thermogenesis
Increased body temperature causes increase heat loss and shut off normal heat production pathways.
thermolysis
Decrease body temperature prompts heat production and conservation and turns off normal heat-liberating pathways.
conduction
Transfer of heat from body part to a colder object or substance by direct contact.
convection
Heat is transferred to circulating air
evaporation
Body sweats to cool itself
radiation
Loss of body heat directly to colder object in the environment by radiant energy.
respiration
Body heat loss as warm air in the lungs is exhaled into the atmosphere and cooler air is inhaled.
To protect itself against heat loss, the body :
Constricts blood vessels in skin
Creates heat by shivering
s/s mild hypothermia
Core temp 93-95 degrees Alert, withdrawn, anxious, or restless Shivering Tachycardia Tachypnea Skin may be red, pale, cyanotic
s/s moderate hypothermia
Core temp 89-92 AMS Poor coordination and memory loss Loss of sensation to touch, mood changes, and impaired judgement Difficulty speaking May appear stiff or rigid
s/s severe hypothermia
Core temp below 80 Vital signs low Unresponsive Pulse weakens Respiration decrease or become absent Cardiac dysrhythmias Pupillary reaction slow May appear dead Cardiac arrest
frostnip
Skin may freeze from prolonged exposure, but the deeper tissues are unaffected.
signs of frostnip and immersion foot
Skin is pale and cold to touch
Nl color returns after palpitation of skin
signs of frostbite
hard, waxy feel
blisters and welling
General emergency treatment of cold injuries
Remove pt from further exposure
Handle the injured part gently and protect it
Administer oxygen
Remove any wet or restrictive clothing over injured part
Frostnip emergency care
Contact with a warm object - hands, breath, or pt’s own body
Immersion foot emergency care
Remove wet shoes, boots, and socks
Rewarm foot gradually and protect from cold
Splint extremity and cover loosely w/ dry, sterile dressing
Frostbite emergency care
Remove restrictive items from injured part
Cover injury loosely w/ dry, sterile dressing
Do not apply heat or rewarm
Do not allow pt to stand or walk on frostbitten foot
Splint extremity
Support vital signs
Prompt transport
s/s of heat exhaustion
Cold, clammy skin w/ ashen pallor Dry tongue and thirst Dizziness, weakness, or faintness Headache Nausea Tachycardia Hypotension Nl or slightly elevated temp
s/s heatstroke
AMS Delirium Seizures Dry, hot skin. Diaphoresis may persist. No muscle cramps Increased RR Tachycardia - bradycardia, weak
Managing heat cramps
Remove pt from environment
Loosen any tight clothing
Administer high-flow oxygen if indicated
Rest cramping muscles
Replace fluids by mouth
Cool pt w/ cool water and add convection method of cooling
–Establish IV and transport to hospital if cramps do not improve
Treating heat exhaustion
Remove pt from environment
Remove excess clothing
Administer oxygen if indicated
Check BS if altered
Cool w/ misting and ice packs to trunk.
Ice bath or similar facility if available.
Supine position
Convection cooling method
Slowly drink up to 1 liter of water if alert
IV access - administer saline fluid boluses of 20 mL/kg as needed
When should you transport the pt to a hospital for heat exhaustion?
Sxs do not clear up promptly
LOC decreases
Body temperature remains elevated
Person is very young, older, or underlying medical condition
Managing heatstroke
Remove pt from environment into ambulance Set air conditioning to max Remove clothing Administer high-flow oxygen if indicated Cold-water immersion if possible Cover pt in wet towels or sheets, or spray w/ cool water and fan Aggressively and repeatedly fan pt R/o other causes of AMS Check BS Rapid transport Notify hospital ASAP
What should you do if cold-water immersion is available, but you are unable to cool en route?
Continue cold-water immersion at the scene until body temp is between 101-102
