Positioning Aids

Question 1

What are the key properties of positioning aids?

Answer 1

adaptable
easy to clean/low maintenance
made from radiolucent material

Question 2

troughs

how are they used? are there any considerations to make?

Answer 2

rigid plastic or foam-based

ideal for ventral-dorsal images

come in a range of sizes
- but not very adaptable
- need many = lots of storage

considerations
- lifts the patient slightly above the plate creating an air gap
- head hangs off - if not supported increased pressure of diaphragm, hypotension likely, pressure on ETT and arrhythmias may occur

Question 3

sandbags and foam wedges

how are they used? are there any considerations to make?

Answer 3

commonly used to prevent rotation and maintain straight line supporting concave structures (eg, head/neck, hips)

considerations
- sandbags are radiopaque
- foam wedges are radiolucent
- sandbags are good for holding ties instead of tying to table

Question 4

ties and straps

how are they used? are there any considerations to make?

Answer 4

only use when patient is under GA
- so can’t hurt themselves
- unlikely to suddenly wake up

allow you to straighten limbs in line or keep other limbs out of the way
- less resistance from pain/discomfort
- however can cause more damage/pain to patient when awake

Question 5

what are the types of patent restraint for x-ray positioning?

Answer 5

manual
physical
chemical

Question 6

what is manual restraint?

Answer 6

physically holding/restraining patient ourselves
- should only be done in emergency situations
- unsure if patient will manage chemical restraint

handler must:
- wear PPE and dosimeter
- not have any part of body within primary beam

Question 7

what is physical restraint?

Answer 7

the use of equipment to restrain
- cant use chemical and manual would cause too much stress/injury or too dangerous

cats/dogs - wedges, ties, troughs etc

exotics - radiolucent container/tubing
- limits their movement

some reptiles - vasovagal reflex
- pressure and cover eyes to keep still

Question 8

what is chemical restraint?

what are its benefits?

Answer 8

preferred method - use of sedation/GA

provides a better image quality
- allows better positioning
- less resistance from pain/discomfort
- however can cause more damage/pain to patient when awake

likely to position correctly first time
- no repeat exposures

no movement artefacts will occur
- don’t need high speed x-ray (quickly before moving)
- so less energy for scatter

Question 9

what considerations need to be made for neonates?

Answer 9

bone density
- think about growth plate development
- know whats premature or abnormal
- can easily overexpose young bones -

development stage
- both age and species
- precocial - more developed at birth
- altricial - less developed at birth

restraint
- fragile when young
- reduce as much time as possible so smell less like us - mother may reject/stress

Question 10

what considerations need to be made when imaging exotics?

Answer 10

bone density varies between species

restraint
- can be challenging
- reduce as much as possible
- often very delicate
- may not be used to handling
- often wild - be quick/prepped as highly stressed
- DON’T HOLD LIZARD TAILS!!

equipment
- should be easily cleaned - carry diseases
- tubing, towels, blocks, containers
- if using tubing make sure cant roll
- repurpose bandaging rolls or toilet roll holders as can be safely disposed of