Gettysburg Medical News
 The Clinical View
 by P.E. Hoffsten, MD
 5 April 2006

THOSE FRIGHTENING FAINTING SPELLS

            The lady was 68 years old and brought to the emergency room on a Sunday afternoon because she had fainted at home.  It was her birthday and all five children plus sixteen grandchildren had gathered to celebrate.  She had received this surprise party with great joy.  There was a wonderful meal, a small glass of wine and good company.  A nine year old granddaughter then read a poem that she had written for the occasion.  Observers indicated that the patient was very moved, verging on tears.  The patient got up to excuse herself a moment to regain her composure.  She seemed to be unsteady for several steps and then simply collapsed.  She fell forward and family indicated that she did nothing to try to cushion her fall.  She was apparently unconscious while falling to the floor.  Fortunately, there was nothing in the way and she landed on a carpeted floor with no injury apparent.  As you might imagine, this kind of thing wrecks the party right away.

            Unfortunately, there was no one there that had any basic life support or emergency type training.  The family member’s response was to shake the lady to try to wake her up.  In a minute or two, the patient did begin to regain consciousness wondering what had happened.  Eventually, an ambulance was called and she was brought into the emergency room.

            In the emergency room, all of the tests that were done were normal.  It was suggested that the patient be hospitalized briefly for further evaluation and she just couldn’t understand why that was necessary if all the tests were normal.  There needed to be an explanation to the patient and to her very cantankerous eldest son.

            It was explained that fainting spells rarely represent a stroke.  There was no thought that the lady had had a stroke which was the family member’s thought initially.  It was explained that a patient faints for only two reasons.  Either the amount of blood going to the brain is not enough or the composition of the blood going to the brain is abnormal.  Her son said that seemed simple enough.  Which one was it?  I explained that the composition of the blood going to the brain can be abnormal for only two reasons.  Either there is too much of something that is bad or not enough of something that is good.  Most commonly, the not enough of something that is good is either not enough sugar or not enough oxygen.  But the patient’s blood sugar had been normal when she got the emergency room and there had been nothing done to supplement her blood sugar so we didn’t think she would have had a low blood sugar.  By the same token, she had not been unusually pale or blue prior to fainting.  So we didn’t really believe that there wasn’t enough oxygen in her blood.  So I explained to him that the quality of her blood based on the tests that we had appeared to be normal.  I didn’t think that not enough good things in her blood were the cause of her fainting spell.  By the same token, she had had only a small glass of wine.  She took no sedatives or sleeping pills.  She had no nerve pills or other products that might sedate her and make her likely to pass out.  It didn’t appear that there was too much of something bad in her blood.  Thus, I had told him that we had ruled out the likelihood of the composition of the blood getting to her brain was abnormal.

            At this point, her son was unimpressed.  He wasn’t really interested in what was not wrong.  He wanted to know what was wrong.  So I continued my explanation telling him that there were three causes for not enough blood getting to the brain.  First, the person may have had significant dehydration or bleeding in which the blood volume gets too low.  I explained to him that his mother’s blood count was normal.  The pulse and blood pressure were both normal now.  There was no reason to believe that she didn’t have enough blood.

            I next explained that a heart attack or the failure of the heart to work as a pump could result in not enough blood getting to her brain.  But his mother’s cardiogram was normal.  She did not have any chest pain either before or after the fainting spell.  Blood tests were done and there was no evidence that she had a heart attack so it appeared that her heart working as a pump was doing just fine.

            Finally, I came to the crux of the problem that I thought was probably present.  I explained that while the blood volume may be normal and the heart may be a really good pump, the clock that runs the heart might not be working right.  If the heart gets a message to beat too fast, it doesn’t have time to fill up with blood between heart beats and the person can faint just from that.  Alternatively, if the heart gets a message to beat too slowly, not enough blood is pumped and the person can faint from that.  Unfortunately, his mother’s pulse at the time of her fainting spell was not taken and we had no way to know which of these two explanations might be occurring.  I next told the son and the patient that a cause for the fainting spell is never found in about one-third of the patients who faint.  This definitely wasn’t reassuring to anybody.

            To make a long story short, I did talk her into staying in the hospital overnight for observation.  That evening at supper it was seen that her pulse had dropped to around 45 beats per minute which is abnormally slow (a normal pulse is 60 to 100 beats per minute).  She felt o.k. and didn’t pass out but this was a clue as to what had probably happened when she fainted.  Through the night when she was asleep, her pulse dropped into the low 40’s but caused her no symptoms that she was aware of.

            It was explained to her that someday in the future, she was probably going to need a pacemaker to keep her heartbeat fast enough to be safe.  She was counseled that certain medicines such as Digoxin, Verapamil, Diltiazem, Beta Blockers, or Amiodarone would all be drugs likely to make her faint in the future if they were ever started.  In addition, she was counseled that a slow heartbeat can result in substantial fatigue and could be another reason to have a pacemaker placed sometime in the future.  She badly wanted to go home and wasn’t at all interested in talking about pacemakers.  I suspect that someday she will return and need one.

            In summary, fainting workups are really pretty simple.  The first fork in the road is either not enough blood getting to the brain or something wrong with the blood going to the brain.  If there is something wrong with the blood going to the brain it is either too much of a bad thing or not enough of a good thing.  If there is not enough blood going to the brain, it is only because there is not enough blood, the pump isn’t working, or the pump isn’t getting instructions to pump correctly.  In spite of this very simple scheme on how to work up fainting spells, about one-third of the time we never find out what went wrong.  The healthcare providers at your local clinics are well aware of this simple algorithm.  They can help diagnose what might be wrong and then refer the person on when more complicated problems such as pacemakers, etc. might be needed.