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Fainting Spells: Why Do You Feel Faint?

By Edited Nov 13, 2013 0 3

Fainting Spells: Why Do You Feel Faint?
Credit: http://www.tumblr.com/tagged/fainting%20spell

I hate feeling faint.  So far I've only suffered from that condition twice in my lifetime, but both times the fainting spells took place at the top of a flight of stairs.  The end results were not pretty, and I hated the damage that it did to my body.  Even more I hated not knowing what had caused these two spells.  I mean, there had to be something horribly wrong with my body to have caused my two little swan dives off the stairs right?  

So I called my doctor and told him what had happened. Lucky me there was an appointment vacancy that had opened recently, so I took it.  My doctor and I had a very long conversation about what can cause fainting spells, and which were the most likely to be important in my case.  We then proceeded to test for each one of them until we knew which one was the most likely culprit of these episodes.  

Main Causes of Fainting Spells

It turns out that fainting spells occur when the necessary amounts of glucose or oxygen can not reach the brain.   This can be caused by a number of things but it essentially breaks down into only a couple of basic groups.  

     1.  Hyperventilation

     2. Low Blood Pressure

     3. Blood problems

     4. Blood vessel or Heart problems




By hyperventilation, the doctor was asking me if I was... well... hyperventilating.  In other words was I gulping in too much oxygen and getting rid of too much carbon dioxide rapidly.  This normally happens to people when they are anxious or are in the middle of a panic attack. This results in an imbalance in the pH of your blood.  You see your blood is very slightly acidic and our bodies have to be careful to keep up the right pH.  If you end up gulping are it actually makes your blood become even more acidic, so much so that it becomes dangerous.  Your body makes you faint so that it can get a chance to fix this imbalance.  In this case it's literally a safety mechanism for overriding a panicked brain. This one was easy to drop from the list.  

Blood Pressure

Since the general goal of your cardiac system is to make sure that blood can reach your extremities, your blood pressure is incredibly important.  While most people will at some point in their lives have either high or low blood pressure, many times people don't consider the potential problems that it can cause, and fainting spells are just one of them.  

Low blood pressure (hypotension) is the one that directly causes fainting in people suffering from it.  The main symptoms of low blood pressure are light-headedness, dizziness, and fainting.  The reason this happens is because the amount of pressure being used on the blood isn't adaquate to push it to the places in the body that it needs to go to.  

Low Blood Pressure
Credit: http://www.medicinenet.com/low_blood_pressure_hypotension_pictures_slideshow/article.htm

Blood Problems

There are a couple of problems that can happen inside the blood that can result in fainting spells.  The first and easiest problem to get is dehydration.  Yet another reason to drink lots and lots of water.  

Now what does dehydration have to do with your blood being able to function properly?  It boils down to the fact that a large part of your blood is water.  Essentially your blood is a mixture of liquids and solids.  When you are dehydrated you are messing with the liquid half of your blood and making it unbalanced.  It becomes more difficult for your blood to circulate through your body when you don't have enough liquids in your system, and that inability to deliver glucose to your brain is what results in feeling faint.

Another issue with your blood composition that can result in a faint is if your anemic.  Now there are over 400 types of anemia, (like sickle cell anemia, Iron-deficiency anemia, Pernicious anemia, and Trauma related anemia are the 5 most common) and in all cases it deals with your red blood cells.  the basic problem is that their is a problem, either rooted in a lack of iron, blood loss, or various other problems that result in a failure to carry enough oxygen to your internal organs.  That lack of oxygen can cause a person to faint.  

Blood Vessels & Heart Problems

When their are problems with your blood vessels it can directly interfere with the flow of blood to your brain.  The first one that comes to mind is a heart arrhythmia, or a blood clot.  These however are not the only things that can cause it.  It could be a heart block, which is when there is a problem with the electrical impulses that control your heart, a narrow aortic valve, problems with the sinus node, which is the area of your heart that helps it to beat, or various other problems with your heart's structure.  

Now one thing that I didn't mention, about the last paragraph is that a blood clot depending upon where it is can result in a stroke.  This can also be a reason for a fainting spell as well.  

Credit: www.drsinatra.com

After doing a little research on the subject I found out that people fainting and hurting themselves during the fall is the reason for 3% of all emergency room visits, and 6% of all hospital visits.  Talk about a scary number, and not a statistic that any person would want to be a part of.  

For the most part I think I was lucky.  The doctor told me that what had happened was a case of dehydration mixed in with a very strong dip in my glucose levels.  Apparently, falling asleep without eating dinner and having a very light lunch that same day made my blood sugar drop enough that I ended up fainting.  That's something I'm just going to have to be careful about from here forward.



Apr 16, 2013 5:04pm
I have fainted each and every time blood has been drawn from the crook of my elbow ...except when I was pregnant. That probably explains why I avoid doctors.
I also fainted when my six month old baby got a blood test, and when he got a shot of Novocaine at the dentist's office !
My condition was characterized as a "vaso-vagal" process which affects 1 out of every 100 people on average. The body is affected by thoughts in the mind. With me, It's not the sight of blood; it's the sight of the needle or blade, and at times it's even been the sight of the tourniquet being placed.
Apr 16, 2013 8:28pm
I remember my doctor talking about this one. He said it was a rapid drop in blood pressure caused by mental stress. It's both amazing and scary how the brain can control every little function, don't you think?
Apr 16, 2013 10:07pm
Agree ~ especially when you consider that there's so much of it that we're not even using ! It makes sense that it should be a rapid drop in blood pressure, because I always 'saw white' before I fainted.
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  1. "Low Blood Pressure (Hypotension)." MedicineNet. 15/04/2013 <Web >
  2. Dennis O'Neil "Human Blood Components." anthro.palomar.edu. 15/04/2013 <Web >
  3. "Hyperventilation and Hypoventilation - Role of the lungs in maintaining pH balance in the body.." http://georgiahealth.edu/. 15/04/2013 <Web >
  4. Peter Stetson "Development Of A Syncope Screening Questionnaire For Use In The Emergency Department: A Prospective Study." 2 ND YEAR RESEARCH ELECTIVE RESIDENT’S JOURNAL. 2 (1997-1998): 145-149.

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