HEAT AND COLD

THERAPY
Heat and cold are applied in the body to promote the repair and healing of
tissues. The form of thermal application generally depends on their purpose.
Cold applied to a body part to draws heat from the area. Heat of course
warm the area.. The application of heat and cold produces physiologic
changes in the temperature, size, of the blood vessels. Capillary blood
pressure. Capillary surface area for exchange of fluid and electrolytes and
tissue metabolism. The duration of the application also affects the response..

Heat and cold can be applied to the body in both dry and moist forms. Dry
heat is applied locally, for heat conduction, by means of a hot water bottle,
electric pad, , aquathermia pad, or disposable heat pack. Moist heat can be
provided, through conduction, by compress, hot pack, soak, or bath. Dry
cold is administered for local effect by the use of ice bags, ice collars,, ice
gloves and disposable cold packs. Cold moist compresses are administered
to body parts for local effect, tepid sponge baths are given for a systemic
cooling effect. Cold is often applied to the body to decrease bleeding by
constricting blood vessels to decrease inflammation by causing
vasoconstriction, and to decrease pain by slowing nerve conduction. rate,
producing numbness, and acting as counter irritant
GUIDELINES FOR APPLYING
HEAT AND COLD
An understanding of the adaptive response of thermal receptors,the rebound phenomenon,systemic effects,tolerance to
heat and cold,and contraindications is essential when administering hot and cold applications.

1.Adaptation of Thermal Receptors

Thermal receptors adapt to temperature changes.When a cold receptor is subjected to an abrupt fall in temperature
or when a warmth receptor is subjected to an abrupt rise in temperature,the receptor is strongly stimulated
initially.This strong stimulation declines rapidly during the first few seconds and then more slowy during the next
half hour or more as the receptor adapts to the new temperature.
Nurses need to understand this adaptive response when applying heat and cold.Clients may be tempted to change
the temperature of a thermal application because of the change in thermal sensation following adaption.Increasing
the temperature of a hot application after adaption has occurred can result in serious burns.Decreasing the
temperature of a cold application can result in pain and serious impairment of circulation to the body part.

2.Rebound Phenomenon
The rebound phenomenon occurs at the time the maximum therapeutic effect of the hot or cold application is
achieved and the opposite effects begins.For example,heat produces maximum vasodilation in 20 to 30 minutes;
continuation of the application beyond 30 to 45 minutes brings tissue congestion, and the blood vessels then
constrict for reasons unknown. If the heat application is continued further,the client is at risk for burns,since the
constricted blood vessels are unable to dissipate the heat adequately via the blood circulation.
With cold applications,maximum vasoconstriction occurs when the involved skin reaches a temperature of 15
degrees C, vasodilation begins. This mechanism is protective: It helps to prevent freezing of body tissues normally
exposed to cold, such as the nose and ears. It also explains the ruddiness of the skin of a person who has been
walking in cold weather.
An understanding of the rebound phenomenon is essential for the nurse. Thermal application must be halted before
the rebound phenomenon begings.
PHYSIOLOGIC EFFECTS
OF HEAT AND COLD
HEAT COLD
Vasodilation -Vasoconstriction
Increase capillary permeability -Decreases cellular metabolism
Relaxes muscles -Relaxes muscles
Increases
inflammation;increases blood -Slows bacterial
flow to an area growth,decreases
Decreases pain by relaxing
inflammation
muscles -Decreasing pain by numbing
the area,slowing the flow of
Sedative effect pain impulses,and by
Reduces joint stiffness by
increasing the pain threshold
decreasing viscosity of synovial -Local anesthetic effect
fluids -Decreases bleeding
 SELECTED INDICATIONS OF HEAT
AND COLD
INDICATION EFFECT OF HEAT EFFECT OF COLD

-Muscle spasm -Relaxes muscles and -Relaxes muscles and

increases their contractility decreases their contractility
-Inflammation -Increases blood -Vasoconstriction decreases
flow,softens exudates capillary
permeability,decreases
blood flow,slows cellular
metabolism
-Pain -Relieves pain,possibly by -Decreases pain by slowing
promoting muscle nerve conduction rate and
relaxation,increasing blocking nerve
circulation,promoting impulses,produces
psychological relaxation numbness,acts as a
and a feeling of counterirritant,increases
comfort;acts as a pain threshold
counterirritant
-
con’t.
Contracture Reduces contracture and
increases joint range pf
motio by allowing greater
distention of muscles and
connective tissue

Joint stiffness Reduces joint stiffness by

decreasing viscosity of
synovial fluid and increasing
tissue distensibility

Traumatic injury -Decreases bleeding by

constricting blood vessels,
decreases edema by
reducing capillary
permeability
RECOMMENDED TEMPERATURES FOR HOT AND COLD
APPLICATIONS
DESCRIPTION TEMPERATURE APPLICATION

𝙑𝙚𝙧𝙮 𝙘𝙤𝙡𝙙 Below 15°C (59°F) Ice bags

𝘾𝙤𝙡𝙙 15 - 18°C (59 - 65°F) Cold pack

𝘾𝙤𝙤𝙡 18 - 27°C (65 - 80°F) Cold Compressed

𝙏𝙚𝙥𝙞𝙙 27 - 37°C (80 - 98°F) Alcohol Sponge Bath

𝙒𝙖𝙧𝙢 37 - 40°C (98 - 105°F) Warm Bath,

Aquathermia Pads
𝙃𝙤𝙩 40 - 46°C (105 - 115°F) Hot soak, irritations, hot
compressed
𝙑𝙚𝙧𝙮 𝙝𝙤𝙩 Above 46°C (above Hot Water bags for
115°F) adults
Variables Affecting physiologic
Tolerance to Heat and Cold
Body parts. The back of the hand and foot are not every
temperature sensitive. In contrast, the inner aspect of the wrist
and forearm, the neck, and the perennial area are temperature
sensitive.
Size of the exposed body part. The larger the area exposed to Heat
and cold, the lower the tolerance.
Individual tolerance. The very young and the very old generally
have the lowest tolerance. Person who have neurosensory
impairments may have a high tolerance, but the risk of injury is
greater.
Length of exposure. People feel hot and cold applications most
while the temperature is changing. After a period of time,
tolerance increases.
Intactness of skin. Injured skin areas are more sensitive to
temperature variations.
 Contraindications to use of
heat and cold
Determine the presence of any conditions contraindicating to
use heat:
 The first 24 hours after traumatic injury. Heat increases
bleeding and swelling.
 Active hemorrhage. Heat causes vasodilation and increases
bleeding.
 Non inflammatory edema. Heat increases capillary
permeability and edema.
 Localized malignant tumor. Because heat accelerate cell
metabolism and cell growth and increases circulation, it may
accelerate metastases (secondary tumors).
 Skin disorder that causes redness or blisters. Heat can burn
or cause further damage to the skin.
Determine the presence of any conditions
contraindications the use of cold:
 Open wounds. Cold can increase tissue damage by
decreasing blood flow to an open wound.
 Impaired circulation. Cold can further impair nourishment
of the tissues and cause tissue damage. In clients with
Raynaud's disease, cold increases arterial spasm.
 Allergy or hypersensitivity to cold. Some clients have an
allergy to cold that may be manifested by an
inflammatory response (e.g., erythema, hives, swelling,
joint pain, and occasional muscle spasm). Some react
with a sudden increase in blood pressure, which can be
hazardous if the person is hypersensitive.
which can be hazardous if the person is hypersensitive.
Determine the presence of any conditions
indicating the need for special
precautions during heat and cold therapy:
Neurosensory impairment. Persons with sensory impairment
are unable to perceive that heat is damaging the tissues and
are the risk for burns, or they are unable to prevent tissue
injury
Impaired mental status. Persons who are confused or have an
altered level of consciousness need monitoring and
supervision during applications to ensure safe therapy.
Impaired circulation. Persons with peripheral vascular disease,
diabetes, or congestive heart failure lack the normal ability to
dissipate heat via a blood circulation, which puts them at risk
for tissue damage with heat applications. Cold applications are
contraindicated for these people.
Open wounds. Tissues around the open wound are more
sensitive to Heat and cold.