Electrical Injury

Key Features

Essentials of Diagnosis

• Resuscitation must be initiated immediately since clinical findings suggesting death are unreliable

• Extent of damage from electrical injury is determined by

  • Type and amount of current

  • Duration of exposure

  • Pathway of electrical current through body

• Skin findings may be misleading and are not indicative of the depth of tissue injury

General Considerations

• With alternating currents (AC) of 25–300 Hz

  • Low voltages (< 220 Hz) tend to produce ventricular fibrillation

  • High voltages (> 1000 Hz) cause respiratory failure

  • Intermediate voltages (220–1000 Hz) cause both

• More than 100 mA of domestic house current (AC) of 110 V at 60 Hz can cause ventricular fibrillation

• Direct current (DC) contact is more likely to cause asystole

• Lightning injuries differ from high-voltage electric shock injuries

  • Lightning usually involves higher voltage

  • It usually has a briefer duration of contact

  • It may cause asystole, nervous system injury, and multisystem pathologic involvement

• Electrical burns are of three distinct types

  • Flash (arcing) burns

  • Flame (clothing) burns

  • Direct heating effect of tissues by the electric current

Clinical Findings

Symptoms and Signs

• May vary from tingling, superficial skin burns, and myalgias to paralysis, massive tissue damage, or death

• Skin damage does not correlate with the degree of injury

  • Not all electrical injuries cause skin damage

  • Only very minor skin damage may be present with massive internal injuries

• Lesions caused by direct heating of tissues are usually sharply demarcated, round or oval, painless yellow-brown areas (joule burn) with inflammatory reaction

• Loss of consciousness

Diagnosis

Laboratory Tests

• Obtain the following immediately

  • Complete blood count

  • Electrolytes

  • Kidney function tests

  • Liver biochemical tests

  • Creatine phosphokinase or urine myoglobin

  • Urinalysis

  • Cardiac enzymes

Diagnostic Procedures

• Obtain an ECG immediately

Treatment

• Pain management with acetaminophen, nonsteroidal anti-inflammatory drugs, opioids

Therapeutic Procedures

Emergency measures

• Separate victim from the electric current before initiation of CPR or other treatments; the rescuer must be protected

• Turn off the power, sever the wire with a dry wooden-handled ax, make a proper ground to divert the electric current, or separate the victim using nonconductive materials such as dry clothing

• Resuscitation must be initiated on all victims of electrical injury since clinical findings are deceptive

Hospital measures

• Evaluate for

  • Hidden injury (eg, ophthalmic, otologic, muscular, compartment syndromes)

  • Organ injury (myocardium, liver, kidney, pancreas)

  • Blunt trauma

  • Dehydration

  • Skin burns

  • Hypertension

  • Acid-base disturbances

  • Neurologic damage

  • Posttraumatic stress disorder

• Fluid resuscitation is important to maintain adequate urinary output (0.5 mL/kg/h if no myoglobinuria is present, 1.0 mL/kg/h if ...