Abdelrahman A. Nimeri AA, et al. Clin Appl Thromb Hemost. 2015
5-Year Follow-Up of an American College of Surgeons National Surgical
Quality Improvement Program.
Patient presenting for bariatric surgery are at a varying degree of risk for venous thrombo-embolism (VTE). This variable risk make systematic risk assessment necessary to decide the dose of chemo prophylaxis needs and the need for chemo prophylaxis after discharge. Currently, the ASMBS has produced a position statement and standard of care for VTE in bariatric surgery patients. In this document all bariatric surgery patients are considered at a moderate or high risk for VTE and recommends chemo prophylaxis for patients after bariatric surgery.1 However, the doses and duration are left for the bariatric surgeons to decide due to the lack of level I evidence.
Recently, a large study from the Michigan collaborative group have shown that low molecular weight heparin (LMWH) is more effective than subcutaneous heparin (SC heparin) for bariatric surgery patients in reducing VTE without an increased risk of bleeding2. In addition, the same group questioned the utility of IVC filters in patients undergoing bariatric surgery in another study3. In addition, a systematic review did not find the benefits of IVC filter outweigh the risks4.
Figure 1 (Caprini VTE risk assessment electronic medical record version):
At BMI Abu Dhabi, we assess the risk for VTE in all patients who are undergoing bariatric surgery on admission and on discharge utilizing the well-validated Caprini scoring system (figure 1). If the patients have a score of 4 which is the vast majority of our patients then they receive LMWH 40 mg BID during the hospital stay only and for two weeks after discharge if the score is more than 4. In addition, for patients with BMI >60 we utilize a higher dose of LMWH up to 60 mg BID and measure their Anti factor Xa levels prior to discharge to guide their therapy and dose for the first two weeks after discharge. Since the introduction of this mandatory risk assessment system, we have been able to reduce our rates of VTE and PE significantly in our bariatric surgery patients5.
- ASMBS updated position statement on prophylactic measures to reduce the risk of venous thromboembolism in bariatric surgery patients The American Society for Metabolic and Bariatric Surgery Clinical Issues Committee* Surgery for Obesity and Related Diseases 9 (2013) 493–497.
- Birkmeyer NJ, Finks JF, Carlin AM, Chengelis DL, Krause KR, Hawasli AA, Genaw JA, English WJ, Schram JL, Birkmeyer JD; Michigan Bariatric Surgery Collaborative. Comparative effectiveness of unfractionated and low-molecular-weight heparin for prevention of venous thromboembolism following bariatric surgery. Arch Surg. 2012 Nov;147(11):994-8. doi: 10.1001/archsurg.2012.2298.
- Inferior vena cava filters for prevention of venous thromboembolism in obese patients undergoing bariatric surgery: a systematic review.Rowland SP1, Dharmarajah B, Moore HM, Lane TR, Cousins J, Ahmed AR, Davies AH. Ann Surg. 2015 Jan;261(1):35-45. doi: 10.1097/SLA.0000000000000621.
- Birkmeyer NJ1, Finks JF, English WJ, Carlin AM, Hawasli AA, Genaw JA, Wood MH, Share DA, Birkmeyer JD; Michigan Bariatric Surgery Collaborative. Risks and benefits of prophylactic inferior vena cava filters in patients undergoing bariatric surgery. J Hosp Med. 2013 Apr;8(4):173-7. doi: 10.1002/jhm.2013. Epub 2013 Feb 8.