Electrical Injuries

Essentials

• The patient must be off the circuit before he/she can be safely helped. Switching off high-voltage current should be confirmed by the electricity company. High-voltage electric arc may reach several meters.
• Initial treatment is symptomatic and aims at safeguarding vital functions (securing breathing and circulation; resuscitation if needed).
• The possibility of associated injuries must be taken into account (cervical injury in an unconscious patient, other fractures, damage to the muscles or internal organs).
• Skin burns are treated as usual. Injuries in tissues may be considerably more extensive than the injury visible on the skin. In extensive burns or damage to the internal organs, consult a burn care centre.
• Monitored follow-up in a hospital and further investigations, including troponin I/T and myoglobin/CK, if the patient has been unconscious or if arrhythmias or ECG changes are detected or if the patient is symptomatic after the event.
• Follow-up is not needed if the injury has taken place at a home by low-voltage electricity, the ECG is normal and the patient is asymptomatic.

Exposure to electricity

• The electrical power is determined by Ohm's law.
  • Electrical current I (in amperes, A) = voltage V (in volts, V) / resistance R (in ohms)
  • Resistance of the human body
    • Dry skin 100 000 ohm
    • Moist skin 2 500 ohm
    • Internal organs 500 ohm
• The most dangerous situation is caused by current passing through the heart (hand-to-hand or hand-to-feet) or through the head.
• A current of over 2 000 mA is likely to cause cardiac arrest.
  • High voltage (over 1 000 V, e.g. powerlines of railways, electric masts) may generate an electric arc. It usually causes severe third-degree burns.
• 50-2 000 mA may cause ventricular fibrillation or direct conduction pathway or myocardial damage. Delayed secondary myocardial damage is possible, among others, as a result of a catecholamine storm that is related to an electrical accident.
  • Marks caused by the current may be visible on the skin. The severity of the skin burns depends on the impact time of the current and the circumstances during the contact.
  • Also home current (230 V) is sufficient to cause arrhythmias, burns and e.g. necrosis in fingers.
• 20-100 mA, when continuing, can cause a respiratory spasm. Over a prolonged period (> 1 min), the spasm may cause hypoxia.

Symptoms

Treatment

• Remove the patient from the electric current, preferably by switching off the power supply e.g. using its power switch or by cutting the wires (remember insulated gloves or other insulated clothing!). High-voltage current is cut by the electricity company.
  • Alternating current (AC) causes muscle contractions that easily lead to the person getting stuck to the power source.
• Resuscitation according to protocol if the patient is lifeless. Treatment of Cardiac Arrest in Primary Health Care
• Initial assessment and therapy is symptomatic and aims at safeguarding vital functions with ABCDE principles (securing breathing and circulation).
• The exact description of the event and symptoms should be investigated. Possible burns on the skin, other clinical findings and ECG should be assessed.
• Follow up of cardiac rhythm (monitoring), vein access and, if necessary, starting fluid therapy and, after stabilizing initial treatment, transfer to specialized carein the case of unconsciousness, cardiac arrest, arrhythmia or abnormal ECG or if the patient has symptoms after the event.
• In specialized care, investigations include troponin I/T and myoglobin/CK.
• Follow-up is not needed if the injury is caused by low-voltage electricity (e.g. home electricity), the ECG is normal and the patient is asymptomatic.
• Treatment of skin burns according to usual principles Burn Injuries
  • In large burn injuries, or if you suspect deep injuries, start fluid therapy before the transfer to specialized care.