Prophylaxis Fails to Prevent Thromboembolism After Partial Nephrectomy

December 21, 2015
Leah Lawrence

Administering pharmacological prophylaxis against venous thromboembolism (VTE) did not decrease the occurrence of VTE in patients treated with robotic partial nephrectomy, and it did not increase the rate of hemorrhagic events.

Administering pharmacological prophylaxis against venous thromboembolism (VTE) did not decrease the occurrence of VTE in patients treated with robotic partial nephrectomy, and it did not increase the rate of hemorrhagic events, according to the results of a single-center study published recently in the Journal of Urology.

“The majority of VTE events occurred after hospital discharge but within the first 30 days post surgery,” researcher Onder Kara, of Glickman Urological and Kidney Institute at Cleveland Clinic, and colleagues wrote. “Longer duration of the pharmacological prophylaxis for the prevention of VTE after robotic partial nephrectomy should be considered.”

According to the study, the American College of Chest Physicians currently recommends the use of pharmacological prophylaxis in patients undergoing radical nephrectomy for cancer; however, this prophylaxis is not as commonly used after partial nephrectomy because of the risks associated with bleeding.

With this single-center study, Kara and colleagues wanted to evaluate the safety and efficacy of VTE prophylaxis in patients undergoing partial nephrectomy. They retrospectively examined a group of patients who had robotic partial nephrectomy performed between 2006 and 2014. The database produced information on 222 patients who underwent prophylaxis and 762 who did not.

The institution’s VTE pharmacological prophylaxis protocol includes use of unfractionated heparin or low molecular weight heparin.

Outcomes for mean operation time, median warm ischemia time, and estimated blood loss were similar between patients regardless of prophylaxis. VTE occurred in 1.8% of patients with prophylaxis and 2.1% of those without.

Patients administered VTE prophylaxis had higher rates of overall (33.7% vs 24%) and major postoperative (9.9% vs 4.9%) complications compared to patients without prophylaxis. However, the rate of adverse hemorrhagic events and VTE events were not significantly different between the two groups.

A multivariable analysis found that surgeries performed by fellowship-trained surgeons had lower odds for intraoperative complication (odds ratio [OR], 0.45; P = .03).

The majority (90%) of VTE events occurred within the first month of surgery. Postoperative complications were significantly associated with the occurrence of postoperative VTE (OR, 15.00; P < .0001).

“Recent data suggests that in patients undergoing oncological surgery the incidence of VTE within 1 month after the procedure is between 30.6% and 37.8%,” the researchers wrote. “Several randomized studies have demonstrated reduction in VTE events in patients with longer duration of prophylaxis after oncological surgeries. The timing of VTE events might be an explanation for the apparent lack of benefit of pharmacological prophylaxis in patients receiving it as pharmacological prophylaxis administration was only limited to the duration of hospital admission and was discontinued at the time of discharge.”