Association of venous thromboembolism prophylaxis with postoperative bleeding in bariatric surgery: an observational study
In brief
A revised enoxaparin protocol did not significantly change bleeding after bariatric surgery
At one US hospital, clinically significant bleeding occurred in 2.3% of patients on the previous enoxaparin regimen and 3.0% after a protocol change, which used a higher dose during surgery but a lower once-daily dose afterward. Gastric bypass and lower body mass index were linked to more bleeding, but this observational study cannot establish causes or show whether dose adjustments would reduce risk.
- Journal
- Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery (Q1)
- Published
- 21 September 2026
- Study design
- Cohort / observational study
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Kate V Lauer, Jamie Ho, Dawda Jawara, Mads Owen, Andre Acra, Megha Brahmbhatt, et al.
- PMID
- 42869679
- DOI
- 10.1016/j.soard.2026.08.030
Why clinicians should know about it
- Picked for Bariatric and Metabolic Surgery (top studies of the week, 18 October 2026): VTE prophylaxis protocol, bleeding outcomes in sleeve gastrectomy and gastric
Abstract
BACKGROUND: Patients undergoing bariatric surgery are at an increased risk of postoperative venous thromboembolism (VTE). VTE prophylaxis protocols vary and can contribute to postoperative bleeding. OBJECTIVE: Evaluate whether implementation of a VTE prophylaxis protocol is associated with a change in frequency of postoperative bleeding after bariatric surgery. SETTING: Single United States university hospital. METHODS: Patients who underwent sleeve gastrectomy or gastric bypass between 2020 and 2024 were assigned to the preprotocol or postprotocol group based on the date of surgery. Preprotocol patients received 40 mg of enoxaparin intraoperatively followed by 40 mg twice daily, whereas postprotocol patients received 60 mg of enoxaparin intraoperatively followed by 60 mg daily. Frequency of bleeding requiring transfusion and/or endoscopic or surgical intervention was compared using Fisher exact tests. A multivariable analysis identified characteristics associated with bleeding. RESULTS: Six hundred sixty preprotocol and 797 postprotocol patients met inclusion criteria (mean [standard deviation] age, 45.4 [10.8] years; 85.5% White; 82.0% female; 60.6% sleeve gastrectomy). Bleeding frequency was similar between groups (2.3% preprotocol versus 3.0% postprotocol; P = .419). A multivariable analysis revealed that gastric bypass was associated with increased odds of bleeding (odds ratio, 1.94; confidence interval, 1.02‑3.70; P = .044), whereas higher body mass index was associated with decreased odds (odds ratio, .50; confidence interval, .29‑.87; P = .015). CONCLUSIONS: A standardized VTE prophylaxis protocol using a higher intraoperative enoxaparin dose but lower total once daily dose was not superior to a twice daily regimen in regards to the frequency of clinically significant bleeding. These results suggest that protocolized prophylaxis can be applied safely but that patients with lower preoperative weights may be at a higher risk of bleeding and warrant dose adjustment.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.