CT Intravenous Contrast

Aka: CT Intravenous Contrast, Water-Soluble Iodinated Intravenous Contrast, Nonionic Iodinated Intravenous Contrast, Non-ionic Contrast Media, Low-Osmolality Contrast Media, LOMC, Intravenous Contrast, Anaphylactoid Reaction to Radiocontrast, Pretreatment of Contrast-Induced Anaphylactoid Reaction, Contrast Media Allergy, Contrast Media Reaction, Iodinated Contrast Reaction, Iodinated Contrast Dye, Iodixanol, Visipaque, Iopamidol, Isovue, Iopromide, Ultravist, Ioversol, Optiray

advertisement

II. Preparations

  1. See Radiographic Contrast Media (includes Oral Contrast and Gadolinium IV contrast for MRI)
  2. CT Intravenous Contrast is typically with Iodinated, Nonionic, Low-Osmolality Contrast Media (LOMC)
    1. Iodixanol (Visipaque)
    2. Iopamidol (Isovue)
    3. Iopromide (Ultravist)
    4. Ioversol (Optiray)

III. Contraindications: IV Contrast

  1. See Metformin under prevention below
  2. Pregnancy (relative contraindication)
    1. ACR recommends non-ionic, low osmolality iodinated agents if IV contrast is used
    2. Decision to use contrast (and for that matter CT)
      1. Based on clinical judgment that imaging IV benefits out-weigh risks
    3. Theoretical concern for fetal Thyroid conditions related to iodinated contrast
      1. Iodinated contrast crosses placenta
      2. No Teratogenicity has been found in animals with nonionic, low osmolality agents
  3. Radioactive Iodine-treated Thyroid disease (e.g. Graves Disease)
    1. Iodinated contrast competes for binding at Thyroid Gland with I-131 (results in ineffective treatment)
    2. Avoid iodinated contrast for 2 months following I-131 treatment
    3. Consult with endocrinlogy
  4. Serum Creatinine >1.5 to 2.0 mg/dl (e.g. GFR <30 ml/min)
  5. Serious IV contrast reaction history (e.g. Anaphylaxis)
    1. Mild to moderate reactions
      1. May be considered for IV Contrast use
      2. Use Pretreatment of Contrast-Induced Anaphylactoid Reaction described below
    2. Severe Reaction
      1. Do not use IV contrast if history of severe reaction

IV. Risk Factors: Contrast Reaction

  1. Most significant risks
    1. History of prior contrast-related anaphylactoid reaction (highest risk)
    2. Asthma, Allergic Rhinitis or atopy
    3. Ionic and/or high osmolality Intravenous Contrast media (older agents)
      1. Original hyperosmolar agents had adverse effect rates as high as 15%
        1. Compare with current low osmolality adverse effect rates of 0.2 to 0.7%
      2. Same major reaction (e.g. Anaphylaxis) rate for ionic vs nonionic agents
        1. Reaction Incidence: 1 per 170,000 administrations
      3. Mild to moderate reactions are more common with ionic agents and with high osmolality agents
      4. Most U.S. centers use non-ionic, low osolality Intravenous Contrast
  2. Other associated risks
    1. Older patient age
      1. >65 years old: 35 fatalities per million injections
      2. <65 years old: 4.5 fatalities per million injections
      3. Children have the lowest Incidence of IV contrast agent reactions
        1. Mild reaction rate for nonionic, low osmolality agents: 0.18%
    2. Renal Insufficiency
    3. Female gender
    4. Medication allergy or Food Allergy
    5. Comorbid conditions such as cardiovascular disease
    6. Concurrent Nephrotoxic Drugs such as NSAIDS
    7. Multiple drug allergies (especially if any prior medication-induced Anaphylaxis)

V. Risk Factors: Agents that do not increase contrast reaction (debunking myths)

  1. Seafood and shellfish do not increase the risk of Radiocontrast Material reaction
    1. The allergens in seafood and shellfish are Proteins (tropomyosins and parvalbumin), not Iodine
  2. Povidone Iodine (Betadine) reactions are a Contact Dermatitis
    1. Povidone Iodine Contact Dermatitis does NOT predispose to Radiocontrast Material reaction
  3. Iodine is NOT an allergan
    1. Do NOT add Iodine as an allergan in the EHR
    2. Iodine is an integral component to Thyroid Physiology
    3. Iodine is NOT an Antigen, as it is too small of a molecule to trigger an Antibody response
    4. Iodide is added to most Table Salt, and patients typically do not have a Anaphylaxis to salt
    5. Iodine does not increase the risk of Radiocontrast Material reaction
  4. References
    1. (2023) Presc Lett 30(7): 40
    2. Schabelman (2010) J Emerg Med 39(5): 701-7 [PubMed]

VI. Adverse Effects

  1. Anaphylactoid Reaction
    1. Immediate reaction to small dose (does not require pre-sensitization)
      1. Contrast with Anaphylaxis which is IgE mediated and requires allergen presensitization
      2. Histamine dependent response
      3. Associated with diffuse and Facial Edema, Dyspnea, Hypotension, laryngeal edema and Stridor, Wheezing, Hypoxia
    2. Emergency management (see Anaphylaxis)
      1. ABC Management
      2. Epinephrine 0.3 to 0.5 mg SQ q10-20 minutes
      3. Methylprednisolone 50 mg IV (for bronchospasm)
  2. Delayed reaction
    1. Constitutional symptoms occur >30 min post-contrast
    2. Management: Supportive
  3. Acute Tubular Necrosis (Acute Renal Failure)
    1. See Intravenous Contrast Related Acute Renal Failure
    2. Occurs more often if Acute Renal Failure Risk
  4. Local toxicity from extravasated Contrast Material (chemotoxic reactions)
    1. Apply ice to area and elevate
    2. Reaction worse with ionic contrast agents
      1. High osmolality agents (Hypaque, Conray)
      2. Ioxaglate meglumine (Hexabrix)
    3. Consider infusing contrast more slowly on future scans
  5. Other associated symptoms
    1. Nausea or Vomiting
    2. Flushing, warmth or chills
    3. Headaches
    4. Dizziness
  6. Physiologic Effects
    1. Anxiety
    2. Vasovagal Syncope
    3. Inotropic effects
    4. Neurologic effects

VII. Prevention

  1. See Intravenous Contrast Related Acute Renal Failure
  2. See Pretreatment of Contrast-Induced Anaphylactoid Reaction below
  3. Use nonionic low osmolality agents (typically standard in United States)
  4. Avoid concurrent use of Nephrotoxic Drugs
  5. Avoid Intravenous Contrast when Serum Creatinine >1.5 to 2.0 (guidelines vary per institution)
  6. Stop Metformin for 48 hours after contrast
    1. Theoretical risk of severe Lactic Acidosis
    2. May resume Metformin in 48 hours without additional testing unless indicated below
    3. Indications for Serum Creatinine prior to restarting Metformin
      1. Known renal dysfunction
      2. Increased risk of renal dysfunction following Intravenous Contrast exposure (e.g. CHF, Sepsis, ischemia)
  7. Consider N-Acetylcysteine before Intravenous Contrast
    1. See Intravenous Contrast Related Acute Renal Failure
  8. Hydrate before and after procedure
    1. Consider Normal Saline
    2. See Intravenous Contrast Related Acute Renal Failure

VIII. Management: Pretreatment of Contrast-Induced Anaphylactoid Reaction

  1. Indicated for prior radiocontrast reaction (mild to moderate)
    1. Do not give IV contrast if prior severe reactions (Anaphylaxis, cardiopulmonary collapse)
    2. Do not delay contrast for pretreatment in the evaluation acute, life-threatening conditions
  2. Efficacy
    1. Despite pretreatment, 12% of patients with prior reactions will have new reactions
      1. When reactions do occur despite pretreatment, they are typically either similar or less severe than prior
    2. Corticosteroids reduce the risk of mild reactions (hives) and respiratory symptoms
    3. Corticosteroids do not reduce the risk of anaphylactoid reactions (albeit rare)
    4. Most significant way to reduce reaction risk is to use nonionic, low-osmolality Contrast Material
    5. Tramer (2006) BMJ 333(7570):675 [PubMed]
    6. Wolf (1991) Invest Radiol 26(5): 404-10 [PubMed]
  3. Corticosteroid protocol (any of the agents below)
    1. Methyl-Prednisolone (Medrol) 40 mg IV at 12 and 2 hours before
    2. Prednisone 50 mg at 13, 7 and 1 hour pre-contrast
    3. Hydrocortisone 200 mg IV every 4 hours
  4. Antihistamines given also, 1 hour pre-contrast
    1. Diphenhydramine 50 mg IV/IM/PO at one hour pre-contrast AND
    2. Also consider H2 Blocker (e.g. Cimetidine, Famotidine or Ranitidine) 1 hour pre-contrast

IX. References

  1. LoVecchio (2023) Crit Dec Emerg Med 37(7): 32
  2. Swaminathan and Rezaie in Herbert (2014) EM:Rap 14(10): 1-2
  3. Maddox (2002) Am Fam Physician 66(7):1229-34 [PubMed]
  4. Greenberger (1991) J Allergy Clin Immunol 87:867-72 [PubMed]
  5. Rawson (2013) Am Fam Physician 88(5):312-6 [PubMed]

Images: Related links to external sites (from Bing)

These images are a random sampling from a Bing search on the term "CT Intravenous Contrast." Click on the image (or right click) to open the source website in a new browser window. Search Bing for all related images

Related Studies

Ontology: Iopamidol (C0022026)

Definition (NCI) An organic iodine compound and used as a non-ionic water soluble radiographic contrast medium. Iopamidol blocks x-rays as they pass through the body, thereby allowing body structures not containing iodine to be visualized. The degree of opacity produced by iopamidol is directly proportional to the total amount of the iodinated contrast agent in the path of the x-rays. The visualization of body structures is dependent upon the distribution and elimination of iopamidol. (NCI05)
Definition (MSH) A non-ionic, water-soluble contrast agent which is used in myelography, arthrography, nephroangiography, arteriography, and other radiological procedures.
Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109) , Pharmacologic Substance (T121)
MSH D007479
SnomedCT 109219007, 395754005
English Jopamidol, 1,3-Benzenedicarboxamide, N,N'-bis(2-hydroxy-1-(hydroxymethyl)ethyl)-5-((2-hydroxy-1-oxopropyl)amino)-2,4,6-triiodo-, iopamidol, (S)-N,N'-bis(2-Hydroxy-1-(hydroxymethyl)ethyl)-2,4,6-triiodo-5-lactamidoisophthalamide, Iopamidol [Chemical/Ingredient], Iopamidol, IOPAMIDOL, Iopamidol (product), Iopamidol (substance)
Swedish Jopamidol
Czech jopamidol
Finnish Jopamidoli
Russian IOPAMIDOL, ИОПАМИДОЛ
Japanese イオパミドール
Spanish iopamidol (sustancia), iopamidol (producto), iopamidol, yopamidol (producto), yopamidol (sustancia), yopamidol, Yopamidol
Polish Jopamidol
French Iopamidol
German Iodpamidol
Italian Iopamidolo
Portuguese Iopamidol
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: iodixanol (C0063757)

Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109)
MSH C044834
SnomedCT 353962003, 395750001
English iodixanol, iodixanol (as iodine), iodixanol (procedure), iodixanol [Chemical/Ingredient], 1,3-Benzenedicarboxamide, 5,5'-((2-hydroxy-1,3-propanediyl)bis(acetylimino))bis(N,N'-bis(2,3-dihydroxypropyl)-2,4,6-triiodo)-, (16alpha)-, 5,5'-((2-Hydroxytrimethylene)bis(acetylimino))bis(N,N'-bis(2,3-dihydroxypropyl)-2,4,6-triiodoisophthalamide), 2-5410-3A, Iodixanol, Iodixanol (product), Iodixanol (substance), IODIXANOL
Spanish iodixanol (producto), iodixanol (sustancia), iodixanol
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: iopromide (C0063817)

Definition (NCI) A contrast medium.
Concepts Organic Chemical (T109) , Indicator, Reagent, or Diagnostic Aid (T130)
MSH C038192
SnomedCT 353903006, 395756007
English iopromide, N,N'-bis(2,3-dihydroxypropyl)-2,4,6-triiodo-5-(2-methoxyacetamido)-N-methylisophthalamide, iopromid, iopromide (as iodine), IOPROMIDE, iopromide (procedure), iopromide [Chemical/Ingredient], lopromid, Iopromide, Iopromide (product), Iopromide (substance)
Spanish iopromida (producto), iopromida (sustancia), iopromida
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: ioversol (C0063828)

Concepts Indicator, Reagent, or Diagnostic Aid (T130)
MSH C054871
SnomedCT 407965009, 356277008, 109222009, 395759000
English ioversol, ioversol (procedure), ioversol [Chemical/Ingredient], Ioversol, Ioversol (product), Ioversol (substance), IOVERSOL
Spanish ioversol (producto), ioversol (sustancia), ioversol
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Visipaque (C0377786)

Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109)
MSH C044834
English Visipaque, Amersham brand of iodixanol, Nycomed brand of iodixanol, Visipaque Unique Softpac
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Contrast media allergy (C0570562)

Concepts Pathologic Function (T046)
SnomedCT 293637006
Dutch contrastmiddelallergie
French Allergie au produit de contraste
German Kontrastmittelallergie
Italian Allergia a mezzo di contrasto
Portuguese Alergia ao meio de contraste
Spanish Alergia a medio de contraste, alergia a medio de contraste (trastorno), alergia a medio de contraste
Japanese ｿﾞｳｴｲｻﾞｲｱﾚﾙｷﾞｰ, 造影剤アレルギー
Czech Alergie na kontrastní látku
Hungarian Kontrasztanyag allergia
English Contrast media allergy, Contrast media allergy (disorder)
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Optiray (C0593051)

Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109)
MSH C054871
English optiray, Optiray, Mallinckrodt brand of ioversol, Tyco brand of ioversol
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Ultravist (C0728741)

Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109)
MSH C038192
English Ultravist, Berlex brand of iopromide, Schering brand of iopromide
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Isovue (C0729210)

Concepts Indicator, Reagent, or Diagnostic Aid (T130) , Organic Chemical (T109)
MSH D007479
English isovue, Isovue
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Contrast media reaction (C0853800)

Concepts Disease or Syndrome (T047)
Japanese 造影剤反応, ｿﾞｳｴｲｻﾞｲﾊﾝﾉｳ
Italian Reazione a mezzo di contrasto
Czech Reakce na podání kontrastní látky
English Contrast media reaction, contrast media reactions, contrast media reaction
Hungarian Kontrasztanyag reakció
Portuguese Reacção a meios de constraste
Spanish Reacción al medio de contraste
Dutch contrastvloeistofreactie
French Réaction à un produit de contraste
German Kontrastmittelreaktion
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: iodinated contrast dye (C0879373)

Definition (NCI) A contrast agent containing an iodine-based dye used in many diagnostic imaging examinations, including computed tomography, angiography, and myelography.
Concepts Indicator, Reagent, or Diagnostic Aid (T130)
English Iodinated Contrast Agent, Iodine-containing Contrast Media, Iodinated Contrast Dye, contrast dye, iodinated, iodinated contrast dye
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: Anaphylactoid reaction to radiocontrast media (C1304190)

Concepts Pathologic Function (T046)
SnomedCT 402396002
English Anaphylactoid reaction to radiocontrast media (disorder), Anaphylactoid reaction to radiocontrast media
Spanish reacción anafilactoide a un medio de radiocontraste (trastorno), reacción anafilactoide a un medio de radiocontraste
Derived from the NIH UMLS (Unified Medical Language System)

Ontology: NON-IONIC CONTRAST MEDIA (C1875544)

Concepts Indicator, Reagent, or Diagnostic Aid (T130)
English NON-IONIC CONTRAST MEDIA, [DX101] NON-IONIC CONTRAST MEDIA
Derived from the NIH UMLS (Unified Medical Language System)

Related Topics in Pharmacology

advertisement

2025 Family Practice Notebook, LLC. Terms | Privacy | About | Site Map | Newsletter | Blog

Footer Site Logo