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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.
2
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.
3
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.
4
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.
5
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
6
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
7
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.
8
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.
10
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).
11
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.
13
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.
15
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.
16
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
17
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)
18
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.
19
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
22
Chapter 15: Environmental Emergencies
Local Cold Injuries (1 of 3)
23
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
24
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.
25
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.
26
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.
27
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!
29
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!
30
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.
31
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.
32
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.
33
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
34
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
36
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
37
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.
38
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
39
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
40
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
41
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
42
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.
43
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
44
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
45
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
46
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
47
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
48
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.
49
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.
50
Chapter 15: Environmental Emergencies
Snowblindness:
Signs and Symptoms
•
•
•
•
•
“Sand in the eye” irritation
Pain with eye motion
Tearing
Light sensitivity
Swelling around the eye
51
Chapter 15: Environmental Emergencies
Snowblindness Treatment
•
•
•
•
•
Remove to darker surroundings
Cover both eyes
Apply cool compresses.
Nonprescription pain relievers
Prescription medications in severe
cases
52
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.
53
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
54
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
55
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.
56
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
57
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
58
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.
59
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.
60
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.
61
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.
62
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.
63
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
64
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
65
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
66
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.
67
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.
68
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.
69
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.
70
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.
71
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
72
Chapter 15: Environmental Emergencies
Drowning Process (1 of 2)
73
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.
74
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.
75
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.
76
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.
77
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.
78
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.
79
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.
80
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
81
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.
82
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.
83
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
84
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
85
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
86
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.
87
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.
88
Chapter 15: Environmental Emergencies
Other Water Hazards
• Hypothermia from water
immersion.
• Breath-holding syncope
• Swimmer’s ear
• Injuries from recreational
equipment or marine animals
89