Treatment
Principles
Monitoring
The
first principle of treatment is making the diagnosis
of an electrical injury.
Any
patient with an entrance and exit wound due to an
electrical burn requires hospital admission.
These findings are pathognomonic of the
passage of a significant amount of current.
Since there is absolutely no way of ruling
out deep injury on initial assessment, admission and
observation are necessary.
Cardiopulmonary
monitoring and supportive care are clearly necessary
given the high incidence of cardiac arrhythmias and
pulmonary dysfunction.
An initial urinalysis is essential not only
to verify adequate renal perfusion, but also to
check for myoglobinuria which, if present, will
require special management.
Blood gases and acid-base balance are of
particular importance in avoiding an acidosis that
will accentuate pigment deposition in the kidney.
Monitoring
of peripheral perfusion and palpation of muscle
compartments are of particular importance because of
the concern of the development of compartment
syndromes due to underlying muscle edema.
Compartment pressure can be monitored using
several types of available systems.
Fasciotomy
Indications for fasciotomy
Tissue pressure more than 40 mmHg
Tissue pressure within 30 mmHg of diastolic
pressure
Usually
the number itself is not used as an absolute
indication but is compared with any clinical
evidence of nerve compression, i.e., tingling,
increased pain, decreased sensation, or vessel
compression. Thus
signs of increased pressure include:
Compartment
syndrome
Decreased peripheral pulse
Evidence of nerve compression
Onset of paresthesias
Decreased sensation or increased pain
Increased muscle turgor to palpation
Motor
nerve dysfunction is more difficult to assess given
the fact that muscle damage may be impossible to
distinguish from nerve damage.
Excessive tissue turgor is the single most
useful sign of underlying muscle damage and the need
for fasciotomy.
Fluid
Management
The
same basic principles of fluid management apply as
with a thermal burn alone.
The primary resuscitation fluid is Ringer’s
lactate solution.
There is no formula, however, to assist in
management due to the unpredictable nature of the
underlying tissue damage.
In
general, the fluid requirements per percent of burn
are 1.5 to 2 times that of a skin burn alone given
the nature of the added soft tissue injury.
The
rate of fluid administration is based on the
amount necessary to maintain adequate perfusion
using the same guidelines as for burn shock
management. The
exception is the presence of urine myoglobin or
other evidence of early renal impairment.
If the urine is red or reddish black, a
massive myoglobin release from muscle has occurred
and an increased washout of the tubular pigment is
needed. A
urine flow of 1 cc/kg/hr or more is needed until
pigment load has decreased.
Mannitol (12.5 g every 2 to 4 hours) is often
required to maintain this level of output.
In addition, sodium bicarbonate is often
needed to maintain urine pH equal to or greater than
7 in order to minimize pigment precipitation.
Treatment
Give
Mannitol 25 g bolus followed by 12.5 g every 2 to 4
hours in addition to fluids until pigment
clears from urine
Add
sodium bicarbonate to intravenous solution to
maintain urine pH
>7
but avoid increasing blood pH
>
7.5
Low-dose
dopamine if excessive fluids required plus Mannitol
to maintain urine flow.
Burn
Wound Management
A
skin burn is common as a result of a flash flame
on clothes catching fire or high heat release.
Burn wound management is the same as
previously described.
Escharotomy-Fasciotomy
In
general, if there is a circumferential deep burn
And any evidence of impaired distal perfusion,
i.e., decreased pulses, an escharotomy is
necessary. If
there is also a concomitant electrical injury to
underlying tissue and increasing compartment
pressure, as evident from increased myoglobin,
rigid muscle compartments, or nerve or vessel
compression, i.e. tissue pressure (>
35 to 40 mmHg), fasciotomy is indicated.
Fasciotomy incisions are performed in the
long axis of the limbs, as with the escharotomy.
The
fasciotomy incisions must split the investing
fascia of all the involved compartments.
The underlying muscle can then be inspected
to determine viability.
Electrocautery is often necessary with
fasciotomy as opposed to escharotomy because
fascial and muscle vessels will probably be
patent.
Transfer to Burn Center
Any
high tension injury is a major burn, especially in
the presence of muscle damage.
Transfer is indicated.
LOW TENSION ORAL BURNS
Pathophysiology
Low-voltage
electricity is the leading cause of electrical
injury in children, especially 1 to 2 years old.
Sucking an extension cord is responsible
for more than half of the injuries, and biting on
an electric cord accounts for about 30%.
The most common mechanism is the production
of an electrical arc by the bared wires conducted
by the childs saliva.
Intense local heat is generated, producing
severe local destruction of the mouth tissues.
The local mouth burn is characteristically
grayish-white in color and indented at the center
due to tissue necrosis.
Severe swelling then develops as venous
thrombosis impedes blood return.
The oral burn may involve the lip, tongue,
or oral mucosa and underlying bone.
The most frequent site is the lip, in
particular the commissure area between upper and
lower lips. The
edema of the lips may be intense, impairing
control of saliva
The orbicularis oris muscle is frequently
involved, further impairing control.
Edema subsides over the next 5 to 10 days
and local necrotic tissue begins to slough.
Bleeding from the labial artery is a common
occurrence (20%) during the period of slough (7 to
21 days) and should be anticipated.
Granulation tissue then develops, followed
by collagen deposition and wound remodeling.
Local adhesions and microstomia may develop
over a period of 3 to 5 months.
Injury to the underlying bone will result
in dental abnormalities over time.
Pathophysiology
·
Local
generation of high temperature from current in mouth
·
Intense
local edema (5 to 10 days), impaired muscle function
·
Sloughing
of necrotic tissue (1 to 3 week period) with
bleeding from labial artery: common
·
Scar
formation, adhesions, remodeling 3 to 5 months
Treatment
Initial
hospitalization is recommended to treat the local
burn and observe for any current related injuries.
Tetanus prophylaxis is necessary, but
systemic antibiotics do not appear to be
particularly beneficial.
Local wound care with gentle washing
followed three to four times daily by local
application of a petroleum-based antibiotic
ointment.
