Transcript SECTION 2 - Sam Scheller

Chapter 15
Environmental
Emergencies
Chapter 15: Environmental Emergencies
Objectives (1 of 4)
• List the signs and symptoms of exposure to
cold.
• Explain the steps in providing emergency
medical care to a patient exposed to cold.
• List the signs and symptoms of high altitude
illnesses.
• Explain the steps in providing emergency
care to a patient with high altitude illness.
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Chapter 15: Environmental Emergencies
Objectives (2 of 4)
• Explain the steps in providing emergency
care for an avalanche victim.
• List the signs and symptoms of exposure
to heat.
• Explain the steps in providing emergency
care to a patient exposed to heat.
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Chapter 15: Environmental Emergencies
Objectives (3 of 4)
• Explain the steps in providing emergency
care for a patient who has been struck by
lightning or received an electrical injury.
• Recognize the signs and symptoms of waterrelated emergencies.
• Demonstrate the assessment and emergency
care of a patient with exposure to cold.
• Demonstrate the assessment and emergency
care of a patient with high altitude illnesses.
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Chapter 15: Environmental Emergencies
Objectives (4 of 4)
• Demonstrate the assessment and emergency
care of an avalanche victim.
• Demonstrate the assessment and emergency
care of a patient with exposure to heat.
• Demonstrate the assessment and emergency
care of a patient affected by lightning or electrical
exposure.
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Chapter 15: Environmental Emergencies
Cold Exposure
• Normal body temperature exists
within a narrow range
• Cold may cause injury to parts of
the body
• Cold may cause injury to the
body as a whole
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Chapter 15: Environmental Emergencies
Loss of Body Heat (1 of 2)
• Conduction
– Transfer of heat from
body to colder object
• Convection
– Transfer of heat
through circulating air
• Evaporation
– Cooling of body
through sweating
• Radiation
– Loss of body
heat directly
into a colder
environment
• Respirations
– Loss of body
heat during
breathing
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Chapter 15: Environmental Emergencies
Loss of Body Heat (2 of 2)
• Rate and amount of heat loss
can be modified in three ways:
– Increase heat production
(shivering).
– Move to sheltered area where
heat loss is decreased.
– Wear insulated clothing.
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Chapter 15: Environmental Emergencies
Hypothermia
• Lowering of the body temperature below 95°F
(35ºC)
• Weather does not have to be below freezing
for hypothermia to occur.
• As the body cools, functions slow.
• A cooler body loses the ability to regulate
temperature and to generate heat.
• The patient is unaware of the change and the
condition is insidious.
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Chapter 15: Environmental Emergencies
Hypothermia Risks
• Elderly persons and infants are at
higher risk.
• People with other illnesses and injuries
are susceptible to hypothermia.
• High altitude can increase the risk.
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Chapter 15: Environmental Emergencies
Hypothermia and Death
• 50% of severe cases are lethal.
• Patients may appear dead, but:
– “No one is dead until warm and
dead!”
– Death is usually the result of
ventricular fibrillation (V-fib).
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Chapter 15: Environmental Emergencies
Hypothermia Categories
• Grouped into three categories:
– Acute (less than an hour)
– Subacute (1 to 24 hours)
– Chronic (a day or more)
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Chapter 15: Environmental Emergencies
Mild Hypothermia
• Rectal temperature above 90°F (32°C)
• Shivering can provide needed heat.
• Treat dehydration with warm,
sweetened liquids.
• Avoid alcohol and caffeine.
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Chapter 15: Environmental Emergencies
Severe Hypothermia
• Rectal temperature below 90°F (32°C)
• Out-of-hospital mortality is high due to
V-fib, metabolic, or electrolyte
complication.
• Best results occur with detection,
stabilization of core temperature, gentle
handling, and transport.
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Chapter 15: Environmental Emergencies
Severe Hypothermia
Treatment (1 of 2)
• Spend several minutes evaluating
vital signs.
• Avoid aggressive rewarming.
• CPR can precipitate V-fib.
• If CPR is started, it must continue
until hospitalization.
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Chapter 15: Environmental Emergencies
Severe Hypothermia
Treatment (2 of 2)
• Carefully evaluate the method of
evacuation. Avoid rough handling.
• In a wilderness setting, use a slow
rewarming method, usually body-tobody contact.
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Chapter 15: Environmental Emergencies
Hypothermia Settings
• Immersion—contact with cold water
• Field—contact with cold weather
• Urban—individuals predisposed to poor
or inadequate thermoregulation
• Submersion—drowning and near
drowning
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Chapter 15: Environmental Emergencies
Assessment of
Hypothermic Patients (1 of 2)
• It is always preferable to anticipate and
prevent.
• Mental status and physical actions can help
estimate core temperature.
– Shivering and appropriate actions,
temperature > 90°F (32°C)
– Uncoordinated actions and no shivering,
temperature < 90°F (32°C)
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Chapter 15: Environmental Emergencies
Assessment of
Hypothermic Patients (2 of 2)
• Scene size-up
– Include consideration of setting and
predisposing conditions.
• Initial assessment:
– Prevent further heat loss.
– Take your time assessing vital signs.
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Chapter 15: Environmental Emergencies
Emergency Medical Care
• Stabilize body temperature and prevent
further heat loss.
• Rewarm the patient appropriately.
• Rewarm the core first if possible.
• Treat gently.
• If conscious, give warm sweet fluids to
treat dehydration.
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Chapter 15: Environmental Emergencies
Rewarming Methods: Fast
• Usually water based
– Baths
– Heated blankets
– Peritoneal dialysis
– Heart-lung machine
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Chapter 15: Environmental Emergencies
Rewarming Methods: Slow
•
•
•
•
•
•
Shivering
Body-to-body contact
Hot water bottles or warm rocks
Chemical heating pads
O2 heater
Stoves or fires
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Chapter 15: Environmental Emergencies
Local Cold Injuries (1 of 3)
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Chapter 15: Environmental Emergencies
Local Cold Injuries (2 of 3)
• Frostnip
– Cold-induced superficial blood
vessel constriction
• Immersion (trench) foot
– Prolonged exposure to cold water
• Frost bite
– Freezing of a body part, usually
an extremity
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Chapter 15: Environmental Emergencies
Local Cold Injuries (3 of 3)
• Investigate any predisposing factors.
• The development of frostbite is
progressive.
• It is difficult to predict the severity of
injury and the patient’s outcome.
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Chapter 15: Environmental Emergencies
Frostbite
• The actual freezing of a body part
• The amount of damage depends
on the extent and duration of
freezing.
• The part will have a wooden or
waxy appearance.
• Blisters often form with thawing.
• Gangrene is a complication in
severe cases.
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Chapter 15: Environmental Emergencies
Assessment and Emergency
Care of Frostbite
• Based on direct inspection and palpation
• For frostnip, provide direct body heat and
seek shelter.
• Consider the possibility of hypothermia.
• Rewarm the part rapidly in a water bath.
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Chapter 15: Environmental Emergencies
Water Bath
• Water temperature should be between 102oF to
108oF.
• Recheck water temperature and stir to circulate.
• Remove constricting bands: rings, watches, etc.
• Keep body part in water for 20 to 30 minutes.
• Watch for tissue color change.
• Give warm drinks and advise of impending pain.
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Chapter 15: Environmental Emergencies
Wilderness and Frostbite
• Refreezing will lead to gangrene.
• Wrap in bulky dressings and leave
blisters intact if possible.
• Patients can be evacuated after
thawing, but guard against refreezing.
• Prevention is the best treatment!
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Chapter 15: Environmental Emergencies
Cold Exposure and You
• Rescuers are at risk for hypothermia
when working in a cold environment.
• Stay aware of local weather conditions.
• Dress appropriately and be prepared.
• Never allow yourself to become a
casualty!
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Chapter 15: Environmental Emergencies
High Altitude Illness (1 of 5)
• With ascent, the following changes
occur:
– Solar radiation increases.
– Temperature and humidity fall.
– PO2 and atmospheric pressure
decrease.
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Chapter 15: Environmental Emergencies
High Altitude Illness (2 of 5)
• For every 1000’ (309 m) of altitude gain:
– Dry temperatures drop 3.5°F (1.6°C).
– The barometer drops 20 mm Hg.
– Ultraviolet radiation increases 5%.
– Oxygen concentration remains constant
at 21%, but the PO2 drops.
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Chapter 15: Environmental Emergencies
High Altitude Illness (3 of 5)
• Rapid ascent produces acute and
chronic effects.
• Acute effects are due to hypoxia.
• Chronic effects lead to circulatory,
respiratory, and nervous system
changes.
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Chapter 15: Environmental Emergencies
High Altitude Illness (4 of 5)
• Factors that influence the effects of altitude
include:
– Speed of ascent
– Final altitude attained
– Duration of exposure
– Exertion
– Type of travel: foot, car, airplane
– The altitude at which one sleeps
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Chapter 15: Environmental Emergencies
High Altitude Illness (5 of 5)
• Types of illnesses:
– Acute mountain sickness (AMS)
– High altitude cerebral edema (HACE)
– High altitude pulmonary edema (HAPE)
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Chapter 15: Environmental Emergencies
Acute Mountain Sickness (1 of 3)
• The most common high-altitude illness
• Reported in 20% of all snowsports guests at
Rocky Mountain resorts
• Documented in Yellowstone National Park
• Caused by:
– Failure to increase respirations
– Fluid retention
– Increased cerebral blood flow and
inflammation
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Chapter 15: Environmental Emergencies
Acute Mountain Sickness (2 of 3)
• Signs and symptoms include:
– Headache, worse at night or when bending
over
– Apathy
– Insomnia
– Lightheadedness
– Loss of appetite, nausea, and vomiting
– Other generalized symptoms of malaise
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Chapter 15: Environmental Emergencies
Acute Mountain Sickness (3 of 3)
• Predisposing factors include:
–
–
–
–
Speed of ascent
Overexertion
Cold weather
Youthfulness in adults
• Fitness does not seem to promote immunity.
• A brisk respiratory response seems to lessen
susceptibility.
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Chapter 15: Environmental Emergencies
High Altitude Cerebral Edema
• Signs and symptoms include:
– Similar to AMS, but more intense
– Ataxia, the inability to balance or walk
– Altered mental status progressing to
unresponsiveness
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Chapter 15: Environmental Emergencies
High Altitude
Pulmonary Edema (1 of 3)
• 10X more frequent than HACE
• Researched extensively in the Himalayas,
Canada, and Alaska
• Hypoxia-induced changes lead to:
–
–
–
–
Increased pulmonary arterial pressure
Capillary wall damage
Opening of high pressure shunts
Increased fluid in alveoli
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Chapter 15: Environmental Emergencies
High Altitude
Pulmonary Edema (2 of 3)
• Early signs and symptoms include:
– Dry, nighttime cough
– Increasing dyspnea
– Mild chest pain
– A decrease in the ability to exercise
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Chapter 15: Environmental Emergencies
High Altitude
Pulmonary Edema (3 of 3)
• Late signs and symptoms include:
– Cyanosis
– Cough that produces pink frothy sputum
– Tachycardia and tachypnea at rest
– Loud, wet rales
– Severe dyspnea
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Chapter 15: Environmental Emergencies
Assessment of
High Altitude Illness
• Scene size-up, consider setting
• Initial assessment, especially respiratory
rate and rhythm
• Complete SAMPLE history
• Assess lung sounds, the ability to walk,
and balance.
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Chapter 15: Environmental Emergencies
Emergency Care of
High Altitude Illness (1 of 2)
• Skiing, trekking, and climbing parties:
–
–
–
–
Rapid descent for HACE and HAPE patients
Preferably 2,000’ (610 m)
O2 (1 to 2 L/min), if available
Rest, without further ascent, may resolve mild
AMS.
– Aspirin or ibuprofen for headache (HA)
– Gamow bag
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Chapter 15: Environmental Emergencies
Emergency Care of
High Altitude Illness (2 of 2)
• High altitude resorts
–
–
–
–
Rapid access to medical treatment
High-flow oxygen
May require immediate descent
Rest, mild diet, and abstinence may resolve
mild AMS.
– Prescriptions can help acutely and
prophylactically
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Chapter 15: Environmental Emergencies
Sunburn, Windburn, and
Snowblindness
• Altitude, snow, and bodies of water increase
risk.
• Clouds do not offer protection.
• Sunburn is a 1° or 2° burn cause by
ultraviolet light:
– UVA at 290 – 320 nanometers
– UVB at 320 – 400 nanometers
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Chapter 15: Environmental Emergencies
Sunburn
• Repeated exposures can lead to:
– Wrinkling, darkening, and thickening
of skin
– Benign and malignant cancers
 Actinic keratoses, basal and
squamous cell carcinomas
 Malignant melanoma
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Chapter 15: Environmental Emergencies
Types of Sunscreen
• Physical
– Blocks the sunlight mechanically
– Zinc oxide, titanium dioxide, red
petrolatum
• Chemical
– Chemicals filter rays
– UVA- Parsol, anthranilates, oxybensone
– UVB- salicylates, cinnamates, PABA,
Padimate
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Chapter 15: Environmental Emergencies
Sunscreen
• Sun protection factor (SPF), 2 to 50
– Number refers to how much longer a person
can be safely exposed.
– SPF 15 is the practical minimum; SPF 30 is the
practical maximum.
• Apply early and often. Thicker preparations can
prevent windburn as well.
• Treat burn patients with cool compresses and
later with lotion and aloe.
• Extensive/blistered burns need physician care.
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Chapter 15: Environmental Emergencies
Snowblindness
• A burn of the conjunctiva caused by UV
radiation
• Can be prevented by wearing
sunglasses or goggles
• Symptoms develop 6 to 12 hours after
exposure.
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Chapter 15: Environmental Emergencies
Snowblindness:
Signs and Symptoms
•
•
•
•
•
“Sand in the eye” irritation
Pain with eye motion
Tearing
Light sensitivity
Swelling around the eye
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Chapter 15: Environmental Emergencies
Snowblindness Treatment
•
•
•
•
•
Remove to darker surroundings
Cover both eyes
Apply cool compresses.
Nonprescription pain relievers
Prescription medications in severe
cases
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Chapter 15: Environmental Emergencies
Body Temperature
• Normal body temperature is 98.6ºF.
• Body attempts to maintain normal
temperature despite ambient temperature.
• Body cools itself by sweating (evaporation)
and dilation of blood vessels.
• High temperature and humidity decrease
effectiveness of cooling mechanisms.
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Chapter 15: Environmental Emergencies
Hyperthermia (1 of 2)
• Core temperature > 101°F (38°F)
• Cooling mechanisms become overwhelmed
and the body is unable to cope.
• Illnesses can develop when:
– Air temp is high
– Humidity is high
– Dehydration curtails the ability to sweat
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Chapter 15: Environmental Emergencies
Hyperthermia (2 of 2)
• Predisposing risk factors include:
–
–
–
–
–
Extremes of age
Poor thermoregulation
Heart disease, COPD, diabetes, and obesity
Limited mobility
Drug and alcohol abuse
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Chapter 15: Environmental Emergencies
Heat Cramps
• Painful muscle spasms
• Remove the patient from hot
environment.
• Rest the cramping muscle.
• Replace fluids by mouth.
• If cramps persist, arrange for
transport to hospital.
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Chapter 15: Environmental Emergencies
Heat Exhaustion
• Onset while working hard or exercising in hot
environment
• In elderly and young, onset may occur while
at rest in hot, humid, and poorly ventilated
areas.
• Signs and symptoms:
– Cold, clammy skin
– Dry tongue and thirst
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Chapter 15: Environmental Emergencies
Heat Exhaustion:
Signs and Symptoms
• Normal vital signs, but pulse can
increase and blood pressure can
decrease.
• Dizziness, weakness, or fainting
• Normal or slightly elevated body
temperature
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Chapter 15: Environmental Emergencies
Emergency Care for
Heat Exhaustion
• Remove extra clothing, remove
patient from hot environment.
• Give patient oxygen.
• Have patient lie down and
elevate legs.
• If patient is alert, give water or
diluted electrolyte solution slowly.
• Be prepared to transport.
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Chapter 15: Environmental Emergencies
Heatstroke
• Signs and symptoms:
– Hot, dry, flushed skin
– Change in behavior leading to
unresponsiveness
– Pulse rate is rapid, then slows.
– Blood pressure drops.
– Death can occur if the patient is not treated.
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Chapter 15: Environmental Emergencies
Emergency Care for
Heatstroke (1 of 2)
• Move patient out of the hot
environment.
• Remove the patient’s clothing.
• Administer oxygen.
• Apply cold packs to the
patient’s neck, armpits, and
groin.
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Chapter 15: Environmental Emergencies
Emergency Care for
Heatstroke (2 of 2)
• Cover the patient with wet towels or
sheets.
• Aggressively fan the patient.
• Immediately transport patient.
• Notify hospital of patient’s condition.
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Chapter 15: Environmental Emergencies
Lightning and Electrical Injury
•
•
•
•
•
Significant hazard
1,000 deaths annually
100 to 200 due to lightning
Power transmission lines are widespread.
Outdoor activities in the spring and summer
increase the risk of lightning strike.
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Chapter 15: Environmental Emergencies
Electrical Injury (1 of 2)
• Insult to respiratory centers that lead to
respiratory arrest
• Cardiac arrest
– AC current = V-fib
– DC current = asystole
• Severe burns to skin, muscle, bone, and
organs
– Can produce large and devastating burns
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Chapter 15: Environmental Emergencies
Electrical Injury (2 of 2)
• Direct injury to nerves that lead to pain,
paralysis, blindness, deafness, and loss
of speech
• Kidney overload and injury due to toxic
concentrations of waste
• Falls due to loss of balance or muscle
contractions
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Chapter 15: Environmental Emergencies
Lightning Injury
• Lightning is usually associated with
cumulonimbus clouds (thunderheads).
• Can occur during snowstorm
• 30% fatality rate with strikes
• Victims may display a characteristic burn
pattern that is fern shaped.
• Can be direct strike or by conducted current
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Chapter 15: Environmental Emergencies
Emergency Care for
Electrical Injury (1 of 3)
• Rescue may require special training and
equipment; protect yourself.
• Remove the victim from the electrical
source.
• Those trapped in vehicles will need to
jump clear to avoid being grounded.
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Chapter 15: Environmental Emergencies
Emergency Care for
Electrical Injury (2 of 3)
• Don’t touch victims until live wires are
clear.
• Start CPR immediately in the case of
cardiac arrest.
• During triage, these patient (electrical
injury) should be cared for first.
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Chapter 15: Environmental Emergencies
Emergency Care for
Electrical Injury (3 of 3)
• Be prepared for: burns, fractures, multiple
trauma, neck, and spinal injuries.
• Provide high-flow oxygen.
• Pulses may return, but patients may require
lengthy respiratory support.
• Provide assessment, stabilization, and
evacuation consistent with trauma care.
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Chapter 15: Environmental Emergencies
Prevention of Electrical Injury
(1 of 2)
• Conductors transmit electricity and
insulators resist electrical flow.
• Electricity follows the path of least
resistance.
• Urban injuries usually involve
appliances or accidental contact with
power lines.
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Chapter 15: Environmental Emergencies
Prevention of Electrical Injury
(2 of 2)
• Avoid areas prone to lightning strike:
– Bodies of water
– Ridges, high points, and lone trees
– Telephones and appliances
– Small caves or wide open spaces
– Large metal structures
• Count seconds between lightning and thunder
and divide by 5; the result is distance in miles.
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Chapter 15: Environmental Emergencies
Drowning and Near Drowning
• Drowning
– Death as a result of suffocation after
submersion in water
• Near drowning
– Survival, at least temporarily, after
suffocation in water
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Chapter 15: Environmental Emergencies
Drowning Process (1 of 2)
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Chapter 15: Environmental Emergencies
Drowning Process (2 of 2)
• Small amounts of water can cause
laryngospasm.
• This may inhibit rescue breathing.
• Hypoxia leads to unresponsiveness.
• 85% to 90% involve significant amount
of water in the victim’s lungs.
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Chapter 15: Environmental Emergencies
Emergency Medical Care
• Begin rescue breathing as soon as
possible.
• Maintain cervical spine stabilization.
• If air does not enter the patient’s lungs,
treat for obstructed airway.
• Check pulse and start CPR if needed.
• Keep patient warm and transport.
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Chapter 15: Environmental Emergencies
Spinal Injuries in
Submersion Incidents
• Suspect spinal injury if:
– Submersion has resulted from a diving
mishap or long fall.
– Patient is unresponsive.
– Patient complains of weakness,
paralysis, or numbness.
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Chapter 15: Environmental Emergencies
Water Rescuer Safety
•
•
•
•
•
Protect yourself!
“Reach, throw, row, and only than go”
Wear a personal flotation device (pfd).
Guard against hypothermia.
When working on or near water,
develop a pre-arranged rescue plan.
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Chapter 15: Environmental Emergencies
Spinal Stabilization in Water
• Turn the patient supine.
• Restore the airway and begin
ventilations.
• Secure a backboard under the
patient.
• Remove the patient from the
water.
• Cover the patient with a blanket.
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Chapter 15: Environmental Emergencies
Resuscitation Efforts
• Hypothermia can protect vital organs
from hypoxia.
• Documented case of a survivor of a 66minute cold water submersion
• Diving reflex may cause heart rate to
slow.
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Chapter 15: Environmental Emergencies
Avalanche Injuries (1 of 2)
• Fatalities:
– 80% - asphyxia
– 10% to 15% - trauma
– 5% - hypothermia
• 92% survival rate if uncovered within
15 minutes
• By 35 minutes, only 30% survive.
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Chapter 15: Environmental Emergencies
Avalanche Injuries (2 of 2)
• Best chance of survival is by companion
rescue.
• Most victims are backcountry skiers,
snowboarders, climbers, and snowmobile
riders.
• Backcountry users should be trained and carry:
– Shovel
– Avalanche probe
– Avalanche transceiver
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Chapter 15: Environmental Emergencies
Emergency Care for
Avalanche Victims
• Uncover head and chest quickly
and carefully.
• Treat for hypothermia.
• Provide high-flow oxygen.
• Assess and treat for trauma.
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Chapter 15: Environmental Emergencies
Ice Rescue
• Is very hazardous
• Cold water can incapacitate victims
quickly.
• Use personal flotation devices (pfd).
• Use ladders or objects to distribute weight.
• Self-rescue with sharp tipped objects or by
rolling
• Remove skis or snowboard.
• Assess and treat hypothermia.
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Chapter 15: Environmental Emergencies
Diving Problems
• Descent problems
– Usually due to the sudden increase in
pressure on the body as the person dives
• Bottom problems
– Not commonly seen
• Ascent problems
– Air embolism and decompression sickness
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Chapter 15: Environmental Emergencies
Signs and Symptoms of
Air Embolism (1 of 2)
• Blotchy skin
• Froth at the mouth and nose
• Severe pain in muscle, joints,
or abdomen
• Dyspnea and/or chest pain
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Chapter 15: Environmental Emergencies
Signs and Symptoms of
Air Embolism (2 of 2)
• Dizziness, nausea, and vomiting
• Dysphasia
• Difficulty with vision
• Paralysis and/or coma
• Irregular pulse or cardiac arrest
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Chapter 15: Environmental Emergencies
Decompression Sickness
(The Bends)
• Occurs when bubbles of gas obstruct blood
vessels
• Can result from rapid ascent
• Most common symptom is abdominal and/or
joint pain.
• Symptoms may develop after several hours.
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Chapter 15: Environmental Emergencies
Caring for Air Embolism and
Decompression Sickness
•
•
•
•
Remove the patient from the water.
Keep patient calm.
Begin BLS and administer oxygen.
Place the patient in the left lateral recumbent
position with his or her head down.
• Provide prompt transport to hyperbaric
chamber.
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Chapter 15: Environmental Emergencies
Other Water Hazards
• Hypothermia from water
immersion.
• Breath-holding syncope
• Swimmer’s ear
• Injuries from recreational
equipment or marine animals
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