Lab Quiz 7 & 8: Contrast Media Medical Emergencies & Contrast Media Choices (Patient Care Rad 113)

What are barium and iodine contrast agents used for?

They enhance images by making abnormal conditions more visible on x-ray studies.

How is IV contrast filtered from the body?

It is filtered out by the kidneys, with 90% or more eliminated in an hour.

What type of contrast is used in MR scans?

Gadolinium.

What is used in ultrasound imaging?

Microbubbles.

In what forms can barium sulfate be administered?

Powder, liquid, paste, or tablet, and is only used for GI imaging.

What type of contrast agents are always iodine-based?

IV contrast agents.

Is barium used for IV or intrathecal administration?

No, barium is NEVER used for IV or intrathecal administration.

What do positive contrast agents do to x-rays?

They stop x-rays.

What types of administration can iodine-based contrast be used for?

Oral, rectal, intrathecal, transurethral, intra-articular, or IV.

What type of contrast agents are always iodine-based?

IV contrast agents.

Is barium used for IV or intrathecal administration?

No, barium is NEVER used for IV or intrathecal.

What are radiopaque agents?

Substances like barium and iodine that absorb more x-rays than body tissue.

What element is used to enhance MRI images?

Gadolinium

What may be used as contrast agents for some exams?

Saline and gas (air)

What is a negative contrast agent?

Air and CO2

What contrast agents are used in ultrasound?

Saline and air, which form microbubbles or microspheres.

Is air routinely injected in veins or arteries?

No, air is not routinely injected in veins or arteries.

Ionic Contrast

Iodinated sodium or meglumine diatrizoate, such as Hypaque, Conray, and Urografin.

Ionic Contrast Dissociation

Dissociates into positive (cation) and negative (anion) ions in a solution.

High-osmolar contrast media (HOCM)

Increases risk of adverse (allergic) reactions.

Ionic Contrast Side Effects

Includes warmth, flushing, metallic taste, nausea, urticaria, nephrotoxicity.

Ionic Contrast Usage

Limited use; replaced by nonionic agents; used for urinary, gastrointestinal, and angiogram studies.

Ionic Contrast Radiopacity

Excellent radiopacity.

Ionic Contrast Cost

Cheaper cost.

Nonionic Contrast

Iodinated agents such as Omnipaque, Isovue, Visipaque.

Nonionic Contrast Dissociation

Does not dissociate.

Low-osmolar contrast media (LOCM)

Reduced risk of adverse (allergic) reactions.

Nonionic Contrast Side Effects

Less warmth, flushing, metallic taste, nausea, urticaria, nephrotoxicity.

Nonionic Contrast Usage

Commonly used; replaces ionic agents; used for urinary, gastrointestinal, and angiogram studies.

Nonionic Contrast Pre-medication

Used for pre-medicated patients and those with prior reactions.

Nonionic Contrast Cost

Higher cost.

What should be reviewed before contrast injection?

The patient's history, specifically any prior contrast injections.

What are the normal creatinine levels for lab work?

Creatinine levels should be between 0.6 to 1.5 mg/dL.

What is the minimum GFR for adults?

The minimum GFR for adults should be 60 mL/min or greater.

What is the normal BUN level?

The normal BUN level is between 8 to 25 mg/100mL.

What medication should be checked for patients with Type II diabetes before contrast injection?

Any Metformin products should be checked.

What equipment should be checked before contrast injection?

The emergency crash cart and drugs box should be checked (CPR (board), oxygen, suction, monitor, defibrillator, blood pressure equipment.)

What must be available before any contrast injection?

A physician must be available or present.

What may high-risk patients need before contrast procedures?

High-risk patients may need to be premedicated.

What medications are typically ordered for premedication?

Antihistamines like Benadryl and corticosteroids like prednisone are typically ordered.

How long before the procedure should premedication be administered?

Premedication should be administered over a period of 12 to 24 hours before the procedure.

*Note from lecture*

-Prednisone given 12-24 hours before procedure

-Benadryl is typically given right before (30 minutes) procedure

-Epinephrine is given for severe reactions -> immediate action (if Benadryl isn't effective)

Where should patients be scheduled for contrast procedures if possible?

Patients should be scheduled at a hospital with a fully stocked emergency room.

What are contrast agents?

Contrast agents are substances used in medical imaging to enhance the contrast of structures or fluids within the body.

How are contrast agents classified?

Contrast agents are generally classified as Positive or Negative.

What is Barium in radiographic contrast?

Barium is a positive contrast agent with an atomic number of 56, commonly used in imaging the gastrointestinal tract.

What is Iodine in radiographic contrast?

Iodine is a positive contrast agent with an atomic number of 53, frequently used in various imaging studies, including CT scans.

What is the atomic number of Air/gas?

Air/gas has an average atomic number of 8 and is used as a negative contrast agent to create differences in density in imaging.

What is Carbon dioxide used for in radiographic imaging?

Carbon dioxide is used as a negative contrast agent, particularly in certain types of imaging procedures.

What is Room air in radiographic imaging?

Room air is considered a negative contrast agent, providing a baseline for comparison in imaging studies.

What should be ensured regarding the administration of contrast?

The administration of contrast should be appropriate for the patient.

What should be balanced when considering a contrast exam?

The possibility of an adverse event should be balanced with the benefit of the exam.

What is promoted through the use of contrast in exams?

Efficient and accurate diagnosis and treatment.

What should be prepared for in case of a reaction to contrast?

Be prepared to treat a reaction should one occur.

What is important to obtain regarding the patient's history?

Obtaining adequate history considering the risks and benefits of using or avoiding contrast.

What premedication may be considered for patients with previous reactions?

Premedication with corticosteroids and antihistamines may be considered.

What should be ensured regarding patient hydration?

Ensure the patient is well hydrated before and after the procedure.

What is advised regarding contrast use in pregnant or lactating women?

Contrast should be avoided unless absolutely necessary, as determined by the ordering physician or radiologist.

What do manufacturers suggest for breastfeeding mothers after contrast injection?

Manufacturers suggest that concerned mothers suspend breastfeeding for 24 hours after the contrast injection and actively express and discard breast milk for that period.

What should be done with breast milk before a contrast exam?

It is advised to store breast milk before the exam.

Informed Consent

Explain procedure and obtain informed consent (review history)

Possible Side Effects

Inform about possible side effects (warm sensation, metallic taste), nausea.

IV Access

Establish IV access (preferably) large-bore cannula.

Crash Cart

Ensure (crash cart) is fully stocked and available.

Patient Monitoring

Monitor patient (during and after) the procedure for extravasation or delayed reactions.

Post-Contrast Hydration

Encourage oral or IV (hydration) after the procedure.

Observation for Reactions

Observe for immediate or delayed reactions (rash, dyspnea) up to 24 hours.

Renal Function Reevaluation

Physicians may reevaluate (renal function) 48-72 hours after contrast in high-risk patients.

Prior allergic-like reaction

The greatest risk for predicting future adverse events.

Allergic to iodine

Increases the likelihood of an allergic-like reaction.

Hx of Asthma

A risk factor for allergic-like reactions.

Dehydration

A condition that increases the likelihood of an allergic-like reaction.

Diabetes (type I and type II)

A risk factor for adverse events related to contrast media.

Renal status (acute)

Sudden reduction in kidney function.

Renal failure (chronic)

Long-term condition where kidneys can't filter blood properly.

Sickle-cell disease

A condition that increases the risk of adverse events.

What should patients do before and after any contrast procedure?

Increase fluid intake.

What should be monitored in high-risk patients undergoing contrast procedures?

Renal function.

What may happen to barium in the GI tract?

It may solidify and be difficult to pass.

What is suggested for patients to help pass barium?

Drink plenty of water and sometimes use a mild laxative.

What does increased fluid intake help with after iodinated contrast?

It helps the kidneys flush out the contrast.

What type of compress should be used for IV contrast extravasation?

Warm or cold compress.

What condition should be watched for that may lead to tissue necrosis and ulcerations?

Compartment syndrome.

What is the iodine concentration of Isovue 200?

200 mg iodine/mL

What is the iodine concentration of Isovue 300?

300 mg iodine/mL

When is Isovue 200 typically used?

For intrathecal use, children, and high-risk patients.

What is the advantage of Isovue 300?

Better visualization and enhancement of organs, blood vessels, and structures.

What do both Isovue 200 and 300 contain?

Iodine, making them radiopaque agents.

How does higher concentration of Isovue improve CT scans?

It improves visibility of structures on scans.

Patient history

A consideration in determining the use of contrast.

Renal function

An important factor in assessing the safety of contrast use.

BUN

Blood Urea Nitrogen, normal range 8 to 20 mg/dL.

Creatinine adult

Normal range 0.6 to 1.5 mg/dL; more sensitive predictor of kidney function.

SeCr above 1.5 and GFR below 60

Indicates possible Renal Insufficiency; contrast should not be used if average range is below 30.

Contrast-enhanced CT or GI studies

Methods of amplifying the visible difference between adjacent structures on imaging by administering contrast media/agents.

Types of contrast available

IV, PO, Intrathecal, intraarticular, transurethral, and rectal.

Gadolinium

Used for MRI procedures.

Iodinated contrast

Used for Radiography procedures.

Average dose

(.5 mL) per pound.

Purpose of contrast media

Enhance the visibility of (internal) structures.

Sensitivity in children

Children have a (higher sensitivity) to adverse effects compared to adults.