Environmental Emergencies 213

ELECTRICAL BURNS, ELECTROCUTION AND LIGHTNING STRIKE

2 AC is more dangerous than DC and may induce tetanic muscle spasm. The
longer the duration of contact, the greater the potential for injury.
(i) Gripping the electrical source by hand will prevent release and
worsens the injury.

3 Low-voltage electrical injury causes local tissue necrosis with a contact
surface burn that is often full-thickness. The underlying thermal tissue
damage may be extensive and include blood vessels and muscle. There may
be a similar exit (earthing) burn.

4 Arrhythmias (including VF) and unconsciousness may occur if the charge
crosses the heart or brain.
5 Attach a cardiac monitor and pulse oximeter to the patient. Perform a
12-lead ECG.

6 Request a computed tomography (CT) head scan if there is coma, confusion
or focal neurological signs.

MANAGEMENT

1 Manage cardiac or respiratory arrest as for cardiopulmonary resuscitation
(see p. 2).

2 Ot her wise, give ox ygen and aim for an ox ygen saturation over 94%.

3 Give i.v. normal saline for any hypotension, aiming for a urine output of
100 mL/h if there is evidence of myoglobinuria (tea-coloured urine with a
false-positive urine dipstick test for blood).

4 Treat muscle pain with simple analgesia such as paracetamol 500 mg and
codeine phosphate 8 mg.
5 Admit patients with an abnormal ECG or history of arrhythmias for cardiac
monitoring.

6 Discharge the patient if there is no history of altered consciousness or cardiac
arrhythmia, and the neurological state and ECG are normal, provided there
is no significant thermal soft-tissue burn.
(i) A lethal delayed cardiac arrhythmia is exceptionally rare in a
patient with no initial history of an arrhythmia.

High-voltage electrocution

DIAGNOSIS

1 These injuries occur from electric shocks sustained from sources >1000 V
such as electrical cables and power stations. These are serious injuries, and
often fatal.

Warning: electrical burns may look deceptively innocent. A white blister or

small area of broken skin can cover extensive deep-tissue damage requiring

admission to hospital. Always look for the entry and exit wound.

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