Electrical Injury (Electric Shock)

First aid for an electric shock

1. Do not touch the person while they are still in contact with the current. You could be electrocuted too.
2. Turn off the power at the switch, plug or breaker. If you cannot, and it is low voltage, move the source away with a dry, non-conducting object such as wood or plastic, standing on something dry.
3. For high-voltage lines, stay at least 20 feet (6 meters) away and call 911. Do not approach until the power company confirms it is off.
4. Call 911 or your local emergency number.
5. Check breathing. If the person is unresponsive and not breathing normally, start CPR and use an AED as soon as one is available. Cardiac arrest after an electric shock often responds well to prompt CPR and defibrillation.
6. Protect the spine if there was a fall or strong muscle spasm that threw the person.
7. Cover burns loosely with a clean, dry dressing or cloth. Do not apply ice, butter or ointments.
8. Keep the person warm and lying down.

Lightning strikes

People struck by lightning do not carry a charge and are safe to touch. If several people are struck, help those who appear lifeless first, because they may recover with CPR.

How electricity damages the body

The severity of injury depends on:

• Voltage: high voltage (over 1,000 volts) causes far more severe injury than household current (110 to 240 volts)
• Type of current: alternating current (AC), used in homes, can cause muscles to lock so the person cannot let go, prolonging contact
• Pathway: current crossing the chest (hand to hand, or hand to foot) risks the heart. Current through the head risks the brain
• Duration of contact
• Resistance: wet skin lowers resistance and allows more current through

Bone and fat resist current and heat up, cooking surrounding muscle from the inside. That is why burns may look small at the entry and exit points while muscles, nerves and blood vessels deep inside are badly damaged.

Types of electrical injury

Possible injuries and complications

• Heart: cardiac arrest (ventricular fibrillation), irregular heart rhythms, heart muscle damage
• Skin: entry and exit wounds, flash burns, burns from ignited clothing. See burns
• Muscle: deep muscle death leading to rhabdomyolysis, which releases myoglobin that can cause acute kidney injury
• Compartment syndrome: swelling inside a limb that cuts off blood supply. See compartment syndrome
• Nerves and brain: loss of consciousness, seizures, numbness, weakness, memory and concentration problems, chronic pain
• Eyes: cataracts can develop months or years later, especially after high-voltage injuries to the head
• Ears: ruptured eardrums, particularly with lightning
• Fractures and dislocations from falls or violent muscle contractions
• Mental health: anxiety, depression and PTSD

Hospital assessment

• ECG for everyone with a significant shock, and heart monitoring for people with high-voltage injury, loss of consciousness, abnormal ECG, chest pain or heart disease
• blood tests: creatine kinase for muscle damage, kidney function, electrolytes, and troponin if heart injury is suspected
• urine test for myoglobin
• imaging for fractures and spinal injuries
• eye exam

A healthy adult with a brief household shock, no symptoms, no burns and a normal ECG usually does not need admission.

Treatment

• Cardiac care: treating arrhythmias and monitoring
• IV fluids in large volumes to flush myoglobin and protect the kidneys
• Burn care in a burn center for serious electrical burns
• Surgery: cutting open tight compartments (fasciotomy), removing dead tissue, and sometimes amputation
• Tetanus booster for burns and wounds
• Rehabilitation: physical and occupational therapy, pain management and psychological support

Prevention

• use ground fault circuit interrupters (GFCIs) in kitchens, bathrooms and outdoors
• cover outlets and keep cords out of children's reach
• keep electrical appliances away from water
• stay away from downed power lines
• follow lockout procedures at work
• during thunderstorms, go indoors or into a hard-topped car, and wait 30 minutes after the last thunder

Frequently asked questions

What should you do after an electric shock?

Make sure the power is off before touching the person. Call 911 for anything more than a minor household shock. Start CPR if they are not breathing. Cover burns with a clean dry cloth. Anyone with symptoms, burns or a high-voltage injury needs a hospital assessment.

When should I go to the hospital after an electric shock?

Go to an ER after any high-voltage or lightning injury, loss of consciousness, burns, chest pain, palpitations, breathing difficulty, confusion, numbness or muscle pain, or if you are pregnant or have heart disease. A minor household shock with no symptoms usually does not need hospital care.

Can an electric shock cause delayed symptoms?

Yes. Heart rhythm problems usually appear early, but muscle breakdown, kidney injury and compartment syndrome can develop over hours. Nerve problems, cataracts, memory difficulties and mood changes can appear weeks to months later.

Why are electrical burns more serious than they look?

Electricity travels through the body along nerves, muscles and blood vessels, generating heat deep inside. Skin burns at the entry and exit points may be small, while muscles and nerves beneath are severely damaged.

Can a household electric shock hurt your heart?

It can. Household current that passes across the chest can trigger an abnormal heart rhythm. Most healthy people with a brief shock and no symptoms are fine, but an ECG is advised if there are any symptoms, burns, or heart disease.