superficial hot modalities Flashcards
hemodynamic effects
vasodilator release, activates cutaneous receptors
vasodilators
histamine and prostaglandin
what happens when cutaneous receptors are activated
smooth muscles relax
- DRG ○ Later on synapsing to lateral gray horn of tc segments ○ Decrease symp adrenegic activation
when you increase temp by 1 degree ncv —- by —-
increases by 2 m/s
effect of hot on demyelinated peripheral enrves
conduction block
hot reduces ___ and ____
- Reduces ischemia and spasm
○ Breaks pain spasm pain cycle
how long should application be for decrease in muscle strength
initial 30 mins
how does thermo alter muscle strength
- Lowered firing rate of alpha motor neurons
Decreased firing rate of: type II muscle spindle efferents and gamma efferents
Increase firing rate of type 1b (GTO)
increase in metabolic rate is seen between ___ and ___ degrees
39 to 43
beyond 45 degrees, what is effect on metabolic rate
enzymatic activity reduced
beyond 50 degrees, what is effect on metabolic rate
○ Enzymatic activities stop
good effect of heat on metabolic rate
- Accelerates healing of chronic wounds
- Shift of o2 dissociation curve to right
○ Makes O2 available for tissue repair
- Shift of o2 dissociation curve to right
bad effect of heat on metabolic rate
- Increase in collegenase activity => destroy articular cartilage
temp and duration for tissue extensibility
40-45 degrees for 10 mins
methods of heat gain
- Conduction
- Convection
- Radiation
hot moist pack storage
70-75 degrees c
hmp is made of
bentonite and hydrophilic silicate gel
terry cloth is equivalent to
4 layers
duration of hmp
15-20 mins
ratio of wax to oil in pwb
6:1
purpose of oil
makes melt at lower temp
melting temp of pwb
45-50
methods of pwb
○ Dip and wrap: 6-10
○ Dip immersion: 20 mins
○ Paint and brush
fluidotherapy
- Dry heating
- Convection moving air
- Cabinet with cellulose inside
lambert’s cosine law
right angle
inverse square law
intensity inversely proprortionate to distance
Law of grothus draper/principle of chemical activation
§ Waves must be absorbed in order to have an effect
- Arndt schultz principle
§ Intensity = warmth
§ There is an optimal amount of energy absorption per unit time
Bunsen roscoe law of reciprocity
§ Intensity and duration are inversely proportional
Near IR/IRA/MIRE
- Short
- Luminous (closer to visible)
- 7701400 nm
- 3x10^8 m/s
- Epidermal and dermal layer
- Penetration: 1-3 mm
- Vigorous rise in temp
Middle or far IRR
- Long
- Non luminous
- 1,400-3000 nm
- Stratum corneum
- 0.1 mm
- Small and gradual rise in temp
Luminous IRR
- From glowing source tungsten or carbon filament
Non-luminous
- Non glowing source like corborundum with metal reflector
Luminous distance
45-60 cm / 18-24 inches
Non-luminous distance
74-91 cm/ 29-36 inches
preheating for IRRs
- Not necessary for luminous
○ Can do 5 min warm up- Non-luminous
○ Requires 5-10 min warmp up
- Non-luminous
optimum time for IRR
20 mins
functions of IRR
Used for pressure sores
adjunct to TENS
- Lowers skin impedance
Psoriasis
contraindications for heat
- Hemorrhage recent or potential
- Thrombophlebitis
- Malignant tumor
- Metal in area
contraindications for IRR
- Acute dermal conditions
- Erythema ab igne
○ Red rash - Over the eyes
- Cardiac insufficiency
- Erythema ab igne
precautions for heat
- Acute injury or inflammation
- Pregnancy
- Impaired circulation
- Poor thermal regulation
- Edema
- Metal close to area
- Recently applied topical counterirritants
- Demyelinated nerves
○ Do not compress - Impaired sensation
- Impaired mentation
precautions for irr
perspiration
irr documentation
at on in x to
contrast bath temperatures
Warm - 38-44 degrees
Cold - 10-18 degrees
use of contrast bath
Vascular pumping mechanism
Benefit of heat while avoiding increased edema
Larger difference for pain or edema
For desensitization: small difference
process of contrast bath
hot for 3-4 mins, cold for 1 min
repeat 5-6 times
end with hot
conversion of Celsius to Fahrenheit
c(9/5) + 32
Fahrenheit to Celsius
(F - 32)(5/9)
vasodilatory effect of heat is the release of
nitrous oxide and bradykinin
