Current practices in the prophylaxis of venous thromboembolism in bariatric surgery

Background: Morbidly obese patients undergoing bariatric surgery have commonly been concluded to be at high risk for the development of perioperative venous thromboembolism. Due to its clinically silent nature, primary prevention is the key to reduce morbidity and mortality. There is no clear consensus in the literature regarding the optimum approach to minimize this preventable phenomenon. Methods: Members of the American Society for Bariatric Surgery were surveyed regarding their current practices in the prophylaxis of venous thromboembolism in their bariatric patients. Results: 31% of the members completed the survey. 62% were in private practice, and 38% practiced in an academic hospital. The number of bariatric surgeries done per year ranged from 5 to 325, with a mean of 85 procedures per member. The gastric bypass was the most commonly performed procedure at 61.7%, followed by vertical banded gastroplasty at 23.3%, biliary pancreatic diversion at 9.3%, laparoscopic gastroplasty at 4.0%, laparoscopic gastric bypass at 1.6%, and horizontal banded gastroplasty at 0.1%. 86% felt that their bariatric patients were at high risk for developing deep vein thrombosis (DVT) and pulmonary embolism (PE) with a self-reported incidence of 2.63% and 0.95%, respectively. 48% had at least one death due to PE. Routine prophylaxis is used by over 95% of members. 62% ranked the various methods of prophylaxis from most preferred to least preferred, while 38% used a combination of 2 or more prophylactic methods simultaneously. Low-dose heparin was the most preferred prophylaxis by 50% of members, followed by intermittent pneumatic compression stockings at 33%, low molecular weight heparins at 13%, and other methods at 4%. Over 83% indicated that safety with few complications, ease of administration, and effectiveness were the most important criteria for selecting their most preferred prophylactic method. Only 2% routinely performed testing to rule out venous thromboembolism before discharge, and 11% routinely discharged patients with prophylaxis. Conclusions: The prevailing opinion of members of the American Society for Bariatric Surgery is that morbidly obese patients are at high risk for developing perioperative venous thromboembolism. A vast majority routinely use prophylaxis. Despite these measures, fatal PE is still widespread. A lack of consensus in the method of prophylaxis was seen. A multicentric randomized controlled study comparing the efficacy of the various methods of prophylaxis will be the only manner to determine the best prophylaxis and its usefulness. This study will be costly and probably not warranted due to the low incidence of this condition in the morbidly obese patient.