title: Retrograde renal cooling to minimize ischemia.
abstract: OBJECTIVE
  During partial nephrectomy, renal hypothermia has been shown to decrease ischemia induced renal damage which occurs from renal hilar clamping. In this study we investigate the infusion rate required to safely cool the entire renal unit in a porcine model using retrograde irrigation of iced saline via dual-lumen ureteral catheter.
  
  
  METHODS
  Renal cortical, renal medullary, bowel and rectal temperatures during retrograde cooling in a laparoscopic porcine model were monitored in six renal units. Iced normal saline was infused at 300 cc/hour, 600 cc/hour, 1000 cc/hour and gravity (800 cc/hour) for 600 seconds with and without hilar clamping.
  
  
  RESULTS
  Retrograde cooling with hilar clamping provided rapid medullary renal cooling and significant hypothermia of the medulla and cortex at infusion rates ≥ 600 cc/hour. With hilar clamping, cortical temperatures decreased at -0.90 C/min. reaching a threshold temperature of 26.90 C, and medullary temperatures decreased at -0.90 C/min. reaching a temperature of 26.10 C over 600 seconds on average for combined data at infusion rates = 600 cc/hour. The lowest renal temperatures were achieved with gravity infusion. Without renal hilum clamping, retrograde cooling was minimal at all infusion rates.
  
  
  CONCLUSIONS
  Significant renal cooling by gravity infusion of iced cold saline via a duel lumen catheter with a clamped renal hilum was achieved in a porcine model. Continuous retrograde irrigation with iced saline via a two way ureteral catheter may be an effective method to induce renal hypothermia in patients undergoing robotic assisted and/or laparoscopic partial nephrectomy.
authors.affiliation: Tulane University School of Medicine, Department of Urology, New Orleans, LA 70112, USA. jcolli.tulane@gmail.com
authors.forename: Janet L
authors.initials: JL
authors.lastname: Colli
authors.forename: Philip
authors.initials: P
authors.lastname: Dorsey
authors.forename: Leah
authors.initials: L
authors.lastname: Grossman
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Lee
mesh_terms: D000818:Animals; D003250:Constriction; D007036:Hypothermia, Induced / Q000379:methods*; D007511:Ischemia / Q000517:prevention & control*; D007668:Kidney / Q000098:blood supply* / Q000293:injuries; D023421:Models, Animal; D009392:Nephrectomy / Q000379:methods*; D012016:Reference Values; D015203:Reproducibility of Results; D012965:Sodium Chloride / Q000627:therapeutic use*; D013552:Swine; D013696:Temperature; D007507:Therapeutic Irrigation / Q000379:methods; D013997:Time Factors; D014546:Urinary Catheterization / Q000379:methods
chemical_list: D012965:Sodium Chloride