Cold Water Paddling & Hypothermia
Cold water paddling introduces magnificent, wild and challenging worlds to our adventuring. Clouds of new bird species, hundreds of whales, vast and remote wild spaces are open to us with our ability to paddle safely and wisely in cold environments. Sea kayaking began in the cold reaches near the Arctic Circle over 4,000 years ago.
What is the water temperature? Is it raining, windy or cold? How long will I be wet? How long will I be in the wind? Do I have any safety spots? How cold is it for my body? How active am I going to be? What have I recently eaten? How hydrated am I? What is my skill set? The most important skill sets for cold water paddling are effective common sense and reliable judgment. How switched on are you to be out when the margins are small the backup remote.
The Hypothermia Danger: To enjoy cold water paddling we need to avoid hypothermia. Hypothermia occurs simply when the cold challenge of wet, wind, cold overwhelms the body’s ability to produce and to retain heat. Hypothermia can arise from a several minute unpredicted rescue in cold water, from days of rainy, cool conditions, or weeks in a weakened sickly state.
Hypothermia Treatment Theory: The remedy is simple. If prior planning and good judgment fails to avoid the windy, wet, cold challenge, then we need do 3 things:
1. minimize or reverse the cold challenge
2. increase your heat production with exercise, food, water
3. increase heat retention with dry insulation and avoidance of conditions
Cold Shock: Sudden immersion in cold water can create a gasping reflex infusing the inner body with very cold water and accelerating into a severe physiological challenge. Sudden immersion can also trigger immediate fibrillation and cardiac arrest.
Equipping for paddling: The first rule for paddling in cold climates is - dress for the water temperature. Our route selection and clothing needs to protect us from at least two the three primary exposures: cold termperature, windy conditions, wet insulation. (lets not forget the dangers of overheating and exposure to the sun)
- Insulation materials - Synthetic clothing dries quickly and is relatively warm when wet. Cotton + wet + cold Kills, it dries very slowly and evaporative cooling quickens heat loss when wet.
- Layering – Wicking to keep dry layer next to the skin – Polypropylene/polar fleece for insulation, Windproof layer to trap warmth, Waterproof layer to protect insulation.
- Wetsuits, neoprene rubber suits, trap and insulate a layer of water next to the skin. Good for in the water and swimming but cold when wet in the wind. Can be uncomfortable if dry for long periods. Different thickness of neoprene for different level of warmth, one level of warmth per suit = different suit for different season.
- Drysuits afford us a moisture barrier layer to keep our insulation dry and keeps wind out. Add or reduce insulation under the dry suit for temperature control. Good for floating but not for swimming, comfortable in the boat for long paddles. Can be too hot increasing dangers of fluid loss and hyperthermia.
- Extremities must be protected. Protect the head area - protect your thinking, including the throat area with wool/neoprene head gear. Loss of use of hands or feet could prevent us from effecting a rescue, preserving valuable gear or removing ourselves from the cold. Consider poogies or functional gloves for our hands, wet or dry boots for our feet. Consider wool or synthetic materials, and don’t forget your eye protection. “If you have a $10 head, wear a $10 helmet.”
- Emergency/spare clothes are critical equipment components to help change the cold challenge. Needs to protect from temperature, moisture and wind (and sun). How and where do you pack them? How much do you carry?
- What do you carry to lessen being wet, avoid the cold and lessen the wind – to reduce the cold challenge, increase both heat production and heat retention.
The Science of Hypothermia: Our bodies effectively compensate for Earth’s climate and regulate our exercise, food, water and health states to maintain a 98.6 deg core temperature. Its an amazing balance. Mild hypo from 94-98 deg. Severe below 94 deg. Even mild hypothermia requires immediate, speedy and effective treatment now.
When challenged our shell/core effect increasingly reduces blood flow to the skin to reduce heat loss, institutes vaso construction which increases hypoxia of extremeties, induces shivering to produce heat, and implements cold dieresis which dehydrates us.
100% of those hypothermic are dehydrated.
Consider rectal thermometer for evaluation as needed (gives better core temp).
Symptoms: As mild hypothermia sets in we may loss motor skills, have increased muscle rigidity, slurred speech, pale and cool skin, shivering, loss of judgment and changes in mental states: lethargy, withdrawn, confused, irritable, hostile. Our alertness will lessen.
Prevention & Treatment:
- Use common sense.
- Constantly evaluate the risks of the cold challenge.
- Maintain hydration and fuel.
- Pay attention to each other and catch it early. The Umbles
- Help and Huddle.
- Remove from the cold, the wet and the wind as possible.
- Change to dry clothes.
- Apply hypothermia wrap and vapor barrier.
- Evaluate the MOI, the nature of the cold challenge, length of time, depth in body.
Remember the Umbles:
Mumble, fumble, stumble, grumble
Sources: WMA Field Guide, Outward Bound Wilderness First-Aid, Hypothermia & Cold Injuries