contrast and medicine in imaging Flashcards
(43 cards)
what 3 reasons for using contrast
- differentiate anatomy
- differentiate patholofy
- provides info on function
what are the 2 categories of contrast and give examples
positive (bright on CT) E.G iodinated/IV administrated
negative (dark on ct) e.g gas, water
osomolality
high ormolu (ionic)
low osmolar (non ionic monomer)
iso osmolar (non ionic dimer)
3 main risks with contrast
- extravasation (leaking out of vein)
- allergic reaction
- acute kidney injury
what are the 3 types of fixed timings with contrast
arterial
portal venous
delayed phases
gadolinium is used in MRI, this is toxic. why and how is it excreted from the bodu
toxic as it completes with Ca2+
- cant be excreted so it binds to other molecules to be excreted
linear agents are restricted for usage due to what disorder it causes
nephrogenic systemic fibrosis (fibrosis of skin, joints etc)
what is the mechanism of gadolinium and how does this affect the way it looks on images
- shortens t1 decay (increase image brightness in t1w)
- shortens t2 ( limited/no use in t2w)
if theres too much gadolinium, what happens to signal
t2 properties overwhelm t1 properties and signal is lost
radiographer are part of PGD, what is this
patient group directive
- legal framework allowing certain registered health professionals to supply or administer certain meds to a PRE DEFINED GROUP of patients without needed to see prescriber
what is PSD
patient specific directive
- group prescription (symptoms within a scope can be given this drug)
what are the 2 main routes of drug prescribing
oral
IV (syring or pump)
what is an analgesia
analgesic drug, also called simply an analgesic, antalgic, pain reliever, or painkiller, is any member of the group of drugs used for pain management.
what range of sedation can be given to patients (what is the most commonly used)
anxiolytic (reduced anxiety) to general aesthetic (not routine)
what drug is commonly used as local anaesthesia
lidocaine
- injected in skin surface deeper structures
- often used for biopsy sites or dental anaesthesia
lidocaine can also be used for what medical symptom, thus isnt injected via vessels
cardiac arrythmia
what can lidocaine be combined with to prolong action via vasocontriction
adrenaline/epinephrine
for CT guided biopsy:
- local anaesthetic in skin surface and deeper tissue
- sedation may be needed if hard procedure or patient extra anxious
- systemic analgesia f painful after
what are the opioids and non-opioids are given as a form of systemic analgesia (pain killer)
opioids : fentanyl
non-opioids: NSAIDS, paracetamol, entonox
benzodiazepine is a class of medications that slow down activity in your brain and nervous system, which form of this is most commonly given in imaging
midazolam
(anxiolytic (anxiety relief) and amnesic properties)
remember that sedatives such as midazolam cannot be given by radiographer, this must be prescribed by proper staff e.g doctor or sedation team
what is 2 most common general anaesthetic prescribed
propofol (only administered by anaesthetic team)
ketamine (again only given by dedicated team or experienced individual)
sodium pico sulphate is a chemical compenent given to clear bowls, what are the 3 types that can be given
- picolax
- citrafleet
- citramag
how do sodium picosulfate work and what do u use it for
stimulant laxative
- clear faecal residue before colonic investigation
