Transcript sun burn for students presentation - Home

MINOR BURNS AND
SUNBURN
Burns
• Can be caused by thermal, electrical,
chemical, or UV radiation exposure
• More than 80% of burns occur in the home
• Extent of injury is function of temperature
and duration of exposure.
• Cell damage occurs as a result of protein
denaturation
Classification of Burns
• Classified primarily according to depth
• Classification as first, second, or third degree is
obsolete
• Replaced by superficial, superficial partialthickness, deep partial-thickness, and fullthickness
• The American Burn Association classifies burns as
minor, moderate, or severe using depth, location,
cause of burn, and body surface area (BSA) as
criteria.
Assessing the area and degree of
burns
• :
• Burns are usually describe and evaluated on the basis of
the area of the body affected and depth of penetration of the
burn in the skin. This helps determine the necessary
treatment regimen and weather self treatment, physician
outpatient treatment or hospitalization is required.
• The "rule of nine" is a rapid method of estimating the
percentage of the body Surface involved in a burn wound.
• .The body surface is divided in to 11 areas; each
representing about 9 % of the total
Rule of nines
• Arm
• Head
• Leg
• Anterior Trunk
• Posterior Trunk
• Perineum
Body Area
9%
9%
18%
18%
18%
1%
Superficial Burns
• Involves only the epidermis
• Redness, warmth, and slight
edema
• Usually no blistering
• May be painful because sensory
nerve endings are intact
• Most sunburns are classified as
superficial
• Most can be treated in outpatient
setting or through self care.
• Will heal within 3 to 6 days
Superficial Partial-Thickness Burns
• Damage to the outer
epidermal layer
• Often moist and weeping,
painful blistering
• Will blanch with pressure
• Painful and sensitive to
temperature and air
• Healing occurs within 2 to 3
weeks
• Small burns (1-2% BSA) of
this type can be treated
through self care
Deep Partial Thickness Burns
• Damage to the dermis layer
• May appear as patchy white to
red area
• Large blisters may be present
• May take up to 6 weeks to
heal
• Patients should be examined
in a hospital emergency room
immediately
Full Thickness Burns
• Dermis and epidermis destroyed
• Skin appears dry, leathery that is painless, insensate
• Wound may initially appear red but will fade to white over
24 hours
• Healing occurs over months and hospitalization is
normally required.
• Infection of burns:
• Burned skin is a good culture medium for
microorganisms since:
• there is much necrotic tissue ,
• defense mechanisms are impaired by he occluded
vascular circulation
• -infection by gram +ve bacteria (staphylococcus,
streptococcus) occurs during the first day. After the
third day, gram –ve bacteria (mainly pseudomonas)
predominate and can convert a second degree burn
to third degree. Topical therapy with silver
sulfadiazines, silver nitrate or antibiotics is
essential.
• Treatment of burns
•
Minor burns:
• They include first or second degree burn of less than
15 % of the body surface.
• These can be treated on outpatient basis.
•
Application of local anesthetics to alleviate pain and
antimicrobial agents to prevent secondary infection, are
the basic element to treatment such burns. They should
in suitable dosage forms.
• Ointments, because of their greasy base facilitate
microbial contamination, and require removal before
further local treatment can be given.
• Creams, solutions and sprays are easier to remove and,
by cooling relief pain.
• Severe burns: 50 % third degree. Thus require
hospitalization where massive I.V. fluid are given,
invasion controlled, recovery problem treated, skin
skin grafting and rehabilitation of he patient is
performed.
•
• Over treatment of burns by applying substances or
chemical other than the readily available, and
valuable cold water is dangerous because of
difficulty of removing contaminatioues for further
treatment (e.g. skin grafling by surgeons). Toxic
chemical may be absorbed or may cause allergic
hypersensitivity reactions. The residue of chemicals
may favor the growth of microorganisms.
• Ingredients of OTC:
• Local anesthetics e.g. benzocaine (0.5-20%) in
burns with disrupted skin, lower concentration
could be used (no penetration resistance)
• Antimicrobials:
• Compounds:
• -QUAT (quaternary ammonium)
• - benzalkonium chloride
• -phenols and topical antibiotics
• -mix of neomycin, polymyxin B sulfate and
bacitracin
Photosensitive Reactions
Phototoxicity
• Appears as exaggerated sunburn
• Mostly caused by systemic medications
including tetracycline, furosemide,
phenothiazines, fluoroquinolones,
5-FU, and amiodarone
Photoallergy
• Relatively uncommon and appears as
intensely pruritic eczematous dermatitis
• Caused by sulfonamides,
phenothiazines, thiazide diuretics,
piroxicam, and cosmetics that contain
certain fragrances.
When to Refer
• Burns on the ears, eyes, face, hands or perineal
areas
• Electrical, chemical, or inhalation burns
• Burn area 2% or more of BSA and consists of
superficial partial thickness or greater injury
-Should reevaluate burn 24 to 48 hours after
injury (after inflammatory response evolves)
• Patients who are immunocompromised or at high
risk for infection (diabetic, advanced age, etc)
Treatment Goals
• Relieve pain
NSAIDs, ASA, APAP and cool down burn area
• Provide a physical barrier
Skin protectants, lubricants, bandages
• Reduce chance of scarring and infection
Cleansing, lubricants, antimicrobials
First Aid and Alleviation Measures
• Superficial and superficial partial thickness burns
Soak in cool water (no ice) for 10 to 30minutes
This decreases vasodilation, lowering redness,
edema, and may prevent blisters.
Gently cleanse area using bland soap—do not
use alcohol or hydrogen peroxide
• Sunburns
Avoid further exposure. Cool compresses or bath
for relief
Watch for heat stroke. : fever, confusion,
weakness, convulsions
Pain Relief
ANALGESICS:
• NSAIDs, ASA
Good for pain and the edema
Good for minor sunburn, especially in first 24
hours after overexposure
• APAP will not help with the inflammation, but ok
for pain.
• Hydrocortisone 1% as an anti-inflammatory
Broken skin increases risk of infection, higher dosages
retard wound healing. Not FDA approved for minor burns.
Topical Anesthetics
• Inhibits transmission of pain signals from pain
receptors.
-Apply no more than 3-4xs/day to small areas
-Provides only 15-45 minutes of relief
-Ointment appropriate for intact skin, creams
are best for broken skin
• Benzocaine 5-20%. About 1% of the population
has hypersensitivity reaction, but no systemic
toxicity
• Lidocaine 0.5-4% has a lower population reaction
but adverse side effects possible from systemic
absorption
Skin Protectants
• Protect the skin from mechanical irritation, drying
of the stratum corneum, and makes wound less
painful
• Should prevent dryness and provide lubrication
• Allantoin 0.5%
• Cocoa Butter 50-100%
• Petrolatum and white petrolatum 30-100%
• Vitamin A and D can be useful, but no proof
orally.
Superficial Burn Treatment
• Skin is intact so there is a low chance of infection.
• Topical “exudates” as physical protection can be
used.
• Dressings or films that are self adhesive, water
proof and semi-permeable. If see through can see
the wound without dressing change. (Tagoderm®)
• Skin protectants
• Cold compresses, external anesthetics, topical
corticosteroids and oral pain relievers.
Superficial Partial Thickness Treatment
• Unbroken skin
Do not disturb blisters!!! They are protective
of the skin below the blister.
• If broken/debrided: May become infected so
cleanse 1-2x’s/day to remove dead skin. Do not
pull on skin!
• Cleanse with bland soaps or surfactants and water
1-2xs/day
• First aid antiseptics or antibiotics sufficient
• Dressing and skin protectant should be used
Finally…..
If there is no improvement in 7 days,
go see a physician!
• Sunburn (dermatitis actinica)
• It is acute inflammatory skin reaction resulting
from sunburn or drug photosensitization caused by
chemicals unusual sensitivity (persons suffering
hypersensitivity)
• Ultraviolet light is responsible for sunburns and
suntan and increases in the risk of the basal cell
carcinoma and malignant melanoma.
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ULTRAVIOLET RADIATION
SPECTRUM
UVA (Longwave Radiation)
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Range 320-400 nm
Erythrogenic activity is weak, however penetrates
dermis
Responsible for development of slow tan tttl tan
Most drug-induced photosensitivity occurs in
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Uv is divided into three ranges:
UVA
320-400 nm (augment the effects of
UVB)
UVB
290-320 nm
UVC 100-290 nm
UVB is the primary cause of sun burning.
Premature aging and development of skin cancer.
-One of the body defence is the production of
melanin (a pigment that result in darkening of the
skin. individuals variability in melanin production
and taning depends on: skin color and genetic
factors.
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Long-term hazards of skin damage from
radiation:
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Malignancy:
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Squamous cell epithelioma
Actinic keratosis
Basal cell carcinoma
Premature aging
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nevus, seborrheic keratosis, solar lentigo
wrinkles, lines, etc
• Sunscreen is cosmetic formulations that
block UV rays.
• Sunscreen is assigned sun protection factors
or SPF, ratings that are supposed to indicate
the level of the protection from UV radiation.
• Sunburns: is an inflammatory alteration of
normal skin that occurs following an
excessive exposure to natural or artificial
sunlight
• Sunburns are redness, pain, as skin heals ---skin will peel within one weak and itching.
• Prolonged exposure second degree burn.
Blistering of the skin, severe pain
accompanied by prostaglandin release nausea
and vomiting, so non steroidal antiinflammatory will ameliorate the condition.
• Multiple exposure premature aging and may
lead to skin cancer.
• Suntanning darkening of the skin in response to
exposure to UVB. The darkening is caused by, an
increased release of the pigment melanin in to the
cells of the skin which is produced by the
melanocytes cells (which is present in the basal
layer of the skin epidermis and protects the body by
absorbing harmful solar radiation .
• Photosensitivity:
• Is an abnormal reaction in the skin exposed to sun. It
may be caused by numbers of substances that come
in contact with the skin or are taken orally examples:
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Oral photosensitivity
chlorothiazide
furosemide
Hydrochlorothiazide
-antifungals
Guiseofulvin
-antimicrobial
Quinolones
Sulfonamide
Tetracycline
topical photosensitivity
antifungal
coal tar
sunsueed agent e.g.
paraamino benzoic A
• Photosensitivity is classified into phototoxic
reaction and photo allergic.
• The two reactions involve the presence of:
photo sensitizer plus sun and UVR
• . Phototoxic -Non immunogenic 2 to 6 hour
after exposure -Immediate reaction depends
on the concentration of the photo sensitizer causing a sun burn type Y reaction
• Photoallergic - occurs only in the people
previously sensitizer by a photoallergen Typically occurs after 24-48 hours (delayed
reaction) after sun exposure.- Not
concentration dependent. The two reactions
are confined to the sun exposed areas, face,
neck hands and legs
• Sunscreen preparation:
• They are topical preparations that block the
effect of the UVR on the skin by: either
absorbing, reflecting or scattering UVR.
• They are divided into physical and chemical
sunscreens (on the basis of their
mechanisms of actions)
• Chemical sunscreens -they are aromatic
compounds conjugated with a carbonyl
group -these chemical absorb high intensity
UV with excitation to a higher energy level.this energy will be dissipated and converted
to the ground state in the forms of
(florescence , phosphorescence and chemical
reaction)-so, they contain agents that absorb
UV spectrum of coverage Disadvantages:some are a photosensitize e.g. amino benzoic
acid and benzophenons
• Physical sun screens -they affect or scatter
UV radiation -they are opaque -reflect ,
absorbed or scatter-they have broad spectrum
-acts a physical barrier
Disadvantages:Cosmetically unacceptable as
they are visible, difficult to remove and
discolor clothes e.g. titanium dioxide and
zinc oxide (reflects and scatters UV visible
light)
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Sun Protection Factor (SPF) =
MED of Photoprotected Skin
MED of Unprotected Skin
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MED is minimum dose of radiation which
produces erythema
SPFs are determined indoors using xenon
lamps which approximate the spectral quality of
UV radiation
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effectiveness of SPFs
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Factors which influence Difference in skin types.
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Thickness of the applied sunscreen.
Time of day.
Altitude: each 1,000 ft increase adds 4% to the intensity
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of erythema producing UV radiation; thus intensity is
about 20% greater in Pocatello than at sea level.
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Environment: snow/white surfaces reflect 70-90%, and
when directly overhead water reflects nearly 100% of
UVR.
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Vehicle: determines skin penetration of sunscreen.
• Uses:
• - Sunscreen agents prevent and protect cell
carcinoma in animals
• -regular uses in human protect the skin forms:
• Actinic keratosis , solar elastosis ,squamous cell
carcinoma and -also prevent people sufferings
from drug phosphosensitivity
• ome will retain effect for 80 minutes i.g. very
water resistance
• -Evaluation of sunscreens: FDA evaluate them
for their SPF and substantively
• Substantively:
• Refers to the ability of the product to adhere to the
skin in the presence of sweating and swimming.
• Water resistance products is essential for
returning their photo protective effect up to 40
minutes of active immersion in water (
How we will increase substantively
• 1- It is either function of the formulations
itself (sunscreen agail)
• Recently, they introduce into the molecules
of the agent, a sulfonium or quarternary
ammonium function group to bind with the
negative group sites of the epidermis.
• Reservoir type sunscreen (penetrates and
acts as a reservoir)
• 2- SPF: the sun protective factor has been developed as a
means of numerically identifying the efficiency of various
sunscreen products and to provide for consumers a guide to
the suitable products for particular types of the skin.
• The SPF has been defined as:
• The ratio between MED in protective skin (protect by the
sunscreen protect) to the MED in the unprotected skin
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MED in the protected skin
• SPF = ------------------------------------•
MED in unprotected skin
• The larger SPF, the greater the protection the sunscreen can
confer.
• It reflects how long one can safely remains in the sun.
• N.B higher SPF than 30 will not
recommended as they require an increased
amount of active ingredients which may
irritate the skin and not provide much mare
protection
• -Evaluation of sunscreens: FDA evaluate them for
their SPF and substantively
• Substantively:
• Refers to the ability of the product to adhere to the
skin in the presence of sweating and swimming.
• Water resistance products is essential for retuning
their photo protective effect up to 40 minutes of
active immersion in water (
Sun screen agents
PABA (Para-aminobenzoic acid)
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Very effective in the UVB range (200-320 nm).
Most effective in conc of 5% in 70% ethanol.
Maximum benefit when applied 60 min prior to exposure
(to ensure penetration and binding to stratum corneum).
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Does NOT prevent drug/chemical-induced photosensitivity
rxn.
Contact dermatitis can develop.
May produce transient drying/stinging from alcohol
content (may be alleviated by adding 10-20% glycerol).
PABA Esters (Padimate A, Padimate O,
Glyceryl PABA)
• Also very effective in UVB range (280-320)
• Most effective in conc. 2.5-8% in 65%
alcohol
• May penetrate less effectively than PABA
• Similar application and adverse effect
• Less staining
Benzophenones (oxybenzone, dioxybenzone,
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sulisobensone)
Slightly less effective than PABA.
Absorbs from 250-400 nm spectrum (ie, UVA &
UVB).
Combined with PABA or PABA ester improves
penetrationand is superior to either agent used alone
(200-400 nm wavelength coverage).
Beneficial in preventing photosensitivity rxns.
Contact dermatitis is rare.
Cineastes and Salicylates
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Minimally effective, absorb UVB spectrum.
Generally used in combination with one of
the above.
HIGH SPF SUNSCREENS
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Can achieve higher SPF by combining two
or more agents.
SPF 30 (3%) vs 15 (6%) of radiation
penetrating skin.
• Physical sunscreen agent: protect against UVA +
UVB therefore they classified as broad spectrum
agent e.g. :
• Titanium dioxide and zinc oxide
• Titanium dioxide is ideal, chemically inert safe,
reflect full UV spectrum
• -by micronizing the element, it will be less viscible
on the skin surface (broad spectrum agent)
• -they are opaque and therefore less cosmetically
acceptable than chemical sunscreens
• -usually, they are applied over limited areas (e.g.
the nose and lips)