II. Risk Factors
III. Definition
- Postcontrast Acute Kidney Injury (Contrast-Induced Nephropathy)
- Onset within 48-72 hours of Intravenous Contrast exposure of at least one of the following criteria
- Serum Creatinine increased 0.3 mg/dl (some studies use 0.5 mg/dl) over baseline OR
- Relative increase of Serum Creatinine >50% (some studies use >25%) over baseline OR
- Urine Output decreased to 0.5 ml/kg/h for 6 hours
IV. Precautions
- Degree to which radiocontrast causes nephropathy is controversial
- Most recent studies find no significant impact on Acute Kidney Injury with radiocontrast if GFR>30 ml/min
- However, Serum Creatinine may transiently increase in 2-3% of patients
- Aulicky (2010) J Neurol Neurosurg Psychiatry 81(7):783-7 [PubMed]
- McDonald (2013) Radiology 267(1): 106-18 [PubMed]
- Ng (2010) AJR Am J Roentgenol 195(2): 414-22 [PubMed]
- Davenport (2013) Radiology 268(3): 719-28 [PubMed]
- McDonald (2014) Radiology 273(3): 714-25 [PubMed]
- Hinson (2017) Ann Emerg Med 69(5): 577-86 [PubMed]
- American College of Radiology (ACR) Recommendations
- ACR recommends no baseline Creatinine before scan if age <60, no renal disease, Hypertension, diabetes
- GFR >30 ml/min is sufficient to undergo radiocontrast scan
- References
- Morgenstern in Herbert (2019) EM:Rap 19(10): 4-6
- Spangler and Werner (2021) EM:Rap 21(8): 12-3
V. Prevention (Indicated for Acute Renal Failure Risk)
- Avoid concurrent Nephrotoxic Drugs
- See Nephrotoxic Drugs
- Avoid NSAIDs
- Use low osmolality (non-ionic) or iso-osmolal Contrast Material
- Allow 2-5 days between IV contrast procedures
- Exercise caution with IV Contrast in Diabetes Mellitus with eGFR <60 ml/min (CKD 3a)
- Hydrate before and after procedure (most important measure)
- Adjust for Congestive Heart Failure
- Oral Option: (non-caffeinated fluid)
- Take at least 500 ml before contrast
- Take 2500 ml over the 24 hours post-contrast
- IV Option: Intravenous Normal Saline
- Infuse 100 ml/hour saline for 4 hours pre-contrast
- Infuse 100 ml/hour for the 24 hours post-contrast
- IV Option: Intravenous Isotonic Bicarbonate
- Prepare 3 ampules of Sodium Bicarbonate (50 meq/ampule) in 850 cc D5W
- Give 3 ml/kg IV one hour before procedure and 1 ml/kg/hour for 6 hours post-procedure
- Reference
- Stuart (2007) Park Nicollet Primary Care Conference, Minneapolis, MN
- Adjust IV contrast dose
- Contrast Dose: (5 cc/kg)/(Serum Creatinine)
- Maximum total dose: 300 cc
-
Acetylcysteine (Mucomyst) for 3 days (questionable efficacy)
- Not typically used in U.S. (hydration is used instead)
- Indications
- Safe and low cost prevention (consider in all at risk patients)
- Chronic Kidney Disease
- Acute Renal Failure Risk Factors
- Diabetes Mellitus
- Protocol
- Used in combination with hydration protocol above
- Start day before contrast exposure
- High dose protocol (replaces the older, ineffective 600 mg dose)
- Mucomyst 1200 mg orall twice daily
- Give on the day before and the day of contrast administration
- Efficacy
- Initial studies showed risk of nephropathy reduced by 56%
- Recent data suggests that standard dose ineffective; higher dose may be effective
- References
- Williams (2008) Mayo Selected Topics in Internal Medicine, Lecture
- Trivedi (2009) Am J Med 122(9): 874 [PubMed]
- References
- Other agents to consider
- Calcium Channel Blocker for 24 hours before procedure
- Agents with no benefit
- Avoid Furosemide (Lasix)
- Avoid Mannitol
VI. Monitoring
- Recheck the Serum Creatinine in patients with Acute Renal Failure Risk within the first 3 days following contrast exposure
VII. References
- Mende (2001) CME Medicine Lecture, San Diego
- Maddox (2002) Am Fam Physician 66(7):1229-34 [PubMed]
- Quader (1998) Ann Vasc Surg 12:612-20 [PubMed]