0071643192.pdf

ENVIRONMENTAL EMERGENCIES

COMPLICATIONS

■ Coagulopathy

■ Acidosis

■ Cardiac arrhythmias

■ Rhabdomyolysis

An 18-month-old female presents after sustaining an electrical injury while

chewing on a power cord. On examination, there is a burn present to the

corner of her mouth without marked tissue loss or evidence of other intra-

oral burns. What is the most feared complication in this patient?

This child has sustained a local arc burn to the commissure of the mouth. There

is a risk for delayed bleeding in 3–14 days as a result of injury to the labial artery.

ELECTRICAL INJURY

Ohm’s Law: Current = Voltage/Resistance.

■ Voltage= Difference in electrical potential between two points in an elec-

trical circuit. High voltage = ≥1000 V.

■ Current= No. of electrons moving at any time, measured by amperage (A).

■ Resistance= Property of the medium through which electrons pass, measured

in ohms

■ Current flows through “path of least resistance”

■ Decreases with ↑fluid content (eg, nerves, blood vessels, wet skin)

■ Increases with calloused skin

There are two basic types of electrical circuits:

Alternating current (AC)

■ Typical household current

■ Changes its direction of current flow at a given frequency

■ More dangerous than DC at any given voltage

■ 1–4 mA →tingling sensation.

■ 8–22 mA (the “let go” threshold)→tetanic muscle contraction →one

cannot release the electrical source.

■ >70 mA →cardiac depolarization and possible VF.

Direct current (DC)

■ Batteries and electronics

■ Tends to throw the victim from the source →secondary traumatic injuries

Overall, high-voltage electrical injury is characterized by minimal external

findings hiding extensive internal tissue damage.

SYMPTOMS/EXAM

■ Immediate cardiac arrest may occur from asystole or ventricular fibrillation

(primary cause of death).

■ Patients who survive the initial electrical shock present with a variety of

injuries depending on path of current flow and associated trauma.

■ Loss of consciousness, confusion, amnesia

If VF develops: Defibrillate

once, then hold until core

temperature >32°C.

AC is more dangerous than

DC at any given voltage.

Decreasing order of electrical

resistance: Bone, fat, tendon,

skin, muscle, mucous

membranes, blood vessels,

nerves