Environmental Emergencies

Heat/Cold Emergencies

Metabolism runs best at 98.6oF

• T0 - Metabolic rates; cell damage• T0 - Metabolic rates; cell damage

Heat Loss

Conduction

Heat Loss

Convection

Heat Loss

Radiation

Heat Loss

Evaporation

Heat Loss

Respiration

Heat Production1. Metabolism2. Movement of

Large Muscles3. Shivering

Heat Production > Heat Loss = Body Temperature

Heat Loss > Heat Production = Body Temperature

Cold EmergenciesCold Emergencies

Hypothermia Risk Groups

1. Young children & elderly2. Shock patients3. Diabetics4. Head/spinal injury5. Overdose/poisoning6. Homeless7. Burn victims8. Outdoor sports participants

Hypothermia

Generalized cooling of the body Can occur at temperatures above

freezing• Wet clothes• Contact with cold surfaces• Prolonged exposure to the cold

Stages of HypothermiaCore Body Temperature Symptoms

99°F-96°F 37.0°C-35.5°C Shivering.

95°F-91°F 35.5°C-32.7°C Intense shivering, difficulty speaking.

90°F-86°F 32.0°C-30.0°C Shivering decreases and is replaced by strong muscular rigidity. Muscle coordination is affected and erratic or jerky movements are produced. Thinking is less clear, general comprehension is dulled, possible total amnesia. Patient generally is able to maintain the appearance of psychological contact with surroundings.

85°F-81°F 29.4°C-27.2°C Patient becomes irrational, loses contact with environment, and drifts into stuporous state. Muscular rigidity continues. Pulse and respirations are slow and cardiac.

80°F-78°F 26.6°C-20.5°C Patient loses consciousness and does not respond to spoken words. Most reflexes cease to function. Heartbeat slows further before cardiac arrest occurs.

Signs & Symptoms of Hypothermia

Shivering in mild cases (lack of, in more severe cases)

Numbness Stiff or rigid posture Drowsiness or mental status

changes Breathing

• Rapid (early)• Shallow, slow, absent (late)

Blood pressure (low or absent)

Signs & Symptoms of Hypothermia Pulse

• Rapid (early)• Slow and barely palpable (late)

Skin• Red (early)• Pale• Cyanotic• Stiff/hard (late)

Hypothermia Treatment Remove pt. from environment and

prevent further heat loss Remove wet clothing and cover with

blanket Support airway, breathing 100% O2 – warmed/humidified, if possible Handle patient gently

Hypothermia Treatment Do not allow pt. to walk or exert

self If apneic, check pulse 30-45

seconds before starting CPR Do not allow patient to eat or

drink stimulants or smoke Do not massage extremities

Emergency Care ofHypothermiaIf patient is responding appropriately,

rewarm actively: Cover with warm blankets Apply heat to groin, armpits, neck. Warm trunk/torso first. Do not warm too quickly. Increase heat in ambulance. Warm bath if delayed transport.

Emergency Care ofHypothermiaIf patient unresponsive or

responding inappropriately, rewarm passively:

Open airway; provide high-concentration oxygen.

Apply warm blankets. Increase heat in ambulance.

Frostbite Localized cold injury Subfreezing temperatures Vasoconstriction occurs

• Blood flow to distal circulation – usually occurs to nose, ears, fingers, toes

• Water in tissues freezes; tissue damage occurs

Frostbite Signs/Symptoms Mild (frost nip): Red, burning areas Superficial (early): Blanching of the

skin, loss of feeling/sensation Deep (late): white waxy, firm,

cyanotic, possibly blisters and swelling

Local Cold Injury

Emergency Care ofSuperficial (Early) LocalCold Injury Remove patient from environment. Administer oxygen Remove wet/restrictive clothing Protect area from further injury. Splint and cover extremity. Do not rub or massage. Do not re-expose to cold.

Emergency Care of Deep(Late) Local Cold Injury

Remove patient from environment. Protect area from further injury –

cover with dry clothing or dressing Remove jewelry Administer high-concentration

oxygen. Do not:

• Break blisters• Rub or massage area• Apply heat or rewarm• Allow patient to walk on affected

extremity

Passive vs. Active Rewarming Passive

• Allows the body to rewarm itself• Remove wet clothing• Cover with blankets

Active• Application of external heat

sources to patient

For an extremely long or delayed transport (>30 min) active rapid rewarming should be done

Seldom recommended Large potential to permanently

injure frozen tissue

Active Rapid Rewarming of Frozen Parts Immerse the affected part in warm (tepid)

bath water (not to exceed 105°F) NYS

Ensure the water does not cool from the affected part

Continuously stir water Continue until the part is soft and color

and sensation return Dress area with dry, sterile dressings. Protect against refreezing. Expect complaint of severe pain.

Frostbite Treatment Do NOT rub frostbite Do NOT allow refreezing Do NOT allow patient to smoke

Hypothermia can cause apparent Hypothermia can cause apparent absence of vital signsabsence of vital signs

Always resuscitateYou’re not dead until you’re

warm and dead!

Heat IllnessHeat Illness

High Risk Groups Classic Heat Stroke Elderly Chronic medical problems

• Heart Disease• Obesity• Diabetes

High Risk Groups Exertional Heat Stroke Small children in closed

vehicles Athletes, military recruits,

construction workers, on hot humid days

Heat Cramps

Due to salt loss from sweating Spasms in large muscle groups Patient awake, alert

Heat Cramps Treatment

Stop activity Cool environment

Heat Exhaustion Signs, Symptoms

Muscle Cramps Weakness Faintness, dizziness Headache Nausea, vomiting Pale, cool, moist skin Pt. is still sweating therefore body is

trying to cool down

Heat Exhaustion Treatment Stop activity Cool environment Lie down, elevate legs

(trendelenberg) Transport if LOC or symptoms do

not clear rapidly Administer high concentration

oxygen

Heat Stroke Most serious heat-related illness Body temperature > 106oF Damage occurs to temperature

regulating center in brainstem Sweating mechanism fails

Heat Stroke Signs/Symptoms Body temperature Hot, dry, flushed skin Absence of sweating Altered mental status

• Confusion, irritability• LOC• Coma

Seizures Vomiting

Heat Stroke Treatment Remove from hot environment Remove clothing High concentration O2 Assist ventilations as needed Apply cool packs to neck, groin, armpits

(ancillary regions) Keep the skin wet by applying water by

sponge or wet towels Transport immediately