Warm Ischemia-Related Postoperative Renal Dysfunction in Elective Laparoscopic Partial Nephrectomy Recovers During...

To analyze the impact of warm ischemia time (WIT) on early postoperative and ultimate renal function after elective laparoscopic partial nephrectomy (LPN).

One hundred and twenty-seven patients who underwent elective, ischemia-applied LPN were investigated in this study. The study patients were without stage 3 or greater chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m(2)) before LPN. Initially, the patients were grouped using the criteria of postoperative de novo stage 3 or greater CKD: Group A (n=104, eGFR ≥60 mL/min/1.73 m(2)) and group B (n=23, eGFR <60 mL/min/1.73 m(2)). The patients were also divided into two groups using 27.75 minute cutoff value obtained by receiver operating curve (ROC) analysis for WIT: Group 1 (n=69, WIT <27.75 min) and group 2 (n=58, WIT ≥27.75 min). The groups were compared with regard to demographic, perioperative, histopathologic, and renal functional outcomes.

The decreased preoperative eGFR (P<0.001) and increased WIT (P=0.007), operative time (P=0.015), diabetes mellitus (DM) rate (P=0.019) and pathologic tumor size (P=0.031) were significantly different in group B. Multivariate analysis determined that independent predictors of de novo stage 3 or greater CKD in the early postoperative period were preoperative eGFR (P<0.001), WIT (P=0.014), and DM (P=0.030); meanwhile, preoperative eGFR (P=0.006) was the only independent predictor at last follow-up. Decreased median postoperative eGFR (P=0.018) and percent preserved postoperative eGFR (P=0.001) were significantly different in the increased WIT group, as well as elevated median postoperative eGFR loss (P=0.001). After similar follow-up (26 vs 23.5 months, P=0.913), the increased and limited WIT groups were not significantly different with regard to final eGFR (P=0.936), final eGFR loss (P=0.749) and percent preserved final eGFR (P=0.690).

In elective LPN, increased WIT plays an important role in renal functional loss in the early postoperative period. This functional loss, however, recovered after an intermediate term follow-up period, similar to that of patients undergoing limited WIT.