Oliguric acute kidney injury after microwave ablation of large liver tumors: incidence and preventive measures.

PURPOSE: Acute kidney injury (AKI), especially oliguric AKI, is a recognized complication following microwave ablation (MWA) of large liver tumors. This study evaluated the clinical features, mechanisms, risk factors and prevention strategies for oliguric AKI after MWA of large liver tumors.

METHODS: From March 2011 to May 2015, 441 patients with liver tumors ≧5 cm received MWA in our hospital. The clinical features, prevention strategies, further mechanisms and possible risk factors for oliguric AKI after MWA were analyzed.

RESULTS: One hundred four (23.6%) patients had AKI after MWA; 11 (10.6%) patients had oliguric AKI, and 93 (89.4%) patients had nonoliguric AKI. All patients with nonoliguric AKI recovered without any special treatments. The eleven patients with oliguric AKI received appropriate treatments and had completely normal renal function three months later. Using double needles for ablation was a risk factor for nonoliguric AKI, while high preoperative levels of red blood cells (RBC), hemoglobin (HGB) and albumin (Alb) were risk factors for oliguric AKI. The decrease levels of hemoglobin were significantly high in oliguric AKI patients (p < .05). Patients with oliguric AKI had abnormally high postoperative transaminase and renal function indicators. Compared to postoperative prevention, intraoperative prevention significantly lowered the occurrence of oliguric AKI (0% vs. 3.7%, p = .018) and shortened the hospital stay.

CONCLUSIONS: Patients who underwent MWA for large liver tumors are prone to develop oliguric AKI. Implementation of intraoperative strategies during MWA can effectively prevent the occurrence of this severe complication.