An estimated 200 people die each year in the U.S. after being struck by lightning. An extremely brief but intense hit delivers more than 10 million volts and is fatal in about 30 percent of cases. Recent lightning strikes in Newark resulted in one death and three injuries.
Most survivors have significant complications. Half of people struck by lightning will suffer rupture of the tympanic membrane in the ear. Many go on to develop cataracts.
âLightning presents a grave risk of death,â warns Shreni Zinzuwadia, M.D., an emergency department physician at UMDNJ-The University Hospital and instructor of surgery at the UMDNJ-New Jersey Medical School. âCardiac or respiratory arrest may result from being hit by lightning.â
There are other dangers outside of a direct hit, she added, from three additional types of strikes.
A side strike happens when lightning jumps from its initial point of contact to the victim. âFor example, if you seek protection under a tree, which is one of the worst places to be during a storm, the lightning can hit the tree then jump to you, a better conductor of electricity since humans are mostly salty water,â she explained. âThis kind of strike can kill the tree and the person.â
A contact strike occurs when lightning hits an object the person is holding or wearing, such as a watch or eyeglasses.
The other type of strike – step potential â happens when a current traveling through the ground goes up your leg, travels through you and then goes down the other leg and back into the ground. âThat is why Boy Scouts practice standing on one leg during a storm,â she explained. âThey are attempting to decrease the likelihood that the current will go through them by having only one foot on the ground.â
Prevention begins by seeking cover at the start of a storm. âLightning seems to be concentrated at the forefront of a storm,â according to Zinzuwadia, âso there tends to be a greater risk of being hit by lightning at the beginning of a storm.â
According to the Federal Emergency Management Agency (FEMA), part of the U.S. Department of Homeland Security (DHS), individuals who hear thunder roar should go indoors because no place outside is safe when lightning is in the area. Stay indoors until 30 minutes have passed after you hear the last clap of thunder.
Once inside, FEMA advises that people avoid contact with corded phones and electrical equipment or cords; do not wash your hands, take a shower, wash dishes, or do laundry because plumbing and bathroom fixtures can conduct electricity; stay away from windows and doors; stay off porches; and do not lie on concrete floors or lean against concrete walls.
If you are outside during a storm, crouch down and try to touch as little of the ground as you can, Zinzuwadia suggests. âEven if you are hit by the current, the less contact there is between you and the ground, the less likely it is that all of your major organs will be hit,â she says. âIt increases your chances of survival.â
What signs might indicate that a person has been struck by lightning? âYou may see superficial burns on the skin or clothing may burst into flames or be torn away from the body,â Zinzuwadia said. âA person may fall to the ground.
âPeople who are hit by lightning commonly die from ventricular fibrillation, asystole (cardiac arrest), or respiratory arrest,â Zinzuwadia added. âBystanders should immediately check for a pulse and spontaneous breathing.â
Immediately call 911 for help if someone is hit by lightning, Zinzuwadia emphasizes.
If a person is in respiratory arrest â has a pulse but is not breathing – provide rescue breaths until the victim resumes spontaneous breathing.
If the victim goes into cardiac arrest, where the heart just stops due to the impact of the massive electrical current, CPR should be administered, Zinzuwadia said. âGive cardiac compressions and provide respiratory support for them.â
Source : http://www.sciencedaily.com/releases/2009/08/090805193601.htm
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