Hypothermia

[rondak100]

I was reading an article about a hiker who died in the White Mts. last week. The article said that he began exhibiting typical hypothermic behavior at some point when he started removing articles of clothing. This baffled me. can anyone confirm and/or explain this behavior.

Mike

[Kevin]

Makes sense, I've heard of this as well...

When the body senses imminent danger it makes that last ditch attmept to warm itself by sending blood to the surface. Doing this makes the person feel like they're burning/on fire, so they remove clothing... but that's really the last thing they should be doing (duh), and they eventually pass out as their core temp lowers to a point they can't function conscious. Eventually, as was the case with that ranger, you die.

I agree that if he were with someone he would have likely survived (maybe turned back sooner, maybe had enough body heat between the two of them to keep the temp that few degrees warmer, who knows...). I refuse to do any agressive winter hiking solo, and have yet to even attempt to hike solo yet. Hiking's more fun (for me) with a person or twelve anyway .

[Trailpatrol]

Oops-Hypothermia

Sorry, I just found the personal message asking me to look at this question.

Part of the answer is that the first thing a hypothermic person looses is their "common sense." A guy I know (A lawyer, avid fly fisherman, and one of my WFA students) admitted that he was having a great day fishing in the Upper Missouri River, and his friends had to literally drag him out of the water, because he had gotten so cold the only thing he could think about was more fish. They tried to convince him to get out, and he wouldn't, so they waded out and brought him in by force.

Mild hypothermia has been termed by some experts as "a case of the umbles": the patient fumbles, grumbles, stumbles and, later, mumbles. Fine motor skills, such as zipping up a parka, decrease. The patient begins to draw inward, becoming less and less sociable. As gross motor skills are affected, a stumbling gait begins. Designed to function optimally at approximately 98.6 degrees F (37 degrees c),the brain will begin to malfunction when its temperature drops below the ideal. In the case of hypothermia, normal thought processes become impaired. Mild hypothermia could be termed "mild stupidity." Patients begin to make poor decisions such as not putting on rain gear when rain begins to fall. Patients typically show increasing confusion and apathy. Mild hypothermia is insidious, affecting the ability of the patient to think, to be aware of its onset, to take care of self. When the brain first senses heat loss is gaining on heat production, it stimulates the primary defense mechanism against further heat loss—vasoconstriction of the peripheral circulation
(shrinking of the blood vessels in the skin). This vasoconstriction dramatically slows blood flowing to the surface of the skin where it will lose heat into the surrounding environment. The lack of blood causes the skin to become pale and cool.

If the core temperature continues to fall, the brain will stimulate the muscles to contract and relax—to shiver—a form of involuntary exercise designed to consume energy and produce heat without requiring voluntary work. An average core temperature at the start of shivering is 95 degrees F (35 degrees c). When shivering starts, the patient enters the realm of moderate hypothermia. In an effort to rewarm, if the core temperature drops further, the brain will increase the intensity of shivering until it becomes violent. A patient will find it increasingly difficult to speak, to walk, to think. Lack of circulation to the surface of the body may cause the skin to turn a duskv color.

The stripping off of clothing occurs in some, but not in every case of hypothermia. It is believed to be more of a panic reaction than a reaction to the cold, because the victim's body is certainly not warm. The brain is getting decreased amounts of oxygen, and is less and less able to function.

Long winded-answer, but since it does not occur all the time, we cannot be sure just what triggers the "strip" reaction. Some survivors report feeling warm, but most don't even remember taking the clothing off. (Medical information is from the Wilderness Medical Institute of NOLS.)

Be safe!
Hans

[Kevin]

Funny that the brain first shrinks the blood vessels. I know I read somewhere that it does eventually try to rush the surface. Obviously, this is later in the hypothermia process than in a 'mild' case.

Either way, this stinks and it's good motivation to carrying a few extra articles of clothes and following the other winter safety tips to keep warm out there!!