Heat & Heat Transfer
What happens to blood flow when heat is applied?
It increases
What is inside a hydrocollator pack?
Silica gel
What does RICE stand for?
Rest, Ice, Compression, Elevation
What type of heat does fluidotherapy use?
Dry heat
Is ultrasound superficial or deep heating?
Deep heating
What is conduction?
Heat transfer through direct contact
What temperature are hydrocollator packs stored at?
160–170°F
What happens to blood vessels during vasoconstriction?
They narrow and blood flow decreases
What are the 2 heat-transfer mechanisms used by a whirlpool?
Conduction and convection
Q: Why should the ultrasound transducer keep moving?
To spread energy evenly and prevent overheating
What is convection?
Heat transfer through the movement of fluid or air
What temperature is a paraffin bath?
126–130°F
How long should an ice massage last?
5–10 minutes
How far should the body part be from a whirlpool agitator?
6–8 inches
What ultrasound technique is useful for irregular body parts?
Immersion technique
What are 4 effects of heat?
Increased blood flow, increased metabolism, increased collagen extensibility, decreased pain/muscle spasm
Why are 6–8 towel layers used with a hydrocollator pack?
To prevent burns
What is the hunting response?
Alternating vasoconstriction and vasodilation during prolonged cold
What temperature is used for fluidotherapy?
100–118°F
What intensity of ultrasound is used mainly for non-thermal effects?
Low intensity
Name the 6 contraindications for superficial heat.
Acute injury/inflammation, active bleeding, impaired sensation, decreased arterial circulation, cancer, and infection
A patient has chronic hand stiffness before stretching. Which modality should be used?
Paraffin
Why should someone be careful returning to activity after icing?
Cold can temporarily decrease strength, sensation, and reflexes
What happens to the recommended whirlpool temperature when more of the body is immersed?
The temperature should decrease
A patient has an acute injury with swelling and pain. Heat or cryotherapy? Why?
Cryotherapy because it helps decrease swelling and pain and is appropriate for acute injuries