title: Acute Ipsilateral Renal Dysfunction after Partial Nephrectomy in Patients with a Contralateral Kidney: Spectrum Score to Unmask Ischemic Injury.
abstract: Acute ischemic injury in the operated kidney after partial nephrectomy (PN) is often masked by a functional contralateral kidney; however, there is no practical method to assess this and its prognostic significance has not been defined.
  
  
  
  We propose a spectrum score to reflect the degree of ischemic insult in the ipsilateral kidney and study its relationship to subsequent functional recovery.
  
  
  
  From 2007 to 2014, 243 patients with a functional contralateral kidney underwent PN with necessary studies for detailed analysis of function and parenchymal mass before and after surgery in the ipsilateral kidney. Based on split function and percent parenchymal mass preserved in the ipsilateral kidney, we determined: serum creatinine (SCr)ideal-peak: expected peak SCr presuming no ischemic injury; and SCrworstcase-peak: expected peak SCr presuming temporary complete nonfunction of the ipsilateral kidney. The acute ipsilateral renal dysfunction spectrum score was defined: (observed peak SCr - SCrideal-peak)/(SCrworstcase-peak- SCrideal-peak). Subsequent functional recovery was defined: (percent function preserved)/(percent mass saved).
  
  
  
  PN.
  
  
  
  Factors associated with spectrum score and relationship between spectrum score and subsequent functional recovery were evaluated by linear regression.
  
  
  
  Median duration of warm ischemia (n=152) was 21min (interquartile range [IQR] = 15-27) and hypothermia (n=91) 26min (IQR=23-30). Median parenchymal mass preservation was 83% (IQR=74-91%). Warm ischemia and longer ischemia duration associated with higher spectrum score (both p<0.05). Increased spectrum score (<25%, 25-50%, 50-75%, and >75% quartiles) had decreased functional recovery (98%, 94%, 90%, and 89%, respectively, p<0.001). However, this trend was not observed in the hypothermia cohort. On multivariable analysis spectrum score and ischemia type significantly associated with functional recovery (both p<0.01), while age and comorbidities failed to associate (p=0.3-0.7).
  
  
  
  Acute ipsilateral renal dysfunction spectrum score unmasks the degree of ischemic insult in the operated kidney after PN and associates with functional recovery. While increased spectrum score associates with suboptimal recovery, even patients with a high spectrum score reached 89-90% recovery.
  
  
  
  Acute functional decline after partial nephrectomy is difficult to evaluate in patients with two kidneys, but a proposed spectrum score can be used to evaluate this. Increased spectrum score reflects increased ischemia and may impact the functional recovery of the kidney.
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Urology Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
authors.forename: Zhiling
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Department of Urology, Shanghai, China.
authors.forename: Juping
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Urology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Dong
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Diego
authors.initials: D
authors.lastname: Aguilar Palacios
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Imaging Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Erick M
authors.initials: EM
authors.lastname: Remer
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Li
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Sevag
authors.initials: S
authors.lastname: Demirjian
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Zabell
authors.affiliation: Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address: Campbes3@ccf.org.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Campbell
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology* / Q000503:physiopathology*; D000368:Aged; D050377:Cold Ischemia / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced; D007668:Kidney / Q000503:physiopathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000009:adverse effects* / Q000379:methods; D059351:Organ Sparing Treatments; D020127:Recovery of Function; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D052096:Warm Ischemia / Q000009:adverse effects*
chemical_list: D003404:Creatinine
keywords: Acute kidney injury; Functional recovery; Ischemia; Parenchymal mass reduction; Partial nephrectomy