Current guidelines do not sufficiently discriminate venous thromboembolism risk in urology

Purpose: Venous thromboembolism (VTE) is the leading cause of noncancer death following major cancer surgery. Current thromboprophylaxis guidelines do not address procedure-specific risk of venous thromboembolism for urological patients. This project was created to determine the risk and timing of VTE after major urological surgery and to evaluate if surgical procedure was an independent risk factor for VTE after adjusting for previously established risk factors.

Material and methods: The American College of Surgeons׳ National Surgical Quality Improvement Program was used to create a cohort of patients who received major abdominal or pelvic urologic surgery between 2006 and 2014. The primary outcome was postoperative VTE. A Caprini score was calculated for each patient in our study to determine the risk of VTE. Multivariable logistic regression analyses were performed to determine the association between patient and procedural factors with venous thromboembolism.

Results: During the study period, 65,100 patients were eligible and 956 patients (1.5%) developed a venous thromboembolism. More than half of VTE events occurred after hospital discharge (n = 570; 60%). Radical cystectomy had the highest risk of VTE (299/5,976; 5.0%) and laparoscopic nephrectomy had the lowest risk (56/8,475; 0.7%). Most patients (58,782; 90%) were classified as high risk for VTE using the Caprini score. After adjusting for known risk factors, the risk of venous thromboembolism was significantly greater for radical cystectomy compared to laparoscopic nephrectomy (relative risk = 7.0; 95% CI: 5.0-9.2).

Conclusions: This study reports procedure-specific venous thromboembolism risk adjusting for known risk factors. These data demonstrate that procedure-specific thromboprophylaxis guidelines are needed in urology.