A quick guide on hypothermia and how to treat it.
By: Alan Halcon and Dude Mclean
What, an article about hypothermia in the spring? Sure why not. It really
doesn’t need to be freezing to find yourself in trouble. The big chill can move
in on you, or someone with you—recognizing the signs and knowing how to
properly treat hypothermia can mean the difference between living and dying.
How You Lose Heat to the Environment
Heat always transfers to cold, and it is important to know the four factors
surrounding this phenomenon.
Radiation - loss of heat due to the temperature difference. This
occurs as long as the ambient temperature is below our bodies 98.6 degrees
Fahrenheit.
An example of radiation is the suns heat; one can feel the warmth radiating
from the sun. Another example is the warmth felt from a campfire.
Conduction – is the loss of heat through direct contact between
objects
An example of conduction is sitting on a cold rock and feeling your butt get
cold. Wet clothes coming in contact with your body is another example of loss
through conduction.
Convection – is heat loss due to the movement of air or liquid
across your skin. The warmer body temperature is carried away and replaced by
the cooler air or liquid. Losing heat via water convection occurs more quickly
than air convection. An example of air convection is Wind Chill. An example of
liquid convection is taking a cold shower or falling in cold water.
Evaporation - heat loss occurring by converting water to vapor
An example of evaporation is the body’s perspiration being cooled at the skins
surface.
Evaporation can be responsible for 20-30 percent of heat loss even in temperate
conditions. In addition, a non-active person loses approximately 15 percent of
his average daily caloric intake through evaporation.
How Your Body Regulates Core Temperature
Vasoconstriction – is the constriction of blood vessels.
Vasodilatation – is the dilatation of the blood vessels
Sweating - cools body through evaporative cooling
Shivering - generates heat through increase in muscle activity. This is limited
because of depletion of muscle glucose and fatigue.
Signs and Symptoms of Hypothermia
Any temperature less than 98.6 degrees is linked to hypothermia
In their book “Hypothermia Frostbite and other Cold Injuries” authors Gordon G.
Giesbrecht, Ph.d, and Doctor, James A. Wilkerson, write “A mnemonic useful for
remembering the early stages of hypothermia is “umbles.” The mildly hypothermic
individual: fumbles, stumbles, tumbles, mumbles, and grumbles. The first three
items (fumbles, stumbles, tumbles) reflect impairment of motor function, first
fine movements and then gross movements. The last two (mumbles and grumbles)
indicates intellectual impairment.”
Mild Hypothermia
Normal shivering can begin
Cold sensation and goose bumps
not able to perform complex tasks with hands
shivering can be mild to severe
hands are numb
Moderate Hypothermia
Shivering is intense
obvious lack of muscle coordination
movements are slow and labored
mild confusion, but may appear alert
violent shivering continues
has difficulty speaking
is sluggish in thinking
amnesia begins to appear
gross muscle movements are sluggish
not able to use hands
stumbling is frequent
has difficult time speaking
depressed and withdrawn.
Severe Hypothermia
All shivering stops
exposed skin becomes blue or puffy
muscle coordination is very poor
not able to walk
appears confused
behavior is incoherent and irrational, but may be able to maintain awareness
Muscle stiffness
semiconscious
in a stupor
a loss of awareness of others
pulse and respiration rate decrease
possible heart fibrillation
unconscious
heart beat and respiration are erratic
pulse may not be palpable
Pulmonary edema
cardiac and respiratory failure
How to determine if someone is suffering from hypothermia
If shivering can be stopped voluntarily the person is suffering mild
hypothermia
Ask a question that requires higher reasoning in the brain; e.g. say the
alphabet backwards. If the person is hypothermic, they won't be able to do it.
If shivering cannot be stopped voluntarily the person may be suffering from
moderate to severe hypothermia
If the person is unable to walk a 30 foot straight line, the person is
hypothermic.
Treating Hypothermia
It is extremely critical to properly treat a person who is suffering with
moderate to severe hypothermia. Failure to properly treat can result in death
There are a few DO NOT DOs one should stick by when treating a person with
hypothermia
* Never give alcohol to the victim. Alcohol is a vasodilator and will
increase peripheral heat loss
* Never give caffeine to the victim. Caffeine is a diuretic and causes
water loss increasing dehydration
* Never allow a victim to smoke. Tobacco/nicotine is a vasoconstrictor and
increases the risk of frostbite.
* Never allow a victim to self-help if they are suffering from moderate to
severe hypothermia.
* Never and I mean never massage or rub a persons extremities (hands,
arms, legs, feet) to get the blood circulating. Doing so can cause a
condition called after-drop* and kill the victim.
Treatment Mild Hypothermia
Add more layers of dry clothing
Increase physical activity
get person out of elements
build fire to warm person
increase caloric intake by eating foods with simple sugars. (breads, candy
bars, warm water with honey or sugar, etc.
Moderate to Severe Hypothermia
Get person out of elements
Be very gentle with the victim a hypothermic person’s heart is hyper excitable
and can lead to arrhythmia
The victim should lay down in the horizontal position
Do not elevate the victims arms or legs while the person is laying down;
After-drop can occur.
Apply warm compresses: under both armpits, the groin, and back of the neck.
Give victim warm water with sugar*
If necessary, use hypothermia wrap*
Make sure person heart rate is not present before administering CPR*
After-drop Is where the core temperature actually decreases during re-warming.
After-drop occurs by peripheral vessels in extremities dilating if they are
re-warmed by external heat sources, rubbing, or massaging. This causes the very
cold blood from the extremities to move back to the core. This further
decreases the core temperature, and can lead to death. Moreover, this blood is
acetic which can lead to cardiac arrhythmias and even death… Re-warm the core
only!
Hypothermia Wrap: Make sure the patient is dry. The person must be
protected from any moisture in the environment, including a layer to keep the
victim from collecting sweat on the skin. Use multiple sleeping bags, wool
blankets, wool clothing. 4" of insulation should be all the way around the
patient, especially between the patient and the ground to prevent heat loss due
to conduction. Include a Mylar "space" blanket to help prevent
radiant heat loss. Wrap the entire thing in plastic to protect from wind and
water.
Warm Sugar Water: people with severe hypothermia will not be able to digest
solid food; however, they can absorb water and sugars. Giving a diluted mixture
of warm water with sugar/Jell-O every 15 minutes will allow the victims
metabolism to kick in and generate internal heat.
Urination Urinating will help conserve heat. A full bladder uses body heat to
keep urine warm rather than vital organs. Once the person has urinated, body
heat will be redirected towards vital organs. You will need to help the person
urinate. Open up the Hypothermia Wrap enough to do this and then cover them
back up.
CPR a person in severe hypothermia may demonstrate all the clinical signs of
death, but they may still be alive and can be revived. During severe hypothermia
the heart is hyper excitable and administering CPR can result in fibrillation
and death.
Be sure the pulse is completely absent before beginning CPR. Remember, the
heart rate may be 2-3/minutes apart and the breathing rate 1/30 seconds.
Administering CPR at this point may lead to life-threatening arrhythmias. Check
the carotid pulse for a longer time period (up to a minute) to ascertain if
there is some slow heartbeat. A hypothermia victim is never dead until warm and
dead. If there is no discernible heartbeat begin CPR, and be prepared to
continue - persons with hypothermia have been given CPR for up to 3.5 hours and
have recovered with no neurological damage.
It’s really up to you!
Basic first-aid is often overlooked by even the most experienced outdoorsmen—Red
Cross courses
are available across the country. All it takes is a little effort
to help save a life. Hypothermia is one of the most common medical emergencies
one will encounter in the outdoors. Knowing how to recognize and treat
hypothermia, until professional help arrives, should be a part of your skill
set.