Objective: High-risk patients are at significant risk for venous thromboembolism (VTE) and may benefit from the addition of retrievable inferior vena cava filters (rIVCF) to chemoprophylaxis. However, the optimal VTE prophylaxis has not been established in morbidly obese patients undergoing bariatric surgery. This observational study examines the use of rIVCFs in combination with chemoprophylaxis for high-risk bariatric surgery patients.
Methods: A retrospective review was performed of all high-risk morbidly obese patients who underwent bariatric surgery between February 2007 and July 2009. Patients were considered high-risk for the development of a peri-operative VTE if they had a prior history of VTE, a BMI≥ 55 kg/m2, were severely immobile, or had preexisting hypercoaguable condition. All patients underwent a preoperative venous duplex study. RIVCF placement was performed preoperatively on the day of the bariatric procedure. Standard chemoprophylaxis was initiated preoperatively and continued throughout the hospital stay. Clinical, demographic, operative and postoperative data were recorded. A venogram was performed prior to removal of the rIVCFs.
Results: Forty-four patients (12 men and 32 women) with a mean age of 47.9 ± 12.1 years and a mean BMI of 58 ± 9.5 kg/m2 underwent roux-en-y gastric bypass with concomitant rIVCF placement. Mean follow up was 184 days. One patient (2.3%) was found to have a deep venous thrombosis (DVT) on preoperative venous duplex. All patients received VTE chemoprophylaxis preoperatively and successful rIVCF placement. Indications for rIVCF placement were BMI (68%), history of prior VTE (30%), and/or severe immobility (2%). The operation was performed laparoscopically in 41 patients (93%). Three patients (two revisional surgeries and one conversion secondary to intestinal adhesions) underwent open gastric bypass. The mean operative time was 111.1 ± 30.2 minutes and the mean length of stay was 3.2 ± 1.2 days. A postoperative venous duplex for the clinical suspicion of VTE was performed in four patients (9%), of which 2 were positive for the presence of a DVT. Retrieval was successful in 25 patients (57%). A venogram was performed prior to removal of each rIVCF. No significant thrombus was found, however, one filter had migrated to the right common iliac vein. Overall, there were two complications of rIVCF placement (4.5%), one during insertion and the other due to migration. One mortality (2%) occurred as the result of an arrhythmia; no pulmonary emboli were found.
Conclusions: This study documents that rIVCFs in high-risk bariatric surgery patients is associated with a low incidence of DVT (4.5%) and filter-related complications (4.5%) without pulmonary emboli. However, a significant portion of patients continue to have their filters in place. Long term effects of rIVCFs in patients who do not undergo retrieval are largely unknown. These long term effects need further investigation in order to appreciate the true benefit of rIVCFs in this patient population.
Session: Podium Presentation
Program Number: S055