Heat and cold therapy

Question 1

physical effects of heat

Answer 1

rise in temperature- increased average kinetic energy of molecules
expansion- molecules move further apart
change in physical state- solid to liquid, liquid to gas, latent heat of fusion, evaporation
acceleration of chemical reactions
reduction in viscosity of fluids

Question 2

what does the physiological effect of heat depend on-

Answer 2

size of heated area, depth of absorption, duration of heating- at least 20 mins to have a decent physiological effect, intensity of heating- depends on what is being heated and what form of heating, methods of application

Question 3

what does the physiological effect of heat depend on- depth of absorbtion

Answer 3

depends on how heat is produced, and what tissues are being exposed to it- bones absorb more heat than soft tissue, therefore heating tends to be superficial

Question 4

local physiological effects of heat- increased metabolic activity

Answer 4

more demand for oxygen and nutrients, increase output fo waste products, tissue damage above 45°- 1 hour/50°- 1 min/ 65°-1sec

Question 5

local physiological effects of heat- increased blood flow

Answer 5

surface vessels dilate (erythema), more red and white blood cells, may lead to oedema

Question 6

local physiological effects of heat- other

Answer 6

extensibility of collagen may be increased, joint stiffness reduced- good for Rha/ oa, muscle spasm reduced, pain relief- pain gate theory, healing encouraged, sweating

Question 7

indications of heat therapy

Answer 7

extensibility of collagen fibres- e.g. scar tissue, joint stiffness reduced (arthritis), muscle spasm reduced. pain relief- pain gate theory, increased rate of healing

Question 8

dangers of heat therapy

Answer 8

burns, calds, overdose- exacerbation of problem ,perception of gangrene, electric shock

Question 9

contraindications of heat therapy

Answer 9

lack of thermal sensation, impaired circulation- can’t get rid of heat= burn, risk of haemorrhage, devitalised skin (e.g. radiotherapy), some skin conditions

Question 10

what should always be done before heat therapy

Answer 10

always test sensory awareness before applying hot and cold therapy, always warn patient there is a risk of burns- mark down this has been said

Question 11

methods of superficial heatin

Answer 11

paraffin wax baths, hot packs from a hydrocollator, wheat (lavender) bags, electric heat pads, luminous and non- luminous

Question 12

paraffin wax box

Answer 12

melting point 54°- reduced to 42-50° by mineral oil, a form of conductive eat, large amount of energy released on solidification- latent heat of fusion, insulation, treatment duration 15-20°

Question 13

hydrocollators

Answer 13

hot packs- produce physiological effects by conduction, hydrophilic silicate gel in cotton wrapping, 75-80° in water bath, wrapped in towel providing insulation- prevent skin exceeding 40-42°, treatment duration- 20 mins

Question 14

wheat lavender bag

Answer 14

used with arthritic conditions, be mindful of weight of heat packs

Question 15

prevention

Answer 15

risk assessment, detailed explanation of proposed treatment, seek informed consent, check (ask, observe, palpate) for contraindications, test thermal sensation of treatment area and surrounding areas, give warning to patients, safe application, recording of the above

Question 16

physiological effects of cold

Answer 16

decreased metabolic rate, vasoconstriction followed by (15-20 mins), cold induced vasodilation (erthreyma) followed by lewis hunting reaction, increased blood viscosity, may reduce swelling, cold and pain sensation followed by numbness- initiation of nerve conduction, thinly myelinated A fibres mostly affected, hypertonicity reduced- action on muscle spindles, below 5°- tissue damage, slowed healing, subcutaneous fat shields deeper tissues

Question 17

how does cold therapy work

Answer 17

the transfer of heat energy away from the body causing local effects

Question 18

therapeutic cooling- cryotherapy- method of application

Answer 18

cold packs- ice chips in towelling, cold packs- commercial, reusable, ice towels, immersion 16-18°, ice massage, vaporising spray

Question 19

cryocuff

Answer 19

used post knee replacement, post shoulder surgery, put ice and water and lift lever up- through gravity it fills the cuff up

Question 20

indications of cold therapy

Answer 20

decreased oedema production, reducing in bleeding/swelling, recent acute injury/post injury, minimise acute inflammation, reduce muscle spasm/spasticity- use hot, psychological not best for high tone, reduces pain, reduce chronic oedema and joint effusion

Question 21

contraindications- cold therapy

Answer 21

decreased sensation to heat/cold, peripheral vascular disease- arteries not taking blood into them- cause ice burn- cold cannot be dissipated around the body, vasospasm- raymund disease, cryoglobulinemia (abnormal blood proteins), cold urticaria- histamine release

Question 22

danger- cold therapy

Answer 22

ice burns, fatty necrosis- bruising, frostbites

Question 23

precautions cold therapy

Answer 23

cardiac disease- not near heart, altered blood pressure, defective thermal sensation, skin hypersensitivity, adverse psychological issues

Question 24

acute inflammation, chronic inflammation, promote healing, collagen. extensibility, stiffness, spasm- heat and cold

Answer 24

heat- No, yes, yes, yes, yes, yes

cold- yes, ?, no, no, no, yes

Question 25

spasticity, hands/feet, home treatment, pain relief- heat and cold

Answer 25

heat- ??, yes, yes

cold- yes, no, yes, ??, yes