Superficial Heating And Cooling Flashcards
What is temperature?
- Measure of the level of heat
- Provides energy of motion to molecules
- Increased molecule = increased motion = increased friction = increased heat
What is therapeutic heating?
Transferring heat from an external environment to the body surface which transfers heat to deep tissues and fluids of the body
What three ways is heat transferred by?
Conduction
Convection
Radiation
Describe conduction…
Needs direct contact to transfer energy
It’s the kinetic motion of molecules passed from one to another
Describe convection…
Bulk movement of heated molecules
Heated molecules move from one place to another
Example: hot pack heats up superficial blood vessels which heats other parts of the body
Describe radiation:
Conversion of heat to an electromagnetic radiation
Radiation travels through space
Example: our bodies give off infrared radiation
What does the rate of heat transfer depend on?
Difference in temp between two regions
Surface area in contact
Thermal conductivity of materials - ability to give off heat
What is evaporation and why is it important?
Change of state of molecule- eg hot to cold
Energy taken from surface tissue to remove heat
Be careful when heating patients because sweat can cause scolds
What is thermoregulation?
Constant body temperature of 37 +/- 2 degrees
Maintained by body surfaces and environment
Requires a balance of heat gai and heat loss
Extremities can differ to -6 degrees less
Temperature across the body depends on:
CNS hypothalamus Behavioural response Physiological response e.g shiver Thermoreceptors in skin Mechanoreceptors - stimulate pain gate
What are the physical effects of higher temperature?
High temp = increased kinetic energy Expansion - molecules move further apart Changes in physical state Acceleration of chemical reactions Reduction in viscosity of fluids - stickiness
Physical effects depend on:
Size of heated area
Depth of absorption
Duration of heating
Methods of application
What are the local physiological effects of high temperature?
Increased metabolic rate - increase demand for oxygen and nutrients
Increase blood flow - vasodilation - can lead to oedema - ice in first 72 hours
Reduce joint stiffness
Pain relief
Healing encouraged
What are the methods of superficial heating?
Paraffin wax baths Hot packs from hydrocollator Electric heat padS Infrared lamps Wheat bags
What temperature is the wax paraffin bath set to
Melting point is 54 degrees
Cooled to 45 degrees
How long should the wax bath be applied for
15-20 minutes
What should you do after wax treatment?
Tidy equipment
Dispose wax accordingly
Examine treated area
Document treatment
What are hydrocollators?
Big water bath with hot packs in
Uses conduction
Heated to 75 degrees
20 minutes treatment or until cool
What are the dangers of heating treatment?
Burns Scolds Gangrene - with poor circulation Electric shocks Overdose
What are the contraindications of heating?
Lack of thermal sensation Impaired circulation Risk of haemorrhage Devitalised skin Some skin conditions like eczema
What is mandatory of heat treatment?
Risk assessment Informed consent Check - ask observe and palpate Check contraindications Test thermal sensation Give warnings of how they should feel Safe application Documentation
What are the types of cooling treatments?
Cold packs - ice chips Cold packs - reusable gel packs Ice towels Ice massage Vaporising sprays Cyrocuff orthopaedic
What are the physiological effects of cooling?
- Reduced metabolic rate
- Vasoconstriction for 5-15 mins > vasodilation > Lewis hunting reaction (alternate vasoconstriction and dilation)
- reduced oedema
- reduced swelling
- cold and pain sensation e.g. Numbness - inhibits nerve conduction
- blood viscosity increased
- High tone reduced
- slowed healing
When would you use cooling treatments?
To reduce oedema Reduce bleeding Recent acute injury or post surgery Acute inflam Reduce muscle spasm Reduce pain Reduce chronic oedema
What are the contraindications for cooling?
Reduce sensation Peripheral vascular disease Raynauds Abnormal blood proteins Cold uiticana - rash due to histamine release
What are the precautions of cooling?
Cardiac disease Altered bp Thermal sensation defect Skins hypersensitivity Psychological effects
What are the dangers of cooling?
Ice burns
Bruising
Frostbite
What is heat?
Form of energy
Measured in joules
