Perioperative Venous Thromboembolism Prophylaxis After Bariatric Surgery

Abstract

Obesity is both an independent and an additive risk factor for venous thromboembolism (VTE) [1, 2]. This is attributed to elevated levels of leptin, tissue factor, coagulation factors VII and VIII, thrombin, fibrinogen, von Willebrand factor, plasminogen activator inhibitor 1 that cause hypercoagulability [3]. Dyslipidemia, hyperglycemia, inflammation, oxidative stress and endothelial dysfunction associated with obesity may also be contributory [3]. Patients undergoing bariatric surgery for morbid obesity are at increased risk for VTE in the perioperative period [4]. A retrospective cohort study showed that bariatric patients had a mean of 3.4 risk factors (ranging from 2 to 7 factors) for the development of VTE [5]. Thus all patients are atleast at a moderate to high risk for VTE. The reported incidence of symptomatic VTE in bariatric surgery series is approximately 1–5.4 % for open surgery and <1 % for laparoscopic surgery. VTE is also a leading cause of mortality after bariatric surgery. In an autopsy study of 10 RYGB patients by Melinek et al, 3 out of 10 postoperative mortalities were directly a result of PE and 8 out of 10 patients had microscopic evidence of PE at autopsy despite the use of prophylaxis [6].