Electrical Injury — Cardiac Monitoring and Burns

Key Points

• Ensure the electrical source is disconnected before touching the patient.
• Skin burns can dramatically underestimate deep muscle and vascular injury.
• Obtain an ECG after clinically meaningful electrical exposure.
• Not every minor low-voltage exposure requires prolonged cardiac monitoring when the patient is asymptomatic and the ECG is normal.
• High-voltage injury requires evaluation for rhabdomyolysis, compartment syndrome, vascular injury, and occult trauma.
• Treat dysrhythmias by standard resuscitation principles.
• Burn-center consultation should be early for high-voltage or significant electrical burns.
• Always evaluate for secondary trauma from falls, blast effect, or tetanic muscle contraction.

Algorithm

1. Confirm scene safety and disconnect the electrical source before patient contact.
2. Perform primary trauma survey and resuscitate airway, breathing, and circulation abnormalities.
3. Identify voltage when known, current type, contact duration, path through the body, loss of consciousness, and associated fall or trauma.
4. Obtain 12-lead ECG and inspect all skin surfaces for burns and trauma.
5. Place high-risk patients on continuous cardiac monitoring and treat dysrhythmias conventionally.
6. For high-voltage or deep injury, obtain CK, electrolytes, renal function, urinalysis, and serial limb examinations.
7. Provide analgesia, wound care, tetanus prophylaxis, and goal-directed fluids when rhabdomyolysis is present.
8. Consult burn surgery or a burn center for significant electrical burns and surgery urgently for compartment syndrome or major trauma.
9. Assess neurologic deficits and pregnancy-specific needs when relevant.
10. Discharge only low-risk patients with normal ECG and examination, no significant symptoms or injury, and clear return precautions.

Clinical Synopsis & Reasoning

Electrical injury results from current passing through the body, arc injury, flash burn, or a combination of mechanisms. Severity depends on voltage, current type, tissue resistance, contact duration, pathway through the body, and environmental conditions. Alternating current can cause sustained muscle tetany that prolongs contact, while high-voltage exposure can produce deep muscle necrosis, vascular injury, compartment syndrome, and fractures despite relatively small skin wounds. Lightning is a distinct electrical mechanism with unique neurologic and cardiovascular features.

The first priority is rescuer safety. The electrical source must be disconnected before contact with the patient. Once safe, assess airway, breathing, circulation, and traumatic injuries. Cardiac arrest is treated with standard resuscitation. Patients may have been thrown, fallen from height, or sustained forceful muscle contraction, so spinal, orthopedic, and head injury assessment should be mechanism-based. Burns at presumed entry and exit sites should be inspected, but skin findings underestimate deep injury and should never be used alone to grade severity.

A 12-lead ECG is central to risk assessment. Patients with syncope, chest pain, palpitations, abnormal ECG, known transthoracic current path, significant high-voltage exposure, cardiac arrest, or substantial comorbidity require cardiac monitoring. In uncomplicated low-voltage exposure with no loss of consciousness, no cardiac symptoms, and a normal ECG, prolonged telemetry is often unnecessary. High-voltage injuries require broader evaluation for deep tissue and vascular damage, rhabdomyolysis, compartment syndrome, and burn-center consultation.

Neurologic effects range from transient paresthesias and weakness to seizure, spinal cord injury, peripheral neuropathy, and delayed symptoms. Cataract can follow electrical injury involving the head. Pregnancy adds fetal considerations and generally warrants obstetric assessment according to gestational age and exposure severity.

Treatment Strategy & Disposition

After scene safety and standard trauma resuscitation, remove smoldering clothing and jewelry and cool associated thermal burns appropriately without causing hypothermia. Cover burns with clean dry dressings and provide analgesia. Tetanus prophylaxis should be updated when indicated. High-voltage electrical burns, significant deep tissue injury, circumferential burns, compartment syndrome, major trauma, and burns involving specialized areas warrant early consultation with a burn center.

Obtain ECG early. Treat dysrhythmias according to standard advanced life support principles. Continuous monitoring is appropriate for patients with abnormal ECG, arrhythmia, syncope, cardiac arrest, chest pain, high-voltage exposure, or other high-risk features. Troponin is not required in every minor low-voltage shock, but it is reasonable when there are ischemic symptoms, ECG abnormalities, significant transthoracic exposure, or concern for myocardial injury. Echocardiography is reserved for hemodynamic abnormalities or suspected myocardial dysfunction.

For significant muscle injury, measure creatine kinase, renal function, potassium, calcium, phosphorus, and urinalysis. Treat rhabdomyolysis with goal-directed isotonic crystalloid while monitoring urine output and avoiding volume overload. Hyperkalemia can be severe after muscle necrosis and requires immediate standard therapy. Compartment syndrome demands urgent surgical evaluation and fasciotomy when confirmed clinically. Myoglobinuria alone is not an indication for indiscriminate fluid volumes; perfusion and renal risk guide therapy.

Disposition depends on voltage and clinical findings. High-voltage injury, significant burns, neurologic deficit, arrhythmia, syncope, persistent pain, rhabdomyolysis, compartment syndrome, or associated trauma generally requires admission or specialty observation. Patients with a brief low-voltage exposure, normal examination, normal ECG, no cardiac symptoms, no significant burn, and no concerning trauma can often be discharged with return precautions for chest symptoms, neurologic changes, worsening pain, dark urine, or progressive swelling.

Epidemiology / Risk Factors

• Electrical injuries occur in household, occupational, industrial, construction, and lightning settings.
• Low-voltage household current causes many exposures, while high-voltage industrial injuries account for disproportionate tissue destruction.
• Workplace electrical injury often involves falls or arc burns in addition to current passage.
• Children may be injured by household outlets or cords and can have oral commissure burns with delayed bleeding risk.
• Lightning injuries can involve multiple victims and should trigger reverse-triage principles because patients without signs of life may still be salvageable.

Investigations

When to Monitor

Pharmacology

Prognosis / Complications

• Uncomplicated low-voltage exposure with a normal ECG and no symptoms generally has an excellent prognosis.
• High-voltage injury can require repeated debridement, grafting, amputation, or prolonged rehabilitation because deep tissue necrosis evolves.
• Cardiac arrest and severe hypoxic injury worsen prognosis but successful resuscitation is possible.
• Peripheral neurologic symptoms can persist or appear later after the initial injury.
• Functional outcome depends on associated trauma, burn depth, vascular injury, nerve damage, and rehabilitation needs.

Patient Education / Counseling

• Return immediately for palpitations, fainting, chest pain, shortness of breath, new weakness, numbness, dark urine, worsening swelling, or severe pain.
• Explain that deep injury can be greater than the visible skin burn after high-voltage exposure.
• Follow burn wound care and specialty follow-up instructions carefully.
• Workplace injuries may require occupational safety review and documentation.
• Patients with head-pathway exposure should report new visual symptoms because delayed ocular complications can occur.
• Pregnant patients should follow obstetric monitoring recommendations based on gestational age and exposure.

Notes

Electrical injury is best approached as a combined burn, trauma, cardiac, neurologic, and muscle-injury problem. The visible skin lesion is often the least reliable measure of severity. The American Burn Association emphasizes that electrical burns require medical evaluation and may need cardiac monitoring, surgery, and rehabilitation.

For low-voltage exposure, risk stratification should avoid unnecessary admission while still recognizing high-risk features. A normal ECG and absence of symptoms in a truly minor exposure are reassuring; high voltage, loss of consciousness, ECG abnormality, major burn, or deep tissue symptoms are not.

References

1. American Burn Association: Electrical Burns — Link
2. American Burn Association: Advanced Burn Life Support — Link