CAT SCAN REGISTRY - Medications and contrast

Medication reconciliation

the process of reviewing the patient's medication record at all points of care, including admission, transfer of service (i.e., imaging procedures), and discharge.

Coumadin (warfarin)

An anticoagulant. This drug is used to prevent the formation of blood clots in veins and arteries and may reduce the incidence of heart attack and stroke.

Metformin (glucophage)

A drug used to treat type 2 diabetes

Precaution for Metformin use

Patients with acute kidney injury or severe chronic kidney disease should avoid this drug before and up to 2 days after receiving iodinated contrast media (ICM) due to the risk of renal impairment.

Anxiolytic medication

Medications prescribed to reduce anxiety, often used before medical imaging procedures like CT examinations.

Benzodiazepines

A class of anxiolytic drugs that includes diazepam (Valium), alprazolam (Xanax), clonazepam (Klonopin), and lorazepam (Ativan).

Selective serotonin reuptake inhibitors (SSRIs)

A group of medications that may include paroxetine (Paxil), sertraline (Zoloft), fluoxetine (Prozac), and escitalopram (Lexapro), used to reduce anxiety.

Degree of radiopacity of Iodinated and Barium Contrast Agents (Radiopaque Contrast Media - RCM)

Directionally proportional to the concentration of the agents

Iodinated RCM

A water-soluble compound that may be administered: Generally into the bloodstream via IV, directly into a targeted vein or artery for localized enhancement, directly into the intrathecal space during CT myelography, into the joint space during CT arthrography and orally to opacify the GI tract.

Barium Sulfate Suspensions

Suspensions of barium sulfate are commonly employed as positive contrast agents for opacification of the GI tract.

Osmolality

describes the intervascular RCM agent's propensity to cause fluid from outside the blood vessel (extravascular space) to move into the bloodstream (intravascular space).

Intravascular Radiopaque Contrast Media

Contrast agents used for vascular CT cases. Used iodinated RCM

Iodinated RCM can be generally divided into 2 categories

Ionic contrast media and Nonionic contrast media

Ionic contrast media

Contains salts consisting of sodium and/or meglumine. Each molecule of ionic contrast agent consists of three iodine atoms. When injected into the bloodstream, each molecule dissociates into two charged particles, or osmotic ions. This contrast media is considered high-osmolar contrast media (HOCM)

Nonionic contrast media

Contains nonsalt chemical compounds that also contain three atoms of iodine per molecule. They do not dissociate in solution. These substances are commonly referred to as low-osmolar contrast media (LOCM).

Osmolality of the contrast medium

Greatly affects its potential for adverse effects in the patient. Nonionic low-osmolar contrast agents are less likely to produce adverse side effects and/or reactions than ionic high-osmolar RCM.

Iso-osmolar contrast media (IOCM)

A type of contrast that have the same osmolality as blood and therefore may offer improved patient comfort and a reduced potential for untoward side effects.

Enteral Radiopaque Contrast Media

Contrasts used for GI cases, administered either orally or rectally. Its either a water-soluble iodinated solution or a suspension of barium sulfate.

Barium sulfate and water soluble iodinated contrast agents routine transit time through the GI tract

Between 30 and 90 minutes.

Barium Sulfate considerations

May be not be utilized in cases of suspected perforation because it may be toxic to the peritoneum.

Is also contraindicated in patients who are to undergo surgery or other invasive procedures of the abdomen and/or pelvis.

Can be potentially harmful if aspirated.

Water-soluble oral contrast agent considerations

Are usually more palatable and result in less GI distress.

May be contraindicated in patients with known iodine allergy.

Negative Contrast agents

Air, gas and water

Advantages of water as a GI contrast agent

Increased palatability and improved patient comfort.

Better demonstration of the enhancing bowel wall.

Does not interfere with three-dimensional (3-D) applications

Air as a contrast utilization

GI and chest scans

Neutral Contrast Agents

Used to opacify the small bowel during procedures such as CT enteroclysis and CT enterography. Very low-density (0.1%) barium sulfate solutions are used.

diphenhydramine HCl (Benadryl) and a corticosteroid (prednisone or methylprednisone)

Antihistamine and steroid combo taken at timed intervals beginning as early as 12 to 24 hours before contrast agent injection. This is a pretreatment of patients who are at increased risk for adverse reaction to iodinated contrast agents.

Breakthrough Reaction

A repeat adverse reaction to iodinated contrast material in the patient who has undergone a pretreatment regimen. Patients who develop this are at greater risk for moderate or severe allergic reactions during subsequent administration of iodinated contrast material.

Contraindications to IV iodinated contrast

Allergy to iodine.

Prior severe allergic reaction to an iodinated contrast agent.

Renal insufficiency/failure.