title: Pre-procedural bioimpedance vectorial analysis of fluid status and prediction of contrast-induced acute kidney injury.
abstract: OBJECTIVE
  The aim of this study was to evaluate the relationship between pre-procedural fluid status assessed by bioimpedance vector analysis (BIVA) and development of contrast-induced acute kidney injury (CI-AKI).
  
  
  BACKGROUND
  Accurate fluid management in patients undergoing angiographic procedures is of critical importance in limiting the risk of CI-AKI. Therefore, establishing peri-procedural fluid volume related to increased risk of CI-AKI development is essential.
  
  
  METHODS
  We evaluated the fluid status by BIVA of 900 consecutive patients with stable coronary artery disease (CAD) immediately before coronary angiography, measuring the resistance/height (R/H) ratio and impedance/height (Z/H) vector. CI-AKI was defined as an increase in serum creatinine ≥0.5 mg/dl above baseline within 3 days after contrast administration (iodixanol).
  
  
  RESULTS
  CI-AKI occurred in 54 patients (6.0%). Pre-procedural R/H ratios were significantly higher in patients with CI-AKI than without CI-AKI (395 ± 71 Ohm/m vs. 352 ± 58 Ohm/m, p = 0.001 for women; 303 ± 59 Ohm/m vs. 279 ± 45 Ohm/m, p = 0.009 for men), indicating lower fluid volume in the patients with CI-AKI. When patients were stratified according to R/H ratio, there was an almost 3-fold higher risk in patients with higher values (odds ratio [OR]: 2.9; 95% confidence interval [CI]: 1.5 to 5.5; p = 0.002). The optimal receiver-operating characteristic curve analysis threshold values of R/H ratio for predicting CI-AKI were 380 Ohm/m for women and 315 Ohm/m for men. R/H ratio above these thresholds was found to be a significant and independent predictor of CI-AKI (OR: 3.1; 95% CI: 1.8 to 5.5; p = 0.001).
  
  
  CONCLUSIONS
  Lower fluid status evaluated by BIVA immediately before contrast medium administration resulted in a significant and independent predictor of CI-AKI in patients with stable CAD. This simple noninvasive analysis should be tested in guiding tailored volume repletion.
authors: Division of Cardiology, New Prato Hospital, Prato, Italy. Electronic address: mauromaioli1956@gmail.com.
authors: Mauro
authors: M
authors: Maioli
authors: Division of Cardiology, New Prato Hospital, Prato, Italy.
authors: Anna
authors: A
authors: Toso
authors: Division of Cardiology, New Prato Hospital, Prato, Italy.
authors: Mario
authors: M
authors: Leoncini
authors: Division of Cardiology, New Prato Hospital, Prato, Italy.
authors: Nicola
authors: N
authors: Musilli
authors: Division of Cardiology, New Prato Hospital, Prato, Italy.
authors: Francesco
authors: F
authors: Bellandi
authors: Division of Nephrology, University of Virginia Health System, Charlottesville, Virginia.
authors: Mitchell H
authors: MH
authors: Rosner
authors: Baylor Healthcare System, Baylor Heart and Vascular Institute, Baylor Jack and Jane Hamilton Heart and Vascular Hospital, Baylor University Medical Center, Dallas, Texas; Heart Hospital, Plano, Texas.
authors: Peter A
authors: PA
authors: McCullough
authors: Department of Nephrology, International Renal Research Institute, St. Bortolo Hospital, Vicenza, Italy.
authors: Claudio
authors: C
authors: Ronco
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000175:diagnosis / Q000517:prevention & control; D000368:Aged; D015331:Cohort Studies; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography / Q000009:adverse effects* / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000000981:diagnostic imaging*; D017097:Electric Impedance; D005260:Female; D006801:Humans; D057446:Hydrodynamics; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D014283:Triiodobenzoic Acids / Q000009:adverse effects; D014883:Water-Electrolyte Imbalance / Q000139:chemically induced / Q000175:diagnosis*
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C044834:iodixanol
keywords: angiography; contrast media; contrast-induced nephropathy; renal insufficiency