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Date of last update: 10/20/2017.

Forum Name: Miscellaneous Cardiology Topics

Question: Episodes of passing out & Night Sweats

 sm0ke14 - Tue Jan 13, 2009 1:23 am

Hi, my name is Joe. About six months ago I went to the doctor about sweating at night an frequent trips to the restroom to urinate. He done CBC and found nothing alarming, so I ignored it. The frequent urination never happened during the night and has since stopped. So I think it might not have anything to do with my condition. I still experience night sweats about 3 to 5 time a week. Now on to the passing out episode I recently had. I was getting out of bed first thing in the morning when I suddenly fainted in the hallway. I must have woke right up because by the time my girlfriend heard me fall I was awake and alert. I remember everything that happened. Then just a few minutes later I passed out in the kitchen for a minute or two. Once I woke from this episode I felt normal. I went to the hospital and they ran all kinds of tests, such as a CT scan, MRI, EKG, Echo cardiogram, Tilt Table Test, and Stress Test. They diagnosed me with vasovagal syncope, due to postural hypotension. Which is sudden low blood pressure when standing up. They never said if the night sweats are a symptom of this diagnosis or not. I have tried to research some causes of night sweats and passing out together. The one thing I found is POTS (Postural Orthostatic Tachycardia Syndrome). POTS is a autonomic disorder that has to do with rapid heart rate while standing up and low blood pressure while standing up. The doctor never told me about this I found it on my own. I have had many CBC over the past few weeks and nothing alarming has showed up. If anyone can think of what is causing my night sweats and passing out, or if you have experienced the same thing I would greatly appreciate your help.

 John Kenyon, CNA - Wed Jan 14, 2009 10:19 pm

User avatar Hello -

You've done pretty much all the leg work on this already! POTS and vasovagal syncompe (now often referred to as neurocardiogenic syncope, although I feel "vasovagal" is easier to pronounce). I think the diagnosis is probably accurate as the workup was very thorough. The only remaining question regards the night sweats, and I may have a workable theory for that, even though it is usually seen in systemic infectious illnesses such as mono and tuberculosis. However, in your case I think what may have been happening was that you were having vasovagal episodes in bed, where you couldn't actually pass out because you were horizontal; very often these episodes, which usually take place while vertical, are accompanied by breaking a sweat suddenly. You may have had the "herald" symptom during your sleep and so didn't realize what was happening. Now you've had a couple of more normal episodes and know what you need to look out for in order to keep from being injured because of an unexpected fall. You aren't likely to hurt yourself if this happens in bed, because you're already horizontal. Since you're sleeping you probably wouldn't know it happened anyway. It is unusual, but there are things that can stimulate this, and one is nocturnal micturition (urination -- often with the patient passing out while standing at the toilet). So I suspect this is why you were having the night sweats.

I don't know that you have POTS, but it is usually related to orthostatic hypotension and vasovagal syncope when it occurs.

I hope this is helpful to you. You seem to already have all the really important issues in hand. Good work. Please follow up with us as needed.

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