Plenary: Next Frontier, Sunday, Afternoon Session
Presentation Authors: Rodney Breau, Dean Fergusson, Kristen McAlpine, Greg Knoll, Chris Morash, Luke Lavallee, Sonya Cnossen, Ranjeeta Mallick, Ottawa, Canada, Antonio Finelli, Michael Jewett, Toronto, Canada, Bradley Leibovich, Rochester, MN, Anil Kapoor, Hamilton, Canada, Frederic Pouliot, Quebec City, Canada, Jonathan Izawa, London, Canada, Ricardo Rendon, Halifax, Canada, Ilias Cagiannos*, Ottawa, Canada
Introduction: To preserve renal function, partial nephrectomy is the preferred treatment for patients with renal tumours. Renal hypothermia during partial nephrectomy has been advocated and performed by surgeons for decades to reduce ischemic damage. The purpose of this trial was to determine the effectiveness and safety of renal hypothermia during partial nephrectomy.
Methods: Patients at six academic tertiary care hospitals were randomized to renal hypothermia or no renal hypothermia during open partial nephrectomy. Broad inclusion criteria were used and patients were only excluded if they were <18 years old, were pregnant, had surgery planned for the contralateral kidney within 12 months, or had cold agglutinins. Glomerular filtration rate (GFR) was assessed by plasma clearance of 99mTc-DTPA and differential renal function by renal scintigraphy. The primary outcome was GFR at 1-year post-surgery. Secondary outcomes included kidney specific renal function (GFR x % kidney function) at 1-year post-surgery, peri-operative adverse events, and patient reported quality of life. The trial was registered with clinicaltrials.gov (NCT01529658) and was designed with 90% power to detect a difference of 10ml/min/1.73m2 at a 5% significance level.
Results: A total of 184 patients were randomized and 161 (79 hypothermia, 82 no hypothermia) were alive with primary outcome information. Hypothermia and no-hypothermia patients had similar 1-year GFR (89.0 vs 80.5 mL/min/1.73m2; mean difference 8.5, 95% CI -0.4 to 17.4). The overall decrease in GFR was -9.0 ml/min/1.73m2 in the hypothermia group compared to -8.8 mL/min/1.73m2 in the no-hypothermia group (mean difference 0.2 mL/min/1.73m2, 95% CI -5.4 to 5.7). Kidney specific decrease in GFR was also similar between groups (-7.0 vs -6.8 mL/min/1.73m2; mean difference 0.2 mL/min/1.73m2, 95% CI -3.6 to 4.0). No difference in renal function was observed when patients were stratified by median age, baseline renal function (>45 vs. <45 mL/min/1.73m2) or by duration of ischemia (<20 vs. >20 minutes, <30 vs. >30 minutes). There was no difference in surgical complications or quality of life between the groups.
Conclusions: Renal hypothermia does not improve renal function 1-year post-partial nephrectomy. These findings suggest that intraoperative hypothermia should be abandoned as a method for long-term renal function preservation. These data indirectly support the use of laparoscopic/robotic assisted partial nephrectomy where renal hypothermia is difficult to perform.
Source of Funding: Canadian Institute of Health Research