Abstract
Aim: The growth in the incidence of small renal masses has led the implementation of laparoscopic partial nephrectomy to become the technique of choice. However, arterial clamping and secondary renal ischemia still mean a controversial issue due to the risk of renal failure. Our objective is to evaluate the existing literature and its relationship to our experience.
Methods: We performed a retrospective study of our series over six years. We analyzed different clinical, perioperative and postoperative functional outcome variables and compared the relationship between tumor complexity and the need for ischemia as well as the relation between ischemia time and renal function over a follow-up time of 6 months. For the discussion, we led a review of the literature on the subject and the paradigm shift that has taken place over the years.
Results: A total of 148 patients, most of them male (68.2%) with an average age of 62.4 [standard deviation (SD) 1.7] years, had a Charlson index of 3 [interquartile range (IQR) 1-4]. The average R.E.N.A.L. score was 6 (IQR 5-8). Intraoperative complications were observed in 8.1% of the cases, most of which involved bleeding from a major artery or vein (7.4%). Postoperative complications occurred in 23.6% of the patients, the majority being classified as Clavien 2. Arterial clamping was carried out in 52.7% of the interventions, with a median ischemia time of 8 min (IQR 0-18). The average hospital stay was three days (IQR 2-5). Previous median glomerular filtration rate (GFR) was 83 mL/min/1.73 m2 (IQR 66.2-93.6). On the first postoperative day, the median GFR was 78.4 (SD 21.8), and at 6 months, it was 75.2 (SD 22). We found no statistically significant differences between having hypertension or diabetes mellitus and GFR after surgery, but we found differences in the correlation of a Charlson index ≥ 3 and deterioration of renal function, being the P values 0.01, 0.08 and 0.00 for the first postoperative day, after three and 6 months, respectively. No statistically significant differences were found in whether having a previous chronic kidney disease influenced the decision to perform arterial clamping or not, with a P value of 0.104. Statistically significant differences were found in the relationship between R.E.N.A.L. score and ischemia time.
Conclusion: Renal tumors with a higher R.E.N.A.L. score involve the need to accomplish a longer arterial clamping, but its relationship with the deterioration of renal function is unclear, since there are other risk factors, such as patient’s comorbidities.