This document provides information on contrast-induced nephropathy (CIN) including its definition, importance of prevention, risk factors, and prevention strategies based on clinical trials. CIN is defined as a 25% increase or 0.5 mg/dL absolute increase in creatinine 2-5 days after contrast. Prevention is important as CIN can cause prolonged hospitalization, dialysis, and increased mortality. High risk groups include those with GFR <60 mL/min, especially diabetics. Prevention strategies shown to be effective include intravenous hydration before and after contrast, using low- or iso-osmolar contrast, and oral acetylcysteine. The document discusses various prevention strategies and concludes hydration and choosing

1. Prevention of Contrast-Induced
Nephropathy (CIN)
Sepehr Khashaei, MD
Assistant professor
Department of Internal Medicine

2. What will be covered today?
• Definition of CIN
• Why is prevention of CIN important?
• Some other information/statistics about CIN
• Who is at high risk for CIN?
• Information and conclusions based on
outcomes from clinical trials
• Simple measures for prevention
• Cost to patients.
• References.
• Questions and discussion.

3. Please save all your
questions and
discussions for the end.

4. Definition of CIN
• CIN is defined as an increase in baseline serum
creatinine level of 25% or an absolute increase
of 0.5 mg/dL, 2 to 5 days after radiocontrast
administration.

5. Why is prevention of CIN important?
• Radiocontrast administration is a common cause of
hospital-acquired acute renal failure (10% of cases).
• In its severe form, CIN is associated with clinically
significant morbidity and mortality, including
prolonged hospitalization, requirement for dialysis, and
an increased risk for death.
• CIN increases the costs of medical care by at least
extending the hospital stay.
• There is no specific treatment once CIN develops, and
management must be as for any cause of ATN, with
focus on maintaining fluid and electrolyte balance. The
best treatment of CIN is prevention.

6. Some other information/statistics
about CIN
• Individuals with pre-existing renal
insufficiency and diabetes are much more
likely to experience contrast-induced
nephropathy.
• Typically, serum creatinine levels begin to
increase at 48-72 hours, peak at 3 to 5 days,
and return to baseline within another 3-5
days.
• In most cases there is no permanent sequelae.

7. Some data from 2004
• More than a million radiocontrast procedures
were performed annually.
• Incidence of CIN was 150,000/yr.
• 1% of CIN required dialysis and caused
prolongation of hospital stay to an average of
17 days.
• For episodes that did not require dialysis,
there was prolongation of hospital stay by 2
days on an average.

8. Total CT scans with contrast
done in 2009 at all UNM
facilities where 18,350.

9. Who is at high risk?
• Patients with GFR <60 ml/min particularly if
diabetic.
• UNM radiology department uses a creatinine
of >1.0 for a female and >1.3 for a male as
definition of a high risk patient.

10. Proposed interventions studied in
literature
• Saline hydration
• Diuretics
• Mannitol
• Intravenous bicarbonate
• Saline plus Mannitol
• Saline plus diuretics
• Oral hydration
• Calcium channel antagonists (i.e. nifedipine)
• Theophylline
• Endothelin receptor antagonists
• Dopamine
• Fenoldopam (dopamine-1 receptor)
• Antioxidant N-acetylcysteine
• Iso-osmolar or low-osmolal contrast agents
• Hemodialysis
• Hemofiltration
• Use of MRI in place of CT
• Atrial natriuretic peptide
• Statins
• Ascorbic acid

11. Simple measures for prevention
• The use of lower doses of contrast.
• Avoidance of repetitive contrast studies that
are closely spaced (within 48-72 hours).
• Avoidance of volume depletion
• Avoidance of NSAIDS
• Avoidance of nephrotoxic drugs

12. Information and
conclusions based on
outcomes from
clinical trials

13. • Patients with near-normal kidney function are
at little risk for CIN (about 3%) and few
precautions are necessary other than
avoidance of volume depletion.

14. • The patients at increased risk for contrast-
induced nephropathy are diabetics (especially
insulin-dependent diabetics) and patients with
underlying renal insufficiency (12-50%
incidence).

15. • The effects of poor hydration and the volume
of contrast medium administered are less
clear but are possible risk factors.

16. • Risk factors may be additive.

17. • The risk for CIN does not appear to be
influenced by the patient’s age or sex.

18. • Absence of risk factors does not preclude the
development of CIN.

19. • Although theoretically beneficial, there is little
evidence in support of vasodilators (such as
nifedipine, captopril, prostglandin E, low-dose
dopamine, fenoldopam, endothelin receptor
antagonists, and theophylline) in reducing risk
of CIN.

20. • Infuse NS (Grade 1B) at a rate of 1ml/Kg per
hour starting at least two and preferably 6-12
hours prior to the procedure, and continuing
for 6 to 12 hours after contrast administration.
The duration of administration of fluid should
be directly proportional to the degree of renal
impairment (e.g., should be longer for
individuals with more severe renal
impairment). Dose should be adjusted
depending on patient’s underlying medical
condition and their level of hydration.
Hydration with NS was superior to 1/2NS at
least in one clinical trial.

21. • Intravenous hydration is superior to oral
hydration. Oral hydration with water alone
should not be used.

22. • Use, if possible, ultrasonography, MRI without
gadolinium contrast, or CT scanning without
radiocontrast agents.

23. • Based on limited literature, it is difficult to be
certain that gadolinium used in MRI scanning
is completely free of nephroxicity in high-risk
patients. Also, gadolinium-based imaging
should not be performed, if at all possible, in
patients with GFR <30 ml/min because of risk
of nephrogenic systemic fibrosis. In such
patients, if a contrast study is necessary, use
of low-osmolar or isoosmolar iodinated
contrast media, using all the preventive
measures that are available, is preferred.

24. • Oral acetylcysteine administed as 1200mg
twice daily the day before and the day after
the procedure (Grade 2B). Do not use iv
acetylcysteine for prevention of CIN (Grade
2B).

25. • Do not use mannitol or other diuretics
prophylactically (Grade 1B).
• However, diuretics may be required to treat
volume overload.

26. • Do not use high osmolal agents (1400 to 1800
mosmol/KG) (Grade 1A).

27. • Use nonionic isoosmolar agents such as
iodixanol (Visipaque) or nonionic low-osmolal
agents such as iopamidol (Isoview) (Grade 1B)
if a contrast study is necessary.

28. Low or iso-osmolar nonionic contrast
• Decreased incidence of CIN.
• Cost reductions
• Increased patient tolerability
• Decreased hypersensitivity reactions
• The benefit is higher in diabetics with renal insufficiency
• Now administered for the majority of radiologic procedures
that use iv contrast media.
• There appears to be little or no advantage in the prevention
of CIN when compared to ionic hyperosmolar agents in
patients with normal renal function.
• At UNM we use iopamidol (a low-osmolar non-ionic agent)
on all adults who have contrast studies regardless of their
GFR.

29. • Among patients with stage 3 and 4 CKD do not
perform prophylactic hemofiltration (see
below) or hemodialysis (Grade 1B).
• Hemofiltration is expensive, logically
cumbersome and associated with significant
risks, its effectiveness compared to other less
expensive strategies is not well established,
and the reported benefits are implausible.
Therefore currently prophylactic
hemofiltration is not recommended.

30. • Among patients with stage 5 CKD, most
suggest hemodialysis after contrast exposure
if there is already a functioning access (Grade
2C) (although there is lack of sufficient data).
Do not place a temporary access for
prophylactic hemodialysis in these patients.

31. • The effectiveness of sodium bicarbonate
treatment to prevent CIN remains uncertain.
Earlier reports probably overestimated the
magnitude of any benefit, whereas larger,
more recent trials have had neutral results.
Large multicenter trials are required to clarify
whether sodium bicarbonate has value for
prevention of CIN before routine use can be
recommended.

32. Cost to patients
• One bag of NS (1000cc) = $40.00
• 1200mg of acetylcysteine = $5.00
• One day on 4-W = $5,489 (Medicine Subacute)
• One day on 4-E = $7,129 (Med/surg Subacute)
• One day on 4-S = $6, 863 (Orthopedics)
• One day on 5-W = $ 4,049 (General Medicine)
• One day on 5-S = $6,152 (NeuroScience)
• One day on 6-S = $7,580 (General Surgery)
• One day on 7-S = $8,517 (Cardiothoracic)
• One day on Medical ICU = $7,747

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37. Questions and
discussion