Frost bite is an injury caused by freezing of the skin and underlying tissues. In the earliest stage of frostbite, known as frostbit, there is no permanent damage to skin. symptoms include cold skin and prickling feeling followed by numbness and inflamed skin.

1. FROST BITE
VINODHA.R M.SC(N),
TUTOR
SRM TRICHY COLLEGE OF NURSING
TRICHY

2. Introduction
Frostbite is skin damage caused by freezing temperatures below 32
degrees Fahrenheit (0 degrees Celsius). You’re more likely to get
frostbite in any situation that leads to prolonged cold exposure:
During the winter.
In windy weather conditions.
At high altitudes.
If you don’t have shelter from the cold weather.

4. Definition
Frostbite is a skin injury that occurs when exposed to extreme low
temperatures, causing the freezing of the skin or other tissues,
commonly affecting the fingers, toes, nose, ears, cheeks and chin
areas.Most often, frostbite occurs in the hands and feet.

6. Causes
 The major risk factor for frostbite is exposure to cold through
geography, occupation and/or recreation.
 Inadequate clothing and shelter are major risk factors. Frostbite is
more likely when the body's ability to produce or retain heat is
impaired.
 Physical, behavioural, and environmental factors can all contribute to
the development of frostbite.

7. Immobility and physical stress (such as malnutrition or
dehydration) are also risk factors.
Disorders and substances that impair circulation contribute,
including diabetes, Raynaud's phenomenon, tobacco and alcohol
use.
Homeless individuals and individuals with some mental illnesses
may be at higher risk.

9. Mechanism
Freezing
In frostbite, cooling of the body causes narrowing of the blood vessels
(vasoconstriction). Temperatures below −23 °C (−9 °F) are required to form ice
crystals in the tissues.
The process of freezing causes ice crystals to form in the tissue, which in turn
causes damage at the cellular level.
Ice crystals can damage cell membranes directly. In addition, ice crystals can
damage small blood vessels at the site of injury. Typically any temperature below -
0.55C (31F), is required for frostbite to begin to set in.

10. Rewarming
Rewarming causes tissue damage through reperfusion injury, which
involves vasodilation, swelling (edema), and poor blood flow (stasis).
Platelet aggregation is another possible mechanism of injury. Blisters
and spasm of blood vessels (vasospasm) can develop after rewarming.

12. Non-freezing cold injury
The process of frostbite differs from the process of non-
freezing cold injury (NFCI). In NFCI, temperature in the tissue
decreases gradually. This slower temperature decrease allows
the body to try to compensate through alternating cycles of
closing and opening blood vessels (vasoconstriction and
vasodilation).

13. If this process continues, inflammatory mast cells act in
the area. Small clots (microthrombi) form and can cut
off blood to the affected area (known as ischemia) and
damage nerve fibers. Rewarming causes a series of
inflammatory chemicals such as prostaglandins to
increase localized clotting.

14. Pathophysiology
The pathological mechanism by which frostbite causes body tissue injury can be
characterized by four stages: Pre freeze, freeze-thaw, vascular stasis, and the late
ischemic stage.
Prefreeze phase: involves the cooling of tissues without ice crystal formation.
Freeze-thaw phase: ice-crystals form, resulting in cellular damage and death.
Vascular stasis phase: marked by blood coagulation or the leaking of blood out of
the vessels.
Late ischemic phase: characterized by inflammatory events, ischemia and tissue
death.

15. Stages

16. Symptoms of frostbite
Frostnip:
 During frostnip or the first stage of frostbite,
 skin is red to purple or lighter than your natural skin tone.
 skin may also feel cold, slightly painful and tingly.
 small red bumps (chilblains) on your skin.

20. Superficial (surface) frostbite:
 This is the second stage of frostbite, and it requires medical treatment.
 Skin might feel warm, but the water in your skin is slowly freezing into
ice crystals.
 “pins and needles” feeling.
 Skin may sting or swell up.
 Painful, spotty patches or purple or blue areas of skin like a bruise.

22. Severe (deep) frostbite:
In the third stage of frostbite, your lower layers of skin (subcutaneous tissue) freeze
and total numbness sets in.
It can be difficult to move the area that’s frostbitten or you may not be able to
move it normally.
Big blisters will appear on the frostbitten skin a day or two after cold exposure.
Frostbite is dangerous because it often numbs your skin so you may not feel that
anything’s wrong at all.

24. Diagnostic evaluation
History collection
Physical examination

26. Prevention
The Wilderness Medical Society recommends covering the skin and
scalp, taking in adequate nutrition, avoiding constrictive footwear and
clothing, and remaining active without causing exhaustion.
Supplemental oxygen might also be of use at high elevations. Repeated
exposure to cold water makes people more susceptible to frostbite.
Additional measures to prevent frostbite include

29.  Avoiding temperatures below −23 °C (-9 °F)
 Avoiding moisture, including in the form of sweat and/or skin emollients
 Avoiding alcohol and drugs that impair circulation or natural protective responses
 Layering clothing
 Using chemical or electric warming devices

30. Layering clothing

31. Mechanical firing

33.  Recognizing early signs of frostnip and frostbite
 Gently remove your cold weather gear, like gloves or boots.
 You should also remove any jewellery like rings or watches if they’re
near an affected area of skin. If your clothing is wet, put on dry
clothing.
 Place your affected skin in a bath of warm (not hot) water. This will
be a slow rewarming process that can take at least 30 minutes.

34.  Place blankets on your affected area of skin. Don’t wrap
blankets around your skin because it could cut off circulation
and prevent blood flow to your affected tissues.
 Avoid applying heat directly to your skin to prevent burns.

35. If you have signs or symptoms of surface or
deep frostbite,
 Raise your body temperature in lukewarm water or by applying warm, wet packs
to your skin for up to 30 minutes.
 Apply wound dressings to your frostbitten skin with sterile bandages, keeping
your fingers and toes separated to avoid rubbing.
 Test blood flow in the affected area of your body. If you have stage three
frostbite, your provider may also connect you to an IV (a needle that enters a vein
in your arm to deliver fluids) to improve your circulation.
 Give you antibiotics and pain relievers, such as ibuprofen (Advil®, Motrin®).

36.  Rehydrate your body by giving you water (frostbite dehydrates your
tissues).
 Give you oxygen therapy. For extreme frostbite, your provider may
have you breathe pure oxygen inside a pressurized room. This
treatment, called hyperbaric oxygen therapy, helps some people heal
faster by increasing their blood-oxygen levels.

37. Prevention when going outdoor
 Avoid going outside: When it’s cold out, try to stay indoors.
 Limit your trips: If you do have to go outside, try to limit it to 10 or 15 minutes
before going back inside for a few hours.
 Dress warmly before going out: Dress appropriately whenever you know you’re
going to be in cold temperatures. Layer your clothing. Wear warm socks, a thick
hat, mittens and a heavy scarf over your face, ears and mouth.

38.  Wear windproof and waterproof clothing: Wear clothes designed to
keep the weather out and to keep your head and neck area warm.
 Don’t cut off your circulation: Make sure your boots and clothes
aren’t too tight. This can cause poor circulation. Keep moving to
maintain a good blood flow.
 When traveling in cold weather, always bring your phone with you.
It’s your lifeline to medical help if you have an accident or get stuck
on the road. Finally, pack a car emergency kit in your vehicle.

39. Treatment
 The first priority in people with frostbite should be to assess for hypothermia and
other life-threatening complications of cold exposure. Before treating frostbite,
the core temperature should be raised above 35 °C. Oral or intravenous (IV) fluids
should be given
 Blood vessel dilating medications such as iloprost may prevent blood vessel
blockage. This treatment might be appropriate in grades 2–4 frostbite, when
people get treatment within 48 hours. In addition to vasodilators, sympatholytic
drugs can be used to counteract the detrimental peripheral vasoconstriction that
occurs during frostbite.

41.  wound care: blisters can be drained by needle aspiration, unless they are bloody
(hemorrhagic). Aloe vera gel can be applied before breathable, protective
dressings or bandages are put on.
 Antibiotics: if there is trauma, skin infection (cellulitis) or severe injury
 tetanus toxoid: should be administered according to local guidelines.
Uncomplicated frostbite wounds are not known to encourage tetanus.
 pain control: NSAIDs or opioids are recommended during the painful rewarming
process.

42. Surgical intervention
 For severe cases of frostbite, your provider may need to perform surgery to
remove any dead skin and tissue after you heal. It may take days or even months
to determine if you need surgery
 Debridement or amputation of necrotic tissue is usually delayed unless there is
gangrene or systemic infection (sepsis).
 If symptoms of compartment syndrome develop, fasciotomy can be done to
attempt to preserve blood flow.

43. Complications
 Nerve damage (neuropathy).
 Sweating heavily.
 Being more sensitive to the cold.
 Frostbite arthritis, stiffness in your hands and feet.
 Skin discoloration.
 Nail damage or nail loss.
 Scarring.

44. Severe complications
 Gangrene.
 A secondary infection.
 Amputation.
 Damage to your tendons, muscles and bones.

45. Conclusion
Frostbite is a skin injury that occurs when exposed to extreme low
temperatures, causing the freezing of the skin or other tissues,
commonly affecting the fingers, toes, nose, ears, cheeks and chin
areas.Most often, frostbite occurs in the hands and feet.

46. THANK YOU