A Simple, Effective Method to Create Laparoscopic Renal Protective Hypothermia With Cold Saline Surface Irrigation: Clinical Application and Assessment

Abstract

We previously described the use of cold saline surface irrigation to achieve protective renal hypothermia in a laparoscopic partial nephrectomy porcine model. We now present our clinical application of this technique and characterization of the hypothermic effect during laparoscopic partial nephrectomy. Seven patients underwent elective laparoscopic partial nephrectomy augmented with our hypothermia technique. Parenchymal temperature sensors were placed to confirm cooling efficacy and efficiency. After transperitoneal exposure of the kidney we performed temporary hilar vascular occlusion. Surface cooling with almost freezing normal saline was delivered with a laparoscopic suction/irrigation device. Tumor laparoscopic resection and renal reconstruction were completed. Outcome measures included intraoperative changes with hypothermia and postoperative estimated glomerular filtration rate changes. All patients successfully underwent laparoscopic partial nephrectomy without complications or evidence of residual disease. A protective renal parenchymal temperature of less than 20C was achieved at a mean application time of 8.3 minutes. The hypothermic window of 15C to 25C was maintained an average of 30.4 minutes. In 2 cases cooling was repeated and 4 minutes were required to lower the temperature below 20C. The overall mean core body temperature decrease was 1.28C. At a mean followup of 22.4 months the median preoperative, immediate postoperative and final estimated glomerular filtration rate was 75, 65 and 71 ml/minute/1.73 m(2), respectively. There was no evidence of disease recurrence on followup imaging. Our technique involving cold saline surface irrigation to achieve protective renal hypothermia is reproducible, and uses readily available laparoscopic instruments and equipment. This technique can be done simply and effectively, and may expand the use of laparoscopic partial nephrectomy.