Lecture 3 (heat) Flashcards
What are the 3 kinds of heat therapy?
Moist hot pack
Parafinn
Fluidotherapy
What is thermal conductivity?
How well heat flows through matter
What is heat?
The speed at which particles are moving
How well heat flows is based on 3 things. What are they?
Intensity of heat applied
Time of exposure to heat
**What is being heated **(sticking hand in oven at 212 degrees is a lot different than a bowl of water at 212 degrees) - this is because water is much more conductive than air is –> water will transfer its heat at a much quicker rate than air will and a solid will transfer heat even faster (depending on the solid)
KNOW:
Things that transmit heat from slowest to faster
Air –> Water –> Sold (depends on solid [metal = faster])
Kinetic motion of atoms / molecules of one object is passed on to another object
Hot object comes into contact w/ another hot object is called
Conduction
What two heat modalities utilize conduction?
Moist hot pack, parafin
Object transmits heat directly to skin
KNOW: w/ conduction the easiest way to remember it is sold coming into contact w/ sold or still object coming into contact w/ still object
* think sticking hand into non-moving water. this would be conduction (still object w/ solid object) because nothing is moving
* The other key to conduction is that the objects must be in direct contact
Bulk movement of moving molecules in lquid or gases is called
Convection (remember that theres movement w/ this)
Convexion = bulk movement of moving molecules in lquid or gases
when it gets hot somewhere those molecules take that heat and move elsewhere
think blood flow throughout the body w/ EX
* say were doing grip isometrics = increased heat in that area –> increased blood in that area and heated w/ conduction then the blood moves (heat moving) = convexion (moving heat) and heat is dispursed throughout the body
EX in a nonpainful area causes the painful area to heat up (which is what we want). Is this conduction or convexion?
Its convexion because those heat molecules are being dispursed around the body
NOTE: if pt comes in w/ a back issue and we want to heat it up it would be beneficial to put them on a bike to do this because were getting that theraputic EX while heating the messed up area (bad part is when pt comes in and depends heat pack)
KNOW: this is more effective for heating the body than just putting a hot pack on (conduction) because this is multiple tissues heating up and dispursing throughout the body.
What is the conversion of heat energy to electromagnetic radiation?
Radiation
Do all objects emit / absorb radiation?
Yes - unless they’re absolute zero
Does ice amit radiation?
Yes, any object above absolute zero. However, it doesnt admit that much
Do we use radiation in PT?
No
KNOW: Convexion is moving fluid particles
If I’m trying to heat the entire body could I use a hot pack? If not what would be ideal to use?
No - isnt big enough
Use THEREX
Does muscle return to baseline quickly after heated / cooled? Why or why not?
Will not because of high water content
Why is muscle tissue able to absorb and hold onto heat better?
Increased water content
* note it also does this with cold
Why does fat take longer to heat up than muscle?
Because it has less water content
What holds onto heat / cold longer muscle or fat?
fat because it has bad bloodflow
KNOW: Muscle has loads of blood flow
What temperature is therapeutic?
104-113
Anything under this is normal body temp
At what temperature does tissue damage occur?
above 122
Does heat increase or decrease elasticity?
Increases it (get more flexible / less ridgid when warm)
Does heat increase or decrease viscosity?
Decrease (makes it less thick) (think snow in tubes melting or something boiling becoming les thick)
Does heat increase or decrease joint stiffness
decrease (stifness decreased by heat)
Does heat increase or decrease muscle flexibility
Increase
Will heating a contracture help it?
NO!!! heat effects are not physiologic
Does adding heat change you actaul muscle phsyiology
No!!
Why does heat help to loosen you up / make you more flexible
It helps your brain relax your protective muscle tone (more psycological) DOES NOT psyologically affect your sacromere length!!!
Does adding heat increase sarcomere length?
Nope
Does heat increase or decrease pain?
It depends but it can sometimes help
* on the whole we do use it for pain reduction except under some circumstances
(cold will also decrease pain due to not being able to sense it as much)
KNOW: one way heat helps w/ pain is if the pain is coming from stiffness it will help release the muscle and cause a relief
However, if their pain is for something like fracture or infection it will not help pain (infact it will facilitiate the mechanism of that pain due to increased BF)
Does heat cause vasodilation or vasoconstriction
vasodilation ( = more BF)
* that muscle relaxiation (release of that protective tone) also goes to that smooth muscle in our blood vessels causing them to relax and dilate
* It also causes hormones to be released into the blood causing vasodilatoin
* permability is also increase (tissues can get more stuff into them)
Does heat increase or decrease cell actvity? is it good or bad
Increase
Its good and bad
If were trying to increase some kind of chronic issue we can send more heat there and increase cell activity
* however, we wouldnt want to do this to areas that are already healing properly (we don’t need an excess of blood to an area that already has an appropriate healing response [think an acute fracture w/ lots of swelling])
* However, if the healing process just isnt happening then i might want to - helps restart that healing process
However, we wouldnt want to increase cell activity in a cancer
Why would a younger person be at a smaller risk from a hot pack burning them than an older one?
Because that skin has better blood flow and can tranfer that heat away faster via convexion
we would want to put more layers between them and the heat
KNOW: Young and old people cannot regulate their temperature well
* older / younger will also take longer to retrun to homeostasis
KNOW: When we heat something we get increased emtabolic rate / cellulra activity which = more o2 uptake by tissues (and more oxygen aviability) = more tissue repair
chemoreceptors will feel the O2 leaving and produce more O2
What 3 things cause heat to cause vasodilation of the skin? (superficial vasodilation)
Axon reflex
* Peripheral nerve stimulation increases vasodilation
* Think going out in the sun = warmer = vasodilation of skin to cool the surface (BF cools it)
Release of chemical mediators
* Via mild inflammatory response
* chemicals released that cause vasodilation (think skin getting red when hot = increased vasodilation)
Local spinal cord reflexes
* input to spinal cord results in reduction in vascular smooth muscle activation
* more broad
What two chemicals cause vasodilation?
Prostaglandins / Hisamin (think red response when skin gets hot)
What is the best way to increase muscular blood flow?
EX
what chemical increases vascular permability?
Bradykinin
Neuromuscular effects from heat
Superficial application of heat leads to what two areas of the brain being stimulated
posterior insula / thalamus / hypothalmus (both involved w/ pain regulaton
NOTE: Since they do pain regulation things that might not hurt to a healthy person might hurt to a sick person due to this regulation being out of wack
NOTE: were stimulating these 2 areas and providing a non-noxious stimulus to that area - telling those areas they can feel something other than pain in that area
KNOW: Everyone interprets pain differently
KNOW: exposing area to heat allows us to tolerate more with less pain (increase in pain pressure threshold or superficial nerves [think pushing on a muscle])
What kind of pt gets the best neuromuscular effects from the application of heat?
Chronic pain pt
* because they’re used to the constant bad stimulus so when we apply heat to an area it stimulates those areas of the brain (thalamus and posterior insula) that are used to constalty reporting pain and show them that they can also have a non-noxious stimulus
This pt would also be good because the neuromuscular effects of heat on the muscles are reducing the protective tone –> and chronic pain pts typically have lots of this protective tone
Another neuromuscular effect of applying heat is decreased pain pressure threshold. In chonic pain pt’s they would be affected by that pressure easier (think a non-noxious pushing on muscle would hurt) –> however w/ the application of heat that would increase their ability to have pressure on muscles (increased pain-pressure threshold of superficial nerves w/ heat application)
KNOW: Neuromuscular effects of heat would be reduction in excessive tone/muscular over-activation
and
an increase in pain-pressure threshold of superficial nerves
Would you use heat on someone w/ flared RA?
No - because we don’t heat inflammation (facilitating blood to the area = bonus edema)
What is fibrosis?
Formation of excess fibrous tissue in organs or tissue due to infalmmation or injury - leading to the loss of normal function
- can happen to ligaments and make them more taut
- I’m guessing to can always follow inflammation, so autoimmune issues could also cause it (adhesive capsulitits)
What does heat do to connective tissue?
Typically when combined w/ ROM while heating we can get more eleasticity (this is from decreasing the protective tone not changing anything psycological)
Getting them to relax while doing ROM is what actually helps not just the heat
What happens to muscle max strength when heat is applied? Why?
Decrease it. Muscle becomes more relaxed when heated - so its not going to perform as well
NOTE: we wouldnt want to put heat on an area then test strength
Why would an athelete not want to heat an injury before a game?
Because they would relax their muscles decreasing their contractability
What is the most common heat modality in the clinic?
Moist hot pack
What is a hotpack stored in?
Hydroculator
What temperature should the hotpack be?
104 degrees
How long should hotpacks be applied?
15-20 minutes
we don’t want to go past 20 minutes because the hotpack will have lost most of its heat
How many layers do we need for a hotpack?
6-8
KNOW:
1 layer = towel
tayer cloth = 2 layers
How often should you do skin checks / check in w/ the pt on a hotpack?
Every 5 minutes do skin checks and check on them “does it feel to hot”
What do you do if the hotpack is too hot?
Add more layers
Will the pt feel the heat immediately
No - it warms up as it sits there (starts diffusing through layers)
Should the hot pack be hot immediately
No - we want them to feel it a little bit at first then allow it to be heated up
NOTE: You can be in any position when putting on hotpacks
* just make sure they don’t have any contraindications (active swelling / fracture etc…)
Terry cloth counts as how many layers?
2
KNOW: cervical hot pack pointed down
When must be heat used in treatment?
Not a specific alloted time
KNOW: Need to ask what the pain level of the person was before and after treatment if treating for pain
Or if they came in w/ decreased ROM that im trying to treat i would get a ROM measure before and after treatment
* or ask a pt to do a motion before and after treatment - that will show us pain and ROM
Whatever purpose is make sure you do a test and re-test
KNOW: Hot is also used for ROM (loosens everything up)
MUST REMOVE JEWLERY BEFORE APPLYING HOT PACK BECAUSE IT ABSORBS HEAT
KNOW: Times to use hotpack:
* cervical, thoracic, lumbar pain (w/o swelling
* muscular soreness
* Joint stiffness / pain
KNOW: Hotpack can be used at the same time as:
* EX
* Stretching
* Electrical Stimulatoin
KNOW: Can do it before or after the session (based on their goals)
* I want to leave you feeling better (increased buy in)
* OR
* I want to get you loosened up before you start
You have a pt w/ lumbar stiffness region pain and stiffness
How would you utilize a moist hot pack in a treatment session (when, how long, use with other things?)
Can be used at the start or the end (depending on pt goals)
Use for 15-20 minutes
EX / Stretching can be combine w/ that hotpack
What is paraffin?
Warm, melted paraffin wax
Where is paraffin applied?
Distal extremitites (feet / hands)
What kind of pts would you have use paraffin?
Those who need to get those distal extremitites in between toes and fingers
good for those little areas
NOTE: w/ parafin you’re gonna dip a bunch of times then wrap it (sticker) then bag it and wrap it w/ a towel
probs dip around 8 times
Compare and contrast paraffin dip-and-wrap vs dip-and-reimmerese
Which one is for a higher level of heat transfer
Dip and wrap - what i described above
dip and reimmerse exactly the same but instead of bagging it they just put it back in the wax
* higher level of heat transfer
KNOW: paraffin is good for chonic scar pts (allowing an already healed scar to be mobilized)
KNOW: Can be used in OA / RA pts in non flared state to calm it down
Paraffin contraindications:
* Jewlery must be off
* No open wounds (must be covered w/ banadage)
* Thermal sensation check
note: can do theraml touch sensation for paraffin by having them touch a hotpack to see if they can feel it
how long do parafinns effects alst for
20 minutes till it loses all its heat
Does fluidotherapy work w/ convexion of conduction
convexion
little molecules blown at your arms (makes the air act like a fluid)
No open wounds / jewlery / sensation intact
Good thing about this is that PT can do EX inside the chamber
KNOW: Always check sensation before applying heat or cold to pt
* can touch ice cube to pt or hot pack to see if they can feel it
* we also want a pain response (not just thermal) so we can push a sharp object into them
KNOW: if pt cannot achieve the correct position for intervention we might need to pick a different one
ALWAYS LEAVE CALL BELL
Contraindications for heat:
* Lack of thermal sensation (can’t tell if its too hot)
* Vascular insufficiency (increasing BF to an area that already has blood vessels that can’t handle the amount of blood that are going to that area is a bad thing)
* area of recent hemorrhage (don’t want to increase BF to a hemorrhage [think broken blood vessel)
* Cancer (don’t want to speed up cancer)
* Infection
* Acute inflammation (because the body is trying to heal itself) - think broken bone
* Heat or heating agents recently applied
Precautions:
* pt positioning
* patient draping and modesty
* Bony promineces (if bones are more superficial we need to be careful because were then heating bones)
* age
KNOW: non-inflammed RA is chronic swelling and we can use heat for this
