title: Prevention of Contrast-induced Nephropathy With Oxygen Supplementation: a Randomized Controlled Trial.
abstract: BACKGROUND
  The aim of the study was to investigate the efficacy of nasal oxygen as a supplementation to hydration therapy in reducing the risk of developing contrast-induced nephropathy (CIN).
  
  
  METHODS
  In a randomized controlled trial, 348 patients scheduled to undergo elective coronary angiography were randomly allocated to standard hydration plus 2 L/min to 3 L/min nasal oxygen (from 10 minutes before the procedure until the end of the procedure) (n = 176) or standard hydration alone (n = 176). The primary outcome measure was development of CIN defined as either an increase of 25% or more in serum creatinine concentrations or an increment of at least 0.5 mg/dL in serum creatinine concentrations 48 hours after catheterization.
  
  
  RESULTS
  Of the 348 patients who completed the study, 105 developed CIN (30.2%; 95% confidence interval, 25.4% to 35.0%). A diagnosis of CIN was made in 32 (18.6%) and 73 (41.5%) patients in the nasal oxygen and control arms, respectively (P < .001). In the intervention arm, creatinine concentrations postcontrast remained relatively constant (average change, 2.7%), whereas a significant increase of 17.3% was recorded in the control arm (P < .001; effect size, 11.8%).
  
  
  CONCLUSIONS
  Supplementation with nasal oxygen in addition to standard hydration appears to be an effective strategy in reducing CIN. The effect size for this intervention seems to be moderate.
authors.forename: Farzanehsadat
authors.initials: F
authors.lastname: Minoo
authors.forename: Mahboob
authors.initials: M
authors.lastname: Lessan-Pezeshki
authors.forename: Ata
authors.initials: A
authors.lastname: Firouzi
authors.forename: Salman
authors.initials: S
authors.lastname: Nikfarjam
authors.forename: Seyed Mansoor
authors.initials: SM
authors.lastname: Gatmiri
authors.affiliation: Organ Transplantation Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran. rz.elham58@gmail.com.
authors.forename: Elham
authors.initials: E
authors.lastname: Ramezanzade
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control*; D000368:Aged; D017130:Angioplasty / Q000379:methods; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography / Q000379:methods; D003404:Creatinine / Q000097:blood; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D003404:Creatinine