Prophylactic hydration to protect renal function from intravascular iodinated contrast material in patients at high risk of contrast-induced nephropathy (AMACING): a prospective, randomised, phase 3, controlled, open-label, non-inferiority trial

Lancet. 2017 Apr 1;389(10076):1312-1322. doi: 10.1016/S0140-6736(17)30057-0. Epub 2017 Feb 21.


Background: Intravenous saline is recommended in clinical practice guidelines as the cornerstone for preventing contrast-induced nephropathy in patients with compromised renal function. However, clinical-effectiveness and cost-effectiveness of this prophylactic hydration treatment in protecting renal function has not been adequately studied in the population targeted by the guidelines, against a group receiving no prophylaxis. This was the aim of the AMACING trial.

Methods: AMACING is a prospective, randomised, phase 3, parallel-group, open-label, non-inferiority trial of patients at risk of contrast-induced nephropathy according to current guidelines. High-risk patients (with an estimated glomerular filtration rate [eGFR] of 30-59 mL per min/1·73 m2) aged 18 years and older, undergoing an elective procedure requiring iodinated contrast material administration at Maastricht University Medical Centre, the Netherlands, were randomly assigned (1:1) to receive intravenous 0·9% NaCl or no prophylaxis. We excluded patients with eGFR lower than 30 mL per min/1·73 m2, previous dialysis, or no referral for intravenous hydration. Randomisation was stratified by predefined risk factors. The primary outcome was incidence of contrast-induced nephropathy, defined as an increase in serum creatinine from baseline of more than 25% or 44 μmol/L within 2-6 days of contrast exposure, and cost-effectiveness of no prophylaxis compared with intravenous hydration in the prevention of contrast-induced nephropathy. We measured serum creatinine immediately before, 2-6 days, and 26-35 days after contrast-material exposure. Laboratory personnel were masked to treatment allocation. Adverse events and use of resources were systematically recorded. The non-inferiority margin was set at 2·1%. Both intention-to-treat and per-protocol analyses were done. This trial is registered with, number NCT02106234.

Findings: Between June 17, 2014, and July 17, 2016, 660 consecutive patients were randomly assigned to receive no prophylaxis (n=332) or intravenous hydration (n=328). 2-6 day serum creatinine was available for 307 (92%) of 332 patients in the no prophylaxis group and 296 (90%) of 328 patients in the intravenous hydration group. Contrast-induced nephropathy was recorded in eight (2·6%) of 307 non-hydrated patients and in eight (2·7%) of 296 hydrated patients. The absolute difference (no hydration vs hydration) was -0·10% (one-sided 95% CI -2·25 to 2·06; one-tailed p=0·4710). No hydration was cost-saving relative to hydration. No haemodialysis or related deaths occurred within 35 days. 18 (5·5%) of 328 patients had complications associated with intravenous hydration.

Interpretation: We found no prophylaxis to be non-inferior and cost-saving in preventing contrast-induced nephropathy compared with intravenous hydration according to current clinical practice guidelines.

Funding: Stichting de Weijerhorst.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Contrast Media / adverse effects*
  • Costs and Cost Analysis
  • Creatinine / blood
  • Female
  • Fluid Therapy* / economics
  • Fluid Therapy* / methods
  • Glomerular Filtration Rate
  • Humans
  • Infusions, Intravenous
  • Iohexol / adverse effects
  • Iohexol / analogs & derivatives*
  • Kidney Diseases / chemically induced
  • Kidney Diseases / prevention & control*
  • Male
  • Prospective Studies
  • Risk Factors
  • Sodium Chloride / administration & dosage
  • Treatment Outcome


  • Contrast Media
  • Iohexol
  • Sodium Chloride
  • iopromide
  • Creatinine

Associated data