Abdominal thrombotic complications following bariatric surgery.

Background: Thrombotic events involving the portal-splenic-mesenteric venous system (PSMVT) are rare but potentially lethal after bariatric surgery.

Objectives: To investigate the incidence, clinical presentation, management, and outcome of thrombotic events after bariatric surgery.

Setting: Two university hospitals.

Methods: A retrospective review of individuals who underwent bariatric surgery between January 2006 and December 2015.

Results: Overall, 4386 patients underwent bariatric surgery (laparoscopic sleeve gastrectomy [LSG; n = 2886], laparoscopic Roux-en-Y gastric bypass [n = 762], laparoscopic adjustable gastric banding [n = 668], and biliopancreatic diversion [n = 70]). Mechanical (thigh-length pneumatic compression stockings) and pharmacologic thromboprophylaxis (40 mg enoxaparin daily, starting 12 hours after surgery until discharge) was provided for all patients. A minority of patients (n = 543, 12.4%) also received an extended course of enoxaparin for 1-4 weeks after discharge. We observed 16 cases of PSMVT, all after LSG, with an incidence of .55% (16/2886). Twelve additional patients experienced deep vein thrombosis and 6 had pulmonary embolism. Follow-up imaging indicated complete resolution in all cases, with no sequelae, recurrent thrombosis, or mortality. The overall thrombosis rate was significantly lower in patients who received an extended course of anticoagulation after LSG (P = .01) and after any type of bariatric surgery (P = .02).

Conclusions: PSMVT was found to occur uncommonly after LSG. Prompt diagnosis and anticoagulation therapy led to favorable outcomes in most cases. Significantly lower rates of thrombosis were found in patients who received an extended course of anticoagulation. We support its use for at least 1 week after discharge.