jangle Posted January 7, 2012 Report Share Posted January 7, 2012 I was reading this study:http://jap.physiology.org/content/99/3/828.fullWhich basically says that our cerebral blood flow is the same as people without POTS. There have been studies which contradict this study, but this study seems very rigorous (included 27 patients with POTS) and honestly the other studies show a difference of about ~9% blood flow between control subjects and POTS which I don't know is statistically significant.If one accepts this study as being representative of what's occurring in people with POTS, then what's producing our symptoms of pre-syncope?Could it be that our heart rates are so high that blood isn't given enough time to exchange oxygen and CO2 in the alveoli of the lung which would produce a lower oxygen level? This doesn't really make sense because SP02 (Oxygen saturations) are normal in POTS patients. But then SP02 can also be normal in anemic patients despite having clinical symptoms.I guess I was just wondering what other people's opinions are, do you think this study I linked is accurate or do you think our cerebral perfusion is lower than people without POTS? Quote Link to comment Share on other sites More sharing options...
lieze Posted January 7, 2012 Report Share Posted January 7, 2012 Well our SPO2's are not always normal.And blood gasses definitely aren't after exertion.It could be a hypersensitivity like everything else.We may be getting blood flow but our bodies do not recognize it and therefore send out messages and start initiating maneuvers that are not necessary only perceived by a faulty system.Also I think that I've read that during anxiety attacks there is a displacement of O2 to CO2 due to some of the chemicals released into the bloodstream which causes some of the symptoms of lightheadedness and disorientation.Our bodies just seem to struggle to maintain balance and seem to have a tendency to go into crisis mode when there maybe isn't a reason to be in that mode in the first place. Quote Link to comment Share on other sites More sharing options...
Katybug Posted January 7, 2012 Report Share Posted January 7, 2012 Well, about 5 minutes after eating dinner this evening, my mother looked at me and said you should go lay down. I said yes I feel awful (typical after dinner routine, really). My blood pools badly in my lower GI tract after I eat, no matter what I eat and its always worse in the evening. But, my mother knows when it happens because the blood drains out of my face and I become pale (the color people look in their casket, gray and pasty.) My stomach becomes so bloated with blood that I look pregnant and my legs change color to somewhere between red and purple (some of the blood goes to my legs). Then the typical POTS symptoms kick in. SO, I have no scientific proof but my body definitely tells a story of significant cerebral profusion. Quote Link to comment Share on other sites More sharing options...
ramakentesh Posted January 7, 2012 Report Share Posted January 7, 2012 I know from when I got diagnosed that posturally there was a large reduction in carotid artery blood flow - so at least for me I can be certain that I have cerebral hypoperfusion. While that study may suggest one thing, the vast majority of research indicates that there is a reduction in cerebral hypoperfusion on standing in POTS. Stewart and Medows were recently wondering why the effects of postural stress were so apparnt in patients with minimal cerebral hypoperfusion and there seemed to be some indication of an over sensitisation to hypoxia. Quote Link to comment Share on other sites More sharing options...
lieze Posted January 7, 2012 Report Share Posted January 7, 2012 Katy I'm a slow learner but I just realized about a week ago that I was reacting to the temperature of my food.I have to wait until it cools down to room temp and then eat or I really suffer.I'm not sure if this is an issue for you or not or would help but I thought I would mention it. Quote Link to comment Share on other sites More sharing options...
ramakentesh Posted January 7, 2012 Report Share Posted January 7, 2012 A doctor once told me to drink everything cold - hot = vasodilation, cold = vasoconstriction Quote Link to comment Share on other sites More sharing options...
Katybug Posted January 7, 2012 Report Share Posted January 7, 2012 Yes, I have to eat and drink everything at room temp. Except when I feel really hot or cold (body temp)...then I can actually use food and drink to change my body temp. It would be kind of cool if it wasn't from being sick all the time. Quote Link to comment Share on other sites More sharing options...
ramakentesh Posted January 7, 2012 Report Share Posted January 7, 2012 In a study of nine patients with POTS, the α-adrenergic blocker phenotolamine, volume replacement with isotonic saline, or infusion of phenylephrine all acted to reverse the significant CBV reduction during orthostatic stress (28). These data suggest that, in this subgroup of patients with POTS, cerebral hypoperfusion might be due to exaggerated sympathetically mediated cerebral vasoconstriction (8, 53).From that study. Quote Link to comment Share on other sites More sharing options...
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