Prospective analysis of the incidence of deep venous thrombosis in bariatric surgery patients

Background. Venous thromboembolism (VTE), manifest as deep venous thrombosis (DVT) or pulmonary embolus, remains an important complication in bariatric operation patients. Our purpose was to determine the incidence of VTE in a consecutive series of patients undergoing Roux-en-Y gastric bypass (RYGB) to guide appropriate therapy. Methods. We prospectively examined a consecutive series of RYGB patients with bilateral lower-extremity venous duplex scan (DS) preoperatively, on postoperative day (POD)#2, and approximately POD#14. Preoperative clinical information including history of VTE, intraoperative data, postoperative course, and complications were recorded. Heparin 5,000 U subcutaneously was administered before the operation and every 12 hours throughout hospitalization along with sequential compression devices. Ambulation was instituted on POD#1. Temporary caval filters were placed in patients with a history of VTE. Results. A total of 106 patients were examined. Body mass index was 51 +/- 8 kg/m(2) (range, 40-73 kg/m(2)). Laparoscopic RYGB was performed in 75%. Hospital length of stay was 2.5 +/- 0.6 days. One hundred patients had no history of VTE; none had a positive DS preoperatively or on POD#2. One patient had a positive POD#14 DS and a second patient had a superficial thrombophlebitis, but a negative DS for DVT (both patients were symptomatic). Six patients had a prior history of VTE; all underwent preoperative placement of a temporary caval filter. Of these 6 patients, 1 developed a new postoperative DVT and another patient had thrombus on the caval filter with a negative lower-extremity DS. Conclusions. Occult DVT was not observed preoperatively in RYGB patients, suggesting that routine preoperative DS is not necessary in the absence of VTE history. Prophylaxis of heparin and sequential compression devices appears satisfactory in preventing DVT with only a 1% incidence inpatients with no prior history of VTE. Two of the 6 patients with prior history of VTE showed evidence of thrombus postoperatively. Although a small number of patients, this finding suggests that a caval filter should be placed preoperatively in RYGB patients with a history of VTE.