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thickness burns.

liquid, such as

Exposure ro thicker liquids or

boiling water,

immersion causes a deeper burn

grease, or tar

from increased contact time.

Immersion burns commonly cover a

larger total body surface area than

do spills.

Flame burn

Flame exposure

Often causes superficial and deep

from fire or

partial-thickness burns.

flammable

Associated with carbon monoxide

liquids, or

poisoning.

ignition of

ciorhing

Flash burn

Explosion of

Often causes partial-thickness burns.

flammable

Burns may be distribured over all

liquid, such as

exposed skin.

gasoline or

Associated with upper airway thermal

propane

damage.

Most common in the summer and

associated with [he consumption of

alcohol.

Contact burn

Exposure to hot

Often causes deep partial- or fullobjects, such as

thickness burns.

glass, plastic,

Associated with crushing injuries,

mecal, or coal

such as moror vehicle accidents.

Most common cause of serious burns

in the elderly.

Sources: Data from GO Warden, OM Heimbach. Burns. In SI Schwartz (ed), Principles

of Surgery, Vol. 1 (7th ed). New York: McGraw-Hili, 1999; and RF Edlich, JC Moghrader. Thermal Burns. In P Rosen (cd), Emergency Medicine Concepts and Clinical Practice, Vol. I (4th cd). Sr. Louis: Mosby, 1998.

damage accounts for the high incidence of amputation associated

with electrical injury.'" The severity of an electrical burn depends

primarily on the duration of contact with the source, as well as the

voltage of the source, rhe type and parhway of currenr, and the

amperage and resistance through the body tissues·

BURNS AND WOUNDS 443

Electrical burns are characterized by deep entrance and exit

wounds or arc wounds. The entrance wound is usually an obvious

necrotic and depressed area, whereas the exit wound varies in presentation. The exit wOllnd can be a single wound or multiple wounds located where the patient was grounded during injury.7 An

arc wOllnd is caused by the passage of current directly between

joints in close opposition. For example, if the elbow is fully flexed

and an electrical current passes through the arm, burns may be

located at the volar aspect of the wrist, antecubital space, and

axilla.'

Complications specific to electrical injury include the following"s:

• Cardiovascular: Cardiac arrest (ventricular fibrillation for electric current or asystolic for lightning), arrhythmia (usually sinus tachycardia or nonspecific ST changes) secondary to alterations in

electrical conductivity of the heart, myocardial contusion or infarction, or heart wall or papillary muscle rupture

• Neurologic: Headache, seizure, brief loss of consciousness or

coma, peripheral nerve injury (resulting from ischemia), spinal

cord paralysis (from demyelination), herniated nucleus pulposus,

or decreased attention and concentration

•

Orthopedic: Dislocations or fractures secondary to sustained

muscular contraction or from a fall during the burn injury

• Other: Visceral perforation or necrosis, cataracts, tympanic

membrane rupture, anxiety, depression, or post-traumatic stress

disorder

Lightning

Lightning, considered a form of very high electrical current, causes

injury via four mechanisms9:

1.

Direct strike, in which the person is the grounding site

2.

Flash discharge, in which an object deviates the course of

the lightning current before striking the person

3.

Ground current, in which lightning strikes the ground

and a person within the grounding area creates a pathway for the

current

444 AClITE CARE HANDBOOK FOR PHYSICAL n-iERAI}ISTS

4.

Shock wave, in which lightning travels outside the person

and static electricity vaporizes moisture in the skin

Chemical Burns

Chemical burns can be the result of reduction, oxidation, corrosion, or

desecration of body tissue with or without an associated thermal injury.lo

The severity of burn depends on the type of chemical and its concentration, duration of contact, and mechanism of action. Unlike thermal burns, chemical burns significantly alter systemic tissue pH and metabolism. These changes can cause serious pulmonary complications (e. g. , airway obstruction from bronchospasm, edema, or epithelial sloughing) and metabolic complications (e. g., liver necrosis or renal dysfunction

from prolonged chemical exposure).

Ultraviolet and Ionizing Radiation Burns

A sunbun1 is a superficial partial-thickness burn from the overexposure

of the skin to UV radjation. Ionizing radiation burns with or without

thermal burn occur when electromagnetic or particulate radiation energy

is transferred [Q body tissues, resulting in the formation of chemical free

radicals. I I Ionizing radiation burns usually occur in laboratory or industrial settings. The severity of the ionizing radiation burn depends on the dose, dose ra te, and the tissue sensitivity of exposed cells. Often referred

to as acute radiation syndrome, complications of ionizing radiation

burns include the following I L

• Gastrointestinal: Cramps, nausea, vomiting, diarrhea, and bowel

i chemia

•

Hematologic: Pancytopenia (decreased number of red blood cells,

white blood cells, and platelets), granulocytopenia (decreased number

of granular leukocytes), thrombocytopenia (decreased number of

platelets), and hemorrhage

• Vascular: Endothelium destruction

Burn Assessment and Acute Care Management

of Burn lnjury

Classificatioll of a Bllm

The extent and depth of the burn determine its severity and dictate

acute care treatment.

BURNS AND WOUNDS 445

Assessing the Extent of a Burn

The accurate assessment of the extent of a burn is necessary to calculate

fluid volume therapy and is a predictor of morbidity.

12 The extent of a

burn injury is referred to as total body sur(ace area (TBSA) and can be

calculated by the rule of nines or the Lund and Browder formula.

Rille o( Nilles

The rule of nines divides the body into sections, seven of which are

assigned 9% of TBSA. The anterior and posterior trunk are each

assigned 18%, and the genitalia is assigned 1% (Figure 7-4). This

\ Front 18% !

\ Back 18% :

18%

18%

Figure 7-4. The rule of nines method of assessing the extent of a bum injury.

(\vith permission (rom M \Valsh led!, Nurse Practitioners: Clinical Skills and

Pro(essionallssltes. Oxford, UK: Butterworth-Heinemann, 1999;32.)