Week 4: Ultrasound and More Flashcards
Ultrasound contraindications
Bleeding
Decreased sensation
Decreased circulation or DVT
Infection
Malignancy
Over implants
Carotid sinus or cervical ganglia
Growth plates in children
over eyes, heart, genitalia
over cement/plastic
over pregnant woman areas
over pace maker
vascular problems
How far can ultrasound reach under the skin?
5cm
What is attenuation?
The decrease in ultrasound intensity as it travels due to absorption/reflection/refraction
As you increase _______, absorption of Ultrasound increases
frequency
Ultrasound passes through ___________ and is absorbed into ___________
passes through high water content
absorbed into high protein content (tendons)
Ultrasound penetration and absorption are ______ related
inversely
In what order do tissues absorb ultrasound?
LOW - Blood -> Fat -> Nerve -> Muscle -> Skin -> Tendon -> Cartilage/Bone - HIGH
What absorbs more ultrasound muscle or nerves?
muscle
What absorbs the most ultra sound?
What absorbs the least?
Most: bones
Least: blood
Why must you keep an ultrasound moving and keep it level to the skin w/ coupling gel
To prevent hot spots, and prevent reflection from the air
(air reflects 99% of ultrasound)
How does ultrasound work?
Piezoelectric crystals expand and contract w/ AC electric current, causing sound waves
What is the ERA of an ultra sound?
What is the general rule for treatment area?
Effective radiating area, the part that produces the sound waves note: slightly smaller than the actual transducer size, energy output is greatest at the center
Treatment area should be 2-3 times the ERA
What is collimation?
What gives you more?
The focus on the ultrasound beam
As per the slides: A larger transducer with a higher frequency
What is BNR for ultrasound?
Beam nonuniformity
the peak intensity compared to the average intensity, usually set as a ratio. Lower is better. 1:1 is ideal but not possible. Aim for 2:1 or 3:1
Better BNR = Less risk for hotspots
When should you set ultrasound to a duty cycle (1:5 / 20%) vs havingit continous
Duty cycle for non-thermal effects
continious for thermal effects
What frequency of ultrasound do you use for Deep tissues?
For superficial tissues?
Deep- 1MHz
Superficial- 3MHz
How is intensity measured for ultrasound?
W/cm^2 (power unit per area)
When you increase intensity or frequency on ultrasound, you decrease ____________
treatment time
What is nonthermal ultrasound for?
Mild thermal?
Moderate?
Vigorous?
Acute injury/edema
Subacute/hematoma
Chronic inflammation/trigger point
Collagen Stretch
T or F: Water can be used as a medium to apply ultrasound
T
Best for oddly shaped surfaces like the malleoli of the feet
note: use increased intensity as water cannot transmit as well as the gel
How long is the typical ultrasound treatment time?
5-10 minutes
How much heat change is considered mild?
Moderate?
Vigorous?
Mild - 1 C
Moderate - 2 C
VIgorous - 4 C
Ultrasound caution: tissue damage at __C
Continue only if ______
_____effect
45C
There is improvement
Placebo Effect
What is the delivery of medication using ultrasound called?
Phonophoresis
What is ultraviolent light therapy used for?
Chronic ulcer/wounds
What are contraindications to ultraviolent light?
Areas receiving radiation
Diabetes
herpes
Pellagra
Photosensitive medication
Skin Cancer
SLE
TB
What is laser therapy used for?
Using Infared and visible light
For wounds
Tendon/ligament injury
arthritis
edema reduction
soft tissue injury
scar
triggerpoin t
How much depth can laser therapy have?
What kind of light penetrates the deepest?
How does it help wound healing?
2cm
Red and near-infrared
Increase ATP synthesis
proliferation of immune cells
increased blodflow
may modulate pain
What are contraindications to laser therapy
Cancer
Thyroid Dx
Pregnant
Over Eyes
Epilepsy
What is relevant info included in the documentation of modality use
Body part
Modality
patient position
duration
parameters
patient response
skin effects
outcome measure
Are monophasic currents AC or DC?
DC (Direct Current)
What are the advantage of Pulsed Monophasic currents (HVPC)
“comfortable”
Short pulse duration = low risk of chemical burn
What is the advantage of continuous monophasic currents
Unidirectional flow
Accumulation of ions
(used for delivering medicine)
What is better for muscle training, russian current or HVPC?
Russian
HVPC duty cycle as per treatment goals:
NMR:
Muscle Pump:
Reduce atrophy/strenghten:
ROM:
NMR: 1:5 -> 1:3 -> 1:1
Muscle Pump: 1:1
Reduce atrophy/strengthen: 1:5
ROM: 1:1 or 1:5 depending on fatigue
Does HVPC use modulation?
What are you looking for when you use HVPC?
No
Muscle Contraction
When using HVPC to reduce atrophy, what intensity and volume should you use
Move through gravity resisted range, 25%+ of MVIC
3x10 repetitions x2 a day
When using HVPC for strengthening, what intensity should you use?
60% of MVIC, 3x10 repititons
Pt works w/ e-stim against resistance
How do you use HVPC for edema control? (example: ankle sprain)
larger dispersive electrode is proximal
Smaller active electrode on the site of swelling
elevate the extremity
Frequency: 120pps
pulse duration: low
note: not looking for muscle contraction, just voluntary
When using HVPC, which electrode do you put over the wound?
Cathode, swich electrode every 1-3 days.
The cathode has antibacterial properties
the cathode has a ______ effect, the anode has a _______ effect
alkaline
acidic
What settings should you use for iontophoresis?
Intensity: 3-5mA
Current density: 0.1 to 0.5
time: 10-20 mins
How do you complete the circuit for an at-home iontophoresis unit?
add saline to opposite electrode that the medicine goes into
If a medicine is negatively charged, it must go on the _____ electrode to enter the skin
Where does positive go?
negative electrode
On the positive electrode
When using iontophoresis, what is important to do after the treatment?
check skin for chemical burn
What should iontophoresis feel like?
tingling/prickling sensation
Iontophoresis dose is expressed in mA-min meaning current x time)
So if a 40 mA -min dose = 2mA current x 20 minutes.
How do you deliver it twice as fast?
By changing the current to 4mA
40mA = 4mA x 10
Calcium medications have what charge?
Dexamethosone has what charge?
Lidocaine?
Positive
Negative
Positive
Which electrode will calcium and lidocaine medication go on?
Postitive
Which electrode will dexamethosone go on?
negative
Iontophoresis contraindications
Same as Estim +
Impaired skin sensation
allergy to medication
denuded areas of recent scar
cut/bruises
metal in or near treatment site
When using iontophoresis at home, how long should the patient keep the electrode on?
8-14 hours
How should we educate patients for iontophoresis at home?
Instruct about sensation
teach cleaning
trim but dont shave
dont overfill or compress pad once applied
keep electrode on 8-14 hours
take electrode off under running water
may apply lotion after electrode removal
Which electrode usually causes a burn during iontophoresis?
An alkaline reaction burn at the cathode
maybe also due to poor contact or too much resistance
How to minimize burns using iontophoresis?
Decrease current density
inspect skin
ensure proper filling of meds
ensure good contact w/ skin
ask about allergies
What is biofeedback?
NOT E-stim, but electrodes that measure current in muscle
will beep when patient uses that muscle, more beeping = more use
good for encouraging patients to use or not to use certain muscles
example: u dont want them to use upper trap to shrug while lifting arm
What happens if you place electrodes too far apart when using biofeedback?
might detect other muscles
How to set the sensitivity for biofeedback?
Use the lowest level that does not elicit feedback at rest
high sensitivity needed for relaxation training (theyre trying to reduce feedback to zero)
Low sensitivity for NMR (attempting to increase the feedback)
feedback = beeping
What is pressure-sensitive biofeedback?
NMR used to train specific muscles, uses a cuff that detects pressure, pressure changes when u contract muscle
Criteria for selection of biofeedback use for patients
Patients need good vision/hearing/communication
good comprehension of simple commands
good motor planning
no profound sensory or proprioception loss
What penetrates deeper, cooling or heat?
(ice packs or hot packs)
cooling
Thermotherapy contraindications
Acute/subacute injury
Decreased circulation
Decreased sensation
DVT
Impaired cognition
Malignant tumors
Tendancy toward hemorrhage or edema
very young or elderly
thermotherapy PRECAUTIONS (not contras)
Cardiac insuffiency
edema
impaired circulation
impaired thermoregulation
pregnancy
topical counterirritants recently applied
demyleinated nerves
open wounds
What is the normal temp of a hydrocollator?
160-170F
Is erythema bad after applying a hot pack
No
But wheals, welts, and molted skin are bad
How often should you check a patients skin while on a hot pack
Every 5 minutes
How many layers of towel should you put between a patient and the hot pack
6-8
Note: terry cloth cover counts as 4
T or F, you should have lower back patients lay on the hot pack
F, don’t let them lay on the hot pack bc it increases heat transfer, risk of burns
What are the 4 normal sensations a patient should feel when doing cryotherapy (in order)
Cold
Burning
Aching
Numbness
What should a patient do immediately after receiving thermal therapy?
Exercise
