After administration of intravascular iodinated contrast media Contrast-Induced Nephropathy (CIN), also known as Contrast-Induced Acute Kidney Injury (CIAKI), may occur. CIN/CI-AKI is associated with increased risk of dialysis and mortality. No treatment exists for CIN/CI-AKI, therefore the focus lies on prevention. Clinical practice guidelines for the prevention of CIN/CI-AKI exist and are implemented in most hospitals. Generally, intravascular volume expansion with normal saline is recommended as prophylaxis.

Earlier this year the results of the AMACING study (A MAastricht Contrast-Induced Nephropathy Guideline study) were published in The Lancet (NL47173.068.14/METC 14-2-006; Clinical Trials.gov NCT02106234; http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(17)30057-0/fulltext). These results show that for the greater part (>90%) of patients considered to be at risk of CIN/CI-AKI by the guidelines, withholding prophylaxis is non-inferior to giving standard intravenous prophylactic hydration in the prevention of CIN/CI-AKI. Furthermore, the standard prophylactic hydration confers some risk (5.5% complications of intravenous hydration were recorded in the AMACING study).

As a result the clinical protocol in the Maastricht University Medical Centre (MUMC+) has been adapted, and patients with an estimated Glomerular Filtration Rate (eGFR) >29mL/min/1.73m2 no longer receive intravenous prophylactic hydration before or after procedures with intravascular iodinated contrast material administration.

CINART is a one year prospective observational study with the aim to evaluate the consequences of the protocol change for 1. for incidences of CIN/CI-AKI, dialysis and mortality, 2. for clinical practice in terms of patient burden (complications of prophylaxis), hospital burden (extra hospitalisations for prophylaxis), and costs, as derived from the number of elective procedures carried out in patients formerly eligible for prophylaxis.

Inclusion Criteria:

• referred for an elective procedure with intravascular iodinated contrast administration at Maastricht University Medical Centre
• eGFR30-44mL/min/1.73m2 OR eGFR45-59mL/min/1.73m2 + DM OR eGFR45-59mL/min/1.73m2 + >1 risk factor (>age >75 years, anaemia, cardiovascular disease, prescribed NSAID or Diuretic medication) OR multiple myeloma/lymphoplasmacytic lymphoma with small chain proteinuria.

Exclusion Criteria:

• eGFR<30mL/min/1.73m2
• Dialysis/renal replacement therapy
• emergency procedure
• intensive care patient

Patients at risk of CIN/CIAKI according to the guidelines and an eGFR between 30-59mL/min/1.73m2, who are referred for an elective procedure with intravascular iodinated contrast administration at the MUMC+ after the protocol change i.e. the threshold for prophylactic intravenous hydration has been lowered to eGFR<30mL/min/1.73m2.