title: The effect of cardiac angiography timing, contrast media dose, and preoperative renal function on acute renal failure after coronary artery bypass grafting.
abstract: OBJECTIVE
  Our objective was to assess the effect of the timing of cardiac angiography, contrast media dose, and preoperative renal function on the prevalence of acute renal failure after cardiac surgery.
  
  
  METHODS
  Data on 395 consecutive patients who underwent coronary artery bypass grafting were prospectively collected. Creatinine clearance was estimated by the Cockcroft-Gault equation. Patients were divided into 3 groups according to the time between cardiac angiography and surgery (group A, < or = 1 day; group B, > 1 day and < or = 5 days; group C, > 5 days). Patients who underwent a salvage operation or were receiving dialysis before surgery were excluded. Acute renal failure was defined as 25% decrease from baseline of estimated creatinine clearance and estimated creatinine clearance of 60 mL/min or less on postoperative day 3. Owing to differences in preoperative characteristics between groups, propensity score analysis was used to adjust those differences.
  
  
  RESULTS
  Acute renal failure developed in 13.6% of patients. Hospital mortality was 3.3% and was higher in patients in whom acute renal failure developed (22%) versus those in whom it did not (0.3%; P < .001). Multivariable analysis identified preoperative estimated creatinine clearance of 60 mL/min or less (odds ratio [OR], 7.1), operation within 24 hours of catheterization (OR = 3.7), use of more than 1.4 mL/kg of contrast media (OR = 3.4), lower hemoglobin level (OR = 1.3), older age (OR = 1.1), and lower weight (OR = 0.95) as independent predictors of postoperative acute renal failure. Analysis of interaction between contrast dose and time of surgery revealed that high contrast dose (>1.4 mL/kg) predicted acute renal failure if surgery was performed up to 5 days after angiography.
  
  
  CONCLUSIONS
  Whenever possible, coronary bypass grafting should be delayed for at least 5 days in patients who received a high contrast dose, especially if they also have preoperative reduced renal function.
authors.affiliation: Department of Cardiothoracic Surgery, Rabin Medical Center, Beilinson Campus, Petach Tiqva 49100, Israel. Affiliated with Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. benjamin2@clalit.org.il
authors.forename: Benjamin
authors.initials: B
authors.lastname: Medalion
authors.forename: Hilit
authors.initials: H
authors.lastname: Cohen
authors.forename: Abid
authors.initials: A
authors.lastname: Assali
authors.forename: Hana
authors.initials: H
authors.lastname: Vaknin Assa
authors.forename: Ariel
authors.initials: A
authors.lastname: Farkash
authors.forename: Eitan
authors.initials: E
authors.lastname: Snir
authors.forename: Erez
authors.initials: E
authors.lastname: Sharoni
authors.forename: Philip
authors.initials: P
authors.lastname: Biderman
authors.forename: Gai
authors.initials: G
authors.lastname: Milo
authors.forename: Alexander
authors.initials: A
authors.lastname: Battler
authors.forename: Ran
authors.initials: R
authors.lastname: Kornowski
authors.forename: Eyal
authors.initials: E
authors.lastname: Porat
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000453:epidemiology*; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage* / Q000009:adverse effects*; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D005260:Female; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D011300:Preoperative Care; D015995:Prevalence; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D003287:Contrast Media