Why is a lightening strike so dangerous??

[AVPU]

I know it can screw up your cardio system and electrical currents, but how? Can it seriously harm you if you have no prior heart condition??

This came up in a BLS class I taught a couple weeks ago. My co-instructor, who's an electrician, answered that lightening doesn't have the amps, just the voltage (or maybe it's the other way around...). My husband (who's a cop) said it's the same reason why taser guns don't have do any lasting damage. Are they the same thing? And if so, why wouldn't tasers hurt you but lightening would? I know lightening kills, I've read about CAs and ground charges and all that. I'm confused!

 

[JPINFV]

This might help. http://www.uic.edu/labs/lightninginjury/treatment.html

 

[AVPU]

Thanks, I'll check it out. And I can't believe I spelled 'lightning' with an E. Who does that??

 

[Foxbat]

I know it can screw up your cardio system and electrical currents, but how? Can it seriously harm you if you have no prior heart condition??

Yes, and it can kill you. I don't know the pathopysiology of it, I guess it somehow messes with your heart's conducting pathways.

This came up in a BLS class I taught a couple weeks ago. My co-instructor, who's an electrician, answered that lightening doesn't have the amps, just the voltage (or maybe it's the other way around...).

Your instructor is wrong. Current and voltage in the lightning itself are very large. We're talking the orders of kilovolts and kiloamperes.
As far as the current in the body of the victim, it can vary significantly depending on body resistance (wet vs dry skin, etc), whether the lightning strikes the body directly or it strikes some object near it, etc.
And it can cause severe burns too.

One interesting thing about lightning strikes is that in the case of mass casualty incident you use reverse triage, i.e. you treat those in cardiac arrest first. With quick defibrillation, you have a pretty good chance of saving them.

 

[AVPU]

Yeah, I read that too, about reverse triage. I missed a question on a JB practice test, nad it was in the explanation. Interesting. I've also read that contrary to popular belief, lightning can and will strike the same place twice.

 

[joeshmoe]

Lightning has both massive voltage, like millions of volts, and massive amperage, like thousands of amps if I remember.

The question for me is how the hell does anyone survive a lightning strike. I suspect the reason people dont suffer more damage is the length of time the current is passing through you.

With a lightning strike its a fraction of a second, where as if you grab a live wire the current(amps) may travel through you for several seconds or longer, creating more extensive burn injuries and tissue damage. This may or may not be the reason, this is just my educated guess. The actual reasons may be more complicated.

I also think in many lightening strikes the actual bolt doesnt pass through the victim, but rather near them, so they arent taking the full brunt. Again this is me spitballing.

I think a taser on the other hand has a high amount of voltage but not much current, although still enough to do more than tickle you.

 

[mycrofft]

If it can blow up a tree, and it can, then it can hurt you.

Also, many bolts don't just lance neatly into one spot in the ground. Truth is, sometimes the bolt moves up and down between the cloud and the ground...and more often it is between clouds and never grounds at all.

Some folks have been stricken more than once. PASS!

 

[Melclin]

The idea of reverse triage seems a ridiculous blanket rule to apply considering that arrests could just as easily be from the extensive damage done by the strike rather than simply an upset electrical conduction system.

Consider the following:

You turn up to a lightening strike which has mysteriously affected more than one person (how I'm not sure, I haven't figured that out). You find one person to be in cardiac arrest, two people with extensive burns to their arms but they are alert and screaming in pain, and the final person has burns to the face, a reduced level of consciousness and has coughed up some carbonaceous sputum. Reverse triage would have you treat the person in cardiac arrest yes?

This seems absurd to me. Firstly, in all likelihood the person has extensive internal injuries from the strike, and even if he didn't, given your response time of how ever many minutes is probably stuffed anyway. There are two people in excruciating pain and one person who is not to far away from losing his airway, that you are ignoring for a lost cause.



A quick google search has found this reverse triage to be supported in the literature by expert opinion only.

EDIT: My point is that, I get the basic idea, and I agree with the possibility that a situation might arise in which it was the best thing to do, but, like the trauma 'golden hour', its a silly blanket rule that I think is/will be applied to literally.

 

[usafmedic45]

Yes, and it can kill you. I don't know the pathopysiology of it, I guess it somehow messes with your heart's conducting pathways.

It's a "cosmic cardioversion", in other words it (in severe cases) does to your heart roughly the same thing as a defibrillation shock would do. Strikes to the head can also cause intracranial hemorrhage such as subdural hemorrhage, etc.

The question for me is how the hell does anyone survive a lightning strike.

Actually it's a ridiculously low mortality rate with most educated guesses placing it between 5-10%. I did research (my first research project actually) with the physician whose site was linked earlier on the accuracy of the reporting of lightning strikes in Florida. Believe it or not there is a serious problem in tracking lightning morbidity and mortality because of two major issues and a few minor ones:
1. Cause of death on the death certificate may not be listed as "lightning strike" especially in cases where the patient dies days or even months after the event.
2. Some people after being struck do not seek medical attention immediately. Yes, you read that right. Some surveys of self-reported survivors indicate that people do not go to the ER or call 911 after being struck and only seek medical attention after the begin to develop non-emergent symptoms (loss of hearing, balance problems, etc)

These two reasons are why- and I am not kidding about this- the National Weather Service uses media reports to track lightning strikes to people both fatal and non-fatal.

As to why most people survive, keep in mind that not all strikes are "direct hits". Even those that are electricity, being what it is, follows the path of least resistance to the ground and that can be along the surface of the skin (not significantly affecting the heart or brain, at least in an acute sense). This surface passage of the electricity is responsible for one of the classic signs of lightning strike which is a fern-like burn pattern called a Lichtenberg figure. They are strangely beautiful and you should look them up.

For the non direct hits, obviously the voltage is much reduced and the chances of survival are far better although this is the scenario through which you wind up with the mass casualty scenario that Melclin seems to have such a problem with.

Firstly, in all likelihood the person has extensive internal injuries from the strike, and even if he didn't, given your response time of how ever many minutes is probably stuffed anyway. There are two people in excruciating pain and one person who is not to far away from losing his airway, that you are ignoring for a lost cause.

Ever seen the autopsy of a lightning strike victim? I've seen two of them and have the reports and photos of another 40 or so. Contrary to your contention, the "massive internal damage" is simply not there and the chances of recovery from electrically induced cardiac arrest are among some of the highest you're going to find. This is in due to a combination of factors: people struck are usually healthy (often athletes), bystander CPR rates are quite high and AEDs are available on-site for many athletic events. Can you point me to a case where a person has produced carbonaceous sputum after a lightning strike? Your inclusion of that in your scenario is yet another example of how little you understand about keraunopathology. Carbonaceous sputum is a sign of the inhalation of the solid products of combustion and not internal burns or any of the other myths you may believe and repeat about lightning. Actually you might be well served to read up on the mechanisms of inhalation injury while you are at it. I'll forward you a couple of review articles if you're interested.


Do you understand now why "reverse triage" is recommended? Pain is a secondary concern and the "about to lose their airway" scenario is very uncommon in lightning pathology. The vast majority of mass casualties cases- rare as they are (hence why it's "expert opinion" guiding care, like so many other things in EMS including general cardiac arrest resuscitation itself for the most part)- have two distinct groups: Walking wounded and the apparently dead. The "apparently dead" are simply the red tags in this scenario and the walking wounded like any other triage situation have to wait.

but, like the trauma 'golden hour', its a silly blanket rule that I think is/will be applied to literally.

But yet, I suppose we are supposed to broadly apply the rationalizations of a paramedic student over those of MDs and other health professionals who have looked at the survival rates of persons suffering cardiac arrest after lightning strike and found them to be very high and the mortality of those who initially survive to be complaining of pain, etc to be very low? Actually I only know of one case where someone "talked and died" after a lightning strike and that person died of a closed head injury (including a skull fracture) after falling off a roof secondary to being struck. Please do not spout off things that are going to hinder the delivery of appropriate and timely medical care to the only critical patients on the scene of a lightning strike. If you only realized how much of what we do in EMS has far less science underpinning it than what you're badmouthing here, you'd probably be quite surprised.

 

[Melclin]

For the non direct hits, obviously the voltage is much reduced and the chances of survival are far better although this is the scenario through which you wind up with the mass casualty scenario that Melclin seems to have such a problem with.

I think you got the wrong idea about my thoughts, although I read my post back and it does come across a bit stronger than I meant it.

Can you point me to a case where a person has produced carbonaceous sputum after a lightning strike? Your inclusion of that in your scenario is yet another example of how little you understand about keraunopathology. Carbonaceous sputum is a sign of the inhalation of the solid products of combustion and not internal burns or any of the other myths you may believe and repeat about lightning. Actually you might be well served to read up on the mechanisms of inhalation injury while you are at it. I'll forward you a couple of review articles if you're interested.

Haha. Yeah my bad, I was just thinking oh airway burns and knocked out a symptom, ignoring the actual cause, quickly looking for a pt who would otherwise die without intervention for the purposes of the scenario. "Carbonaceous sputum is a sign of ...etc" - I realise that, and that it was a stupid example, but a thread is a conversation, not a peer reviewed journal - people trip over their thoughts. Silly mistake.


Do you understand no why "reverse triage" is recommended?

No I didn't. I don't know anything about it, I'd never heard of it until this thread. I wasn't making any other assertions other than that it seemed like a bad idea, followed by why I it seemed that way - the intention being that someone would say yay or nay to my idea and explain why. I'm not sure why you replied like a lecturer arguing that my essay was poorly referenced.

Pain is a secondary concern and the "about to lose their airway" scenario is very uncommon in lightning pathology.

The pain pts existed to flesh out the multicasualty scenario. I don't expect people to treat them first, obviously. I was not aware of the incidence of airway burns in lightning pathology, but it was a (now obviously) flawed attempt to suggest a situation in which you would be effectively killing someone by treating the cardiac arrest victim.

The vast majority of mass casualties cases- rare as they are (hence why it's "expert opinion" guiding care, like so many other things in EMS including general cardiac arrest resuscitation itself for the most part)- have two distinct groups: Walking wounded and the apparently dead. The "dead" are simply the red tags in this scenario and the walking wounded like any other triage situation have to wait.



But yet, I suppose we are supposed to broadly apply the rationalizations of a paramedic student over those of MDs and other health professionals who have looked at the survival rates of persons suffering cardiac arrest after lightning strike and found them to be very high and the mortality of those who initially survive to be complaining of pain, etc to be very low?

Of course not, and the sarcasm, as stupid as my original suggested scenario may have been, is not appreciated.

Actually I only know of one case where someone "talked and died" after a lightning strike and that person died of a closed head injury (including a skull fracture) after falling off a roof secondary to being struck.

Please do not spout off things that are going to hinder the delivery of appropriate and timely medical care to the only critical patients on the scene of a lightning strike.

If you only realized how much of what we do in EMS has far less science underpinning it than what you're badmouthing here, you'd probably be quite surprised.

How does my comment hinder the delivery of care to pt? As I said earlier I think you may have misunderstood my tone (but this may have been my fault), you talk as if I was asserting that I was coming from a position of authority on the matter. I think if I had put a big question mark at the end of my post it would have been clearer.

Language like "seems a ridiculous blanket rule" and "This seems absurd to me" + I thought my edit cleared my position up.

I clarify in the context of you post:

1. I thought it was a silly blanket rule to say, if lightning strike --> reverse the triage order which is what I took reverse triage to mean. If for no other reason than I hate blanket rules.

2. I presented a scenario which illustrated why it seemed that way to me and yes it was an obviously flawed scenario, I didn't give the specifics a moments thought because I was looking for quick way to illustrate the idea in my head which was a concern that "could survive with intervention, but will die without" patient would die while "lost cause" pt got worked on. I see now that my concern was misplaced given the prevalence of severe internal injuries because I mistakenly generalized my understanding of high voltage burns to lightning burns and you are right to point out my mistake.

3. I used terms like "seems" because I didn't know, I just mentioned the reasons it bothered me...putting it out there for someone to comment on. I wasn't writing a new guideline for practice and I don't I have to know everything about the topic to mention that it bothers me because the point of a conversation like this is voice our opinions, knowledge and wisdom; compare and contrast; and then hopefully come out the other side with the people who were mistaken (me), knowing a little more than they did. That's why I'm confused by your indignant response to my posting my initial reaction to reverse triage, despite not fully understand the evidence base for it.

4. Given the facts about lightning injuries that you presented albeit somewhat condescendingly, the kinds of injuries that I thought might happen seem very unlikely and the idea of reverse triage makes more sense to me, so thank you.

 

[mycrofft]

The phenomenon of lightning is hard to generalize, too slippery.

But I agree, electric shock is the most likely origin to yield reversible clinical death. I suspect our waterlogged clothing and wet skin with lots of nice electrolytes (sweat) offers an easier avenue for the juice to follow, like the guy who used to blow himself up with dynamite in a barrel at the fair...energy will follow the easiest route.

I strongly believe many so-called lightning strike victims are near-misses.

Instances have been documented with multiple casualties, usually when they crowd up in a cave or other shelter. More heat effects were reported also (melted metal stuff like zippers, charred clothing).

Oh, on my earlier comment: we don't blow up because we don't have bark. Tree bark will explode off a stricken tree...and tree strikes also yield enough damage to leave permanent scars. I do not know if these are due to electrolysis of the phloem, heat damage, or both. Sincew trees don't sweat, maybe their sap is the best conductor.

Oh, and some other "knowledge" about lightning:
1. If it is so likely to strike you in water, how come after a thunderstorm the lake isn't covered with floating or dead fish? Might be safer to get out of your bolat and swim to shore. I was a boat hand and lifeguard for a summer in the San Berdoo mts and despite multiple days ending in lightning, I never saw it strike the lake. I was very aware because I was the last one off, shooling in the toorists.
2. If it is most likely to strike the tallest tree, how come the tallest tree is still there after decades of storms?

http://www.emtlife.com/showthread.php?t=12941&highlight=lightning+stories

 

[usafmedic45]

Given the facts about lightning injuries that you presented albeit somewhat condescendingly

Sorry...didn't mean to be condescending. I just have heard the same thing about mass casualty lightning strikes from others and it is kind of a pet peeve of mine.

 

[Melclin]

Sorry...didn't mean to be condescending. I just have heard the same thing about mass casualty lightning strikes from others and it is kind of a pet peeve of mine.

Yeah I can see that, sorry for stepping on you toes. I should have been more careful with my language; I am prone to hyperbole, and it was a stupid post post on my part :wacko: .

Anyway, very enlightening thread none the less. I'll be interested to see if it comes up in my mass casualty subject next semester.

 

[AVPU]

There's some good knowledge out there

Thank you all for such good and fact-filled responses. I love this forum. Very 'enlightning'....get it??!!

 

[Owenscott]

I have not seen this answer in above text ... direct lightning strike where the bolt passes thru the pt, lets say head to toe, will cause the electrical signals in the heart to be messed up. If electricty passes between two fingers and the heart isn't in the "loop" cardiac usually wont be an issue.

The other thing with lightning is with great amps comes great power to overcome the resistance in our bodies ... i believe causing great heat which then causes our cells to rupture by boiling. As above poster pointed to others he has studied these things and i have not .... just speaking generically.

 

[Needles17]

Well put. I find it interesting that most people hit once are eventually hit again in their lifetime.

 

[mycrofft]

I sincerely doubt MOST folks struck once are stricken again.

But if you are, you will make the news, documented or not.

 

[MRE]

This came up in a BLS class I taught a couple weeks ago. My co-instructor, who's an electrician, answered that lightening doesn't have the amps, just the voltage (or maybe it's the other way around...).

To be honest, electricians generally don't know much about electricity. They know about electrical code and installation.

The other thing with lightning is with great amps comes great power to overcome the resistance in our bodies ... i believe causing great heat which then causes our cells to rupture by boiling. As above poster pointed to others he has studied these things and i have not .... just speaking generically.

Thats not quite true. Very simply, Ohm's law says that Current is equal to Voltage divided by Resistance. This means for a set resistance you need higher voltage to deliver higher current.

Where people get confused is in situations like the taser, which uses high voltage but does not end up flowing high current through a person. What is happening there is that the entire path of current, either between surface contacts or through 40 ft of tiny wires to probes embedded in the skin, the resistance is very very high, and although you apply high voltage, the resulting current is high enough to cause involuntary muscle movement but not cardiac arrest (in most cases).

The same goes for a 12V car battery. With a low resistance path the battery can deliver several hundred amps, however it is safe to touch both terminals with dry skin because the even though the resistance it sees is the same as a taser with surface contacts, at only 12V the current that results is too small to feel. Lick your fingers and touch the terminals and with the reduced resistance you will probably get enough current for a nice tingly feeling.

 

[usafmedic45]

I find it interesting that most people hit once are eventually hit again in their lifetime.

Care to back that up with some credible evidence? I'm pretty familiar with the statistics and have never heard that.

 

[Scout]

Care to back that up with some credible evidence? I'm pretty familiar with the statistics and have never heard that.

I think it comes from if you get hit multiple times you have been hit once. But if you never get hit you wont be hit multiple times. Then just adapt that slightly.