Background

Bariatric surgery venous thromboembolism (VTE) prescribing practices vary widely. Our institutional VTE prophylaxis protocol has historically been unstandardized. We aim to: 1) create a standardized VTE prophylaxis protocol for patients undergoing bariatric surgery, 2) track protocol compliance, and 3) identify barriers to compliance and address them with iterative Plan-Do-Study-Act (PDSA) cycles.

Methods

We conducted a retrospective study at a single academic hospital for all patients undergoing bariatric surgery (1/2019-2/2022). A multidisciplinary group of bariatric clinicians reviewed the literature and developed the following standardized VTE prophylaxis protocol: 1)5000 units preoperative subcutaneous (SC) heparin, 2)40mg SC low molecular weight heparin (LMWH) 9pm on postoperative day (POD) 0, 3)40mg SC LMWH starting POD1 daily for patients with BMI<40 and twice daily for patients with BMI≥40. This protocol was distributed to all relevant clinicians. We assessed monthly compliance rates through chart review. Goal compliance was 90%. We identified underlying barriers to compliance from 2/2020 to 9/2022. We addressed these barriers interventions per the PDSA method.

Results

A total of 796 patients were included. Preoperative heparin administration rates increased from 47% pre-intervention to 96% post-intervention (Figure 1A, p<0.0001). There was a 23% protocol defect rate (n=182/796). Key barriers to protocol compliance included orderset timing errors (n=45), surgeon error (n=44), surgeon discretion (n=40), and patient refusal (n=26; Figure 1B). There was no change in bleeding or VTE rates during the study period.

Conclusions

A standardized VTE prophylaxis protocol improved compliance rates significantly. Persistently identifying and overcoming compliance obstacles enabled maintenance of long-term high compliance.