Lightning is a powerful, brief electrical discharge in the atmosphere, occurring between clouds, within clouds, or between a cloud and the ground. The air around a lightning flash can heat rapidly to temperatures around 30,000°C (54,000°F), much hotter than the sun’s surface. While common, lightning’s interaction with the human body leads to immediate and profound biological consequences. This article explores how lightning impacts the human body and the injuries that can result.
How Lightning Interacts with the Body
Lightning can affect a person through several mechanisms. A direct strike, though less common, occurs when a person becomes part of the main lightning discharge channel. Part of the current moves over the skin (flashover), while another part travels through internal systems like the cardiovascular and nervous systems.
A side flash occurs when lightning strikes a taller object nearby, and current jumps from that object to a person, often when seeking shelter under a tree. Ground current is another common mechanism, where lightning strikes the ground or an object, and energy travels outward along the surface. This current enters the body at one point, moves through, and exits at another, affecting a larger area.
Conduction injuries happen when lightning travels through metal surfaces or wires, passing to a person in contact with that metal. This can occur indoors (e.g., electrical outlets, water faucets) or outdoors. These diverse pathways mean lightning can inflict harm even without a direct hit.
Immediate Physical Injuries
When lightning strikes, immediate physical injuries can be severe, affecting cardiovascular and respiratory systems. Cardiac arrest is a frequent and often fatal consequence, as immense electrical energy overrides the heart’s natural rhythm. Respiratory arrest can also occur. If breathing stops but the heart continues, lack of oxygen can lead to secondary cardiac arrest.
Burns are common, though often superficial, due to rapid heating and vaporization of sweat or moisture on the skin. These can appear as linear burns, tracing sweat paths or resembling cigarette burns. Lichtenberg figures, distinct fern-like patterns on the skin, are characteristic of lightning strikes but are not true burns; they are superficial bruising from capillary damage. Deep tissue burns are less common than with other electrical injuries because of lightning’s brief duration.
Blunt trauma is another immediate injury, as the concussive force of superheated air or powerful muscle contractions can throw a victim. This can lead to fractures, dislocations, or internal organ damage. The shockwave can also cause barotrauma, damaging air-containing structures like ruptured eardrums.
Neurological and Sensory Impacts
Lightning strikes frequently cause neurological and sensory impairments, affecting central and peripheral nervous systems. Brain injuries are common, ranging from temporary disorientation and confusion to lasting conditions such as memory issues and amnesia. Survivors often experience problems with concentration, verbal memory, and new learning, resembling traumatic brain injury symptoms. While imaging may not always reveal structural damage, neurological symptoms are prevalent.
Nerve damage, or neuropathy, can manifest as weakness, numbness, or tingling sensations (paresthesias). Keraunoparalysis, a temporary paralysis specific to lightning victims, often impacts lower limbs more than upper limbs and typically resolves within hours. This paralysis can be accompanied by sensory loss and a pale, cool appearance of the affected limb due to vasoconstriction.
Sensory organs are vulnerable. Ocular injuries are common, with cataracts being a frequent delayed complication developing months after the strike. Vision problems include retinal damage or temporary blindness. Hearing loss is a widespread immediate effect, often due to ruptured eardrums in over 50% of victims. Tinnitus (ringing in the ears) and vertigo are also reported, indicating damage to the auditory and vestibular systems.
First Aid for Lightning Strike Victims
Providing immediate first aid to a lightning strike victim can improve their chances of survival. Lightning strike victims do not retain an electrical charge and are safe to touch. The first step is to call emergency services immediately. People struck by lightning may experience cardiac arrest, and rapid response is vital.
If the victim is unconscious, not breathing normally, or has no pulse, immediate cardiopulmonary resuscitation (CPR) should be initiated. Chest compressions are paramount to circulate blood and oxygen. If an automated external defibrillator (AED) is available, use it.
While waiting for medical help, assess for other injuries like burns or blunt trauma. Treat visible burns and keep the person warm. If there are multiple victims, prioritize those not breathing or pulseless, as they have the highest chance of survival with immediate intervention. Continue monitoring the victim until emergency personnel arrive.