title: Impact of the time of coronary angiography on acute kidney injury after elective off-pump coronary artery bypass surgery.
abstract: BACKGROUND
  Previous studies have suggested that early surgery after coronary angiography may be associated with the risk of acute kidney injury (AKI) in cardiac surgery with cardiopulmonary bypass. However, the effect of coronary angiography on the risk of AKI after off-pump coronary artery bypass graft surgery (OPCABG) remains uncertain.
  
  
  METHODS
  We assessed preoperative and perioperative data in 1,364 consecutive adult patients who underwent elective OPCABG surgery after coronary angiography. Acute kidney injury was defined by Acute Kidney Injury Network criteria based on changes in serum creatinine within the first 48 hours after OPCABG. Multivariable logistic regression was performed to evaluate the association of the time interval between coronary angiography and OPCABG with postoperative AKI.
  
  
  RESULTS
  Acute kidney injury occurred in 391 patients (28.7%). The unadjusted and adjusted rates of AKI according to the length of time between coronary angiogram and OPCABG did not show any increasing or decreasing trend (p = 0.86 and p = 0.33 for trends of unadjusted and adjusted AKI rates, respectively), and early OPCABG after coronary angiography was not related to postoperative AKI. Results were the same in high-risk patients with preoperative renal insufficiency, low ejection fraction, or who received an ionic contrast agent or a high dose of contrast agent.
  
  
  CONCLUSIONS
  The risk of postoperative AKI was not related to the time between coronary angiography and OPCABG. These findings suggest that delaying elective OPCABG after coronary angiography owing to the sole concern for renal function may be unnecessary.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Eun-Ho
authors.initials: EH
authors.lastname: Lee
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Chin
authors.forename: Kyoung-Woon
authors.initials: KW
authors.lastname: Joung
authors.forename: Dae-Kee
authors.initials: DK
authors.lastname: Choi
authors.forename: Wook-Jong
authors.initials: WJ
authors.lastname: Kim
authors.forename: Jung-Bok
authors.initials: JB
authors.lastname: Lee
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 / Q000453:epidemiology / Q000209:etiology*; D017023:Coronary Angiography / Q000379:methods; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects*; D017558:Elective Surgical Procedures; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D018570:Risk Assessment; D013997:Time Factors
keywords: 23