A year later, I finally write my response to Skater's post. <img src="/images/graemlins/crazy.gif" alt="" />I tried this after reading this post last year. It kept my head toasty warm! I did it occasionally, but only on very cold days. Sometimes, I just wanted it a tad cooler.

As for hypothermia, I don't know how important the head is versus the body. Speaking purely from a common-sense perspective (always worth some healthy skepticism in the medical arena), I myself can only assume that anything that keeps any part of you warm(er) must be at least partially helpful in contesting hypothermia. Does anyone have anything worth adding regarding that?

Stay safe,
J.T.

>>As for hypothermia, I don't know how important the head is versus the body.<<

Vastly. Huge importance. Critical.

And much more so than any other "appendage". The body reacts to cold by quickly cutting down the blood flow to limbs (especially the surface where heat dissipates) and even organs, and can make LARGE adjustments to heat loss by doing so, will even sacrifice appendages (toes lost to frostbite) if it has to, but it CANNOT restrict blood to the brain for obvious reasons. This is such a critical factor that we not only still have a mat of fur on our heads to help regulate heat loss, but it can be grown to any length... and odd development, when you think about it.

In some spectral ranges of infra-red, people wearing down jackets in the cold look like matches with their heads alight- the amount of heat leaving from the head is amazing. Same applies to a head sticking out of a sleeping bag.

I always carry a lightweight balaclava when camping; it makes more difference to sleeping well in the cold than a LOT more weight in a sleeping bag.

When ambient temperature raises significantly above blood temperature, things reverse, and the insulation (hat, cap, hair) actually helps keep the head cooler than surroundings. Having the surface that the sun beats on as far away from the brain as possible helps too, hence sombreros and ten-gallon hats with high crowns.

JFK refused to wear the traditional Homburg hat to his inauguration, starting a fashion stampede away from hats. Actors suddenly found that their faces were much more visible on movie screens without hats, and, since Hollywood dictates style, and then the car makers immediately took advantage of the trend to lower their roofs (and costs) there was no going back from there... but it's a huge disservice to those who go outdoors. Real outdoorsmen wear hats, or at least have one (or more) in their kits. Properly used (take it OFF when you start to get hot, out of the sun), a hat can make amazing adjustments to your comfort level and safety- there's a reason men have worn them for at lest several thousand years. The lack of one can certainly kill you in the desert, and might make the difference between life and death in the cold.

Thanks for the tip about the mylar in a hat- I hadn't thought of that, and at the risk of comments about geeks and tinfoil beenies, I might play with the idea a bit. Tilly hats have this convenient little pocket in the crown...

It keeps the aliens from reading your thoughts too. <img src="/images/graemlins/grin.gif" alt="" /> Sorry... couldn't resist. What was that movie anyway? Was it the one with Mel Gibson as the preacher/farmer?

"Signs". Thought it was a great movie. Pete

Keep in mind that the current thinking on fish hook removal has changed with time. Today the usual recommendation is to try to back the hook out while pressing away from the barb rather than push it all the way through.

Here is a good overview:
http://www.aafp.org/afp/20010601/2231.html

KenK, thanks for the link, very well illustrated. All my hook removals involved wire cutters (soaked in alcohol) and cutting the hook end off and sometimes the eye as well, then pulling the rest thru.

Jet, thanks for your input, as well as PLs.
I have always been under the impression that the head is the major point for body heat loss.
I was a bit surprised that I did not get a response to the question, but I also thought it would be appropriate to include it in the treatment of hypothermia.
The idea of using a watch cap with a piece of space blanket inside seems pretty logical.
Again, thanks for your response.

I've spent a fair amount of time avoiding hypothermia, but I'm not qualified to say much about treating it. There are different stages, and at the stages where the body is just losing heat faster than it can generate it, anything will help- insulation, reflection, shelter.

My understanding, though, is that at later stages the actual capability of the body to generate heat is compromised, and it becomes much more difficult for the patient to recover just using mechanisms that work by retaining that body heat. If that's all you've got, then you do what you can, but the medical advice I've seen for severe hypothermia always seems to emphasize external sources of heat, as fast as possible (short of scalding/burning, of course).

But, as I say, I have no expertise in that area. Maybe adding to the subject line will counteract the thread drift and attract attention from those who do.

It's amazing how many facets of survival are just thermodynamics in disguise. If it weren't for the need to keep body heat up, we wouldn't be concerned about clothing, sleeping bags, tents and shelter, rain gear, making fires... almost everything we talk about is directly or indirectly about heat flow.

Skater,

Check out these web sites, as they have a lot of excellent information :

http://www.hypothermia.org/hypothermia.htm

http://www.wemsi.org/
http://www.wemsi.org/alg.html
http://www.wemsi.org/hypotherm_bfr.html


Pete

I agree it was a good movie, except for one thing ... if the aliens could not be exposed to water, WHY did they come to a planet that is virtually covered with the stuff? Just me ...