Saturday, March 31, 2007

Hypothermia

Several years ago, about this point in spring, I got hypothermic on a hike. I made it out okay but the incident was definitely a wakeup call, things might easily have turned out badly.

I headed to the local west side of the Cascades at a fairly low elevation for an early hike. It was warm and mostly sunny in the lowlands, at the trailhead it was cloudy and spitting some rain. The trail was badly obstructed with blowdowns and to make progress I literally needed to crawl through trees. After about an hour, I decided to give up, it was beginning to snow and hiking wasn't at all fun, just a succession of obstacles. Some amount of time later I made it back to my pickup and was surprised at the difficulty I had in getting my keys out and unlocking the pickup; my hands were very cold and stiff. Why hadn't I noticed and put on gloves? Fortunately the pickup was parked so the windshield faced what sun there was, it was probably 20 degrees warmer inside than out. As I usually do after a hike, I poured a cup of coffee, using the cup to warm my hands, and ate some candy. Shortly thereafter I started feeling very cold and then started to shiver. At that point I started coming out of my half daze and pulled off wet clothing and pulled on a wool sweater and cap, both were in my daypack but I hadn't been cold before. After I warmed up enough to safely drive, I went home, with my heater on full blast. At home I changed into warm, dry clothing, everything I was wearing was wet, including innermost garments, and had some soup. Then I crawled into bed, still feeling cold, and slept for 2 hours when I was finally warm, although still tired.

Before I went hiking again, I thought long and hard about what had happened. I was alone, if I had fallen, easy to do on the wet, tangled wood I crawled through, I might not have made it out. Obviously I couldn't rely on feeling cold or shivering to warn me of approaching hypothermia, I didn't remember feeling cold until after I started to warm up. And the temperature wasn't that cold, probably above 30 F the entire time. The extreme tiredness was also worrisome, luckily I had planned on going home afterward.

The first thing I did was replace my old and battered Goretex shell, it was no longer keeping me dry. At the same time I bought a new shell, I picked up some lightweight rain pants. I also noticed that even though in a daze, I followed my usual hiking practices (SOP). I needed to add some rules to my hiking SOP to hopefully avoid this problem in the future. I wasn't wearing much cotton, mixed polyester/cotton pants, and a tee-shirt but everything else was wool or polyester (see here). However I needed an additional or heavier layer on top. So I started wearing a midweight top over a lightweight top in similar conditions with at least a sweater in my pack. I also made the rule that in cold weather, after going up for a while, when I started down for a stretch, I needed to put on another layer. No thinking if I'm cold, just do it. Also, I need to eat more often, at least every 2 hours and preferably more frequently and drink more often, every few minutes. At least part of my problem was exacerbated by low blood sugar and dehydration, ridiculous given the wetness of the hike.

I've done a lot of hiking in similar conditions since without any problem. I continue to remember this episode and what I learned. I was very lucky that I learned this lesson without serious consequences. In the last few years, I've read about a number of people who weren't so fortunate.

Labels:

2 Comments:

At 31/3/07 21:42, Blogger Mossy Mom said...

I often get cold on my hikes and I don't fully warm up until I have been back at home for an hour. I usually keep a hot thermos of something in the car and I bring a little acohol stove along so I can make hot tea on the trail.

I wish the heater in my car was better, that would be a big help.

Today I had hot tea on the trail but still I did not fully warm up until I had been home for a while.

 
At 1/4/07 15:07, Blogger feralhiker said...

Sometimes I feel a little cold on hikes and don't warm up immedidiately also. I do try to carefully differenciate between a little cold and cold. What I'm going to do afterwards makes a difference. If I'm going to camp, I try not to be cold, it is too hard to warm up.

In cold weather I often carry a pint thermos with hot, sweet tea. Very good to warm my hands.

 

Post a Comment

<< Home