Procedure-specific Risks of Thrombosis and Bleeding in Urological Surgery: Systematic Review and Meta-analysis: Beyond the Abstract

Substantial variation exists in the use of post-surgery thromboprophylaxis in patients undergoing urological surgery, both between procedures, and between clinicians. Earlier thromboprophylaxis recommendations have not been procedure-specific. In an effort to improve the body of urology-specific evidence informing thromboprophylaxis decisions, we have conducted a series of systematic reviews addressing venous thromboembolism (VTE) and bleeding in urologic surgery: Risk of Thrombosis and Bleeding in Urological Surgery (ROTBUS). 

We have recently published ROTBUS Cancer and Non-Cancer articles in European Urology, and these are freely available at ROTBUS findings guided the development of European Association of Urology (EAU) Thromboprophylaxis in Urological Surgery guideline, which was also recently releases and is available at

In the ROTBUS project, we included observational studies of any urological surgery procedure with at least 50 adult patients. We extracted VTE events (symptomatic deep vein thrombosis and pulmonary embolism) and bleeding requiring reoperation, as well as all fatalities due to pulmonary emboli or major bleeding. For each individual procedure (including approach, eg, laparoscopic, robotic, open) we estimated the 28-day risk of thrombosis and bleeding. We also modeled the risk based on patient risk factors (older age, obesity, prior VTE, family history of VTE). This is the first attempt to estimate procedure-specific risks of thrombosis and bleeding for urology.

We found that the risk of blood clots and major bleeds differed over time.  The highest risk of bleeding occurs within a few days after surgery, while the risk of thrombosis is constant over the 4 weeks after surgery. These risks suggest that the big benefit of thromboprophylaxis (reducing blood clots risk while avoiding increase in major bleeds) occurs between one and four weeks after surgery. 

The risk of thrombosis varies greatly between procedures and within different approaches for procedures for the same disease (eg, laparoscopic vs open vs robotic prostatectomies). In cancer, some procedures, such as both open and robotic cystectomy, were high risk for VTE, while many prostatectomy procedures (for instance, robotic with no or limited PLND) were low risk for thrombosis. Overall, the quality of evidence also differed greatly according to procedure. We found the highest quality evidence in cystectomy and prostatectomy procedures, with lower quality of evidence in kidney procedures and other benign procedures such as TURP. 

For some procedures, thrombosis risk was high and bleeding risk low; in these situations, prophylaxis is warranted. In other procedures, VTE risk was low and bleeding high, and prophylaxis is clearly not recommended in these situations. In many situations, the trade-off was not so clear because of a close balance of benefit and harm, and because of uncertainty in both VTE and major bleeding estimates.

In summary, we have presented the first evidence of baseline risks of VTE and major bleeding for individual procedures in urologic surgery. Our results provide the best evidence for thromboprophylaxis management in urological surgery, and highlight areas in which additional research is most needed. 

Written by: Kari A.O. Tikkinen1, Samantha Craigie 2,3 and Gordon H. Guyatt2,4

1. Departments of Urology and Public Health, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
2. Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
3. Michael G. DeGroote National Pain Centre, McMaster University, Hamilton, ON, Canada; d Sc
4. Department of Medicine, McMaster University, Hamilton, ON, Canada 

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