Hypothermia
Introduction:
- Hypothermia occurs when the body’s temperature drops by at least 2°C after immersion in cold water.
Signs and Symptoms:
- Early dulling of sensation, violent shivering, blueness around lips, cold armpits, muscle stiffness, lethargy, disorientation, slow breathing, weak pulse.
Dangers:
- Risks include impaired sensation and muscle coordination, loss of consciousness, drowning, cardiac arrest, and death.
Prevention and Survival:
- Wear approved lifejackets and immersion suits over warm clothing. Learn cold-water survival techniques (e.g., “HELP” position). Exit the water as soon as possible using a life raft or any available refuge.
Final Notes:
- Do Not Assume a Person is Dead: They may be in a state resembling hibernation. Immediate medical attention is crucial.
Immediate Actions for Hypothermia Victims
Prevent Further Heat Loss:
- Enclose in Waterproof Material: Place the victim in a plastic bag or similar material.
- Insulate the Body: Cover the victim, paying particular attention to the head.
- Remove Wet Clothing: If dry replacements are available, change the victim’s wet clothes. If not, enclose the body (except the face) in a large plastic bag or other waterproof material.
Monitor Vital Signs:
- Continuously check the victim’s airway, breathing, and circulation.
Shelter and Position:
- Move the victim to a sheltered area and place them flat.
Provide Warm Fluids:
- If the victim is conscious, offer warm, sweet drinks. Avoid alcohol.
Avoid Rubbing:
- Do not rub the victim’s body as this can worsen heat loss and cause tissue damage.
Key Facts About Hypothermia
Rapid Cooling in Water:
- In cold water, vital organ temperatures can drop in 15 to 30 minutes. Skin and muscle temperatures fall faster, which impairs early lifesaving actions.
Swimming and Cooling:
- Swimming may feel warm but accelerates muscle cooling, making it harder to survive as body heat is lost rapidly.
Children vs. Adults:
- Children cool faster due to their smaller size and lower body fat. Boys typically cool faster than girls.
Clothing in Water:
- Normal clothing offers minimal insulation in cold water but can slow heat loss. Lifejackets, immersion suits, and well-fitting wetsuits significantly reduce hypothermia risk for water sports enthusiasts.
Conservation of Heat in Water
Avoid Swimming:
- If possible, avoid swimming. Floating or treading water conserves energy and heat.
Use of Clothing:
- Clothes help slow heat loss.
Immersion Suits:
- Wet suits provide buoyancy and reduce heat loss for some time. Dry suits are better for long-term survival. Floatation aids such a Mullion Flotation Devices
Use Floating Objects:
- Use floating objects like swamped or capsized boats to keep as much of the body out of the water as possible.
H.E.L.P. Position:
- Adopt the Heat Escape Lessening Position (legs together, elbows at sides) if wearing a buoyancy aid to slow heat loss in calm water.
Cold Shock
Introduction:
- Cold Shock occurs with sudden immersion in cold water (<15°C) and can incapacitate and lead to drowning within the first 2-3 minutes.
Signs and Symptoms:
- Deep gasping, uncontrollable rapid breathing, dizziness, panic, increased heart rate and blood pressure.
Prevention:
- Use man-overboard prevention equipment, wear approved lifejackets, and use well-insulated clothing. Hold onto support and avoid swimming until symptoms subside.
Follow-Up Actions:
- Monitor airway, breathing, and circulation. Prevent further heat loss, protect from wind, and seek medical help.
Dangers:
- Risks include water inhalation, drowning, stroke or heart attack.
