Introduction
Contrast induced nephropathy (CIN) is defined as a serum creatinine rise of 25% (or 44 µmol/l) from pre-scan levels. It is associated with both longer hospital stay and increased mortality.
Risk Factors
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- Stage 3B CKD or below
- Diabetes
- Acute Kidney Injury
- Reduced intravascular volume (dehydration, hypotension, CCF)
Treatment
Risk reduction
-
- Ensure investigation is necessary
- Discuss alternatives with radiology
- Identify and correct reversible risk factors (dehydration, hypovolaemia)
Withhold nephrotoxic drugs
-
- For 48 hours pre/post-scan: NSAIDs/COX-2 inhibitors
- Consider withholding ACE inhibitors, Angiotensin-2 receptor blockers
- For 24 hours pre +/- post-scan (depending on clinical need): Diuretics.
- Metformin should be stopped for 48 hours after the scan. (It is nephrotoxic, but can cause lactic acidosis if CIN occurs)
Renal protection
Give either Sodium Chloride or Sodium Bicarbonate as follows:
-
- IV 0.9% Sodium Chloride
- 1000ml at 83ml/hour
- Both 12 hours pre and 12 hours post scan
or
-
- IV 1.26% Sodium Bicarbonate
- 500ml at 71ml/hour
- Starting 1 hour before and continuing for 6 hours after
Note: There is not sufficient evidence to recommend N-Acetylcysteine. Discuss with renal/radiology prior to prescribing this if indicated.
Check Post-Scan Renal Function
On day 2-3 post scan.
This should be handed over to the GP if the patient is discharged after the scan.
Renal protection, [StaffNet Source]
