The Preoperative Risk Factors that Influence the Postoperative Renal Function in Living Donor Nephrectomy: The Impact of Dominant Kidney Nephrectomy / 대한비뇨기과학회지

ABSTRACT

PURPOSE: We wanted to investigate the effect of dominant kidney nephrectomy on the postoperative renal function and we wanted to determine the preoperative risk factors that influence the postoperative renal function in living donor nephrectomy. MATERIALS AND METHODS: A total of 297 living kidney donors(159 males and 138 females) who underwent nephrectomy were included in this study. Renal function was measured by the serum creatinine levels and (99m)Tc-diethylenetriamine penta-acetic acid(DTPA) renal scanning. Using univariate and multivariate analyses, the following independent variables were evaluated to predict a postoperative serum creatinine level 1.5mg/dl or higher removal of a functionally dominant kidney or a larger kidney according to the DTPA renal scan or CT, age, gender, body mass index (BMI), comorbidity, preoperative serum creatinine and the preoperative glomerular filtration rate(GFR). RESULTS: Of the 297 subjects, 134(55%) underwent donor nephrectomy on the left side, and 163(45%) underwent donor nephrectomy on the right side. Univariate analysis showed that gender and the preoperative creatinine level were significantly associated with postoperative serum creatinine elevation(1.5mg/dl or higher)(p<0.05). Multivariate analysis showed that the preoperative creatinine level(p<0.001), the preoperative GFR (p=0.015) and removal of a functionally dominant kidney(p=0.049) were significant factors. The cut-off values from the receiver operating characteristics(ROC) curves were 1.0mg/dl for the preoperative creatinine level, 90.24ml/min/1.73m2 for the preoperative GFR, and 10.94% for the difference of the relative renal function on DTPA. CONCLUSIONS: The preoperative serum creatinine level and the preoperative GFR are critical predictive factors for renal function after living donor nephrectomy. The impact of removing a functionally dominant kidney on the postoperative renal function should be cautiously interpreted in patients where the function of the nondominant kidney is favored.