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Electrical and lightning injuries
In electrical injury the external damage misleads — what is seen on the skin is the "tip of the iceberg", and the current causes deep damage to muscle, vessels and the heart; so every victim gets an ECG, and in high voltage rhabdomyolysis and compartment syndrome are sought; with lightning, a victim in cardiac arrest is treated first.
Why it matters in the exam
Questions separate low voltage (household, below 1000 volts) from high voltage, and alternating current, which causes sustained muscle contraction ("cannot let go") and ventricular fibrillation, from direct current or lightning, which mainly cause asystole. The common question is when monitoring is needed: a patient without symptoms after contact with household voltage, with a normal ECG, no loss of consciousness and no other injury, can be discharged.
In high-voltage injury think of rhabdomyolysis with myoglobinuria and kidney failure, limb compartment syndrome, fractures from contraction or falls, and internal injuries. The Parkland formula is not suitable because it underestimates the damage; fluids are given by urine output, with a higher target when there is myoglobinuria.
Lightning causes distinctive findings: a feather-like skin pattern (Lichtenberg figures) that is not a true burn, transient limb paralysis (keraunoparalysis), eardrum rupture and later cataract. In an event with several lightning victims, "reverse triage" is used: treat first those who look dead, because apnoea may persist after the heart restarts and such victims can be saved with ventilation. A pregnant woman needs fetal monitoring even after a minor injury.
Key points
- Every electrical injury — ECG.
- Low voltage, no symptoms and a normal ECG — discharge.
- High voltage — rhabdomyolysis, compartment syndrome and internal injury; not Parkland.
- Alternating current — VF; lightning — asystole and respiratory arrest.
- Lightning with several victims — reverse triage.
Summary table
| Type | Mechanism | Main risk | Action |
|---|---|---|---|
| Low voltage, alternating current | Sustained muscle contraction | Ventricular fibrillation | ECG; if normal and no symptoms — discharge |
| High voltage | Deep tissue heating | Rhabdomyolysis, compartment syndrome, internal injuries | Monitoring, CK, fluids by urine output, compartment checks |
| Lightning | A brief huge direct current | Asystole and respiratory arrest | Resuscitation and prolonged ventilation; reverse triage |
| Distinctive lightning findings | — | Lichtenberg figures, transient paralysis, eardrum rupture | Reassurance, ear and eye examination |
| Pregnancy | Current passing through the uterus | Fetal injury | Fetal monitoring |
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Sources
- Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9th edition (2020) — Electrical and lightning injuries
- Wilderness Medical Society Clinical Practice Guidelines for the prevention and treatment of lightning injuries, 2014 (2023 update) — Triage and treatment
- European Resuscitation Council Guidelines: cardiac arrest in special circumstances, 2021 — Electrocution and lightning strike
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.