Low blood volume and high blood pressure

[Sarah Tee]

I suddenly thought how is it possible that I have low blood volume and high blood pressure.

My specialist thinks I have low blood volume, and there’s indirect evidence as well. And that’s been going on for about 20 years. BP was normal in those times.

But for the last five years, I’ve had high BP.

Is that even possible with low blood volume? Or is my blood pressure actually even higher and some of that is being disguised by the low blood volume?

[MikeO]

not sure if this helps you.

The cardiovascular system combats low blood volume by constricting blood vessels until the body reaches a blood pressure that restores proper perfusion pressure.

[MomtoGiuliana]

When I am in a flare up my blood pressure on standing increases along with hr, and my blood volume is low--I benefit from salt and extra fluids--that brings my bp down.  Crazily, I will also feel dizzy even tho my bp is high (not dangerously high --generally no higher than 150/90).

[Sarah Tee]

@MikeO, @MomtoGiuliana, thank you, that makes sense!

I was just having a sudden crisis about this because I’m starting with a new GP.

I really wish I had measured my blood pressure before and after having IV albumin. They took my obs at the hospital, but my blood pressure was always high because getting there and being there was a big hassle (even though the staff were very good).

In the old days, my OI symptoms would go away later in the day, so I could have measured it then too. (It lasts pretty much all day now.)

And I could have checked it when I was on prednisolone and feeling normal too. Argh. Although prednisolone can raise your BP.

So many missed opportunities to see if it goes down when I’m revolumised or asymptomatic.

Regardless, am going to ask new GP to test me for Conn’s syndrome. Apparently it’s quite common and my high BP may not be from dysautonomia (it started about ten years in).