Diathermy Flashcards
What determines how much energy will be absorbed by the tissue and how warm it will become when using diathermy?
Electromagnetic field intensity and tissue type.
What advantages does diathermy have over other thermal agents?
It can heat deeper tissues than superficial hot packs and heat larger areas than ultrasound.
What are the three types of diathermy applicators?
Inductive coils, capacitive plates, and magnetron.
Which type(s) of diathermy applicators apply shortwave diathermy?
Inductive coils or capacitive plates.
Which type(s) of diathermy applicators apply microwave diathermy?
Magnetron
What structure does NOT reflect shortwave diathermy?
Bone
Microwave diathermy is reflected where?
At tissue interfaces such as those between air and skin, between skin and fat, and between soft tissue and bone.
Inductive coils heat which types of tissues the best?
Tissues closest to the applicator and with the highest electrical conductivity.
Which types of tissues have high electrical conductivity?
Tissues with a high water and electrolyte content such as muscle and synovial fluid.
Which types of tissues have low electrical conductivity?
Tissues with low water and electrolyte content such as fat, bone, and collagen.
What should all be included when documenting diathermy?
area of the body to be treated
frequency range, average power or power setting, pulse rate, time of irradiation, type of applicator, treatment duration, patient positioning, distance of the applicator from the patient, patient’s response to the treatment
What should be the first consideration when considering purchasing a diathermy device?
Whether it outputs a thermal or non-thermal level of energy
T/F With magnetron microwave applicator you place the two plates an equal distance on either side of the area to be treated, approximately 2 to 10 cm from the skin surface.
False, this describes capacitive applicator
When using an inductive applicator with a cable how would you position it on your patient?
cable should be wrapped around the towel-covered limb to be treated, with tuns of the cable spaced at least 3 cm apart and rubber or wooden spacers used to keep cable separated
What is the duration that thermal level diathermy is usually applied?
20 min
T/F Diathermy is a good agent to use for infection control, if patient cannot tolerate direct contact with the skin, or if the area is in a cast.
True pg. 213
You would wrap the area to be treated with towels, to absorb local perspiration, for thermal or PSWD non-thermal diathermy?
Thermal
After starting your patient on diathermy, how long should you wait before checking on them?
check on them after 5 min
How long and often is PSWD usually applied for?
30 to 60 min, once to twice daily
During application of diathermy what should you tell your patient they should expect to feel?
they should feel a comfortable sensation of mild warmth with no increase in pain or discomfort
There are 3 shortwave frequency bands, what are they?
13.56, 27.12, 40.68 MHz
Of those three frequencies, which one is most commonly used for SWD devices?
27.12 MHz
What frequency do microwave components most frequently use?
2450 MHz
What is the shortwave radio frequency signal range?
1.8-30 MHz
