title: Preoperative hypoalbuminemia is a major risk factor for acute kidney injury following off-pump coronary artery bypass surgery.
abstract: OBJECTIVE
  To investigate the association between preoperative low serum albumin level and acute kidney injury (AKI) after off-pump coronary artery bypass surgery (OPCAB) METHOD: We assessed preoperative and perioperative risk factors, and preoperative serum albumin concentration in 1,182 consecutive adult patients with preoperative normal renal function who underwent OPCAB surgery. Each patient was categorized by maximal Acute Kidney Injury Network (AKIN) criteria based on creatinine changes within the first 48 h after OPCAB. Logistic regression and propensity analyses were performed to evaluate the association between preoperative low serum albumin level and postoperative AKI.
  
  
  RESULTS
  Of the 1,182 patients, 334 (28.3%) developed AKI. Risk factors for AKI were old age, diabetes mellitus, maximal cardiovascular component of the sequential organ failure assessment score, perioperative transfusion, and postoperative C-reactive protein concentration. The risk of AKI was negatively correlated with the volume of crystalloid infused during surgery. A preoperative serum albumin level of <4.0 g/dl was independently associated Ith postoperative AKI [multivariable logistic analysis: odds ratio (OR) 1.83, 95 % confidence interval (CI) 1.27-2.64; P = 0.001; propensity analysis: OR 1.62, 95 % CI 1.12-2.35; P = 0.011). AKI was associated with prolonged stay in the intensive care unit and hospital and a high mortality rate.
  
  
  CONCLUSIONS
  Preoperative low serum albumin level is an independent risk factor for AKI, and postoperative AKI is associated with poor outcomes after OPCAB in patients with preoperative normal renal function.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Pungnap 2-dong, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Eun-Ho
authors.initials: EH
authors.lastname: Lee
authors.forename: Seung-Hee
authors.initials: SH
authors.lastname: Baek
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Chin
authors.forename: Dae-Kee
authors.initials: DK
authors.lastname: Choi
authors.forename: Hyo-Jung
authors.initials: HJ
authors.lastname: Son
authors.forename: Wook-Jong
authors.initials: WJ
authors.lastname: Kim
authors.forename: Kyung-Don
authors.initials: KD
authors.lastname: Hahm
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Sim
authors.forename: In-Cheol
authors.initials: IC
authors.lastname: Choi
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis* / Q000453:epidemiology / Q000401:mortality; D000368:Aged; D000418:Albumins / Q000032:analysis*; D016001:Confidence Intervals; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects*; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D034141:Hypoalbuminemia / Q000175:diagnosis* / Q000473:pathology; D007723:Korea; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011300:Preoperative Care / Q000379:methods*; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000418:Albumins