About 10% of people who are struck by lightning die because the heart stops beating and breathing stops.
In some people who survive severe lightning injury, an electrocardiogram Electrocardiography Electrocardiography (ECG) is a quick, simple, painless procedure in which the heart’s electrical impulses are amplified and recorded. This record, the electrocardiogram (also known as an ECG)... read more is done to monitor the heartbeat, and blood or imaging tests are needed.
Once the person is resuscitated, burns and other injuries are treated.
Lightning delivers a massive electrical pulse over a fraction of a millisecond. Electrical current passing through the body generates heat, which burns and destroys tissues. Burns can affect skin and sometimes internal tissues. The brief duration of the exposure frequently limits the damage to the outer layer of skin. In addition, lightning is much less likely to cause internal burns than electrical injuries Electrical Injuries An electrical injury occurs when a current passes through the body, interfering with the function of an internal organ or sometimes burning tissue. Often the main symptom is a skin burn, but... read more from generated electricity. However, it can kill a person by instantaneously short-circuiting the heart. Lightning can also damage the nervous system, including the brain, causing seizures Seizure Disorders In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more , loss of consciousness Fainting Light-headedness (near syncope) is a sense that one is about to faint. Fainting (syncope) is a sudden, brief loss of consciousness during which the person falls to the ground or slumps in a... read more , or other abnormalities.
Lightning is the second most frequent cause of storm-related deaths in the United States, resulting in about 30 deaths and several hundred injuries each year. Some injuries result in permanent disability.
Lightning tends to strike tall or isolated objects, including trees, towers, shelters, flagpoles, bleachers, and fences. A person may be the tallest object in an open field. Metal objects and water do not attract lightning but easily transmit electricity once they are hit. Electricity from lightning can travel from outdoor power or telephone lines to electrical equipment or telephone lines inside a house.
Lightning can injure a person in several ways:
After a person has been struck by lightning, the heart may stop beating (cardiac arrest Cardiac Arrest and CPR Cardiac arrest is when the heart stops pumping blood and oxygen to the brain and other organs and tissues. Sometimes a person can be revived after cardiac arrest, particularly if treatment is... read more ) or may beat erratically. When the heart stops or beats erratically, breathing often stops. The heart may beat again on its own, but if breathing has not restarted, the body is deprived of oxygen. The lack of oxygen and, possibly, nervous system damage can cause the heart to stop beating again.
Brain injury usually causes loss of consciousness Fainting Light-headedness (near syncope) is a sense that one is about to faint. Fainting (syncope) is a sudden, brief loss of consciousness during which the person falls to the ground or slumps in a... read more . If brain damage is severe, coma Stupor and Coma Stupor is unresponsiveness from which a person can be aroused only by vigorous, physical stimulation. Coma is unresponsiveness from which a person cannot be aroused and in which the person's... read more may develop. Typically, the person awakens but does not remember what happened before the injury (amnesia Amnesia Amnesia is total or partial loss of the ability to recall experiences or events that happened in the preceding few seconds, in the preceding few days, further back in time, or after the event... read more ). The person may be confused, think slowly, and have difficulty concentrating and remembering recent events. Personality changes may occur and can be permanent.
The eardrums are often perforated. Many eye injuries can develop, including cataracts Cataract A cataract is a clouding (opacity) of the lens of the eye that causes a progressive, painless loss of vision. Vision may be blurred, contrast may be lost, and halos may be visible around lights... read more . Often both legs become temporarily paralyzed, blue, and numb (keraunoparalysis). The skin may show no marks at all or may have minor burns that have a feathering, branching pattern, consist of clusters of tiny pinpoint spots like a cigarette burn, or consist of streaks where sweat has been turned into steam. Numbness, tingling, and weakness may develop because the nerves branching out from the spinal cord have been damaged (peripheral neuropathy).
Lightning injuries are often witnessed, but they may also be suspected when a person is found outside unconscious or with amnesia during or shortly after a thunderstorm.
In the hospital, electrocardiography Electrocardiography Electrocardiography (ECG) is a quick, simple, painless procedure in which the heart’s electrical impulses are amplified and recorded. This record, the electrocardiogram (also known as an ECG)... read more (ECG) may be done if injury is severe (for example, if a person collapsed and may have had a temporary cardiac arrest). The ECG, when done, determines whether the heart is beating normally. Sometimes blood tests or imaging tests Overview of Imaging Tests Imaging tests provide a picture of the body’s interior—of the whole body or part of it. Imaging helps doctors diagnose a disorder, determine how severe the disorder is, and monitor people after... read more , such as computed tomography (CT) or magnetic resonance imaging (MRI), are needed.
During the thunderstorm season, listening to weather reports, which is particularly important for organizers of outdoor events, can help in deciding whether to cancel outdoor activities and in planning for any emergencies that may develop.
High winds, rain, and clouds may mean that a thunderstorm is imminent. By the time thunder is heard, the observers are already in danger and should be seeking safe shelter, such as a large habitable building or a fully enclosed metal vehicle (for example, a car, van, or truck) with the windows closed. Sheltering in a small open structure, such as a gazebo, is not safe. It is not safe to resume outdoor activities until 30 minutes after the last sound of thunder is heard or lightning is seen.
To prevent lightning injuries when indoors, people should avoid contact with plumbing or electrical wiring or using any hard-wired device, including a telephone, computer, video game console, or headsets attached by a cable to a sound system. Being away from windows and doors increases safety, as does turning off and unplugging electrical equipment before the thunderstorm arrives. Cellular telephones, tablet and laptop computers, and music players are safe when used with battery power only, because they do not attract lightning.
About 10% of people with lightning injuries die. The only cause of death is cardiac arrest Cardiac Arrest and CPR Cardiac arrest is when the heart stops pumping blood and oxygen to the brain and other organs and tissues. Sometimes a person can be revived after cardiac arrest, particularly if treatment is... read more and cessation of breathing at the time of the injury. People whose heartbeat and breathing resume survive. If memory of recent events is impaired or thinking is slow, the person may have permanent brain injury. Keraunoparalysis usually resolves within several hours, although the person may occasionally be left with weakness or clumsiness. People with nerve injury often have long-term problems, including chronic pain, sleep difficulties, and erectile dysfunction Erectile Dysfunction (ED) Erectile dysfunction (ED) is the inability to attain or sustain an erection satisfactory for sexual intercourse. (See also Overview of Sexual Dysfunction in Men.) Every man occasionally has... read more .
A person struck by lightning does not retain electricity, so there is no danger in providing first aid. People without a heartbeat and who are not breathing need cardiopulmonary resuscitation First-Aid Treatment Cardiac arrest is when the heart stops pumping blood and oxygen to the brain and other organs and tissues. Sometimes a person can be revived after cardiac arrest, particularly if treatment is... read more (CPR) immediately, including both chest compressions and artificial respiration. If an automated external defibrillator is available, it should be used (see figure Automated External Defibrillator: Jump-Starting the Heart Automated External Defibrillator: Jump-Starting the Heart Cardiac arrest is when the heart stops pumping blood and oxygen to the brain and other organs and tissues. Sometimes a person can be revived after cardiac arrest, particularly if treatment is... read more ). A person who regains a pulse but still is not breathing needs continued artificial respiration because the respiratory muscles may stay paralyzed after the heartbeat returns. Emergency medical assistance should be called. Many people struck by lightning are in good general health and are more likely to recover if given timely CPR Standard CPR Cardiac arrest is when the heart stops pumping blood and oxygen to the brain and other organs and tissues. Sometimes a person can be revived after cardiac arrest, particularly if treatment is... read more .
Burns and other injuries are treated as needed. If resuscitation efforts are not successful within the first 20 minutes, they are unlikely to be, so resuscitation efforts are then stopped.