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Ultralight Hikers More Vulnerable to Hypothermia

By Craig & Kathy Copeland, originally published in "Don't Waste Your Time in the Canadian Rockies, the Opinionated Hiking Guide"

We wish we could be truly ultralight hikers. But we've never managed to whittle our pack weight down sufficiently.

For the same reasons we pay to insure our car and home, we carry -- even when dayhiking -- enough gear to ensure we won't succumb to hypothermia should we get lost, injured, or pinned-down by a surprise storm in the backcountry.*

When we see hikers blithely skipping along with only slender hydration packs slung over their shoulders, we're envious. But we know they're carrying little more than water, a sandwich, and maybe a rain shell, which isn't nearly enough to ensure their safety should something go seriously awry.

Imagine you're hiking in the alpine zone. You're 8 mi (12.9 km) from the nearest road. A rock shifts beneath your boot. You stumble, fall, and break your ankle. You're shocked. You can't believe it. You're in pain and cannot walk.

Compounding your predicament, a thunderstorm is brewing. The sky blackens. The clouds drop. It begins raining. The rain turns to hail. The hail turns to sleet. The temperature plummets. You put on your rain shell and huddle against a boulder. But you have no rain pants, no extra insulating layers, and no emergency shelter. You're wet, cold, shivering. Uh oh.

Many deaths outdoors involve only minor injuries, and often no injury at all. "Exposure" is usually cited as the killer, but that's a misleading term. It vaguely refers to conditions that contributed to the death. The actual cause is hypothermia: excessive loss of body heat. It can happen with startling speed, in surprisingly mild weather: often between 0 and 10 C (30 and 50F). Guard against it vigilantly.

Cool temperatures, wetness (perspiration or rain), wind, or fatigue, usually a combination, sap the body of vital warmth. Hypothermia results when heat loss continues to exceed heat gain. Initial symptoms include chills and shivering. Poor coordination, slurred speech, sluggish thinking, and memory loss are next. Intense shivering then decreases while muscular rigidity increases, accompanied by irrationality, incoherence, even hallucinations. Stupor, blue skin, slowed pulse and respiration, and unconsciousness follow. The heartbeat finally becomes erratic until the victim dies.

Avoid becoming hypothermic by wearing synthetic clothing that wicks moisture away from your skin and insulates when wet. Food fuels your internal fire, so bring more than you think you'll need, including several energy bars for emergencies only.

If you can't stay warm and dry, you must escape the wind and rain. Turn back. Keep moving. Eat snacks. Seek shelter. Do it while youre still mentally and physically capable. Watch others in your party for signs of hypothermia. Victims might resist help at first. Trust the symptoms, not the person. Be insistent. Act immediately.

Create the best possible shelter for the victim. Take off his wet clothes and replace them with dry ones. Insulate him from the ground. Provide warmth. A pre-warmed sleeping bag inside a tent is ideal. If necessary, add more warmth by taking off your clothes and crawling into the bag with the victim. Build a fire. Keep the victim conscious. Feed him sweets. Carbohydrates quickly convert to heat and energy. In advanced cases, victims should not drink hot liquids.

*When dayhiking, we always pack a 5-ounce, sil-nylon tarp that we can use to quickly erect a shelter big enough to cover us both. Each of us also carries a small, bum pad made of closed-cell foam, and a waterproof, breathable, SOL Escape bivvy sack that weighs only 8 ounces. These, plus a waterfproof shell and pants, insulating hat and gloves, midweight fleece tights, and an expedition-weight fleece top, comprise an effective yet reasonably light, compact, insurance policy against hypothermia. Total weight: approximately 3.5 lbs per person.