C. Miscellaneous
C.1. Contrast Medium Extravasation
C.2. Pulmonary Effects of Iodine-based Contrast Media
C.3. Effects of Contrast Media on Blood and Endothelium
C.3.1.1. Iodine-based contrast media
C.3.2.1. Iodine-based contrast media
C.3.2.2. Gadolinium-based contrast media
C.4. Contrast Media and Catecholamine Producing Tumors (pheochromocytoma and paraganglioma)
C.6. Interaction with Other Drugs and Clinical Tests
C.7. Safety of Ultrasound Contrast Media
C.8. Safety of Barium Contrast Media
C.9. Pediatric Use of Contrast Media
C.10. Off-label Use of Contrast Media
C. MISCELLANEOUS
C.1. Contrast Medium Extravasation
Type of injuries |
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Risk factors |
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Technique-related |
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Patient-related |
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To reduce the risk |
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Management
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C.2. Pulmonary Effects of Iodine-based Contrast Media
Pulmonary adverse effects |
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Patients at high risk |
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To reduce the risk of pulmonary adverse effects |
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C.3. Effects of Contrast Media on Blood and Endothelium
C.3.1. Thrombosis
C.3.1.1. Iodine-based contrast media
The clinically important adverse effect of iodine-based contrast media on blood and endothelium is thrombosis.
It is recognized that:
- All contrast media have anticoagulant properties, especially ionic agents.
- High-osmolar ionic contrast media may induce thrombosis due to endothelial damage, particularly in phlebographic procedures.
- Drugs and interventional devices that decrease the risk of thromboembolic complications during interventional procedures minimize the importance of the effects of contrast media.
Guidelines
- Meticulous angiographic technique is mandatory and is the most important factor in reducing thromboembolic complications.
- Low- or iso-osmolar contrast media should be used for diagnostic and interventional angiographic procedures including phlebography.
C.3.2. Sickle Cell Disease
C.3.2.1. Iodine-based contrast media
- In patients with sickle cell disease, high-osmolar iodine-based contrast agents may cause red cell sickling, leading to hemolysis and small vessel occlusion.
- Low- or iso-osmolar iodine-based contrast agents produce no more adverse events in patients with sickle cell disease than in the normal population.
Guidelines
- Use low- or iso-osmolar iodine-based contrast agents.
- Hydrate patients before contrast medium administration.
C.3.2.2. Gadolinium-based contrast media
- The smaller doses of gadolinium-based agents compared to iodine-based agents reduce the osmolar load, so contrast medium osmolality is unlikely to be a significant problem.
- No adverse events suggestive of red blood cell sickling have been reported after gadolinium-based contrast agents.
Guidelines
- Use any gadolinium-based contrast agent.
- No special preparation is necessary.
C.4. Contrast Media and Catecholamine Producing Tumors (pheochromocytoma and paraganglioma)
Preparation
a) Before intravenous iodine- or gadolinium-based contrast medium: No special preparation is required.
b) Before intra-arterial iodine-based contrast medium: α- and β-adrenergic blockade with orally administered drugs under the supervision of the referring physician is recommended.
Recommended contrast medium
Iodine-based: Non-ionic agent.
Gadolinium-based: Any agent.
C.5. Pregnancy and Lactation
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Iodine-based agents |
Gadolinium-based agents |
Pregnancy |
a) In exceptional circumstances, when radiographic examination is essential, iodine-based contrast media may be given to the pregnant female. b) Following administration of iodine-based agents to the mother during pregnancy, thyroid function should be checked in the neonate during the first week. |
a) When there is a very strong indication for enhanced MRI, the smallest possible dose of one of the most stable gadolinium contrast agents (see Contrast agents: Intermediate and lowest risk of NSF, A.3.2.) may be given to the pregnant female.
b) Following administration of gadolinium-based agents to the mother during pregnancy, no neonatal tests are necessary. |
Lactation |
Breast feeding may be continued normally when iodine-based agents are given to the mother. |
Breast feeding should be avoided for 24 hours after contrast medium if high-risk agents are used. |
Pregnant or lactating mother with renal impairment |
See renal adverse reactions (B.2.). No additional precautions are necessary for the fetus or neonate. |
Do not administer gadolinium-based contrast agents. |
C.6. Interaction with Other Drugs and Clinical Tests
General recommendation |
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Be aware of the patient’s drug history. Keep a proper record of the contrast medium injection (time, dose, name). Do not mix contrast media with other drugs in tubes and syringes. |
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Drugs needing special attention |
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Metformin |
Refer to renal adverse reactions section (B.4.). |
Nephrotoxic drugs Cyclosporine Cisplatin Aminoglycosides Non steroid anti-inflammatory drugs |
Refer to renal adverse reactions section (B.2.). |
ß-blocker |
ß-blockers may impair the management of bronchospasm and the response to adrenaline. |
Interleukin-2 |
Refer to late adverse reactions section (A.2.). |
Biochemical assays |
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Recommendation |
Do not perform non-emergency biochemical analysis of blood and urine collected in the 24 hours after contrast medium injection. |
Isotope studies and/or treatment |
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Thyroid |
Patients undergoing therapy with radioactive iodine should not have received iodine-based contrast media for at least two months before treatment. Isotope imaging of the thyroid should be avoided for two months after iodine-based contrast medium injection. |
Bone, red blood cell labeling |
Avoid iodine-based contrast medium injection for at least 24 hours before the isotope study. |
C.7. Safety of Ultrasound Contrast Media
Statements |
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Contraindication |
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Type and severity of reactions |
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To reduce the risk |
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Treatment |
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C.8. Safety of Barium Contrast Media
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Recommended action |
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Contraindications |
Integrity of gut wall compromised |
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Previous allergic reactions to barium products |
Use iodine-based water-soluble contrast media and be prepared to treat a reaction. |
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Cautions |
Bowel strictures |
Use only small amounts. |
Extensive colitis |
Avoid barium enemas. |
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Complications |
Reduced bowel motility |
Encourage fluid intake. |
Venous intravasation |
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Aspiration |
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C.9. Pediatric Use of Contrast Media
- Safety considerations when using contrast media in neonates, infants and children are similar to, but not the same as, in adults.
- Contrast agent dose must be adjusted for patient age and weight.
- Age-specific normal values of serum creatinine etc. must be used.
- For iodine-based contrast media, non-ionic agents should be used.
- For gadolinium-based contrast media, high-risk agents should be avoided.
- The Summary of Product Characteristics for the contrast agent should be consulted, because not all contrast media are approved for use in children.
- If no suitable contrast agent approved for use in children is available, informed consent for off-label use must be obtained from the parents. However, if use of a specific contrast agent in children is absolutely contra-indicated, it may not be used, even with informed consent.
C.10. Off-label Use of Contrast Media
- Off-label use of diagnostic and therapeutic medication is common.
- The Summary of Product Characteristics (SPC) or label should be checked to see if the proposed contrast medium use is approved for the particular patient and indication.
- Choose a contrast medium which is approved for the particular patient and indication whenever possible.
- If there is no suitable approved contrast medium, the prescriber must tell the patient about the risks and benefits of off-label contrast medium use, and must obtain the patient’s informed consent to off-label contrast medium administration.