title: Acute kidney injury after on-pump or off-pump coronary artery bypass grafting in elderly patients.
abstract: BACKGROUND
  An exploratory analysis of the German Off Pump Coronary Artery Bypass Grafting in Elderly Patients (GOPCABE) trial was performed to investigate the effect of off-pump coronary artery bypass grafting (CABG) on kidney function after the operation.
  
  
  METHODS
  Data on kidney function were available from 1,612 patients, representing 67% of the study population. Preoperative kidney function was graded according to the glomerular filtration rate. Acute kidney injury (AKI) within the first week after the operation was defined and classified according to the Acute Kidney Injury Network (AKIN) criteria. The incidence and severity of AKI was compared between patients operated on on-pump or off-pump.
  
  
  RESULTS
  Impaired kidney function was seen in 642 patients (40%), and 19 patients had preexisting end-stage kidney disease. AKI of any severity occurred in half of all patients undergoing CABG, with AKIN stage 1 accounting for most of the cases. The incidence and severity of AKI in patients undergoing on-pump vs off-pump CABG was AKIN stage 1: 298 (37%) vs 329 (42%); AKIN stage 2: 38 (5%) vs 43 (5%); and AKIN stage 3: 44 (6%) vs 44 (6%), which did not differ significantly (p=0.174). New renal replacement therapy was necessary in 3.2% (on-pump) and in 2.7% (off-pump) of all patients. Stratification according to preoperative kidney function yielded comparable frequencies of AKI for on-pump and off-pump CABG.
  
  
  CONCLUSIONS
  AKI was common in elderly patients undergoing CABG, but deterioration of kidney function requiring renal replacement therapy was a rare event. Off-pump CABG was not associated with decreased rates or reduced severity of AKI in elderly patients.
authors.affiliation: Cardiovascular Clinic Bad Neustadt, Bad Neustadt, Germany. Electronic address: wilko.reents@herzchirurgie.de.
authors.forename: Wilko
authors.initials: W
authors.lastname: Reents
authors.affiliation: Department of Cardiothoracic Surgery, University Medical Center, Regensburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Hilker
authors.affiliation: Clinic for Heart, Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Börgermann
authors.affiliation: Department of Cardiac and Vascular Surgery, Robert Bosch Hospital, Stuttgart, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Albert
authors.affiliation: Department of Cardiac Surgery, University Heart Center Dresden, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Plötze
authors.affiliation: Cardiovascular Clinic Bad Neustadt, Bad Neustadt, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Zacher
authors.affiliation: Cardiovascular Clinic Bad Neustadt, Bad Neustadt, Germany.
authors.forename: Anno
authors.initials: A
authors.lastname: Diegeler
authors.affiliation: Department of Cardiovascular Surgery, Justus-Liebig University Gießen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Böning
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D000368:Aged; D000369:Aged, 80 and over; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects; D003324:Coronary Artery Disease / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D008297:Male; D011183:Postoperative Complications; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome