Contrast Media/Radiopharmaceutical Test 3 Review

What procedures use barium

- esophagus/Esophagram

- stomach/UGI

- small Intestine/SBFT

- large Intestine/BE

What special considerations need to be given when using contrast media in children

- susceptible to fluid shifts (can lead to cardiac failure/pulmonary edema)

- viscosity is also an issue (injection rate/size of catheter/viscosity)

- small volumes, small-gauge angiocatheters and unusual vascular access

What type of contrast media has a low atomic number

- radiolucent (negative)

- produce areas of increased IR exposure (black)

What is the normal range for creatinine levels that is considered to be safe

0.5 to 1.4

Name the contrast used when performing a double-contrast barium enema exam

barium sulfate and air

How is water-soluble iodinated contrast eliminated from the body

excreted through the kidneys

What category of adverse reaction to iodine contrast media requires observation, but usually no treatment

mild

What can be done to reduce or eliminate allergic effects to iodinated contrast media

patient can be pre-medicated with steroids and antihistamines

What type of contrast has anions and cations

water-soluble iodinated contrast media (ionic)

What type of allergic reaction is isolated chest pain related to

moderate

How is contrast administered for a cystogram

through a urinary catheter

What can be done to lower the viscosity of iodinated contrast media

heat to body temperature (contrast warmer)

What is the advantage of using non-ionic contrast media (LOCM) over ionic contrast media (HOCM)

- less chance of a reaction

- greater effects and adverse reactions with higher osmolality

Define osmolality

- the number of particles in a given volume of solution

- most important factor in determining patient discomfort and vasodilation

Name all positive contrast medias

- oil-based iodine contrast media

- barium sulfate

- water-soluble iodinated

What is a normal glomerular filtration rate (GFR) level

60 to 120 ml/min

Name the cations in water-soluble iodine contrast media

the cations part of the molecule is either a sodium atom or a more complex structure, methyglucamine (also called meglumine)

What contrast is used for an UGI exam

barium sulfate

What acute reactions require the use of Epinephrine

- hives

- diffuse erythema

- bronchospasm

- laryngeal edema

- hypotension (with tachycardia)

- hypertensive crisis

What flow rate can a tech set within their scope of practice when administering oxygen during a contrast reaction

6-10 L/min

How can higher-osmolality contrast media (HOCM) effect the kidneys

- osmotic effects

-cause arterial expansion which causes the release of vasoconstrictors (constricts renal arteries) which diminishes blood supply

- osmotic diuresis

- renal tubes cannot reabsorb some molecular substances (dehydration)

Several specific diseases you should screen for increased risk with water-soluble iodinated contrast

- asthma

- CAD

- renal disease

- sickle cell

- diabetes

- allergies

- hypertension

- multiple myeloma

- COPD

What contrast media has a high atomic number

radiopaque (positive)

What is the risk of performing a BE on a patient who has diverticulitis or ulcerative colitis

possible colon perforation

Types of contrast used for a double-contrast arthrogram

- water-soluble iodinated media

- air

The physical properties of barium sulfate

- atomic #56

- compound

- particles in suspension

- chemically inert powder

- substances added

- insoluble

What type of acute reaction to contrast media is facial edema without dyspnea

moderate

What type of acute reaction to contrast media is nasal congestion

mild

True or false

Non-ionic contrast media does not have iodine

false

What treatment is needed for a severe reaction to contrast media

- prompt recognition

- aggressive treatment

- hospitalization

What is viscosity

- influenced by concentration and size of the molecule

- how thick and stick it it. These types are more difficult to inject, produce more heat and vessel irritation

- produces resistance (friction) due to the attraction of molecules to each other during the injection

- contributes to the displeasure some patients experience during injection

Name 3 drugs that can cause interaction with iodinated media and identify what problems can result

patients on hypertension drugs (beta-adrenergic blockers)

- have ab increased risk of anaphylactoid reactions

patients on calcium-channel blockers

- risk of heart block & abrupt decrease in BP

metformin (Glucophage)

- could cause lactic acidosis

Patients with what disease could end up in renal failure from a contrast media injection

multiple myeloma

- cancer in plasma cells (bone marrow)

What adverse reactions can occur with radiolucent (negative) contrast media

- usually minimal

- can cause air emboli (pain and loss of oxygen to area)

What treatment is needed for a moderate reaction to contrast media

- prompt treatment

- close and careful observation (possible progression)

Most ionic contrast media are referred to as

Higher-Osmolality Contrast Media (HOCM) because of their osmotic effects on the body

For what type of reaction to contrast media would a patient be given benadryl

urticaria (hives)

What type of acute reaction to contrast media causes protracted nausea/vomiting

moderate

What is the Amin advantage of using non-ionic contrast media (LOCM)

-less chance of reaction

- are more water-soluble

- lower osmolality levels (results in less- no side effects)

What type of acute reaction to contrast media causes transient flushing/warmth/chills

mild

In what order should the following exams be ordered? UGI, IVP, Acute and series, BE

- acute and series

- IVP

- BE

- UGI

What type of contrast is used if the patient has a suspected bowel obstruction

water-soluble iodinated (gastrogafin)

What is the purpose of using contrast media

- changes the absorption characteristics of the anatomic area (alters subject contrast/IR exposure differences)

- the ability to distinguish between IR exposure levels enables differences in anatomic tissues to be seen (improves visualization of detail)

If your patient has a history of coronary artery disease, acute reactions to contrast media can cause

- tachycardia

- hypertension

- bradycardia

Non-ionic contrast media ____ dissociates into cations and anions and ____ contain iodine

- doesn't

- does

What considerations are needed for patients on hypertension drugs (beta-adrenergic blockers) when using contrast media

have an increased risk of anaphylactoid reactions

What considerations are needed for patients on calcium-channel blockers when using contrast media

• risk of heart block

• abrupt decrease in BP

What considerations are needed for patients on metformin (glucophage) when using contrast media

- uses for non-insulin dependent diabetes

- should be discontinued 48 hrs before & after contrast

- could cause lactic acidosis

Normal BUN levels

7.0 - 25

what is extravasation

leakage through a duct or vessel

Ionic media dissociate into 2 molecular particles. What particles are they and their charge?

Anion - negative

Cation - postive

charge of an anion

negative

charge of a cation

positive

Positive contrast media (radiopaque) are administered as what? Atomic number?

High Atomic Number

Barium

Oil based iodine

water soluble iodine

Radiolucent or Negative contrast agents are composed of what? Atomic number?

low atomic number
Gas, air, gas-producing tablets, crystals, soda water/carbon dioxide

does higher osmolality (ionic contrast) result in more or less reactions to contrast?

more
higher concentration = greater viscosity and greater potential toxicity

____ is the most important factor in determining patient discomfort and vasodilation

osmolality

____ is when barium sulfate contrast media clumps and comes out of suspension

flocculation

does lower osmolality (non-ionic contrast) result in more or less reactions to contrast

lower Risk

low osmolality

Radiopaque positive contrast

has high atomic numbers

absorb xray photons = appear light (decreased density) on image

allergic reactions are caused by what

histamines and anxiety

Osmosis is when water moves from what concentrations?

high to low

instilling contrast medium into anatomic areas of interest is classified as low subject contrast because

low density differences and are difficult to see

to change the absorption characteristics of anatomic areas

alter subject contrast and densities

improves visualization of anatomic detail.