Significance of preoperative screening of deep vein thrombosis and its indications for patients undergoing urological surgery.

Purpose: Preoperative deep vein thrombosis (pre-DVT) is a risk of symptomatic venous thromboembolism (VTE) and a serious postoperative surgical complication. However, little is known about pre-DVT in patients undergoing surgery. This study aimed to investigate the incidence and screening criteria of pre-DVT in patients undergoing urological surgery.

Materials And Methods: Between 2015 and 2017, 320 patients admitted to our hospital for urological surgery were included in this retrospective study. All patients underwent preoperative D-dimer testing. Patients with elevated D-dimer (≥1.0 μg/mL) levels underwent lower-limb compression ultrasonography (CUS). Clinical parameters were analyzed as predictors of pre-DVT, and modest cutoff value of D-dimer to predict pre-DVT were evaluated.

Results: Of 320 patients, preoperative elevated D-dimer levels and DVT were found in 81 (25.3%) and 20 (6.3%) patients, respectively. The positive predictive value (PPV) was 24.7% (20/81). ROC curve analysis revealed a cutoff D-dimer level of 1.8 μg/mL, yielding a PPV of 40.7% for pre-DVT among patients with elevated D-dimer levels. Preoperative DVT was detected in 16 (7.6%, n=210) patients with malignancy, 3 (5.7%, n=53) with adrenal tumors, and in 1 (1.8%, n=57) kidney donor. An age of >70 years was significantly associated with risk for pre-DVT (odds ratio, 2.81; 95% confidence interval, 1.12-7.19; p=0.0270). During a postoperative follow-up period of 90 days, no patient developed symptomatic VTE.

Conclusions: The incidence of pre-DVT was 6.3% in patients undergoing urological surgery. Elderly patients and/or a cutoff D-dimer level of 1.8 μg/mL might be good indications for pre-DVT screening by CUS.