title: Renal recovery and long-term survival following acute kidney injury after coronary artery surgery: a nationwide study.
abstract: BACKGROUND
  Acute kidney injury (AKI) is a relatively common complication following CABG and is associated with adverse outcomes. Nonetheless, we hypothesized that the majority of patients make a good long-term recovery of their renal function. We studied the incidence and risk factors of AKI together with renal recovery and long-term survival in patients who developed AKI following CABG.
  
  
  METHODS
  This nationwide study examined AKI among 1754 consecutive patients undergoing CABG in 2001-2013. AKI was defined according to the KDIGO criteria.
  
  
  RESULTS
  Postoperatively 184 (11%) patients developed AKI; 121 (7%), 27 (2%), and 36 (2%) at stages 1, 2, and 3, respectively. AKI was an independent risk factor for chronic kidney disease (CKD) and AKI patients had worse post-operative outcomes. Lower pre-operative glomerular filtration rate, higher EuroSCORE and BMI, diabetes, reoperation, and units of red blood cells transfused were independent risk factors of AKI. At post-operative day 10, renal recovery rates, defined as serum creatinine ratio <1.25 of baseline, were 96 (95% CI 91-99%), 78 (95% CI 53-90%), and 94% (95% CI 77-98%) for AKI stages 1, 2, and 3, respectively. Long-term survival was predicted by AKI with 10-year survival of patients without AKI being 76% and those with AKI stages 1, 2, and 3 being 63%, 56%, and 49%, respectively (P < 0.001).
  
  
  CONCLUSIONS
  Depending on the severity of the initial AKI, 78-97% of patients made good recovery of their kidney function. However, AKI was significantly linked to progression to CKD and long-term survival remained markedly affected by the severity of the initial kidney injury.
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: S
authors.initials: S
authors.lastname: Helgadottir
authors.affiliation: Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: M I
authors.initials: MI
authors.lastname: Sigurdsson
authors.affiliation: Faculty of Medicine, University of Iceland, Reykjavik, Iceland.|Department of Nephrology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: R
authors.initials: R
authors.lastname: Palsson
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: D
authors.initials: D
authors.lastname: Helgason
authors.affiliation: Faculty of Medicine, University of Iceland, Reykjavik, Iceland.|Department of Anesthesia and Intensive Care Medicine, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: G H
authors.initials: GH
authors.lastname: Sigurdsson
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland.|Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
authors.forename: T
authors.initials: T
authors.lastname: Gudbjartsson
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology / Q000401:mortality* / Q000503:physiopathology; D000368:Aged; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000401:mortality*; D020127:Recovery of Function; D012189:Retrospective Studies; D012307:Risk Factors