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 partial-

thickness, deep partial-thickness, and full-thickness

• 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 Body Area • Arm 9% • Head 9% • Leg 18%• Anterior Trunk 18%• Posterior Trunk 18%• Perineum 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 ReactionsPhototoxicity

• Appears as exaggerated sunburn

• Mostly caused by systemic medications including tetracycline, furosemide, phenothiazines, fluoroquinolones,

5-FU, and amiodaronePhotoallergy• 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 30minutesThis 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 ReliefANALGESICS: • 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.

•

ULTRAVIOLET RADIATION SPECTRUM

UVA (Longwave Radiation)• 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

• • 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.

• Long-term hazards of skin damage from radiation:– Malignancy:

• Squamous cell epithelioma• Actinic keratosis• Basal cell carcinoma

– Premature aging• 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 anti-inflammatory 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:

• Oral photosensitivity topical photosensitivity • chlorothiazide antifungal• furosemide coal tar • Hydrochlorothiazide sunsueed agent e.g.• -antifungals paraamino benzoic A• Guiseofulvin• -antimicrobial • Quinolones• Sulfonamide • Tetracycline

• 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)

• Sun Protection Factor (SPF) =

MED of Photoprotected Skin

MED of Unprotected Skin– MED is minimum dose of radiation which

produces erythema – SPFs are determined indoors using xenon

lamps which approximate the spectral quality of UV radiation

• effectiveness of SPFs– Factors which influence Difference in skin types.– Thickness of the applied sunscreen.– Time of day.– Altitude: each 1,000 ft increase adds 4% to the intensity

of erythema producing UV radiation; thus intensity is about 20% greater in Pocatello than at sea level.

– Environment: snow/white surfaces reflect 70-90%, and when directly overhead water reflects nearly 100% of UVR.

– 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• 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)• 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).• 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, 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• Minimally effective, absorb UVB spectrum.• Generally used in combination with one of

the above.

HIGH SPF SUNSCREENS

• 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)