Specialized Imaging 1 Flashcards
What is medical asepsis? Microbial dibution?
Reducing the probability or infectious organisms being transmitted to a susceptible individual
-the process of reducing the total number of organisms (microbial dilution)
3 levels of microbial dilution
- Simple cleanliness: proper cleaning, dusting, linen handling, hygiene
- Disinfection: destruction of pathogens by using chemicals
- Sterilization: treating items with heat, gas, or chemicals to make the germ free
What is the difference between and Antiseptic and and Disinfectant?
Antiseptic is a substance that INHIBITS the growth and reproduction of microorganisms
Disinfectants ELIMINATE many or all pathogenic microorganisms
What is surgical asepsis?
The complete destruction of all organisms and spored from equipment used to perform patient care procedures
What is sterile conscience?
Awareness of sterile technique and the responsibility for telling the person in charge if contamination has occurred
What is the area between the patient drape and the instrument table called?
Sterile corridor
Health care members on a surgical team include?
- Surgeon
- Surgeon assistant
- Anesthesiologist
- RN
- Radiologic Technologist
Examples of procedures that required imaging
- operative cholangiograms
- urethral retrogrades and stent placements
- orthopedics
- pacemaker insertion
- intravascular trauma
- foreign objects
3 areas of the OR envrionment
- Unrestricted Zone: street clothes, change rooms
- Semi-restricted Zone: scrub clothing, hair, and shoe covers
- Restricted Zone: scrub suit, hair coverings, shoe coverings, mask
What is a sterile field?
A microorganism free area prepared for the use of sterile supplies and equipment
How do sterile indicators work?
They are placed outside or inside the pack to be sterilized. They change colour when proper sterilization has occurred
How long are items sterilized in the hospital and stored in a closed cupboard considered sterile for?
30 days
How long are items sterilized in the hospital and stored in an open cupboard considered sterile for?
21 days
Items seals in plastic bags immediately after sterilization are considered sterile for how long?
6-12 months
Packages are considered sterile if they meet the following criteria:
- clean, dry, and unopened
- expiration date has not exceeded
- sterility indicators have changed to a predetermined colour confirming sterilization
Purpose of the surgical scrub?
To remove as many microorganisms as possible from the skin of the hands and lower arms by mechanical and chemical means
5 Methods of sterilization
- chemical
- dry heat
- convention gas
- gas plasma technology
- autoclaving
Chemical sterilization
Involves the immersion and soaking of objects in a bath of germicidal solution followed by a sterile water rinse
- effectiveness depends on solution strength and temp and immersion time
- used if objects cant go into autoclave or gas
- DOES NOT KILL SPORES
Dry heat sterilization
In an oven
- required to sterilize some sharps, certain powders, and greasy substances
- long time, high heat
Conventional gas sterilization
Items that would be damages by high temps are sterilized by a mixture of gases
- used for electrical, plastic, rubber, optical wear, and items in isolation rooms
- gases are poisonous and must be dissipated (slow process)
Gas plasma sterilization
Safer method of sterilizing heat and moisture safe items
-cannot sterilize instruments that have long, narrow lumina, powders, liquids, or any cellulose materials (cotton, paper, linen)
Autoclaving sterlilzation
Steam under pressure
- most common
- cheap, quick, most convenient
- high temps achieved under pressure
- tap indicators
2 methods of skin preparation
- Mechanical: removal of hair, friction scrub
- Chemical: after mechanical skin prep, skin painted with antiseptic-destroys microbes
REVIEW RULES FOR SURGICAL ASEPSIS (handout)
.
According to OSHA, when a radiographer is assigned to work in the surgical department, what are the protocols? (9)
- Closed heel and toe shoes, not cloth
- Meticulous personal hygiene
- Jewelry, long artificial nails, and nail polish are prohibited
- Body piercing jewelry must be removed
- To enter the semi restricted zone you must don scrub attire in the dressing area, tuck top into pants
- All hair, beards, moustaches must be covered with a surgical cap/mask
- Shoe covers must be worn
- Before preceding into zone 3 (restricted) scrub hands and arms for medical asepsis
- Don a mask before entering room where surgical procedure performed
A mobile c-arm fluoro unit includes what?
- c-arm with x-ray tube and image intensifier
- tv monitors (2)
Features of the mobile C-arm?
- digital imaging and storage
- image hold feature
- image enhancement, masking, and subtraction
Movement of the C-arm?
- In-out lock: front moved back and fourth from base
- Wig-Wag: C-arm waves side to side from base
- Lateral-Parallel: ‘C’ moved from AP to lateral position
- Cephalad-Caudad: angled tube IR up or down the table
- Up and down: raises and lowers ‘C’
What does the brightness control do on the C-arm? Does it affect patient dose?
Brightens or dims the image. Yes, its changes the mA to adjust the brightness
What is it called if an image intensifier has normal, mag 1, and mag 2 mode
Trifield
What controls does the foot pedal for the C-arm have?
- Low dose fluoro
- Vascular footswitch
- High dose fluoro
What does the dose report on the C-arm display show?
- dose
- demographics
- fluoro time
Which c-arm tube position has least exposure to operator?
- tube under table
- I.I above patient
Which c-arm tube position gives the most exposure to operator?
- tube above table
- I.I below patient
When the tube is closer to the operator the dose to them is higher** watch when angling tube**
.
What end should you stand at when the C-arm is in a lateral position?
I.I end
How far away from the tube should you stand?
6 feet
What kind of drapes are there when using a C-arm?
- shower curtain drape: between patient and surgeon
- temporary patient drape: drape over patient
Surgical Radiography procedures?
- ORIF Hip and Femur
- Cardiac pacemaker insertion
- Kidney stone removal
- Cholecystectomy (gall bladder removal)
- Operative cholangiogram (done during cholecystectomy)
- Foreign body localization
With what imaging modalities can we do arthrography?
- fluoro
- CT
- MRI
- sometimes a combo
What kind of asepsis do we use for arthrograms?
Surgical asepsis
What is arthrography?
A method of radiographically visualizing the inside of a synovial joint and related soft tissue structures using contrast medium
What types of contrast do we use for arthrography?
- radiopaque
- radiolucent
- or both, never just air
What happens if fluid is present in the joint during arthrography?
-aspirate the fluid after local anesthesia and before contrast
Patient prep for arthrography?
- no food/drink restrictions
- allergies
- patient gowned based on type of arthrogram
- explanation of procedure
- informed consent signed
Equipment for an arthrogram?
-fluoro
-conventional x-ray tube
Arthrogram tray:
-prep sponge
-fenestrated drape
-syringes
-flexible connector
-needles
-gauze
Clinical indications and contraindications for a knee arthrogram?
-tears in joint capsule
-tears or degenerations of menisci
-ligament injury
Contraindication: hypersensitivity to iodine based contrast media or local anesthetic
General arthrogram procedure: knee
- Site prepared
- Retropatellar, lateral, anterior, or medial approach
- Skin anesthetized
- Fluid aspirated
- Contrast media instilled (5ml positive, 80-100ml negative)
- Needle removed and knee wrapped
- Knee exercised
Hip arthrogram is most often performed to?
- evaluate congenital hip dislocation in children
- detect loose hip prosthesis
- confirm infection in adults, aspirate sent for analysis
- inject steroid, pain relief, or artificial synovial fluid in patients awaiting replacement surgery
What is the most common arthrogram site?
Shoulder
What is a shoulder arthrogram performed to evaluate?
- partial or complete tears in rotator cuff or glenoid labrum
- persistent pain or weakness
- frozen shoulder
- often done in conjunction with MRI, gandolinium injected at the same time
Contrasts used for shoulder arthrograms?
Single: up to 12ml of positive
Double: 2-4ml positive and 10-12ml negatiive
Indications for wrist arthrograms? Procedure?
-trauma
-persistent pain
-limitation of motion
Procedure:
-1.5-4ml of contrast injected into dorsal wrist at articulation of radius, scaphoid, and lunate
-wrist manipulated to disperse contrast
Common projections for wrist arthrography?
- PA
- Lateral
- Both obliques
- fluoro recommended during rotations to detect leaks (lots of little bones)
Pertinent documentation for an arthrogram?
- Consent form
- Fluoro time, images taken
- Contrast and medications used (amounts)
- Injections time
- Any reactions to contrast
- Fill out lab rec if aspirate is being sent to lab
Common areas for pain management exams?
- Hip
- Shoulder
- Spine
- knee
- elbow
- spine
- hand and fingers
Common indications for pain management injections?
- bursitis
- tendonitis, tendonosis, tenosynovitis
- arthritis
- various forms of back pain
Tech’s role during a pain management injection?
- room set up
- set up trays, required equipment, contrast, and medications
- obtain patient consent form
- pre and post patient evaluation and documentation
- operation of c-arm
- look up any previous studies related to procedure
What does a pain management consent form include?
- patient demographics
- type of procedure and performing physician
- general description of procedure and side effects
- checklist for medical history
- area for patient to sign, consenting to procedure
- recent antibiotics, blood thinners, diabetes?
Order of medications used in pain management injections?
- Local anesthetic
- Contrast
- Pain relief
- Steroid (order of these 2 is radiologist preference)
Additional supplies used for pain management injections?
- basic injection tray (3+ syringes, drapes, cleaning sponge)
- metal object (clamp)
- marker to draw dot
- band-aid
- positioning sponges
- cleansing solution for the skin
- gauze
- juice (in case of dizziness)
- well stocked meds and contrast not expired
- emergency drug box in case of allergic reaction
How long must the patient wait after the procedure? Why?
10-30 mins post exam for condition to be evaluated and post injection pain
Common and rare reactions?
Common:
-skin redness, dizziness, fainting, bruising at site, discomfort
Rare:
-infection, allergic reaction, bleeding, freezing of nerve causing temp loss of sensation
What are epidural spinal injections used for?
- contrast injections for CT myelogram
- injection of radionuclide for nuclear medicine scans
- injections of chemo into spinal canal
- injections of steroid or medication for pain managment
At what vertebral level do we usual inject epidurals?
L3-L4
Lumbar puncture procedure
- patient changed into gown, pants off, underwear on
- patient lies prone on a bolster
- towel tucked into underwear and slid down to PSIS
- radiologist fluoros to see condition of spine
- area is prepped with SURGICAL ASEPSIS
- needle is inserted under fluoro
- tech rotated c-arm to lateral
- confirm location of needle and advance into epidural space
- inject contrast to confirm location
- sample of CSF may be taken
- steroid, chemo, or radionuclide is injected
- patient transferred to stretcher to remain for 15-30 mins
Lumbar puncture needle placement and injection process
- Skin prep
- Lumbar puncture
- CSF sample collected
- Contrast medium instilled
- Needle removed
How are patient positioned for facet injections?
RAO or LAO
What is a facet injection?
Injection of a local anesthetic directly into the zygapophyseal joint(s) causing the pain
What is a medial branch block
Freezing the nerves that connect to the facet joints and send pain signal to the brain
What is a way to reduce scatter in obese patients?
Grids: 8:1 or 10:1
Collimation
Proper IR sizes
How can a bariatric patient potentially be more difficult to image?
- body habitus effects quality of image
- can impact equipment: heat capacity, weight limits
- affects radiographer’s ability to transfer/position them safely
- potential injury for radiographer
- “routine” exams take longer
What should you consider when you have a bariatric patient on your table?
Have table as low as it will go and do not float it
How can we transport bariatric patients?
- larger wheelchairs
- special beds/stretchers
- power lifts
How to transfer and move a bariatric patient safely?
- make sure table can support weight
- have adequate personnel to help
- communicate during the transfer
What may be the only landmark available for palpation on a bariatric patient?q
Jugular notch
How can we find the symph by knowing where the jugular notch is?
<5feet: 21 inches or 53cm
5 to 6 feet: 22 inches or 56cm
>6feet: 24 inches or 61cm
The most important adjustment to be made is increasing your ______ (expoosure factor) when imaging bariatrics
kVp
Technical considerations for working effectively with obese patients?
- warm up tube
- use lower mA settings (<320mA)
- use higher kVp settings
- do not make repeat exposure near tube loading limit
- use large focal spot for all but distal limbs
- do not use APR
- when using AEC ensure kVp is high enough and mA is moderate
- collimate to size of IR or smaller
- collimate to suggested field size or smaller with DR
- never collimate to max size of flat panel DR
- maintain special exposure technique chart
- stand at right angles to the central ray when holding obese paitient (not a good idea anyway)
Always assist your elderly patient to….
- Get on and off of the table
- To change position
- To sit down
What must we consider when adjusting our technical factors for geriatric patients?
- loss of bone mass and atrophy = decreased kVp
- use shorter exposure times if they suffer from tremors or are unsteady
Supine AP Abdomen on the elderly: considerations?
- use a radiolucent mattress to provide comfort
- warm blanket
- help patient onto table (lower it as much as possible)
- practice the breathing instructions with them (hard of hearing, or can’t understand)
- watch that they follow directions
Which view do we do if the patient can stand for an upright abdomen?
Lateral decubitus
Upright chest radiography on geriatrics: considerations?
- have them hold onto the chest stand for support
- for lateral can get them to hold onto IV pole if they can’t raise their arms high enough
- raise patient’s chin
- read requisition and adjust technical factors appropriately
Since geriatrics often breath more shallow, what must we do to get entire lung fields?
- CR high (T6/T7)
- utilize second inspiration exposure to ensure deep inspiration
Sitting chest radiography on geriatrics: considerations?
- if no grid is required with CR cassette use a lower kVp and higher mAs
- angle tube to match angle of sternum
- watch patients chin isn’t in the way of anatomy
If geriatric patient cannot flex neck enough for an odontoid view, what can we do?
-Angle our tube
What image should be done first when examining a geritiatric hip trauma?
AP pelvis
Normal changes in vision in a geriatric patient include?
- loss of visual activity
- loss of ability to focus on near objects (farsightedness)
- loss of adaptation from light to dark
- loss of colour perception
- tear production is reduced or increased
Guidelines to assist elderly with vision difficulties
- Speak within patient’s field of vision and maintain eye contact
- Keep room lights on while giving instructions
- Have them sit up if they’re on a stretcher to see the room
- Assist patients on and off footsteps
- Turn room lights off if requested
- Allow patient to wear their glasses if they won’t effect exam
- Offer assistance should they require extra support
- Give patient extra time to move and adapt from light to dark
Normal changes in hearing in geriatrics?
- decreased ability to hear sounds in the high range tone
- sensory, neural, and conductive changes in physiology of the ear
Guidelines to assisting elderly with hearing difficulties?
- Be patient
- Stand in front of the patient and maintain eye contact while speaking
- Talk in a lower tone of voice, carefully, and slowly
- Eliminate background noise
- Repeat instructions if they do not appear to understand, or rephrase it
- Simplify complicated instructions
- Give them time to process information
- Demonstrate instructions
- Practice breathing instructions with patient
Normal changes related to balance and co-ordination in geriatrics?
- decreased muscle strength
- weakened bones
- shortened spinal column
- decreased reflexes
- time needed to perform activities increases
- increased fatigue
- sensitivity to rapid changes in lighting can cause blindness
- vertigo and dizziness from changing positions
- decreased height perception from declining eye sight
Guidelines to assist elderly who have balance/coordination problems
- Offer assistance
- Allow them to use their walking aids and leave them close by
- Ask patient if they need assistance
- Let patient rest a few minutes after sitting up
- Provide handgrips where possible
- Watch that the patient doesn’t hold on to the edge of the table
- Use caution at all times
- Reassure them and provide your attention
Are geriatrics usually more cold or hot?
Cold
Guidelines to assist geriatrics who are cold
- Put a sheet on the x-ray table or use a mattress
- Maintain a sheet over the patient whenever possible and only expose areas that are required
- Offer a warm blanket to the patient post examination
For a stroke patient do we undress the affected or unaffected side first?
Unaffected side first
Normal skin changes for geriatrics?
- becomes lax and wrinkled
- looks pale and more opaque
- becomes thin and fragile
Guidelines for working with elderly patients: skin/soft tissue changes?
- Be more aware of patient’s skin when transferring
- Reduce risk of decubitus ulcers by using mattresses pads or sponges
- Never try to pull on a patient’s arm to try to help them up
Normal lung/respiratory changes in geriatrics?
- compromised cough reflex
- compromised respiratory reflex
- decreased pulmonary function and stiffening of the chest wall
Guidelines when working with geriatrics: lung/respiratory change
- Practice breathing instructions with patients prior to exposure
- Supine positioning is preferred over prone (on table)
- If patient is supine, build their head up with pillows for easier breathing
- Allow patient time to catch their breath between positions
- Be aware of patient condition and check in with them throughout the exam
What is the most common cause of heart disease in the elderly? How should we adjust out technique?
Arteriosclerotic heart disease
-increased in mAs and kVp to visualize heart border because of fluid build up and pulmonary edema
How should we adjust out technique for pneumonia?
Increase mA to provide density to the radiograph without over penetrating fine lung marking
-good inspiration very important to fully aerate the bronchioles
How should we adjust our technical factors for aspiration pneumonia?
Increase
What can easily occur in elderly patients during a swallowing examination?
Aspiration
Causes of osteoporosis and aging women? How does osteoporosis affect our technical factors?
- decrease of estrogen
- lack of exercise
- lack of calcium
- decreased kVp (lowest possible)
How should be adjust our technical factors to enhance contrast on a fracture on a geriatric patient?
- lower kVp
- increase mA
What is Paget’s disease? How should we adjust our technical factors?
Abnormal bone modeling, bowing of long bones, soft bone
- larger image receptors may be required (bowed bones, larger bones)
- increase kVp to compensate for increased calcium content
How does diabetes mellitus affect imaging of the foot?
Use graduate filter under the foot helps to improve contrast when exposure factors must penetrate the tarsal bones.
What are contractures? What are they caused by? What can we do?
Neuromuscular diseases, CVAs, trauma, and burns can result in abnormal muscle tone, if the tone increases then the spasticity ensues, leaving the joints stuck in either flexion or extension
- progress the exam slowly and carefully
- slow massage or gentle rubbing can help
- cross-table views
Loss of _______ fat can result in decubitus ulcers in geriatrics
Subcutaneous
Why do we not want to use restraints?
They decrease compliance and increase anxiety
What is aprexia?
The inability to use objects correctly
What is one of the greatest dangers facing a premature (sometimes full mature) neonate? How can we prevent it?
Hypothermia
- examine within the warmer whenever possible when using a mobile
- don’t let them come in contact with the IR
- if available, put IR in designated drawer on isolette
- cover IR if drawer not available, be careful of material creasing (artifacts)
What is NAT?
Non-accidental trauma
When dealing with NAT what guidelines should the tech observe?
- pay attention to exposure factors and recorded detail for limb radiography to see subtle skeletal injuries
- when imaging an area multiple times use appropriate centering points, collimation, and techniques
- all views done separately with visualization of the joints (essential)
What steps should the tech observe when imaging a pediatric patient regarding radiation protection?
- proper centering and selection of exposure factors/times, collimation, and use of filters
- keep repeats to a minimum
- follow ALARA, lowest exposure factors
- high mA, low exposure time to reduce motion
- grids used for parts >10cm
- strategic shielding placement
- effective immobilization to reduce repeats
- PA projections of thorax and skull (when possible) to reduce dose
- proper images in general *don’t rely on image reconstructions or computer algorithms afterwards
What is scoliosis?
One or more lateral-rotary curves of the spine
Projections done for scoliosis?
PA or AP of entire spine on single IR
-upright, recumbent, and lateral positions used
Pros/cons of MRI is pediatrics?
- longer exam times, child sedated
- choice exam for spinal cord abnormalities
- cardiac imaging
- brain disorder studies
- epiphyseal fractures
- multiplanar images for surgical assessments
2 of the most successful tools in pediatric radiography?
- communication
- immobilization
When is skeletal growth complete?
Around age 25
What are bone age radiographs used for? What images are taken?
- evaluate the degree of skeletal mutation
- can see how child is developing compared to how they should be
- AP of left hand a wrist
- protocols for 1-2yr olds often include AP left knee
How to reduce patient motion in pediatric radiography?
- communication
- immobilization
- short exposure times
Immobilization devices used in pediatrics?
- Tam-em board: used for chest, abdomen, and upper and lower limbs
- Pigg-o-stat
- Sandbags
- Stockinette and Ace bandage
- Tape
- Weighted angle blocks: used as head clamps
- Mummifying
Pediatrics AP chest recumbent and upright centering
- CR mamillary line/midthorax
- Pigg-o-stat for upright
Lateral chest positions
- immobilization or tam-em board
- CR at midthorax (mamillary line)
- Pigg-o-stat (for upright)
What immobilization technique should you use for upper limb on pediatrics
- sandbags
- parent wearing lead
What should you rule out before attempting a frog leg?
Fracture
Upper GI prep for infants and children?
- Younger than 3 months: NPO 3 hrs prior
- Children 3 months to 5 yrs: NPO 4 hrs prior
- Children 5 yrs + : NPO 6 hrs prior
Lower GI prep for infants and children?
- Infants to 2yr: no prep
- Children 2 to 10yrs: low-residue meal evening before, laxative before bedtime, possible pedi-fleet enema
- Individuals 10yr of age to adult: same prep as adult
IVU prep
- no solid food 4 hrs prior to exam
- encourage drinking of clear liquids
Centering points for upright abdomen on infants vs. older children
- infants: 2.5cm above umbilicus
- older children: 2.5cms above iliac crest
