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Date of last update: 10/20/2017.

Forum Name: Cardiology Symptoms

Question: Passing out by coughing

 nick - Sun Dec 05, 2004 2:50 am

i'm 34 and had an episode aprox. 8 months ago, when i coughed hard from a cold i would pass out. this happened 14 times in one day. i went to the hospital and $3500.00 later i still didn't know what was wrong with me. i haven't had problems until today, i'm getting a cold again. i was driving a car for work and coughed kinda hard to get flem out of my throat and got to the edge of passing out. i was getting tunnel vision, then it cleared up. at least 6 times in 8 hours this has happened today. i haven't yet passed out totally. i'm really concerned about how to avoid these episodes and what to do health wise? i'm active, 6'3", 235lbs and eat normal foods. any help to ease my worries would be greatful.

thank you, nick
 Dr. Yasser Mokhtar - Mon Dec 06, 2004 10:06 am

User avatar Dear Nick,

For the brain to work (so for one not to lose consciousness), it must receive blood from the heart.

The heart is a pump and in order to pump blood out to the tissues including the brain, it has to receive it back from the body.

There are factors that control the blood coming back from the body. One of them is the pressure inside the chest. If the pressure inside the chest is high, the blood is not able to travel against high pressure and no blood reaches the heart and no blood comes out of the heart.

When you cough, the pressure inside the chest rises quite a lot, and if the cough is continuous, this means that the pressure does not have enough time to go down and it rises to an extent that the flow of blood back to the heart is minimal and so the blood being pumped out of the heart to the tissues is minimal also and so the blood reaching the brain in minimal and this means that the brain would stop functioning and one would lose consciousness.

This is called cough syncope.

There is nothing to worry about at this time.

But you have to have precautions especially when you are driving or operating any kind of machinery. If you are driving, and you start coughing vigorously, i would suggest that you stop the car by the side of the road if you can as soon as you feel that you might lose consciousness, and once you are back to your normal status, you can restart driving.

Thank you very much for using our website and i hope that this information helped.

Yasser Mokhtar, M.D.
 nick - Mon Jan 17, 2005 7:20 pm

hi thanks for the info. it makes sense the way you explained it. i'm coming down with another cold and started getting light headed at first, and now its getting more indepth. i have not passed out all the way, losing control of myself,but am really close. i went back to your explaination and read it again, there is one flaw. i'm not coughing vigarously, it's 2 coughs, one small, then the next is larger,but its from the diaphram. it feels like there is stuff deep in my throat and i'm trying to cough it up. do you think it could be something else? do you think i need to work on my cardio? would that reduce the chance of this happening again? thank you for your time.
 Dr. Yasser Mokhtar - Tue Jan 18, 2005 10:24 pm

User avatar Dear Nick,

What you are saying does not contradict that this could be cough syncope.

Thank you very much for using our website and i hope that this information helped.

Yasser Mokhtar, M.D.

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