Cold Injuries

Cold injuries First aid and treatment

Definitions • Normal temperature around 37° degrees C • Hypothermia mild 32 -35° C moderate 28 -32° C severe less than 28° C 26° degrees ……

Thermoregulation • Peripheral receptors in the skin mostly detect changes in the ambient temperature • Central receptors detect changes in the blood and the core of the body • Central and peripheral signals travel to the temperature regulation control centre in hypothalamus

How can the body prevent hypothermi???? • Shivering can increase heat production • Shivering is an unsynchronised highfrequenty muscular contraction combined with a slow, synchronised, centrally triggered muscular contraction

Accidents - events • • • •

Drowned Persons under influence of alcohol Psychiatric disorders or dementia Outdoor enthusiasts in cold water stranded or lost in cold and windy weather injuried in cold weather

Psychological heat loss • Vasoconstriction in blood vessels in hands and feet • The head blood vessels are protected Heat can escape from the head!!! Heat loss from respiratory tract too.

Drowning • Critical watertemperature • Metabolism • Heat production Unpredictable circumstances – survivers Fear ….. breathing Unconsciousness Turbulent waves Aspiration

Wind effects • Wind increase the risk of hypothermia and frostbite • Even low wind accelerate the rate of heat loss • Example: -10 C combined with a wind strengh of 15 m/sec correspond -33 C

What happens in the body? • The nervous system • The circulatory system arrythmias blood vessels • The coagulation system • The respiratory system • Renal function and fluid balance

Clinical picture • Early, vague symptoms like hunger, silence, fatigue, bad temper, lack of co-ordination and confusion • The degree of consciousness gradually declines, between 30° C -26° C people will get unconsciousness • The skin turns to cold an pale, especially the extremities. • The pulse will be faint • Pupils become fixed • Shivering stops at about 33° C

Mental changes • • • • • • • • •

Early anxiety Poor judgement Neurotic behaviour Disturbed perception of reality Describe the situation in a different way Apathy Hallucinations Psychosis Receptor disturbance in the heat control centre

First aid • Try to get shelter • Sweetened hot drink • Handle the patient with care and avoid sudden movements - think of the heart • Remove wet clothing (depends on) • Cover the head warmly • Insulate with warm blankets – extra to head an feet

Treatment • Warm very carefully - slowly

• Gently transportation - horizontal position

Hospital care • • • • •

A - Airway management B - Breathing (ventilation) C – Circulation D – Disability (level of consciousness) E – Exposure and environmental control, Degrees and Dry