The Downtown Boathouse Cold Water Workshop

Highlights, Photos, & Notes on the Cold Water Workshop presented
by the New York Kayak Co. at the Downtown Boathouse, NYC.
Nov. 13, 1999

Notes on Cold water immersion

 Facts and definition

1. Thermally neutral water - 9FF (330C) heat production balances heat loss
2. Hypothermia water temperature <910F, significant hypothermia if T < 770F
3. Risk of hypothermia universal year round in the N. America
4. Problems in cold-water immersion hypothermia and near-drowning

Hypothermia lowering of the body core temperature below the normal level (98.60F), at which normal body functions are impaired.

Recreational activities, including kayaking major source of immersion accidents. Hypothermia claims much more lives than drowning.

 Effects of hypothermia on bodily functions

1. Respiratory system
- initial reflex gasp, followed by fast and deep breathing (hyperventilation) 5
- implications aspiration of water, drowning, confusion, muscle tetany
- significant reduction of under-water breath-holding times decreased survival

- slowing and eventually stopping of breathing

2. Cardio-vascular system release of adrenaline

- peripheral vasoconstriction blood flow to skin and muscles, core
- increase in heart rate and blood pressure first few minutes
- irregular heart beat extrasystole, ventricular fibrillation, sudden cardiac
death (remember, the lower the body temperature, the more likely the arrhythmias
and especially sensitivity of the heart muscle to mechanical stimulation)
- increased urine production up to 350%, risk of hypovolemia, dehydration
- slowing and eventually stopping of the heart

Central nervous system

Tolerance to low oxygen levels and metabolic demands of the body

- progressive depression of mental statu
- moderate hypothermia hallucinations, impaired judgment, disorganized
mental activity panic, fear, loss of will to live
- loss of consciousness at core T < 80-860F (27-300C)

4. Musculo skeletal system
- decreased blood supply to limbs, declining temperature of limbs
- impaired muscle performance - - limb strength, coordination, response time
- inability to swim, stay afloat, pull out of the water, use of signaling devices

Metabolic heat production

After 15 minutes - decline of skin and core temperature.
Skin T<910 F (330 C) shivering - major mechanism of heat production

Heat loss and cooling rate in cold water.