CHAPTER 22 Environmental Emergencies. Temperature Regulation

CHAPTER 22

Environmental Emergencies

TemperatureTemperatureRegulationRegulation

The body tries to balance heat loss and heat gain to maintain normal temperature.

Exposure to ColdExposure to Cold

If heat loss If heat loss exceeds heatexceeds heatgain, hypothermia gain, hypothermia (low body (low body temperature) temperature) occurs.occurs.

The body loses heat in 5 ways:

Conduction

Convection

Radiation

Evaporation

Respiration

Heat Loss

Heat Loss fromHeat Loss fromconductionconduction, which, whichis the transfer of is the transfer of heat from one heat from one material to anothermaterial to anotherthrough direct through direct contact.contact.

Heat Loss fromHeat Loss fromconvectionconvection, which, whichis when currentsis when currentsof air or water passof air or water passover the body,over the body,carrying away heat.carrying away heat.

Heat Loss from Heat Loss from radiationradiation, which is , which is sending out energy, such as heat, in sending out energy, such as heat, in

waves into space.waves into space.

Heat Loss fromHeat Loss fromevaporationevaporation, which , which is the change fromis the change fromliquid to gas. When liquid to gas. When the body gets wet,the body gets wet,evaporation of the evaporation of the perspiration or otherperspiration or otherliquid into the airliquid into the airhas a cooling effecthas a cooling effecton the body.on the body.

Heat Loss fromHeat Loss fromrespirationrespiration, which, whichis breathing. Duringis breathing. Duringrespiration, body respiration, body heat is lost as warmheat is lost as warmair is exhaled fromair is exhaled fromthe body.the body.

One should be aware of methods of heat loss when treating patients with hypothermia to prevent further heat loss. Have blankets, heat packs, and a warm ambulance ready for your patient.

Questions to ask????

Source

Environment

Loss of consciousness

Effects

General

Local

Generalized Hypothermia

Predisposing Factors

Cold Environment

Cold water immersion

Cold air exposure

Age – Very Old

Failing body systems

Chronic illness

Lack of exercise

Certain medications

Low/fixed incomes



Age – Very Young

Large skin surface area

Less body fat

Small muscle mass, so little or no shivering

Inability to put on or take off clothing




Medical Conditions

Shock (hypoperfusion)

Head/Spinal cord injury

Burns

Generalized infection

Diabetes and hypoglycemia

Drugs and poisons

PredisposingFactors

Signs & Symptoms ofHypothermia

Environmental conditions of cold exposure

Obvious exposure (patient found in snow, ice water)

Subtle exposure

Ethanol ingestion

Underlying illness

Overdose/poisoning

Major Trauma

Outdoor Resuscitation

Ambient temperature decreased (home of the elderly patient)


Cool/Cold Skin Temperature

Place the back of your hand between the clothing and the patient’s abdomen to assess the general temperature of the patient. The patient experiencing a generalized cold emergency will present with cool abdominal skin temperature


Decreasing mental status or motor function

Poor coordination

Memory disturbances

Reduced or loss of sensation – to touch

Mood changes

Less communicative

Dizziness

Speech difficulty

Stiff or rigid posture

Muscle rigidityShivering may be present or absentBreathing changes

Rapid (early)

Shallow, slow, absent (late)

Slowly responding pupils


Continued…

Pulse changes

Rapid (early)

Slow, weak, irregular, absent (late)

Low to absent blood pressure

Poor judgment – may remove clothing

Complaints of Muscle and joint stiffness


Skin

Red (early)

Pale

Cyanotic

Stiff/hard (late)


Stages of Hypothermia

Core 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-87°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.

Emergency Care of Hypothermia

Remove patient from environment and prevent further heat loss.

Remove wet clothing and cover with blanket – keep the patient dry.

Handle patient gently. Avoid rough handling.

Continued…

Emergency Care ofHypothermia

Do not allow patient to walk or exert self.

Give high-concentration oxygen (warmed and humidified).

If apneic, check pulse 30-45 seconds before starting CPR.

Continued…


If patient is responding appropriately, rewarm actively – DO NOT WARM TOO

QUICKLY!!!:Warm blankets Warm blankets

Apply heat to groin, armpits, neck. Warm trunk first.

Do not warm too quickly.

Increase heat in ambulance.

Warm bath if delayed transport.

Continued…


If patient unresponsive or responding inappropriately, rewarm passively:

Apply blankets.

Increase heat in ambulance.

Transport.


Do not allow patient to eat or drink stimulants or alcohol.

Do not massage extremities – it damages the underlying tissues due to the formation of ice crystals.

Be prepared for cardiac arrest, have the defibrillator ready.

Transport patient.

Continued…


Usually occurs in extremities and exposed ears, nose, face, fingers. When body part is exposed to cold, blood vessels constrict which limits blood flow. Tissues then freeze and ice crystals can form – in severe cases gangrene (tissue death can occur)

Localized Cold Injuries

Local injury with Local injury with clear boundaryclear boundaryseparates injured/ separates injured/ uninjured areasuninjured areas

Signs & Symptoms ofSuperficial (Early) LocalCold Injury - Frostnip

Blanching of skin – palpation of the skin in which normal color does not return (reddens first in light skinned/ dark skin lightens)

Loss of feeling and sensation in affected area

Skin remains soft

When rewarmed, area tingles

Signs & Symptoms ofDeep (Late) Local Cold Injury

Also known as frostbite – develops if the early/superficial local cold injury goes untreated.

White, waxy skin

Firm to frozen feeling upon palpation

Swelling and blisters may occur

If thawed or partially thawed, the skin may appear blotchy, mottled, or grayish yellow or blue

Emergency Care ofLocal Cold Injury

Remove patient from environment.

Protect area from further injury.

Administer oxygen (warmed and humidified if possible) and care for shock.

Remove wet or restrictive clothing.

Emergency Care ofSuperficial (Early) LocalCold Injury

Splint extremity

Cover the extremity

Do not rub or massage.

Do not re-expose to the cold.

Local Cold InjuryLocal Cold Injury

Remove jewelry.

Cover with dry clothing or dressings and warm blankets.

Keep the patient still and handle gently.

Emergency Care of Deep(Late) Local Cold Injury

Do not:

Break blisters

Rub or massage area

Apply heat

Rewarm

Allow patient to walk on affected extremity

Rub with snow

Emergency Care of Deep(Late) Local Cold Injury

Passive vs. Active Rewarming

Passive

Allows body to rewarm itself.

Remove wet clothing.

Cover with blanket(s).

Active

Application of external heat sources

to patient.

Central Rewarming

Central

Application of heat sources

lateral chest

neck

armpits

groin

Active Rewarming of FrozenParts

Seldom recommended

Perform only if:

Transport extremely delayed AND

Medical control orders it OR

Protocols allow it

Large potential to permanently injure frozen tissue

Be careful not to rewarm too quickly

Immerse the affected part in warm bath water -100-105°F water.

Ensure the water does not cool below 100°F – add warm water

Continuously stir the water.

Continue until part is soft and color/sensation return

Active Rewarming of FrozenParts

Dress area with dry, sterile dressings. If hand or foot, place dry sterile dressing between fingers or toes.

Protect against refreezing the warmed part

Expect the patient to complain of severe pain

If patient is alert, give warm fluids slowly. No stimulants or alcohol.

Transport with limb slightly elevated.

Active Rewarming of Frozen Parts

Immerse affectedImmerse affectedpart in warm-part in warm-water bath.water bath.

Exposure to HeatExposure to Heat

If heat gain If heat gain exceeds heat loss, exceeds heat loss, hyperthermia hyperthermia (high body (high body temperature) temperature) occurs.occurs.

Heat Exposure


Climate

High ambient temperature reduces the body’s ability to lose heat by radiation

High relative humidity reduces the body’s ability to lose heat through evaporation

Exercise and activity – can lose more than 1 liter of sweat per hour; loss of electrolytes (sodium, chloride and fluid through sweat)

Age – Elderly

Poor thermoregulation

Medications

Lack of mobility - limited ability to escape heat

Heat Exposure


Heat Exposure


Age – Newborns/Infants

Poor thermoregulation

Can’t remove own clothing

Preexisting Illness

Heart disease

Dehydration

Obesity

Infections/fever

Fatigue

Diabetes

Drugs/medications

Heat Exposure

PredisposingFactors

Signs & Symptoms of HeatCramps or Heat Exhaustion

Muscle cramps (heat cramps – due to continuation of sweating, which causes salt loss and brings on these painful muscle cramps)

Weakness or exhaustion

Dizziness, faintness

Weak, rapid pulse

Continued…

Altered mental status (may be unresponsive)

Skin

Moist (heavy sweating) pale, temperature normal to cool temperature; Heat exhaustion – form of shock brought about by electrolyte, fluid and salt loss – the patient is still sweating

Hot, Dry or moist – dire emergency; Heat Stroke – when a person’s temperature regulating mechanisms fail and the body cannot rid itself of excess heat

Signs & Symptoms of Heat Cramps or Heat Exhaustion

Emergency Care of Heat Exposure Patient with Moist, Pale and Normal to Cool Skin

After performing initial assessment, remove from hot environment and place in cool environment.

Administer high-concentration oxygen.

Loosen or remove clothing.

Cool by fanning.

Put in supine position; elevate legs.

Patient unresponsive/vomiting:

Transport patient to hospital on left side

Patient responsive/not nauseated: Transport/give small amounts of water.

Emergency Care of Heat Exposure Patient with Moist, Pale and Normal to Cool Skin

Signs & Symptoms of Heat Stroke (Hot, Dry or Moist Skin)

Little or no perspiration

Weakness

Loss of consciousness

Rapid pulse

Possible seizures

After performing initial assessment, remove from hot environment and place in cool environment.

Remove clothing.

Administer high-concentration oxygen.

Continued…

Emergency Care of Heat Exposure Patient with Hot, Dry or Moist Skin

Apply cool packs to neck, groin, armpits.

Keep skin wet by applying water by sponge or wet towels.

Fan aggressively.

Transport immediately.

Emergency Care of Heat Exposure Patient with Hot, Dry or Moist Skin

WaterWaterEmergenciesEmergencies

Drowning

Key Term

Death associated with immersion in water

Near-Drowning

Primary concerns:

Everyone’s safety – Do not attempt a rescue in which you must enter deep water or swim, unless you have been trained to do so and are a good swimmer (Reach -> Throw -> Row -> Tow -> Go).

Suspect spine injury if diving accident is involved or unknown.

Near-Drowning

Consider length of time in cold water drowning. Any pulseless, non-breathing patient who has been submerged in cold water should be resuscitated. Biological death can be delayed up to 30 minutes if water is below 70 degrees Fahrenheit. The colder the water, the better the chances for survival.

Near-DrowningComplications of near-drowning:

Airway obstruction

Hypothermia

Cardiac Arrest

Signs of Heart Attack

Injuries to head and neck

Internal injuries

Substance Abuse

Drowning/Near Drowning

Emergency Care of Near-DrowningIn-line immobilization and removal from water with backboard if spine injury is suspected and patient is responsive head manually.

If there is no suspected spine injury, place patient on left side to allow water, vomitus and secretions to drain from upper airway.

Administer oxygen if not already done during the initial assessment.

If gastric distention interferes with artificial ventilation, the patient should be placed on his left side. With suction immediately available, you should place your hand over the epigastric area of the abdomen and apply firm pressure to relieve the distention. This procedure should only be done if the gastric distention interferes with the ability of the EMT to artificially ventilate the patient effectively.

For warm water drowning requiring resuscitation, perform airway obstruction and CPR skills as previously learned.

Patient found face down Patient found face down in in shallow water.shallow water.

Extend patient’s arms straight up.Extend patient’s arms straight up.

Rotate the torso toward you as you lowerRotate the torso toward you as you loweryourself into the water.yourself into the water.

Maintain stabilization by holding theMaintain stabilization by holding thepatient’s head between his arms.patient’s head between his arms.

Positioning of Near-Drowning

Scuba DivingAir Embolism – arterial gas embolism – result of gasses leaving a damaged lung and entering the bloodstream

Blurred vision

Chest pains

Numbness/Tingling sensations in the extremities

Generalized or specific weakness; possible paralysis

Frothy blood in mouth or nose

Convulsions

Rapid lapse into unconsciousness

Respiratory/Cardiac Arrest

Scuba DivingDecompression Sickness – nitrogen gas is trapped in the body tissues and then in the bloodstream due to rapid ascent

Personality changes

Fatigue

Deep pain in muscle/joints

Itchy blotches/mottling of skin

Choking

Coughing

Labored Breathing

Behavior similar to intoxication

Chest pains

Collapse leading to unconsciousness

Skin rashes that keep changing in appearance

Ice Rescues

Protect yourself

Devices to be used to assist in rescue:

Flotation device can be thrown

Rope with a loop on the end

Small, flat-bottomed aluminum boat (this is your best choice)

Ladder

Patient might not help much in process due to hypothermia.

Water Accidents

Any kind of injury or medical condition can be found in the water, so always perform a thorough patient assessment.

Bites andBites andStingsStings

Signs & Symptoms of Bitesand Stings

History of spider/snake bite; insect, scorpion, marine animal sting

Spiders

Brown Recluse/Fiddleback – bites are painless and seldom can one recall being bitten

Black Widow – cause a more immediate reaction

Brown Recluse Spider

Black Widow Spider


Snakes

Dry Bites – when a snake bites a person, but does not inject venom

Pit Vipers – rattlesnakes, copperhead, water moccasins) – 25% of these are dry bites

Coral Snakes – 50% of these are dry bites

Snakes

Rattlesnake Copperhead

Water

Moccasin

Coral Snake

http://stevecreek.com/wp-content/uploads/2008/03/water_moccasin.jpg


Marine Animals

Jelly fish, sea nettle, Portuguese Man-of-War, Coral, Sea Anemone, and Hydra

Sting produces pain with few complication in most cases. Rubbing the affected area with vinegar or rubbing alcohol will reduce the pain.

Marine Animals

Jellyfish Sea Nettle Portuguese

Man-of-War

Sea Anemone Hydra

Coral

http://animals.nationalgeographic.com/animals/enlarge/portuguese-man-o-war_image.html


Pain

Redness

Swelling

Weakness or numbness

Blotchy skin

Continued…

Dizziness

Chills

Fever

Nausea

Vomiting

Bite marks or stinger

Respiratory Distress


Stinger present

Scrape with blunt edge to remove (i.e. edge of credit card).

Avoid tweezers or forceps (may squeeze venom from the venom sac into the wound).

Continued…

Treatment of Bites and Stings

Wash area gently.

Remove jewelry distal to affected area before swelling begins.

Position injection site slightly below heart.

Do not apply cold to snake bites. Do not cut or suction the snake bite.

Consult medical control regarding a constriction band for a snake bite.

Observe for allergic reaction.

Continued…


Treat for shock.

Immobilize affected limb.

Prevent exertion of patient.

Follow any local protocols.

Continued…


Snakebites and Constricting Bands

If using a constricting band, it should be a ¾ to 1 ½ inches wide and made of soft rubber.

The band will restrict the flow of lymph, not of blood.

The bands should be placed approximately 2 inches above and below the site of the wound, bun not on both sides of a joint.

If only one constricting band is available, it should be placed above the wound


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CHAPTER 22 Environmental Emergencies. Temperature Regulation