Development of a risk scoring system for predicting acute kidney injury after minimally invasive partial and radical nephrectomy: a retrospective study.

backgroundAcute kidney injury after partial or radical nephrectomy remains an unsolved problem even when using minimally invasive techniques. We aimed to identify risk factors for acute kidney injury (AKI) after minimally invasive nephrectomy and to develop a clinical risk scoring system.

methodsMedical records of 1762 patients who underwent minimally invasive laparoscopic or robot-assisted laparoscopic partial (n = 1009) or radical (n = 753) nephrectomy from December 2005 to November 2018 were reviewed. Candidate risk factors were screened using univariate analysis and ranked using linear discriminant analysis; top ranking factors were incorporated into a multivariate logistic regression model. Then, the final clinical scoring system was created based on the estimated odds ratios.

resultsThe incidence of acute kidney injury after partial or radical nephrectomy was 20.3 and 61.6%, respectively. Risk factors incorporated into the scoring system included: size of the parenchymal mass removed (3 < parenchymal mass ≤ 4 cm, 1 point; 4 < parenchymal mass ≤ 6 cm, 3 points; parenchymal mass > 6 cm, 5 points), male sex (2 points), diabetes mellitus (1 point), warm ischemia time ≥ 25 min (1 point), and immediate postoperative neutrophil count ≥ 12,000 µl

conclusionOur risk scoring system could help clinicians identify those at risk of acute kidney injury after minimally invasive partial or radical nephrectomy, thereby optimizing postoperative management.