CM Flashcards
w/v
higher w/v means its a thicker solution
Oil-based CM…
oil-based CM takes longer to be absorbed by the body
High osmolar
HOCM - comes with more edverse effects
Low osmolar
good/safer
Relatioship b/w concentration and toxicity
higher concentration = higher toxicity = higher viscosity
Less adverse reactions when…
- non-ionic
- low osmolality
- low iodine concentration
- slow injection
Poor renal function
- calculate GFR (lower GFR = lower kidney function)
- higher creatinine = lower kidney function
Negative CM
- radiolucent
ex. air, CO2
positive CM
radiopaque
ex. barium, iodine
severe adverse reaction
cardiac or respiratory arrest
shcok/seizures
medium adverse effects
pulse change (bradycardia or tachycardia)
Hypotrnsion/hypeetension
Outline the responsibilities of the technologist during contrast media reactions.
get help
stay with patient
assist with emergency drungs and equipment
ABC’s (Airway, breathing circulation)
list patient conditions that contraindicate the use of any contrast media.
renal failure
diabetic with renal failure
people over 70 years of age
Identify the three groups of contrast by route of administration, naming examples of each.
intravenous (IV) -
intraarterial (IA)
intrathecal -
Viscosity def.
Measure of the resistance of fluid to flow
Determined by number of particles and attraction
High iodine concentrations tend to be more viscous
toxicity def.
Amount at which a drug has a toxic effect on the body
Theraputic index (TI)
osmolarity def.
Measure of moles of solute per litre of solution (mol/L)
- Discuss the advantages and disadvantages of using gastrografin in radiographic studies.
Used in cased of GI perforation and CT
High osmoality causes significayn osmotic action
Dilution, dehydration, electrolyte imbalance
Explain the purpose and characteristics of contrast media.
- Agents are added to increase subject contrast
- It changes the ability of tissues to absorb or transmit radiation
- Used when organ or system is too similar to surrounding area
CM - Small intestine
Barim sulfate
CM - uterus
Oil is preferred
CM - Lymph nodes
oil based if availible
CM - Brain
iodine
CM - spinal cord
Non-ionic iodine
CM - Ureter
non ionic iodine
CM - shoulder joint
Air, Iodine (double contrast)
Barium sulfate (Z = 56)
not absorbed by the body
doesnt alter normal function
forms suspension with water (not water soluble)
taken orally or rectally
used for GI tract
excreted by GI tract
measured in w/v (weight of barium/total volume to equl 100 gm of suspension)
not used if suspected perforation
iodine concentration relationships
higher iodine concentration = higher risk of adverse reactions = brighter on image
IV contrast agents excreted …
via the kindeys
iodinated contrast
- Consist of large molecules with poor lipid solubility
- Don’t cross cellular membrane well
- Primarily distributed in bloodstream
- Administered: enteral, IV, IA, intrathecal, intravaginal, percutaneously into joints
(Can be taken orally (ideal for pts. with possible perforation)
Types: enteral, oil, intravascular
