Incidence of Venous Thromboembolism Following Major Emergency Abdominal Surgery.

BACKGROUND: In a retrospective cohort study, we looked at the incidence and risk factors of developing in-hospital venous thromboembolism (VTE) after major emergency abdominal surgery and the risk factors for developing a venous thrombosis. METHODS: Data were extracted through medical records from all patients undergoing major emergency abdominal surgery at a Danish University Hospital from 2010 until 2016. The primary outcome was the incidence of venous thrombosis developed in the time from surgery until discharge from hospital. The secondary outcomes were 30-day mortality and postoperative complications. Multivariate logistic analyses were used for confounder control. RESULTS: In total, 1179 patients who underwent major emergency abdominal surgery during 2010-2016 were included. Thirteen patients developed a postoperative venous thromboembolism (1.1%) while hospitalized. Eight patients developed a pulmonary embolism all verified by CT scan and five patients developed a deep venous thrombosis verified by ultrasound scan. Patients diagnosed with a VTE were significantly longer in hospital with a length of stay of 34 versus 14 days, P < 0.001, and they suffered significantly more surgical complications (69.2% vs. 30.4%, P = 0.007). Thirty-day mortality was equal in patients with and without a venous thrombosis. In a multivariate analysis adjusting for gender, ASA group, BMI, type of surgery, dalteparin dose and treatment with anticoagulants, we found that a dalteparin dose ≥5000 IU was associated with the risk of postoperative surgical complications (odds ratio 1.55, 95% CI 1.11-2.16, P = 0.009). CONCLUSION: In this study, we found a low incidence of venous thrombosis among patients undergoing major emergency abdominal surgery, comparable to the incidence after elective surgery.