*3.PTA 200-Superficial Thermal Agents Flashcards
How does heat transfer?
Heat always transfers from higher concentrations to lower concentrations.
The application of heating or cooling modalities to treat disease and other traumatic injuries.
Thermal Agents
The therapeutic application of heat
Thermotherapy
The therapeutic application of cold
Cryotherapy
Heat exchange through direct contact between materials with different temperatures. Examples
―Hot packs
―Cold packs
―Cold water soak
Debbie’s example-The higher the difference in concentrations, the faster the heat will transfer. **This is the principle that allows for burns or frost bite!
superficial
Conduction
Transfer of heat by the movement of air, matter, or liquid around the body. Examples
―Warm Whirlpool
―Cold Whirlpool
Debbie’s example-Two objects of different heat concentrations come into direct contact with each other while one is being circulated around the other.
superficial
Convection
Heat transfer through the air from a warmer to a cooler source. Examples
―Infrared Heat Lamp
Debbie’s Example-Heat is transferred from higher concentration to lower concentration without contact between surfaces. No required medium for transport.
deep
Radiation
Heat released when energy is transformed from one form to another. Examples
―Ultrasound
Debbie’s example- A non-thermal form of energy becomes transformed into a heat energy.
deep
Conversion
Heat released when a liquid changes to a gas state. Examples
―Perspiration
―Spray & Stretch
Debbie’s Example-Energy is absorbed during a change in physical form of a material.
Evaporation
blood & muscle (due to high water content)- Tissues With High Thermal Conductivity (rate at which the material transfers heat through conduction/contact with that medium)
adipose tissue- Tissues With Low Thermal Conductivity (act as insulators for heat traveling from one source to another)
Debbie's Example-Describes the rate at which heat is transferred through a substance by conduction. Metals: highest conductivity Ice Water Bone Muscle Fat Air: lowest conductivity
Thermal Conductivity
Measures the amount of energy required to increase the temperature a certain amount of material a certain # of degrees.
( 1 kg substance ↑ 1 degree Celsius)
Important because:
High specific heat values = ↑energy required to create a temperature change to the tissue.
High specific heat values = longer duration of sustained amount of energy.
Specific Heat
What are the contraindications for thermotherapy?
- recent or potential hemorrhage
- thrombophlebitis (is swelling of a vein caused by a blood clot.)
- impaired sensation
- impaired mentation
- malignant tumor
- IR irradiation of the eyes
What are the precautions with thermotherapy?
- acute injury or inflammation
- pregnancy
- impaired circulation
- poor thermal regulation
- edema
- cardiac insufficiency
- metal in the area
- over an open wound
- over areas where topical counterirritants have recently been applied
- demyelinated nerves
What are the contraindications for cryotherapy?
- cold hypersensitivity
- cold intolerance
- cryoglobulinemia (presence of abnormal proteins in the blood. These proteins thicken in cold temperatures.)
- Paroxysmal cold hemoglobinuria (is a rare blood disorder in which the body’s immune system produced antibodies that destroy red blood cells when they go from cold to warm temperatures.)
- Raynaud’s Disease (s a condition in which cold temperatures or strong emotions cause blood vessel spasms. This blocks blood flow to the fingers, toes, ears, and nose.)
- Over-Regenerating peripheral nerves
- Over an area with circulatory compromise or peripheral vascular disease.
What are the precautions for cryotherapy?
- over the superficial main branch of nerves
- over an open wound
- hypertension
- poor sensation or mentation
- very young and very old patients
