Incidence and risk factors of venous thromboembolism after percutaneous nephrolithotomy: a single-center experience

Purpose To determine the incidence and risk factors of the venous thromboembolism (VTE) in patients undergoing percutaneous nephrolithotomy (PCNL). Methods We retrospectively reviewed the records of 896 consecutive cases receiving PCNL between July 2018 and August 2020 in our institution. Univariate analysis was performed to identify the risk factors of VTE, and multivariate logistic regression analysis was further performed to determine the independent risk factors. Furthermore, the corresponding nomogram was conducted to establish a predicted model for VTE. Results The overall incidence of VTE was 2.8%. The multivariate logistic regression analysis showed that discontinued anticoagulant or antiplatelet therapies (OR 4.505, 95% CI 1.410-14.401), increased postoperative 12-h d-dimer (OR 11.162, 95% CI 2.370-52.574), hydronephrosis (OR 3.303, 95% CI 1.303-8.375), higher Caprini risk assessment model (RAM) score (OR 3.233, 95% CI 1.207-8.659) and postoperative sepsis or septic shock (OR 3.784, 95% CI 1.163-12.306) were independent risk factors of VTE following PCNL. Moreover, the area under the curve of postoperative 12-h d-dimer, hydronephrosis and Caprini RAM score was 0.826, 0.621 and 0.660, respectively. Based on the identified independent risk factors, the well-calibrated nomogram showed a moderate discriminative ability with concordance index 0.731. Conclusions 2.8% of patients developed VTE following PCNL. Regarding those patients who have independent risk factors in this study, due attention should be paid to the effective thromboprophylaxis and the early detection of VTE.