Incidence and Associated Risk Factors of Venous Thromboembolism After Open and Laparoscopic Nephrectomy in Patients Administered Short-period Thromboprophylaxis: A Danish Nationwide Population-based Cohort Study

Objective: To report the incidence of venous thromboembolism (VTE) after nephrectomy in Denmark and explore associated risk factors. Materials and Methods: A nationwide population-based retrospective cohort study was performed. All nephrectomies from January 2010 to August 2018 were assessed for postoperative VTE events. Univariable and multivariable analyses were used to evaluate the odds ratio (OR) of clinical variables’ effect on postoperative VTEs, within 4 weeks and 4 months after nephrectomy. Results: In 5213 nephrectomized patients, postoperative VTE incidence was 1% and 2% within 4 weeks and 4 months, respectively. Multivariable analyses revealed that predictors of postoperative VTE within 4 months were: open nephrectomy (OR 2.5, P =.001), history of VTE (OR 13.3, P <.001), length of hospital stay (OR 0.98, P =.02), and lymph node dissection (OR 2.0, P =.04). Limitations included the retrospective and registry-based study design and absence of individual patient data on patient body mass index and length of surgery. CONCLUSION: For nephrectomy, postoperative VTE is rare. Open nephrectomy, history of VTE, length of hospital stay, and lymph node dissection are important risk factors which should be evaluated when tailoring VTE prophylaxis regimens.