FAQ- IV Contrast

What is recommended for patients who need allergy premedication prior to intravenous injection of CT and MR contrast?

Elective Premedication:

  • Prednisone 50mg PO at 13, 7, and 1 hour before IV contrast. Benadryl 50mg PO/IM at 1 hour before IV contrast.
  • Methylprednisolone 32 mg PO at 12 and 2 hours before IV contrast. Benadryl 50 mg PO/IM at 1 hour before IV contrast is optional.
    Note: Outpatients may take their final doses up to 2 hours before the prcoedure given travel and registration time.

 

Urgent premedication: in order of preference

  • SoluMedrol 40 mg IV or SoluCortel 200 my IV q4 hours, 4-5 hours before IV contrast.  Benadryl 50 mg IV 1 hour before IV contrast.
  • Decadron 7.5 mg IV q4 hours, 4-5 hours before IV contrast. Benadryl 50 mg IV 1 hour before IV contrast.  Use for patients allegic to methylprednisolone.
  • SoluMedrol 40 mg IV or SoluCortel 200 mg IV, plus Benadryl 50 mg IV at 1 hour before IV contrast.  No proven evidence for efficacy.
Reference: ACR Manual on Contrast Media, Version 10.3; 2017.

What are the recommendations regarding Metformin usage in patients who receive intravenous iodinated contrast material?

  • Updated list of Metformin medications:
    • Metformin: Glucophage, Glucophage XR, Fortamet, Glumetza, Riomet.
    • Glyburide/metformin: Glucovance.
    • Glipizide/metformin: Metaglip.
    • Pioglitazone/metformin: ActoPlus Met, ActoPlus Met XR.
    • Repaglinide/metformin: Prandimet.
    • Rosiglitazone/metformin: Avandamet.
    • Saxagliptin/metformin: Kombiglyze XR.
    • Sitagliptin/metformin: Janumet, Janumet XR.
    • Linigliptin/metformin: Jentadueto.

 

  • New tiered system for stopping/restarting medications:
    • Category I: Patients with eGFR >30 and no clinical evidence for acute kidney injury do not need to discontinue medications.
    • Category II: Patients with eGFR <30 or known acute kidney injury or with recent aortic/renal artery catheterization procedure: withhold medication for 48 hours, contact referring providers to determine when it is safe to restart medication (check serum creatinine levels).
Source: ACR Manual on Contrast Media, Version 10.1; 2015.

What is the policy regarding thyroid conditions and iodinated contrast?

  • Patients undergoing radioactive iodine therapy or nuclear medicine scanning: iodinated contrast can interfere with uptake of radioactive iodine tracers. As such, recommend washout period of 3-4 weeks for hyperthyroid patients, and 6 weeks for hypothyroid patients.
  • Patients suffering from acute thyroid storm: avoid iodinated contrast, as it can potentiate thyrotoxicosis.
  Source: ACR Manual on Contrast Media, Version 10.3; 2017.

What is the policy regarding renal insufficiency and intravenous contrast for CT scan?

Our current criteria for patients who need to obtain a serum creatinine and eGFR:

  • All Inpatients and ER patients
  • Outpatients with age > 60 years
  • Patients with any of the following:
    • History of renal disease: on dialysis, renal transplant, renal surgery, renal cancer or single kidney.
    • Hypertension
    • Diabetes

Generally, for outpatients and emergency department patients, the 4-variable MDRD equation will be used to calculate estimated glomerular filtration rate (eGFR). Alternatively, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation can be used.

Estimated GFR stratification criteria are as follows:

  • eGFR of 30 and above: proceed with IV contrast. Encourage oral hydration
  • eGFR 15-29: consider alternative studies or withholding IV contrast. If patient is on dialysis, then IV contrast can be administered.

Dialysis patients:

  • Unless there is an unusually large volume of IV contrast (to include multiple studies within a 24 hour period) or substantial cardiac dysfunction (heart failure), there is NO need to contact nephrology for urgent dialysis afterwards.
Source: ACR Manual on Contrast Media, Version 10.3; 2017.

Is it safe for patients with renal failure to receive intravenous gadolinium contrast for MRI examinations?

With more data coming in regarding the incidence of Nephrogenic Systemic Fibrosis (NSF) in patients with renal insufficiency receiving gadolinium-based contrast agent, the ACR has categorized existing Gadolinium-based agents on the market according to risk of causing NSF. Currently, none of our practice sites utilize any Group I agents listed below:

  • Group I agents (associated with greatest number of NSF cases): Omniscan, Magnevist, OptiMARK.
  • Group II agents (associated with few, if any, NSF cases): MultiHance, ProHance, Gadavist, Dotarem).
  • Group III agents (limited data on NSF risk): Eovist.,

The following policy has been adopted in our radiology department:

Our current criteria for patients who need to obtain a serum creatinine and eGFR:

  • All inpatients
  • Outpatients and ER patients with any of the following:
    • History of renal disease: on dialysis, renal transplant, renal surgery, renal cancer, or single kidney.
    • Hypertension.
    • Diabetes.

Estimated GFR stratification criteria are as follows:

  • eGFR 60 or greater (National Kidney Foundation stages 1 or 2 chronic kidney disease): no restrictions.
  • eGFR 30-59 (stage 3 chronic kidney disease): no restrictions.
  • Outpatients with eGFR less than 30 (stages 4 and 5 chronic kidney disease): Use Group II Gadolinium-based agents only.

Hemodialysis patients:

  • Should have a dialysis session within 24 hours of gadolinium administration.
  • Of note, peritoneal dialysis may be less effective in removing gadolinium from the body.
Source: ACR Manual on Contrast Media, Version 10.3; 2017.

When do eGFR lab draws need to be performed before IV contrast administration for CT and MRI?

Patient Condition eGFR requirement
Dialysis patients No eGFR required (not helpful).
Patients with acute kidney injury No eGFR required (not helpful).
Inpatients eGFR within 2 days of study.
Outpatients/ED with no prior eGFR If no risk factors: no eGFR required. With risk factors: eGFR required.
Outpatients/ED with most recent eGFR ≥45 If no risk factors, prior eGFR 60 or more: no new eGFR needed.
With risk factors and/or eGFR 45-59, eGFR should be from within 6 weeks of study.
Outpatients/ED with most recent eGFR ≤44 Obtain eGFR within 2 weeks of study.
Source: ACR Manual on Contrast Media, Version 10.3; 2017.

Which types of intravenous access are suitable for the administration of contrast materials?

For most contrast-enhanced CT and MR exams, a 22-gauge or larger IV is preferable, but a 24 gauge IV may be adequate for hand injections.

For CT angiography exams (e.g. rule out PE, peripheral runoffs), as well as multiphase CT exams (e.g. liver and pancreas protocol exams), an 20-gauge or larger IV is preferred given the higher injection rates of contrast.

Some 9.5 to 10 French central venous catheters can be used for power injection of contrast (depending on specific manufacturer recommendations), provided that venous backflow and saline injection can be performed without resistance.

Tunneled catheters and PICC’s are in general not approved for power injector use. However, Power Port’s and Power PICC’s manufactured by Bard are approved for use with power injectors. If you are interested in these products, you should consult with the surgeon or intravenous therapy team at your institution regarding their availability.

Intra-osseous access: humeral placement preferred over tibial access; injection rates up to 5 mL/sec are possible. A local anaesthetic infusion is needed in non-sedated patients prior to contrast infusion.

Source: ACR Manual on Contrast Media, Version 10.3; 2017.

What are recommendations for IV contrast administration for pregnant patients?

  • There are currently no contraindications to IV iodinated contrast for CT scans in pregnant patients.
  • Given the unknown effects of Gadolinium MR contrast agents on the fetus, decision to use Gadolinium contrast should be made on a case-by-case basis, with patient informed consent obtained.
Source: ACR Manual on Contrast Media, Version 10.3; 2017.

What are the recommendations for breast-feeding patients who receive intravenous contrast for either CT or MRI examinations?

There is a tiny amount of contrast that is excreted in breast milk.  Patients who receive either iodinated contrast or gadolinium may continue breast-feeding after the examination without interruption.  Patients may also choose to stop breast feeding for 12-24 hours afterwards.

Source: ACR Manual on Contrast Media, Version 10.3; 2017.

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