Transcript Cold-related Injuries and Illnesses Hypothermia, Frostbite, and Other Health Problems

Cold-related Injuries and
Illnesses
Hypothermia, Frostbite, and
Other Health Problems
What this presentation covers
• Summary of factors increasing risk of cold-related
injuries and illnesses
• Summary of preventive measures against coldrelated injuries and illnesses
• Causes, signs and symptoms, and treatment of
– Hypothermia
– Chilblains
– Frostbite
– Immersion Foot
(Trench foot)
– Frostnip
See “Working in Cold Environments” for more information on the
causes and risk factors of cold-related illnesses and injuries, and
preventive measures to minimize the hazards from cold exposure.
Factors Increasing Risk of Cold Injuries/Illnesses
• Previous cold-related injury
• Nicotine (Smoking)
• Predisposing health
conditions
• Age
• Fatigue, poor physical
condition
• Poor nutrition
• Dehydration
• Medication
• Alcohol
• Caffeine
• Improper clothing and
equipment
• Under-activity
• Over-activity
• Cold conditions:
–Temperature
–Wind
–Wetness
• Length of exposure
Preventing Cold-related Injuries and Illnesses
• Wear appropriate clothing.
• Avoid wetness or excessive sweating.
• Stay dry. Change into dry clothes and shoes if they
become wet.
• Keep active. Avoid sitting or standing still for prolonged
periods.
• Take frequent breaks in warm, shielded areas.
• Work in pairs to keep an eye on each other.
• Consume warm, high calorie food often.
• Drink plenty of warm non-caffeinated, non-alcoholic liquids.
• Don’t smoke.
Hypothermia
Hypothermia ("low heat”) is a
potentially serious and fatal
health condition resulting from
the body’s failure to maintain
its normal core temperature
of 98.6°F.
When exposed to cold conditions,
your body begins to lose heat
faster than it can be produced.
Prolonged exposure to cold
eventually uses up your body’s
stored energy and your core
body temperature drops to
95°F or below. The result is
hypothermia.
Hypothermia is a
medical emergency!
Hypothermia
Body temperature that is too low affects the brain, making
the affected person unable to think clearly or move well.
This makes hypothermia
particularly dangerous
because a person may not
realize it is happening and
may deny being in any
trouble.
Recognition of symptoms
depends on co-workers'
ability to identify symptoms
and to seek medical help.
Hypothermia
Most cases of hypothermia occur in air temperatures from
30°F to 40°F.
However, it can occur at warmer
temperatures as high as 65°F, or
more, if a person becomes chilled
from prolonged exposures to
wetness (rain, snow, submersion
in cold water, or sweat) and
accompanying winds.
Generally, in cold dry environments, hypothermia occurs over
a period of hours. In cold water,
core temperature can drop to
dangerous levels in a matter of
minutes.
Immersion Hypothermia
Water transfers heat away from the human body 25 times
faster than air, so even moderate water temperatures can
be dangerous in a relatively short time.
Water Temperature in
Degrees F (Degrees C)
Exhaustion or
Unconsciousness
Expected Time of
Survival
32.5 (0.3)
Under 15 min.
Under 15 to 45 min.
32.5 to 40 (0.3 to 4.5)
15 to 30 min.
30 to 90 min.
40 to 50 (4.5 to 10)
30 to 60 min.
to 3 hrs.
50 to 60 (10 to 15.5)
to 2 hrs.
to 6 hrs.
60 to 70 (15.5 to 21)
2 to 7 hrs.
2 to 40 hrs.
70 to 80 (2 to 26.5)
2 to 12 hrs.
3 hrs. to indefinite
Over 80 (Over 26.5)
Indefinite
Indefinite
Stages of Hypothermia
Hypothermia progresses through three indistinct but
sequential stages as core body temperature continues
to decline:
Approximate
Core Body Temperature
Mild hypothermia
98°F - 95°F
Moderate hypothermia
95°F - 90°F
Severe hypothermia
<90°F
Mild Hypothermia
Signs/Symptoms
Physical
• shivering, mild to severe
Mental
• irritability
• sensation of cold, then
pain in extremities
• pale, waxy, cold skin
• numbness of hands
• unable to perform complex
tasks (fumbling with items
in the hand)
• able to walk and talk
If shivering can be stopped voluntarily  mild hypothermia
Moderate Hypothermia
Signs/Symptoms
Physical
Mental
• intense shivering becomes
persistent and violent
• confused, may appear alert
• sluggish; labored movements
• stumbling
• loss of fine motor coordination
in hands (fumbling)
Watch for the “-umbles”
• stumbles
• mumbles
• fumbles
• grumbles
• irrational behavior –
“Paradoxical Undressing”
(person starts to undress,
unaware s/he is cold)
• apathetic/flattened affect –
"I don't care” attitude"
• withdrawn behavior
• slurred speech, difficulty
speaking
• sluggish thinking
• signs of depression
Severe Hypothermia
Signs/Symptoms
Physical
• shivering stops
• exposed skin blue or puffy
• muscle coordination very
poor, muscle rigidity
• stupor
• can’t walk; falls to ground
and curls up into fetal
position to conserve heat
• decreased pulse and
respiration rate
• irregular heart rhythm
Mental
• incoherent, irrational
behavior
• may be able to maintain
posture and appearance of
awareness
• semi-conscious, drowsy
• loss of awareness of others
• amnesia, memory lapses
Possible Death from Hypothermia
“No one is dead until warm and dead”
Core body temperature below 82°F - 78°F
Physical
Mental
• erratic, shallow breathing
• Brain activity seriously slowed
• may not be able to feel
pulse
• unconscious, appears
comatose or dead
• pupils dilated and fixed
• cold, blue skin
• unresponsive to any stimuli
• pulmonary edema, cardiac
and respiratory failure
• death possible below 78°F
Worker may appear dead
and show all the accepted
clinical signs of death, but
many of these people have
made complete recoveries
when re-warmed.
Treatment of Hypothermia
Treatment depends on the severity of the hypothermia.
Mild Hypothermia
• Remove wet clothes from victim and
replace with dry clothes and/or wrap
in warm blankets; cover the head.
• Move to a warm environment.
• Do not exercise to warm up.
• Do not re-warm person in a warm
bath or by massaging or rubbing.
• Drink a warm (not hot) sugary drink
Avoid drinks with caffeine (coffee,
tea, or hot chocolate) or alcohol.
Handle the victim gently and
minimize his or her exertion.
• Transport victim to an emergency
medical facility for evaluation.
Treatment of Hypothermia
Moderate Hypothermia
• Call for emergency help.
• Follow the procedures on the
preceding slide.
In addition:
• Cover all extremities
completely, place very warm
objects, such as hot packs or
water bottles on the victim's
head, neck, chest and groin.
Arms and legs should be
warmed last.
Handle the victim gently. Rough
handling can cause heartbeat
irregularities and death.
Treatment of Hypothermia
Severe Hypothermia
• Call for emergency help.
• Give CPR if necessary.
• Follow the procedures for treating
mild hypothermia.
• Do not apply external heat (hot water
bath, heat lamp, electric blanket,
electric heater, etc.) to re-warm.
• Transport the victim to an emergency
medical facility as soon as possible.
Handle the victim very gently.
Transport to hospital for
treatment as soon as possible.
Frostbite
In cold conditions, your body
reduces heat loss and increases
heat production in order to
maintain an internal (core)
body temperature of 98.6°F.
Over time, your body will decrease
blood flow to your extremities and
outer skin and shift it to the body
core to keep the internal organs
warm.
However, this allows exposed skin
and the extremities to cool rapidly
and increases the risk of coldrelated injuries, such as frostbite.
Normal
core body
temperature:
98.6°F
Body Core
 Heart
 Brain
 Lungs
• Liver
• Kidneys
Extremities
• Legs,
feet
• Arms,
hands
Frostbite
Frostbite occurs when the deep layers of the skin and other body
tissues freeze (tissue temperature <28°F-30°F). Ice crystals form,
destroying tissues and causing permanent damage. In severe
cases, amputation of the frostbitten area may be required.
Frostbite typically affects the
• toes/feet
• nose
• fingers/
hand
• cheeks
• ears
• chin
These parts are farthest from the body core, receive less
blood flow, and are thinner so they cool faster.
Frostbite
Causes
• Exposure to below freezing
temperatures
• Can occur in above freezing
temperatures due to wind chill
factors and wetness
air temp.
+
cold
wind = condition
+
wetness
• Contact with extremely cold
objects (especially metal)
• Contact with cooled or
compressed gases, at normal
temperatures (e.g., liquid
nitrogen)
Direct skin exposure to freezing
metal, extreme cold, or high winds
can cause frostbite in minutes.
Frostbite
Frostbite can be classified into two main divisions:
• Superficial (mild)
• Deep (severe)
The extent of frostbite depends on the extremeness of
conditions and duration of exposure.
Superficial Frostbite
• initially redness in light skin,
grayish in dark skin
• burning, tingling, itching, or
cold sensations in the affected
areas, followed by numbness
• skin turns white, waxy; some
resistance when pressed (feels
firm or “wooden” but underlying
tissue is soft); cold to the touch
• may have blistering
Photo courtesy of USACHPPM
• includes all layers of the skin
Deep Frostbite
• involves skin, muscle, tendons,
nerves, blood vessels; may
include bone
• white or yellowish waxy skin
that turns purplish blue as it
thaws
• underlying tissue hard, no
resistance when pressed, may
appear blackened and dead
• blood-filled blisters and
swelling may develop
• may develop blood clots
Photos courtesy of USACHPPM
Deep Frostbite
• significant pain as affected areas re-warm; dull continuous ache
becomes throbbing sensation in 2-3 days and may last weeks
to months
• frostbitten skin is highly susceptible to infection, and gangrene
(death and decay of body tissues) may develop
• time will reveal the final amount of tissue damage
• many people with frostbite may also be experiencing
hypothermia
Photos courtesy of USACHPPM
Treatment of Frostbite
• Move the person to a warm dry area. Don’t leave the person
alone.
• Remove any wet or tight clothing that may cut off blood flow to
the affected area.
• Treat for hypothermia if victim is also experiencing
hypothermia. Saving their lives is more important than
preserving a finger or foot. Perform CPR if necessary.
• Do not rub the affected area, because rubbing causes damage
to the skin and tissue.
• Gently place the affected area in a warm (105°F) water bath
and monitor the water temperature to slowly warm the tissue.
Don’t pour warm water directly on the affected area because it
will warm the tissue too fast causing tissue damage. Warming
takes about 25-40 minutes.
Treatment of Frostbite
• After the affected area has been warmed, it may become
puffy and blister. The affected area may have a burning
feeling or numbness. When normal feeling, movement, and
skin color have returned, the affected area should be dried
and wrapped to keep it warm.
NOTE: If there is a chance the affected area may get cold
again, do not warm the skin. If the skin is warmed
and then becomes cold again, it will cause severe tissue
damage.
• Seek medical attention as soon as possible.
Frostnip
Frostnip is the mildest form of a freezing cold injury. Only
the very outer layers of the skin freeze, usually on the
cheeks, earlobes, fingers, and toes, and also nose and chin.
• Usually occurs at about 59°F
• Generally reversible, no tissue injury or permanent
damage
• Skin turns white, top layer of skin feels hard but
deeper tissue still feels normal (soft)
• May feel tingling or numbness
Frostnip
Frostnip can be prevented by wearing warm clothing and
footwear.
Treatment
• Gently rewarm affected area by blowing warm air on it
or placing it against a warm body part (e.g., another
person’s stomach or armpit).
• Do not use very hot objects such as hot water bottles
to rewarm the area or person.
• Do not rub the affected part - ice crystals in the tissue
can cause damage if the skin is rubbed.
Chilblains
Chilblains is caused by prolonged and repeated exposure of bare
skin to air temperatures above freezing (32°F) to 60°F,
accompanied by high humidity or wet conditions. It can develop
in only a few hours.
• The most commonly affected areas are the cheeks, ears,
nose, fingers, and toes.
• Affected area appears as red, swollen skin which is tender,
hot to the touch, and may itch
• Can worsen to aching, prickly (pins and needles) sensation,
then numbness.
• In severe cases, open sores or bleeding lesions may result
from continued exposure.
Chilblains
Treatment
• Warm affected area gently with direct body heat:
– put bare hands over the affected area on the face
– put affected areas against armpits or stomach of another
person
• Do not massage or rub affected areas.
• Do not wet the area or rub it with snow or ice.
• Do not expose affected area to open fire, stove, or any other
intense heat source.
• Seek medical attention to evaluate for tissue damage. Signs
and symptoms of tissue damage may be slow to appear.
Immersion Injury (Trench foot)
Immersion injury (trench foot) results from prolonged exposure
of the feet to wet or damp cool conditions, such as in cold water,
mud, or wet fields, or wearing damp socks. A similar condition of
the hands can occur if a person wears wet gloves for a prolonged
period under cold conditions.
• Usually develops slowly, over hours to
days and at temperatures from 32°F to
50°F.
• Can occur at temperatures as high as 60
degrees F if the feet are constantly wet
• The primary injury is to nerve and
muscle tissue. There is no formation of
ice crystals in the tissues but immersion
injury can cause permanent damage.
Photo courtesy of USACHPPM
Immersion Injury (Trench foot)
Symptoms
• Initially reddened skin, then turns
pale and mottled, finally purple, grey,
or blue
• Tingling pain, itching, burning
sensation, or numbness may occur,
followed by leg cramps and swelling
Note the cyanosis (blueness
of skin) around the nail beds;
redness and swelling; and
blisters.
Photo courtesy of USACHPPM
• May cause permanent damage to the
circulatory system so person is more
sensitive and prone to cold-related
injuries in that area
• May develop blisters, ulcers, and
gangrene. Amputation may be
necessary
Immersion Injury (Trench foot)
Treatment
• Remove wet clothing and replace with dry, warm clothing.
• Warm affected area slowly at room temperature. Carefully
clean, dry, and wrap loosely with sterile dressing, taking care
not to break the blisters. This can lead to infection.
• Elevate feet to reduce swelling.
• Do not walk on injured feet.
• Seek prompt medical attention; trench foot can cause severe
disability.
Immersion Injury (Trench foot)
Prevention
• Keep feet clean and dry.
• Check them regularly; if they get wet from water or
sweat, dry them and replace with dry socks.
• Change socks at least every 8 hours or whenever wet
and apply foot powder. Foot powder with aluminum
hydroxide can help.
• Don’t wear tight socks; this can further impair
circulation.
• Don’t sleep with wet socks.
Resources – for further information
• Canadian Centre for Occupational Health &
Safety: “Cold Environments – Working in the Cold”
http://www.ccohs.ca/oshanswers/phys_agents/cold_working.html
WISHA Consultation Services
Safety & Health program review and worksite evaluation
•By employer invitation only
•Free
•Confidential
•No citations or penalties
•Letter explains findings
•Follow-up all serious hazards
For additional assistance, you can call one of our consultants.
Click below for local L&I office locations:
http://www.lni.wa.gov/Safety/Basics/Assistance/Consultation/consultants.asp
Thank you for taking the time to learn
about safety and health and how to prevent
future injuries and illnesses.