NightHiker,
The funny thing is, if someone else had posted this info not too long ago, I too would have disagreed. This information comes from a credible source (Wilderness Medicine Newsletter), and seems to be up to date (2/14/07).


"... The idea that we lose heat faster through our scalp, because of the constant blood supply to the brain, is simply a myth. (One that I personally have believed for many years.)"

Dr. Gordon Giesbrecht, PHD

"On a recent post the practice of using Povidone iodine and/or Betadine on an open wound was discussed and eventually debunked by several knowledgable board members."

At the risk of being somewhat blunt - BS!

Povidone Iodine is one of the most widely used antiseptics in the world. "IF" it slowed cell growth x% so what! It kills ring worm, fungus, sprep and every other commonly known topical organism that causes infection.

I read that article you linked to. And I'm pretty sure that their claims about ingesting cold vs hot fluid to combat hypothermia are going to be debate for a VERY long time, by the majority of people who live were there IS snow. I'm in the same area as the conference they referenced and having lived here most of my life and liking winter, I think they are lacking on that count.

Hot fluids are passive calories. If you doubt that, here is a simple experiment. Take a cold shower. Take your oral temperature. Quickly drink a liter of hot water(chug it if you can). Take your temperature, and again in ten minutes. If taken orally, you'll get a spike for obvious reasons immediately afterwards, but your temperature will climb a few degrees.

It isn't long term, it's a short term effect. And it's probably mostly morale, aka mindset, that is effected. You FEEL warmer, and unlike alcohol, it isn't a trick. I'll stick with warm fluids in winter and cool in summer, thank you.

the hot water thing I"m calling shenanigans on. Your body, from what I remember, needs to heat anything it digests to an accepateble temperature. To do so requires calories. Calories are fuel. Fuel keeps you warm. you"d burn more calories heating something in your stomach, than you would if the temp needs to drop.
Now, I"m not saying I"m right, merely passing on what I"ve learned.

From a fast skimming of this article, it seems that if you are shivering (pretty common in really cold weather if not properly clothed), you can lose over 55% of your body heat from the head. And if not exercising, but have an elevated heart rate due to something like impending panic ("Oh my God, I'm lost in the woods!"), you can lose about 50% of your body heat, again through the noggin. Makes a hat sound good to me...

Alcohol will kill all those things as well but that doesn't make it appropriate to put in a wound.
PI is mostly used to disinfect skin BEFORE surgery not in wounds.
Using diluted PI to irrigate a wound is mainly to sterilize the water not your wound.

Medicine is not static it evolves as the knowledge expands; many former practices are no longer considered appropriate.

The medical "practice" for cleaning and disinfecting wounds has evolved over the years while apparently your medical training has not.

The USCG teaches that one can lose up to 40% of your body heat through your exposed head. This does not mean that you can only lose 10% here and 25% there. It means that if the rest of you are properly clothed except for your head, you can still lose that 40% via your head.

That's why I said hot water. It's already at or above body temperature. I call it "free calories" because you don't need to use calories to heat the fluid.

Then again, I also call my black winter jacket "free calories" because if I go out in the sun it absorbs heat that way rather than having to only rely on body heat to warm the air spaces.

Or are you backing me and I'm just too groggy on cold meds to realise it? :P

Yep. You are transfering the calorie content of the fuel into your body in the form of heat. All other things being equal, a hot cup of cocoa is going to give you more energy than the same cup after it has cooled.

OBG,
Just to clarify, I believe the article says that your head and neck amount to 7% of your bodies surface area, if you are shivering, that 7% sheds 55% more heat raising the actual heat loss from the scalp to about 10% of total body surface area which is the figure the article cites. Then to really confuse the issue, if you start sweating from the shivering, it drops back down to 7%. And yes, a hat still sounds good to me also...