Lecure on managing contrast reactions.
description of contrast media control systems to assure compliance with JCAHO standards
File: uwhc-contrast-media-control-systems.pdf
Instructions and link to exam on uwhealth.org
File: contrast-reaction-test-instructions.pdf
Extensive tutorial on contrast agents
File: contrast-agents-tutorial.pdf
Drug selection chart for adult patients
File: contrast-rx-dosage-adult.pdf
medication and dosage charts for pediatric patients
File: contrast-rx-dosage-peds.pdf
Interventional Radiology Bicarb Protocol for CIN
Indication
Contrast induced or associated AKI is felt to be a real albeit rare entity. The most important risk factor seems to be pre-existing severe renal insufficiency (AKI or eGFR<30mL/min/1.73m2. The major preventative action to mitigate the risk of CIN is to provide intravenous volume expansion (see Hydration protocol). One possible protocol would be 0.9% saline at 100 ml/hr, beginning 6-12 hrs before contrast and continuing for 4-12 hours after contrast in the inpatient setting.
A study from JAMA printed in May of 2004 indicates that hydration with a bicarbonate solution may better prevent contrast induced nephropathy than NS hydration. Most renal failure is associated with metabolic acidosis and low urinary pH. NS may contribute to acidosis while the bicarbonate solution will buffer the pH.3. Subsequent studies have challenged this practice, and results are not definitive at this time. However, given the low cost and lack of side effects, it is unlikely to be harmful and could be added to the hydration regimen. Other practices, such as administration of N-acetyl cysteine, are not supported by the literature. Cessation of nephrotoxic medications may also be helpful when feasible.
Administration/Dosing
Solution: 150 mEq NaHCO3 in 1000cc D5W
1 hour prior to contrast: Initial IV bolus – 3ml/kg/hour x 1 hour
After 1 hour bolus: 1ml/kg/hour during contrast exposure and 6 hours post contrast.
References
- Levy EM, Viscoli CM, Hurwitz RI. The effect of acute renal failure on mortality: a cohort analysis. JAMA. 1996; 275: 1489-1494.
- McCullough PA, Wolyn R, Rocher LL, et al. Acute renal failure after coronary intervention. Am J Med.1997; 103: 368-375.
- Merten GJ, et al. Prevention of contrast-induced nephropathy with sodium bicarbonate: a randomized controlled trial. JAMA. 2004; 291: 2328-2334.
- 2004/Lisa Semmann, R.N., M.S., Interventional Radiology NP
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Purpose: reduce the number of patients with known allergies scanned at East Clinic, Digestive Health Center, and other non-hospital outpatient centers.
- If a patient is being scheduled for a contrast-enhanced CT and has an allergy to iodinated contrast or “contrast” then the study should be done at CSC, TAC or One South Park.
- If a patient is being scheduled for a contrast-enhanced MRI and has an allergy to gadolinium-based contrast or “contrast” then the study should be done at CSC, TAC or One South Park.
- If the patient has a list of 5 or more allergies to anything and has an order for a contrast-enhanced CT or contrast-enhanced MRI, then the patient should be scheduled at CSC, TAC or One South Park.
- If the caller tells the screener that they have had an “anaphylactic” or “anaphylactoid” reaction, and the patient has an order for a contrast-enhanced CT or contrast-enhanced MRI they should be scheduled at CSC or TAC. Please note that the schedulers are not obligated to search the medical records for the severity of reactions.
- Pre-medication is only indicated for those patients with known allergies to iodinated contrast or gadolinium-based contrast agents, and should be communicated at the physician level. (See Prophylaxis policy for patients allergic to IV contrast).
7/2020
What patients require premedication prior to IV contrast?
A prior allergic-like or unknown type reaction to the same class of contrast medium is considered the greatest risk factor for predicting future adverse events. Premedication prior to administration of intravenous contrast is recommended in this group of patients.
In general, patients with unrelated allergies are at a 2- to 3-fold increased risk of an allergic-like contrast reaction, but due to the modest increased risk, restricting contrast medium use or premedicating solely on the basis of unrelated allergies is not recommended. Patients with shellfish or povidone-iodine (e.g., Betadine®) allergies are at no greater risk from iodinated contrast medium than are patients with other allergies (i.e., neither is a significant risk factor).
In patients with reported prior contrast allergy or reaction:
- Ascertain the specific details of the prior reaction. Determine:
- If the patient had a true reaction to intravascular contrast material
- Type of contrast used (if available)
- Type of reaction and severity
- Treatment and its result
- Level of patient anxiety
- In addition to intravascular contrast administration, the following scenarios should be considered in patients with contrast allergy:
- Administration of oral contrast. 1-2% of oral contrast could be absorbed. So for someone who has a severe contrast allergy, they should get dilute barium as an oral contrast agent. If prior mild reaction and minimum risk of perforation/leak, no need to premedicate. For moderate reactions or risk of peritoneal leak, consider premedication or dilute barium alternate oral contrast.
- Arthrograms. Because allergic-like reactions are dose-independent, and arthrograms use a needle and cross the bloodstream, use the same premedication strategy for arthrograms that is used for intravenous media. For patients with known contrast allergies, appropriate to premedicate or switch to US if possible.
- Hysterosalpingograms: In patients with patent fallopian tubes, there is peritoneal spill of contrast. Intraperitoneal contrast is absorbed (intraperitoneal=intravascular). Because of the dose independence, premedication for HSGs should be performed in patients with known contrast allergies.
- Determine if an examination without contrast can provide adequate diagnostic information.
- If still convinced of the need for intravascular contrast, the service requesting the scan should:
- Contact the radiologist scheduled on service for the proposed date of the study (GI/GU, CT, Angiography, Neuroradiology, or on-call resident for overnight/weekend Emergency Department patients). If the staffing schedule is not available for the proposed date of the examination, then the Chief of the GI/GU Service (Dr. Perry Pickhardt), CT Service (Dr. Meghan Lubner), Angiography/Interventional Service (Dr. Orhan Ozkan), or Neuroradiology Service (consultant for the day) should be contracted.
- Discuss why an alternative imaging method will not suffice
- If the risk is determined to be acceptable; schedule the contrast examination and transmit prophylaxis instructions.
- Routine Contrast Reaction Prophylaxis (12 hour):
- Methylprednisolone (Medrol)
- 32 mg by mouth at 12 and 2 hours before contrast injection.
- Diphenhydramine (Benadryl):
- 50 mg intramuscular or oral 1 hour before contrast injection OR
- 50 mg (or 25 mg per height/weight indication) intravenously 15-20 min before contrast injection
Note: The Benadryl must be used with the proviso that the patient does not drive a car or operate heavy machinery 4-6 hours after the Benadryl is administered.
NEJM 1987; 317: 845-849.
- If a patient is unable to take oral medication, consider the 5 hr regimen detailed in #6. Alternatively the methylprednisolone may be substituted with 200 mg hydrocortisone IV at 13, 7, and 1 hour before contrast administration. If a patient is allergic to diphenhydramine in a situation where diphenhydramine would otherwise be considered, an alternate anti-histamine without cross-reactivity may be considered, or the anti-histamine portion of the regimen may be dropped.
- Rapid Contrast Reaction Prophylaxis (5 hours):
- To be used only in a truly urgent situation after discussion between the requesting service and the appropriate radiology service.
- The requesting service must place a note in HealthLink outlining the necessity of contrast-enhanced examination and the rapid prohpylaxis protocol.
- Hydrocortisone:
- 200 mg intravenously 5 and 1 hour before contrast injection
- Diphenhydramine (Benadryl):
- 50 mg intravenously 1 hour before contrast injection
- In addition to steroid premedication, changing the culprit iodinated agent if known may decrease the risk of repeat allergic reaction. Consider substitution of an iso-osmolar agent (iodixanol) if a low osmolar agent was previously administered.
Greenberger PA et al. Emergency administration of radiocontrast media in high-risk patients. J Allergy CLin Immunol. 1986; 77(4): 630-634.
Mervak BM, Cohan RH, Ellis JH, Khalatbari S, Davenport MS. Premedication administered 5 hours before CT compared with a Traditional 13-hour Oral regimen. Radiology 2017; 285(2), 425-433..
McDonald JS, Larson NB, Kolbe AB et al. Prevention of Allergic-like Reactions at Repeat CT: Steroid Pretreatment versus Contrast Material Substitution. Radiology 2021; 000:1-8.