Electric Shock Overview
An electric shock occurs when a person comes into contact with an electrical energy source. Electrical energy flows through a portion of the body causing a shock. Exposure to electrical energy may result in no injury at all or may result in devastating damage or death.
Burns are the most common injury from electric shock.
Electric Shock Causes
Adolescents and adults are prone to high voltage shock caused by mischievous exploration and exposure at work. About 1,000 people in the United States die each year as a result of electrocution. Most of these deaths are related to on-the-job injuries.
Many variables determine what injuries may occur, if any. These variables include the type of current (AC or DC), the amount of current (determined by the voltage of the source and the resistance of the tissues involved), and the pathway the electricity takes through the body. Low voltage electricity (less than 500 volts) does not normally cause significant injury to humans. Exposure to high voltage electricity (greater than 500 volts) has the potential to result in serious damage.
If you are going to help someone who has sustained a high voltage shock, you need to be very careful that you don't become a second victim of a similar electrical shock. If a high voltage line has fallen to the ground, there may be a circle of current spreading out from the tip of the line. Your best bet may be to call 911. The electric company will be notified so that the power can be shut off. A victim who has fallen from a height or sustained a severe shock causing multiple jerks may have a serious neck injury and should not be moved without first protecting the neck.
Children are not often seriously injured by electricity. They are prone to shock by the low voltage (110-220 volts) found in typical household current. In children aged 12 years and younger, household appliance electrical cords and extension cords caused more than 63% of injuries in one study. Wall outlets were responsible for 15% of injuries.
Electric Shock Symptoms
A person who has suffered an electric shock may have very little external evidence of injury or may have obvious severe burns. The person could even be in cardiac arrest.
- Burns are usually most severe at the points of contact with the electrical source and the ground. The hands, heels, and head are common points of contact.
- In addition to burns, other injuries are possible if the person has been thrown clear of the electrical source by forceful muscular contraction. Consideration should be given to the possibility of a spine injury. The person may have internal injuries especially if they are experiencing any shortness of breath, chest pain, or abdominal pain.
- Pain in a hand or foot or a deformity of a part of the body may indicate a possible broken bone resulting from the electric shock.
- In children, the typical electrical mouth burn from biting an electric cord appears as a burn on the lip. The area has a red or dark, charred appearance.
When to Seek Medical Care
For a high-voltage shock, seek care at a hospital's emergency department. Following a low-voltage shock, call the doctor for the following reasons:
- It has been more than 5 years since your last tetanus booster
- Burns that are not healing well
- Burns with increasing redness, soreness, or drainage
- Any electric shock in a pregnant woman
A person shocked by high voltage (500 volts or more) should be evaluated in the emergency department. It may be prudent to get prehospital care, usually obtained by calling 911. Following a low-voltage shock, go to the emergency department for the following concerns:
- Any noticeable burn to the skin
- Any period of unconsciousness
- Any numbness, tingling, paralysis, vision, hearing, or speech problems
- Difficulty breathing
- Any electric shock if you're more than 20 weeks' pregnant
- Any other worrisome symptoms
Exams and Tests
At the Emergency Department, the doctor's primary concern is to determine if significant unseen injury exists. Injury may occur to muscles, the heart, or the brain from the electricity or to any bones or other organs from being thrown from the electric source.
The doctor may order various tests depending on the history and physical examination. Tests may include any or none of the following:
- ECG to check the heart
- Complete blood count
- Blood or urine test or both for muscle enzymes (would indicate significant muscle injury)
- X-rays to look for fractures or dislocations, both of which may be caused by a near electrocution
- CT scan
Electric Shock Treatment Self-Care at Home
Brief low-voltage shocks that do not result in any symptoms or burns of the skin do not require care. For any high-voltage shock, or for any shock resulting in burns, seek care at a hospital's emergency department. A doctor should evaluate electric cord burns to the mouth of a child.
Treatment depends on the severity of the burns or the nature of other injuries found.
- Burns are treated according to severity.
- Minor burns may be treated with topical antibiotic ointment and dressings.
- More severe burns may require surgery to clean the wounds or even skin grafting.
- Severe burns on the arms, legs, or hands may require surgery to remove damaged muscle or even amputation.
- Other injuries may require treatment.
Next Steps Prevention
Steps to prevent electrical injury depend primarily on the age of people involved.
- For children younger than 12 years, most electrical injuries are caused by power cords. Inspect your power cords and extension cords. Replace any cords that have broken or cracked external covering and any cord that has exposed wire.
- Do not allow children to play with any electrical cord.
- Limit use of extension cords and be sure the cord is rated for the current (measured in amps) that will be drawn by the device being powered.
- Use outlet covers to protect infants from exploring electrical outlets.
- Update old, ungrounded electrical outlets to grounded (3-prong) systems. Replace outlets near any water (sink, tub) with fused (GFCI) outlets.
- In children older than 12 years, most electrical injuries result from exploring and activities around high-power systems. Explain to adolescent children that they should not climb on power towers, play near transformer systems, or explore electrified train rails or other electrical systems.
- Among adults, use of common sense can help reduce electrical injury. People who work with electricity should always check that the power is off before working on electrical systems. Avoid use of any electrical device near water. Be careful of standing in water when working with electricity.
- Use caution when outdoors during a thunderstorm containing lightning. Protect yourself from lightning strikes by seeking shelter in a sturdy building or crouching low and away from trees and metal objects if caught outdoors.
Recovery from electric shock depends on the nature and severity of the injuries. The percentage of the body surface area burned is the most important factor affecting prognosis.
If someone who has received an electric shock does not suffer immediate cardiac arrest and does not have severe burns, they are likely to survive.
Infection is the most common cause of death in people hospitalized following electrical injury.
Media file 1: Electric shock, contact injury to hand. Photograph by Timothy G. Price, MD.
Media file 2: Electric shock burns due to current flow through metal framed glasses. Photograph by Timothy G. Price, MD.
Media file 3: Electric shock injury to the foot. Photograph courtesy of William Smock, MD.
Media file 4: Electric shock injury to the hand. Photograph courtesy of William Smock, MD.
Synonyms and Keywords
electric shock, electrocution, electrical burn, high voltage shock