evaluate the effectiveness of inpatient VTE prophylaxis in morbidly obese patients undergoing gastric bypass and the incidence of symptomatic VTE following discharge. Methods: A retrospective chart review of patients undergoing gastric bypass from August 2000 to August 2001 was performed. Inpatient charts from medical records and physician outpatient office charts were reviewed. Evaluation consisted of: VTE prophylaxis utilized, acquired risk factors for VTE, BMI, development of deep venous thrombosis (DVT) or pulmonary embolism (PE) during hospitalization, outpatient office visits following discharge, and VTE after discharge. Results: 107 patient charts were reviewed. There were no incidences of VTE documented during hospitalization, and only one patient developed a symptomatic DVT after discharge. During hospitalization, all patients received DVT prophylaxis consisting of medical management, external compression devices, and ambulation orders. At the time of surgery, patients had a mean age of 40 years (23 - 69 years) and a BMI of 51.3 kg/m(2) (37 - 82). Surgery lasted a mean of 108.9 minutes (65 - 305), patients were hospitalized for a mean of 4.3 days (3 - 7), and had a mean of 3.4 risk factors (2 - 7 risk factors) for the development of VTE. After hospital discharge, 101 patients were followed for the development of VTE. Conclusion: Combination of medical management, early ambulation, and external compression devices adequately prevented the development of VTE in patients after gastric bypass.