Thermal Agents: Heat

1
Thermal Agents Heat

• HuP 195

2
Heat modalities Superficial Heat

• Skin temperature rises but subQ tissue increase
  is minimal
• 1cm penetration
• depth of penetration is related amount of fat in
  area

• HP
• Whirlpools
• Paraffin Baths
• Infrared Lamp

3
Heat Modalities Deep Heat

• Ultrasound and diathermies
• Transmits well through superficial tissue layers
• 3-5cm penetration

4
Factors effecting tissue temperature rise

• temperature gradient/rate high or low vs. time
• volume of tissue if treatment area is great
  there may be a decrease in BP from hypothalamus
  (vasodilatation)
• Duration of treatment
• 100-113F is needed to get an effect

5
Factors effecting tissue temperature rise

• Beyond 113 ÞF protein denaturization and tissue
  burning may occur
• Heat is dissipated faster because of increased
  blood flow
• Best general tissue temperature and blood flow
  increase is via exercise

6
Physiological effect of superficial heat
Metabolic

• Increase metabolic rate
• Increase oxygen demand
• Therefore the is increased cell death with
  swelling

7
Physiological effect of superficial heat
Hemodynamic

• Depth of effects are not as great as with cold
• Vascular changes are confined to skin (1cm)
• So Why use it?

8
Physiological effect of superficial heat
Hemodynamic

• Capillary dilation is the main effect from
• axon reflex (non-synaptic) release of substance
  from axon causing arterioles to relax
• Chemical mediators released causing mild
  inflammatory reaction
• Spinal cord reflex A-delta fibers carry
  temperature to spinal cord to inhibit sympathetic
  activity causing vasodilatation

9
Physiological effect of superficial heat
Neuromuscular

• Increase sensory nerve conduction
• Temperature is carried on A-delta fiber
• Analgesic effects both distal and proximal to
  area treated
• This is why non-acute back patients use heat
  instead of ice

10
Physiological effect of superficial heat
Neuromuscular

• Firing of II fibers results in a decrease in
  muscle firing, reducing muscle spasm
• Increased golgi tendon organ firing which
  inhibits muscle contraction

11
Physiological effect of sup. heat Connective
tissue

• plastic or viscous properties permit residual
  elongation after stretch is applied and released
  (plastic deformation)
• elastic properties result in recoverable
  deformation
• Heat aid elongation (heat with stretch works best)

12
Indications for the use of superficial heat

• Muscle spasm
• Subacute inflammation
• Trigger points
• Thrombophlebitis (Inflammation of a vessels due
  to an obstructing blood clot)
• Local inflammation (caution!)

13
Contraindications for the use of superficial heat

• Acute inflammation
• Decrease sensation in area
• Impaired circulation (unable to dissipate heat)
• Malignancies increased metabolic rate
• Pregnancies

14
Moist Heat Packs

• Canvas Pouch with Silica Gel
• Pack is kept in a water-filled heating unit
  maintained between 160º F -170 º F
• Pack maintain temperature for 30-45 minutes
• Packs transfer heat by conduction
• Main benefit is superficial heat to 1cm

15
Moist Heat Packs

• Set-up
• Cover pack with terry cloth covering
• Place pack on patient in comfortable manner
• Check patient within 56 minutes for comfort
• Allow pack to reheat for a minimum of 30 minutes
  before reuse

16
Moist Heat Pack

• Indications
• Subacute or chronic inflammatory conditions
• Reduction of subacute or chronic pain
• Subacute or chronic muscle spasm
• Decreased ROM
• Hematoma resolution
• Reduction of joint contractures
• Infection

• Precaution
• infected areas must be covered with gauze
• Contraindications
• Acute conditions
• Peripheral vascular disease
• Impaired circulation
• Poor thermal regulation

17
Paraffin Bath

• A mixture of wax an mineral oil in a ratio of 7
  parts wax to 1 part oil
• Temperature of 118º F to 126 ºF for upper
  extremity tx.
• Temperatures of 113 º F to 121 º F for lower
  extremity (circulation is less efficient)
• Paraffin can provide approx. 6x the amount of
  heat as water due to low specific heat.

18
Paraffin Bath

• Used to deliver heat to small irregularly shaped
  areas (hands, fingers, wrist and foot)
• Increases intrarticular heat 6.3 ºF

19
Paraffin Bath Set Up

• Immersion Bath
• Clean body part
• Dip both part an allow coat to dry
• Dip the extremity 6-12 more times
• Then place extremity back in paraffin for
  duration of tx (10-15 min)
• DO NOT touch sides or bottom of bath (burns)
• After tx scrape of was and replace in bath

• Pack (Glove) MethodClean extremity
• Immerse extremity in bath and allow wax to dry -
  repeat 7-12 more times
• After final withdrawal from wax, cover extremity
  with plastic bag, aluminum foil, or wax paper.
  Then wrap in terry cloth towel
• If indicated elevate body part
• Following tx remove wax and return to bath

20
Paraffin Bath

• Precautions
• Sensation is different from specific heat and
  thermal capacity - may cause burns
• Avoid using with athlete who are required to
  catch or throw a ball - skin becomes slippery

• Contraindications
• Open wounds
• Skin infections
• Sensory loss
• Peripheral vascular disease
• Indications
• Subacute and chronic inflammation
• limitation on ROM after immobilization

21
Infrared Lamp

• Radiant energy
• 2 types luminous (infrared) and nonlumious (far
  infrared)
• Luminous produces some visible light (as opposed
  to nonluminous), nonlumious is less penetrating
  than luminous

22
Infrared Lamp Set-up

• Warm lamp if necessary
• Clean area for any sweat, dirt, or oils and
  remove jewelry
• Position patient in a comfortable manner
• Place lamp so that the source of heat is approx
  24 inches away from patient
• To prevent burns, instruct patient not to move
• Check patient periodically
• Duration 20-30 minutes

23
Infrared Lamp

• Indications
• Subacute or chronic inflammatory conditions
• Skin infections
• Peripheral nerve injuries before electrical
  stimulation

• Contraindications
• Acute conditions
• Peripheral vascular disease
• Areas with sensory loss or scarring
• Sunburns

24
Whirlpools

• Tx temperature is between 105º-110º F the larger
  the area the less the temperature down to 100º F
  for whole body
• Tx times begin with 5-10 minutes and may be
  increased to 20-30 minutes once or twice daily

25
Warm Whirlpool

• Precautions
• Must be connected to ground-fault indicator
• Instruct patient not to turn whirlpool motor on
  or off while in whirlpool
• Patient should be continually monitored
• Do not run while turbine is dry
• Flowing water may nauseate some patients
• Patients under the influence of drugs

26
Warm Whirlpool

• Indications
• Decreased ROM
• Subacute or chronic inflammatory conditions
• Peripheral vascular disease
• Peripheral nerve injuries
• Irregular shaped areas

• Contraindications
• Acute conditions where water turbulence would
  further irritate injured area
• Fever
• Patients requiring postural support
• Skin conditions

27
Transitions from cold to heat

• No signs of increased inflammation decreased
  swelling
• No increase in tissue temperature
• If decreased range from pain-stay with cold
• Change to heat when effect from ice applications
  plateaus
• If decrease range from stiffness then use heat

28
Contrast Treatments

• Used as a transition between cold and heat
• Allows type of vascular pumping via cold/hot/cold
  treatment ?
• May use water or ice packs/hot packs etc..
• May vary the length of time in cold vs.. heat
  depending on effects desired
• Ending of treatment should reflect effect you
  want to end with
• Latest research says ineffective

29
Contrast Bath Set Up

• Two tubs placed as close together as possible
• Fill one tub in the range from 105 F-
  110 F and the other 50 F - 60 F
• Position patient on chair or bench between two
  tubs
• Heat Tx given 1st
• Contrast bath 20 -30 minutes at 3-5 minute
  intervals or a combination (3 min hot 5 min cold
  etc.)

30
Contrast Bath

• Precautions
• Same as with all whirlpools
• Indications
• Ecchymosis removal
• Edema removal
• Subacute or Chronic Inflammation
• Impaired circulation
• Pain Reduction

• Contraindications
• Acute injuries
• Hypersensitivity to cold
• Contraindication relative to whirlpool use
• Contraindications relative to cold application
• Contraindications relative to heat application