title: Poorly functioning kidneys recover from ischemia after partial nephrectomy as well as strongly functioning kidneys.
abstract: OBJECTIVE
  Poorly functioning kidneys may not recover from ischemia as well as strongly functioning kidneys. This could impact surgical approaches to partial nephrectomy.
  
  
  METHODS
  We analyzed the records of 155 consecutive patients treated with partial nephrectomy who underwent appropriate studies to facilitate analysis of function and parenchymal mass in the operated kidney, including computerized tomography and glomerular filtration rate measurement within 2 months preoperatively and 4 to 12 months postoperatively. Patients with a contralateral kidney also underwent renal scan in the same time frame to provide split renal function. Computerized tomography was done to measure functional parenchymal volume before and after partial nephrectomy. Recovery from ischemia, defined as percent glomerular filtration rate saved/percent volume saved, was considered 100% if all nephrons recovered from the ischemic insult.
  
  
  RESULTS
  The median R.E.N.A.L. nephrotomy score was 8. Cold ischemia was used in 64 patients and limited warm ischemia was used in 91 (median 27 and 20 minutes, respectively). The median percent glomerular filtration rate saved in the operated kidney was 80% and the median parenchymal volume saved was 83%. The overall median rate of recovery from ischemia was 95%, including 100% for cold ischemia and 92% for limited warm ischemia. Recovery from ischemia was approximately 100% and was similar for all strata of preoperative estimated glomerular filtration rates in the operated kidney (p = 0.24), even in the warm ischemia subgroup.
  
  
  CONCLUSIONS
  Our results suggest that the quantity of parenchyma preserved is the main determinant of the postoperative glomerular filtration rate after partial nephrectomy as long as limited warm ischemia or hypothermia is used. Even poorly functioning kidneys recover well from the ischemic insult proportionate to the amount of parenchyma preserved.
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Mir
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Toshio
authors.initials: T
authors.lastname: Takagi
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Campbell
authors.affiliation: Imaging Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Sharma
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio; Imaging Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Erick M
authors.initials: EM
authors.lastname: Remer
authors.affiliation: Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Li
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Sevag
authors.initials: S
authors.lastname: Demirjian
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Robert
authors.initials: R
authors.lastname: Stein
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Jihad
authors.initials: J
authors.lastname: Kaouk
authors.affiliation: Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio. Electronic address: Campbes3@ccf.org.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Campbell
mesh_terms: D000368:Aged; D050377:Cold Ischemia; D005260:Female; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods; D020127:Recovery of Function; D012189:Retrospective Studies; D052096:Warm Ischemia
keywords: chronic; ischemia; kidney; nephrectomy; recovery of function; renal insufficiency