Today I want to talk about a poorly condition called POTS which causes a lot of young patients (children and women mainly between the ages of 14-45) a lot of debilitating symptoms and distress and because POTS is a relatively newly recognised condition, many doctors don’t know very much about it and attribute symptoms to anxiety or psychological issues and therefore the poor patient’s distress is compounded by having to find a doctor and support system that takes their symptoms seriously.
Basically what happens in POTS is that the patient develops Orthostatic intolerance which means that they don’t tolerate standing up for any prolonged period very well and therefore have to sit down and the reason for this is that their heart speeds up excessively when they stand up and that feels very uncomfortable and they get palpitations, dizziness, sometimes headache and feel worn out.
POTS is thought to be a disturbance of the autonomic nervous system which s that part of our nervous system that regulates body functions such as our heart rate, respiratory rate, pupillary response, digestion and urination. The way the autonomic nervous system works is by 2 contrasting systems. The parasympathetic system controls our body processes during ordinary situations and the sympathetic system which prepares our bodies for stressful situations. So for example, if we are suddenly scared, the sympathetic system is activated and immediately our heart rate goes up, we start breathing harder, our pupils dilate and blood starts going to our muscles rather than our gut and therefore any digestion slows down and we recognise this as an ‘adrenaline rush’ .
However after the initial stressor has been taken away, slowly our body slowly returns back to normal and this is done via the parasympathetic system and the autonomic system comes back to achieve an equilibrium.
An analogy I think which may help explain what happens in POTs is that of a see-saw with the pivot point in the middle. A stressor is like pressing down on one side of the see-saw and this activates the sympathetic system which causes all these changes within the body to prepare you for flight or fright.
Now what happens in POTS is that the pivot has been moved so only a small stressor causes an exaggerated rise in sympathetic activation and therefore the patient notices this florid flight or fight response which feels really strange and uncomfortable because it is happening when the patient is not really doing anything to trigger such a reaction. SO let’s see what happens when we stand up from a lying position.
As we stand up gravity starts taking effect and therefore because our blood vessels are stretchy, Immediately blood starts getting sucked down by gravity and if nothing were to happen then our brain which is the furthest away from ground will be drained of blood and we would collapse.