Electrical injuries
Electrical injury is tissue damage from current conducted through the body, marked by a blackened, dry contact wound that can conceal extensive deep muscle and nerve injury despite normal-looking skin. Cardiac dysrhythmia is the immediate threat; rhabdomyolysis with myoglobinuric kidney injury follows. Diagnosis rests on the contact history and electrocardiogram; treatment is scene safety, cardiac monitoring, and crystalloid resuscitation titrated to urine output rather than a surface-burn formula.
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What this article covers
- Overview
Definition: tissue damage from current conducted through the body, ranging from a trivial static discharge to a fatal high-voltage contact.
- Epidemiology
Bimodal age distribution: toddlers sustain low-voltage household exposures, classically biting a live cord and burning the mouth corner, while working-age men sustain occupational high-voltage exposures.
- Risk factors
High-voltage occupational contact: linework, construction, and farm equipment near energized conductors carry the greatest current and deepest injury.
- Pathophysiology
Path of least resistance: current concentrates along nerve, vessel, and muscle, which conduct better than skin, tendon, fat, or bone, rather than spreading evenly through a limb; this is also why the…
- Clinical features
History that changes management: voltage, AC versus DC, contact point and duration, whether the patient fell or was thrown, loss of consciousness, and whether CPR was given at the scene.
- Differential diagnosis
Lightning injury: a single, direct-current-like flashover across the skin rather than sustained conducted current; entry and exit wounds are minimal or absent, keraunoparalysis (cool, mottled…
- Diagnosis
What establishes the diagnosis: a corroborated history of electrical contact plus a discrete, blackened, dry contact wound; no single test confirms the exposure, but each study below quantifies the injury.
- Management
First, ensure rescuer scene safety, then assess: isolate or de-energize the source before anyone touches the patient, then a standard trauma survey with cervical spine precautions given the risk of tetany-induced neck injury.
- Complications
Cardiac dysrhythmia and arrest: immediate; fibrillation is more typical of AC, asystole of DC.
- Prognosis
Voltage, current pathway, and duration of contact are the dominant predictors of death and permanent injury; a transthoracic or transcranial pathway, prolonged AC contact, and cardiac arrest at the scene carry the highest risk.
- Prevention
Ground-fault protection: a residual current device or ground-fault circuit interrupter (GFCI) on wet-area and outdoor circuits trips at about 4 to 6 mA; test the built-in button every 1 to 3 months.
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Related articles
- Rhabdomyolysis
Rhabdomyolysis is necrosis of skeletal muscle with release of myoglobin, creatine kinase, and intracellular electrolytes into the circulation, diagnosed by a serum creatine kinase at least five times the upper limit of normal (typically over 1500 U/L) with a urine dipstick positive for blood but no red cells on microscopy; treatment is aggressive isotonic intravenous fluid to a urine output of 200 to 300 mL/h and correction of hyperkalemia, with acute kidney injury from pigment nephropathy the dominant complication.
- Burns
Burns are thermal, chemical, electrical, or radiation injuries to the skin classified by depth from first to fourth degree, with the fourth most common traumatic injury overall and the highest mortality in patients over 60 years, burns over 40% total body surface area, or inhalation injury. First-line management is primary survey and airway protection, stopping the burning process, and, for burns of 20% total body surface area or more, lactated Ringer resuscitation at 2 mL per kilogram per percent total body surface area with the estimate titrated to urine output.
- Acute kidney injury
Acute kidney injury is a sudden rise in serum creatinine or fall in urine output from prerenal, intrinsic, or postrenal causes, defined and staged by KDIGO criteria. Management targets the underlying cause, corrects volume and electrolyte derangements, and escalates to renal replacement therapy for refractory hyperkalemia, acidosis, volume overload, or uremia.
- Shoulder dislocations
Shoulder dislocation is displacement of the humeral head from the glenoid, most often anterior after a fall or load-bearing injury with the arm held abducted and externally rotated, or posterior after a seizure or electrical injury with the arm adducted and internally rotated. Diagnosis is clinical, confirmed by radiograph, and treatment is prompt closed reduction followed by a sling, with surgery reserved for recurrent instability or an associated fracture.
- Hyperkalemia
Hyperkalemia is a serum potassium level above 5.0 mEq/L, most often from decreased kidney excretion, transcellular shifts, or excess intake, with levels above 6.0-6.5 mEq/L or any ECG change constituting a medical emergency from the risk of fatal arrhythmia. Treatment sequences cardiac membrane stabilization with calcium, transcellular potassium shifting with insulin/dextrose and albuterol, then definitive potassium removal with binders, diuretics, or dialysis.