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City of Orono, Minnesota
The Lakeshore City


Remember, hypothermia is the number one killer of outdoor recreationalists in the United States.

What is Hypothermia?

When exposed to cold temperatures, your body begins to loose heat faster than it can be produced.  The result is hypothermia, or abnormally low body temperature.  Body temperature that is too low affects the brain, making the victim unable to think clearly or move well.  This makes hypothermia particularly dangerous because a person may not know it is happening and won't be able to do anything about it.

Hypothermia occurs most commonly at very cold environmental temperatures, but can occur even at cool temperatures (above
40º F) if a person becomes chilled from rain, sweat, or submersion in cold water.

What are the Warning Signs of Hypothermia?

Mild Hypothermia -

Shivering - not under voluntary control 

Can't do complex motor functions (ice climbing or skiing), can still walk and talk

Vasoconstriction to periphery

Moderate Hypothermia -

Dazed consciousness

Loss of fine motor coordination - particularly in hands - can't zip up parka due to restricted peripheral blood flow  

Slurred speech

Violent shivering

Irrational behavior - paradoxical undressing - person starts to take off clothing, unaware she/he is cold 

"I don't care attitude" - flattened affect

Severe Hypothermia -

Shivering occurs in waves, violent then pause, pauses get longer until shivering finally ceases

Person falls to the ground, can't walk, curls up into a fetal position to conserve heat

Muscle rigidity develops

Skin is pale

Pupils dilate

Pulse rate decreases  

At 90 degrees the body tries to move into hibernation, shutting down all peripheral blood flow and reducing breathing rate and heart rate

At 86 degrees the body is in a state of "metabolic icebox." The person looks dead but is still alive

First Aid Tips - To Help Victim Who Has Fallen Through Ice & May Have Hypothermia

First aid for hypothermia requires warming the victim and removing any wet clothing.  Here are some basic steps to follow:

Get victim out of water if possible.  SEND SOMEONE FOR HELP & CALL 9-1-1.

After victim is out of the water, make sure he/she is breathing and has a pulse.  If not, start CPR.

Get victim to warmth-preferably, indoors.  BUT DON'T WASTE TIME.  A car, or fish house will do - anywhere out of the wind and weather.

Once in a warm spot, replace wet clothing with dry ones, or wrap victim in blankets, etc.

If victim is semi-conscious or worse, try to keep him/her awake. 

Keep the head tilted back to insure an open air passage. 

In all cases get the victim to competent medical attention as soon as possible.

і CDC Website, "National Center for Environmental Health" Extreme Cold, Frequently Asked Questions. 

і Princeton Ed Website, "Princeton Education" Outdoor Action Guide to Hypothermia & Cold Weather Injuries.



City of Orono, 2750 Kelley Parkway, Orono, MN 55356 - Main (952) 249-4600 - Fax (952) 249-4616