Therapeutic Heat: Contraindications and Precautions
1. Sreeraj S R
Dr Sreeraj S R, Ph.D.
Heat therapy
CONTRAINDICATIONS
2. Sreeraj S R 2
Contraindication?
▷ A contraindication is a specific situation in which a therapy
should not be used because it may be harmful to the person.
▷ There are two types of contraindications:
• Relative contraindication means that caution should be
used when a therapy is applied. (It is acceptable to do so if
the benefits outweigh the risk.)
• Absolute contraindication means that a therapy could
cause a severe damage or life-threatening situation so must
be avoided.
3. Sreeraj S R 3
Impaired Sensation
▷ Avoid the use of superficial heat when the patient
cannot provide appropriate and timely feedback.
▷ The patient should be able to discriminate
between mild, moderate and intense warmth.
▷ In the absence of appropriate feedback, a patient
can easily be burned before the clinician realizes
that there is a problem.
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Acute Injury, Inflammation
▷ Avoid heating acutely inflamed tissue.
▷ The area should be examined for signs of inflammation:
redness, heat, swelling, pain, and loss of function.
▷ Heat exacerbates inflammatory processes, which may
prolong the recovery period.
▷ Metabolic and vascular changes are induced by local heat,
which perpetuates many inflammatory processes
▷ There is a risk of secondary hypoxic injury when the supply
of oxygen is inadequate to meet tissue demands.
5. Sreeraj S R 5
Haemorrhagic Conditions
▷ Avoid using heat anywhere on the body in an
individual who is at risk of hemorrhage and in
persons with bleeding disorders (hemophilia).
▷ Heat-induced increase in local blood flow may
prolong bleeding.
▷ Tissue heating causes vasodilatation and
increased local and limb blood flow.
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Impaired Circulation
▷ There is a risk of burns if local circulation is insufficient to
dissipate applied heat.
▷ Risk of thrombus formation in PVDs might compromise vital
organs and cause heart attack or stroke.
▷ Increased demand for O2 at heated areas can lead to tissue
necrosis because of poor circulation.
▷ It is important to check hands and feet for signs of arterial
disease (thin, shiny, pale skin; cold to touch; thickened, brittle
nails).
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Malignancy
▷ Local heat can increase tumor growth and
increase incidence of metastases by increasing
blood flow and/or by increasing metabolic rate.
▷ Abnormal growth should be regarded as
malignant until diagnosis has been confirmed.
▷ Applying heat anywhere on the body is a potential
risk.
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Infection, Tuberculosis
▷ Avoid heat directly/indirectly in infections such as abscess, septic
arthritis, TB, infected open wounds, etc.
▷ Applying heat to an area of tissue that is hot, red, and swollen
because of infection can exacerbate swelling and pain.
▷ When body temperature is higher than the physiological norm,
avoid applying heat to large surface areas, as this may produce a
further rise in core temperature.
▷ When a localized infection such as an abscess has an opening for
drainage, mild local heat may help to resolve the infection by
increasing blood flow.
9. Sreeraj S R 9
Active DVT, Thrombophlebitis
▷ The increased circulation may dislodge the
thrombus to form a dangerous emboli with
catastrophic consequences.
10. Sreeraj S R 10
Pregnancy
▷ Avoid applying heat that could elevate core temperature in
pregnant women.
▷ Application of hot packs to the trunk or other surface areas
or full-body immersion in hot water (hydrotherapy tanks)
should be avoided.
▷ Elevation of maternal body temperature (hyperthermia)
causes fetal malformations
▷ Heat can be safely applied to small areas of the extremities.
11. Sreeraj S R 11
Skin Diseases, Chronic Wounds
▷ Heat exacerbates inflammatory-type skin diseases (e.g., eczema/
dermatitis, psoriasis, vasculitis).
▷ Heat conduction is uneven over damaged skin, which might cause
tissue burns.
▷ Increasing tissue temperature increases cell activity and the
demand for oxygen and other nutrients, which may exacerbate the
condition.
▷ Tissues surrounding chronic wounds may be treated with mild
heat, provided there is adequate local circulation.
12. Sreeraj S R 12
Cardiac Failure, Hypertension
▷ Heating a large surface area of the body causes
generalized peripheral vasodilatation and an
increase in core body temperature.
▷ The elevation in skin blood flow requires more
cardiac output to maintain blood pressure.
▷ People with impaired heart function may not
tolerate the increased cardiac demand.
13. Sreeraj S R 13
Metal Implants
▷ Metals have high thermal conductivity;
▷ Therefore, there is high potential for thermal injury
of tissues surrounding heated metal implants.
▷ Metal implants underlying thick subcutaneous or
muscular layers pose a negligible risk.
14. Sreeraj S R 14
Recently Radiated Tissues
▷ Avoid heating tissues that have received radiation therapy
during the last 6 months.
▷ Heat could stimulate the growth of any residual malignant
cells.
▷ Radiation alters cell metabolism.
▷ Increasing tissue temperature stimulates metabolic activity.
▷ This may adversely affect tissue response, especially the
ability to dissipate heat.
15. Sreeraj S R 15
Reproductive Organs
▷ Heat affects spermatogenesis and reduce
fertility.
▷ Heat should not be applied directly to
testes.
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Eyes
▷ Facial skin is normally highly sensitive.
▷ It is likely to damage facial skin that would
cause discomfort
▷ Heat application in the vicinity of the eyes
should be undertaken with caution.
17. Sreeraj S R 17
Obese Individuals
▷ The risk of a burn increases with the
amount of subcutaneous fat, because
▷ fat is an insulator, keeping heat rather than
transferring (conducting) it to adjacent
tissue layers.
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Position
▷ Patients should not lie on top of hot packs
or pads, as pressure compresses skin
capillaires.
▷ This compromises the normal protective
reflex vasodilatation response.
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Heat Intolerance
▷ Heat intolerance or hypersensitivity to the
heat, is a feeling of discomfort when
temperatures rise
▷ that can lead to unpleasant symptoms like
nausea, dizziness, headache, weakness
and muscle aches.
20. Sreeraj S R 20
Medications
▷ Blood pressure medications: thiazide diuretics and beta
blockers.
▷ Antihistamines for allergies: Benadryl (diphenhydramine)
▷ Decongestants: Sudafed (pseudoephedrine)
▷ Stimulant medications for ADHD: Adderall
(amphetamine/dextroamphetamine) and Ritalin
(methylphenidate)
▷ Psychiatric medications: Tricyclic antidepressants,
Antipsychotics, Dopaminergic
21. Sreeraj S R 21
SAFE PRACTICE
▷ Perform a Sensory Discrimination Test
▷ Check Skin Integrity
▷ Monitor for Systemic Temperature Change
▷ Check Skin Response under Heating Agents
▷ Monitor Vital Signs and Watch for Sudden Changes in Blood
Pressure and Syncope.
▷ Use a Bell and Timer
▷ Avoid Pre-treatment of the Area with Superficial Liniments
22. Sreeraj S R 22
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