Risk Factors for Postoperative Hemorrhage After Partial Nephrectomy

PURPOSE: To evaluate the frequency and clinical characteristics of postoperative hemorrhage as a complication of partial nephrectomy. MATERIALS AND METHODS: The demographics, physical statistics, tumor size, R.E.N.A.L. nephrometry score, operative method, warm ischemic time, and presence of postoperative hemorrhage and its severity and method of intervention were examined in 300 partial nephrectomy patients in two medical centers (Stanford Medical Center and Kyung Hee University Medical Center) between March 2000 and March 2012. RESULTS: Of the 300 subjects, 13 (4.3%) experienced postoperative hemorrhage severe enough to require intervention more invasive than transfusion (Clavien grade III or higher). Univariate analysis of the bleeding and nonbleeding groups showed that whereas age, ischemic time, tumor size and stage, body mass index, American Society of Anesthesiologists class, and operative method did not differ significantly, the exophyticity (E) score was significantly higher for severe postoperative hemorrhage (p=0.04). However, multivariate analysis showed none of the factors to differ significantly. In most of the cases requiring intervention, selective embolization was sufficient, but in one case explorative laparotomy and nephrectomy were required. Clinical characteristics varied significantly among severe hemorrhage cases, with time of onset ranging from the first to the 30th postoperative day and symptoms presenting in a diverse manner, such as gross hematuria and pleuritic chest pain. Computed tomography and angiographic findings were consistent with either arteriovenous fistula or pseudoaneurysms. CONCLUSIONS: Severe hemorrhage after partial nephrectomy is rare. Nonetheless, with the great variability in presenting symptoms and time of onset after surgery, surgeons should exercise great vigilance during the postoperative care of partial nephrectomy patients.