Voltage vs current clinical pearl

Contributor: Travis Barlock, MD

Educational Pearls:

• Quick Statistics on Electrical Burns: Electrical burns compose roughly 2 to 9% of all burns that come into emergency departments.
• The majority of patients who receive electrical burns are male, typically aged 20's to 30's, accounting for 80 to 90% of all electrical burn victims.
• The majority of burns are linked to occupational exposure.
• The upper extremities are more commonly impacted by electrical burns, accounting for 70 to 90% of entry points into the body during an exposure.

What are some of the key considerations in electrical burns?

• Unlike chemical or fire/heat related burns, electrical burns have the potential to cause significant internal damage that may not be physically appreciated externally.
• This damage can include, but is not limited to:
  • Cardiac dysthymias (PVCs, SVT, AV block, to more serious ventricular dysrhythmias such as ventricular fibrillation or ventricular tachycardia).
  • Deep tissue injury resulting in rhabdomyolysis from the initial surge of electricity
  • Rare cases of compartment syndrome

What are the treatment considerations for patients who suffer electrical burns?

• Remembering that cutaneous findings associated with burns may underestimate the severity of the injury, with deeper structures being more likely to be involved as the voltage of the burn injury is directly correlated to severity.
• Manage the patient's airway, breathing, and circulation as always, and conduct further workup into potential cardiac involvement with EKGs, as well as analysis of the extremities where entry occurred for muscle breakdown and compartment syndrome.

Clinical Pearl on Voltage and Current:

• Voltage can be thought of being equivalent to pressure in a fluid/liquid system. Higher voltages are equivalent to higher pressures, but the ultimate damage delivered to the system is from the rate of delivery/speed of the electrical energy surging (current) through the body.
• Current is dependent on the tissue it is travelling through, with different tissues having differing electrical resistances. Tissues like the stratum corneum of the skin and the human bone confer the most resistance (thus lower current) whereas skeletal muscle confers lower electrical resistance (thus higher current) due to water and electrolyte content, which is why injuries like rhabdomyolysis are possible and increase with increasing voltage.

References

1. Khor D, AlQasas T, Galet C, et al. Electrical injuries and outcomes: A retrospective review. Burns. 2023;49(7):1739-1744. doi:10.1016/j.burns.2023.03.015
2. Durdu T, Ozensoy HS, Erturk N, Yılmaz YB. Impact of Voltage Level on Hospitalization and Mortality in Electrical Injury Cases: A Retrospective Analysis from a Turkish Emergency Department. Med Sci Monit. 2025;31:e947675. doi:10.12659/MSM.947675
3. Karray R, Chakroun-Walha O, Mechri F, et al. Outcomes of electrical injuries in the emergency department: epidemiology, severity predictors, and chronic sequelae. Eur J Trauma Emerg Surg. 2025;51(1):85. doi:10.1007/s00068-025-02766-1
4. Faes TJ, van der Meij HA, de Munck JC, Heethaar RM. The electric resistivity of human tissues (100 Hz-10 MHz): a meta-analysis of review studies. Physiol Meas. 1999;20(4):R1-10. doi:10.1088/0967-3334/20/4/201

Summarized by Dan Orbidan, OMS2 | Edited by Dan Orbidan and Jorge Chalit, OMS4

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