BURNS

PHYSICAL INJURIES

physical agents that can cause non-kinetic injuries to the body

Heat Cold Electricity

INJURIES DUE TO HEAT

The extent of the damage depends on time of damage and type of tissue

The heat source may be Dry Burn

wet scalding

COLD INJURIES (HYPOTHERMIA)

most deaths from hypothermia are seen in old people and in some children

Predisposing factors to hypothermia Extremes of age Phenothiazine drugs Myxoedema patients drunken people

ELECTRICAL INJURIES

Injury and death from the passage of an electric current through the body

common in both industrial and domestic circumstances.

BURN A burn is a type of

 injury to flesh caused by

 

heat

electricity

chemicals

light

radiation

TYPES OF BURN

Superficial burns 

Partial-thickness burns 

Full-thickness burns 

Mechanisms of Injury

Thermal

Electrical

Chemical

Radiative

PATHOPYSIOLOGY OF BURN INJURIES

Mechanisms of Injury….. Thermal

An electric current will travel through the body from one point to another, creating “entry” and “exit” points. The tissue between these two points can be damaged by the current

The voltage is the main determinant of the amount of heat generated and hence the degree of tissue damage

Mechanisms of Injury….. Electrical

• Low voltages tend to cause small, deep contact burns at the exit and entry sites.

• The alternating nature of domestic current Arrhythmias

Domestic electricity

• The voltage is 1000 V or voltage greater than 70 000 V is fatal

• There is extensive tissue damage and often limb loss.

• Rhabdomyolysis, and renal failure may occur

High tension injuries

• Arc of current from a high tension voltage source

• The heat from this arc can cause superficial flash burns to exposed body parts

“Flash” injury

Acids Coagulation necrosis ( limits burn damage )

Form a thick, insoluble mass where they contact tissue.

Alkalis Destroy cell membrane through

liquefaction necrosis Deeper tissue penetration and deeper

burns

Mechanisms of Injury….. Chemical

Local Response

Zone of Coagulation •Central zone •white or charred •point of maximum damage•coagulation of the constituent proteins causes irreversible tissue loss

Zone of Stasis

•Intermediate zone•Red then white •decreased tissue perfusion• potentially salvageable•↓BP , infection, or edema convert this zone into an area of complete tissue loss

Zone of Hyperaemia •outer zone•Deeper red color•intact circulation•Tissue will recover unless there is severe sepsis or prolonged hypoperfusion

Systemic Response

Asphyxia : which could be 1 -Anoxic anoxia 2- Anemic

Anoxia Stagnant Asphyxia 3- Histototic Anoxia 4-Anemia : due to

1 -Hemolysis RTN 2- B.M depression due to sepsis

GIT ulcersHepatic cetrilobular necrosis

Non-specific down regulation of the immune response occurs, affecting both cell mediated and humoral pathways

SEVERITY OF BURN INJURIES

Severity depends on

The extent

Sex

Age of the

victim

General health

The degree

The site

Individual susceptibi

lity

CAUSES OF DEATH FROM BURNS

Immediate causes

Rapid causes

Delayed causes

Example

Complications

Time To Healing

Sensation

Texture

Appearance Layer

InvolvedNomencl

Ature

None

1wk or less

Painful

Dry

Redness (erythema)

Epidermis

FIRST DEGREE

DEGREES OF BURN

Local infection/cellulitis

2-3wks

Painful

Moist

Red with clear blister. Blanches with pressure

Extends into superficial (papillary) dermis

Second degree (superficial partial thickness)

Scarring, contractures (may

require excision and skin grafting)

Weeks - may pro

gress to thir

d degree

Painful

Moist

Red-and-

white with

bloody blisters

. Less blanchi

ng.

Extends into deep

(reticular)

dermis

Second degree

(deep partial

thickness)

Scarring, contractu

res, amputati

on

Requires excision

Painless

Dry, leathery

Stiff and white/bro

wn

Extends through

entire dermis

(Third degree

(full thicknes

s

Amputation,

significant

functional

impairment

Requires excision

PainlessDry

Charred with

eschar

Extends through

skin, subcuta

neous tissue

and into underlyi

ng muscle

and bone

Fourth degree

•Extent of a Burn:

The extent of a burn is expressed as the total percentage of body surface area (TBSA) affected by the injury. Accurate estimation of the TBSA of a burn is essential to guide management.

Multiple methods have been developed to estimate the TBSA of burns. These methods are not used for superficial burns.the best known method,the rule of nines, is appropriate in use in all adults and when quick assessment is needed for children. 

for small or scattered burns,or for assessing the amount of

unburnt skin in very extensive burns,the person's palmar

surface(including fingers) can be used as a guide.

it is equivalent to around 1% of the person's total body surface area.

For small children, the head represents a greater portionof the body mass than adults. Lund and Browder first described a method for compensating for the differences and the Lund and Browder Chart is used to calculate Body Surface Area (BSA) in children.

If the chart is unavailable, one can estimate body surface area and adjust for age, as :follows

.

In children < 1 year, the head is 18% and each leg is 14%

- The torso and arms the same percentages as in the adult - For each year over 1, add 1/2 percent to earepresent ch leg and- decrease the percent for the head by 1%, until adult values .are reached

1. Blister have amore aquous fluid 2. Change in color of skin

Cherry redCarboxy_hb

Black carbon

particles in larynx

trachea bronchi

Pink

unreduced

oxyhb

POST MORTUM SHANGES

3-Surface of body has been damaged4- blurred margins over joints 5- puterfuction

POST MORTUM SHANGES

CHEMICAL BURNS

Chemical burns can be caused by acids or bases that come into contact with tissue. Both acids and bases can be defined as caustics.

Causes

Acids (Sulfuric acid, Nitric acid, Hydrochloric acid, Phenol and cresols)

Bases (Calcium hydroxide, Ammonia, Sodium hydroxide and potassium hydroxide)

Oxidants (Bleaches and Chlorites, Peroxides, Chromates, Manganates)

Vesicants (sulfur, nitrogen mustards, arsenicals, phosgene oxime )

Other substances (White phosphorus, Metals, Hair coloring agents , Airbag injuries)

Chemical Burn Symptoms

Redness, irritation, or burning at the site of contact Pain or numbness at the site of contactFormation of black dead skin at the contact siteVision changes if the chemical gets into your eyesCough or shortness of breath

Treatment

Prehospital Care1-Prevent contaminated irrigation solution from running onto

unaffected skin.2-Remove contaminated clothes.

Emergency Department Care1-secure the airway2-Large surface burns require the same fluid therapy

Consultations1-Ophthalmologic consultation is recommended for patients with

ocular burns 2-Caustic ingestions may require multiple specialties3-Consult a psychiatrist for cases of attempted suicide

Medication

1- Topical antibiotic therapy is usually recommended for dermal and ocular burns.

2- Calcium or magnesium salts are used for hydrofluoric acid burns.

3- Steroid therapy is controversial for caustic ingestions but may be helpful for treating upper airway inflammation.

4- Non steroidal anti-inflammatory agents provide some degree of pain relief for mild burns by inhibition of prostaglandin mediators.

5- Topical and ophthalmic antibiotics are routinely used for dermal and ocular burns, respectively. The injured tissues lose many of their protective mechanisms and are at increased risk of infection.

Prevention

All chemicals should be stored in a locked cabinet.

Avoid mixing different products that contain toxic chemicals

Avoid prolonged (even low-level) exposure to chemicals

Avoid using potentially toxic substances in the kitchen or around food

It Is important to read and follow label instructions, including any precautions of toxic products .

Never store household products in food or drink containers.

Store chemicals safely immediately after use.

Use paints, petroleum products, ammonia, bleach, and other products that

give off fumes only in a well-ventilated area.

INVESTIGATIONS OF PATIENTS WITH BURN INJURIES:

1-Arterial blood gases2-CBC

3-Chest –x ray4-Kidney function

5-Liver function6-Urine analysis

7-Serum immunoglobulins

MANAGEMENT OF BURN

Assessment of : ABC : airway, breathing, circulation Fluid resuscitation Associated injuries Internal injures or fractures Possible inhalation injury Pre-existing illnesses, drug therapy, allergies and drug sensitivities

MANAGEMENT OF MINOR BURNS

Cleaning .. Blisters .. Dressing

MANAGEMENT OF MAJOR BURNS Airway Stop the burning process Breathing Intravenous access and fluid

replacement Ensure adequate analgesia Prevent hypothermia Management of the burns Transfer to a burns centre or other

appropriate care centre

REFERRAL TO A SPECIALIST BURNS UNIT

1. Age of the patient2. Site of injury3. Inhalation injury4. Mechanism of injury5. Large affected area6. Any patients with traumatic injury 7. Any burned children 8. Third degree burns in any age group