What causes hypovolemia?

[lthomas521]

Hi fellow POTSers

Many of us (and many of the people with chronic fatigue syndrome) have low blood volume--a combination of low red cell mass and low plasma volume. If the reductions are in proportion to each other, the result is a normal hematocrit and normal hemoglobin readings. The blood itself looks normal, there's just not enough of it. So we can have pretty serious anemia even though the tests that are usually used to detect anemia give falsely normal results. It's no wonder that some of us are tired all of the time and have poor exercise tolerance and a racing heartbeat.

This poses some interesting questions:

1. What can cause this problem?

2. What (besides fludrocortisone (Florinef] or recombinant erythropoietin [Epogen or Procrit]) can be done to correct it? I'm worried that Florinef can have bad long-term effects on bone mass, and recombinant erythroipoietin also has some drawbacks.

3. Why do so few doctors understand that you can be anemic even if your hematocrit and hemoglobin level are normal? I have tried to explain to them that the plasma volume and red cell mass determinations are like a dipstick, telling you the amount of oil in your engine. You can't just take a sample of oil from your engine, announce that it is normal, and then conclude that you are not a quart low.

[MightyMouse]

Florinef is different from conventional steroids. Long term use is safe with regard to bone mass.

Increased fluid intake and salt intake is typically the first line of attack, along with sports beverages.

Nina

[lthomas521]

Florinef is primarily a mineralocorticoid, as opposed to cortisone, which is primarily a glucocorticoid. However, the prescribing information for Florinef does mention that all corticosteroids increase calcium excretion and it lists osteoporosis under adverse events. I looked up bone density and fludrocortisone in MEDLINE and found nothing except two articles about people with congenital adrenal hyperplasia, which may be irrelevant. I have seen no data about bone mass in people who have received long-term treatment with Florinef for POTS, or about people who have used salt loading to manage POTS.

Increased fluid and salt intake are typically the first line of attack. However, if that were sufficient, none of us would still be sick. Extra saltwater doesn't stay in your bloodstream very long unless you have kidney problems.

So why are so many of us anemic?

[Ernie]

Hi lthomas521,

Welcome to the board,

Do you have any opinion as to why we are anemic?

Ernie

[janineerrn]

I have been doing a lot of research on low blood volume. I am a Registered Nurse and cant stand the fact that my peers (doctors) have no answers for me.

There are many mechanisms in our bodies that regulate blood volume and blood pressure. Example: You stand up, hundreds of things happen for our body to adjust to that movement. It starts in the brain, every nerve impule is transmitted by a chemical (neurotransmitter). These nerve impules trigger other chemicals released by the thalmus(for one) that controls blood pressure, the kidneys secrete chemicals that control blood pressure and volume. The response in the elasticity of your blood vessels secrete chemicals that regulate blood volume and pressure.

Anything can go wrong during any of these processess to make you sick. Its a giant cascade.

Ummmm, I better keep this short.

Basically I think that those of us with low blood volume have something that has to do with thalmic regulation. It is sending out signals that we have normal blood volume when we dont. If I only knew why...........

This condition is driving me nuts, I am sooooooooo tired.

Janine

[Ernie]

Hi Janine,

Thanks for the explanation.

I don't know for the other people but what I feel is the problem in my case is exactly what you explained. My body is sending a signal that I have normal blood volume when I don't and when I have normal blood volume (after I get an IV bag) it sends the message that I have too much blood.

I would also like to know the origin of this problem, ie thalamus or kidney, etc..

I understand your frustration at not having answers. I would also like to know the etiology and proper treatment for this condition. I think I will spend the rest of my life to search for answers.

I believe that many doctors are blind folded and only go by what they learned in med school. We should have more researchers helping us. It is still a large field to investigate.

Ernie

[Jenn202]

Blood Volume issues are my biggest problem...if I could solve them I would be almost 100%.....

My Dr is doing a genetic test on me that supposedly shows whether I am missing a certain Gene that controls Fluid volume.....

I'll let you guys know how it goes...

Other than that I have no idea why so many Dr's cannot understand just b/c yoru Blood work shows you have balanced electrolites , that does not mean you have ENOUGH BLOOD in your system.....

Its funny how we all understand it.....

I hope that this area had more research devoted to it......

[MightyMouse]

I can tell you that I'm not anemic. My hematocrit is lovely. My red cell mass is pretty good. I've have a low total volume as per nuclear med testing--mostly low plasma.

As I said, the research does NOT support your assertion that it deplete bone mass. Corticosteriods DO deplete bone calcium. As somone on long term asthma treatment, I can attest to that. I did wonderfully for many years on florinef, however, not everone is a "florinef responder" as per my doctor at NIH (David Goldstien).

You are probably not going to get the answer to your primary question as to what it is, exactly, that depletes volume. If that was understood, we would not all be here. Michelle has done a great job of linking what's presented on http://www.dinet.org with fully linked references. The medical system hasn't gotten that far yet.

Nina

[Gena]

Low aldosterone production due to malfunctioning adrenal glands/adrenal insufficiency can cause low blood volume as well. But the prescribed treatement for this is Florinef, which we all know doesn't work for everyone.

Wish some researcher could find the definitive answer to this!

Gena

[ramakentesh]

My doctor thinks that there could issues with the kidneys in regulating volume, but i guess if it was an easy thing to work out it would have been by now.

[Roselover]

I was told by a doc that I couldn't have low blood volume since my BP could get up to 120. (A general doc unfamiliar with Dysaytonomias)

Any comments?

Roselover

[lthomas521]

I suspect that there are several possible mechanisms. Unfortunately, the diagnosis of our type of anemia is generally missed. It's hard to get a physician to believe that you are anemic if your hematocrit and hemoglobin are normal. They dismiss rapid pulse as evidence of an anxiety disorder or at best as "just" an autonomic nervous system problem. Since the hypovolemia goes unrecognized, no one collects enough cases to do any real investigation.

A few months ago, the POTSplace newsletter ran something from Emma, who explained that she was getting supplemental albumin, and that it was doing her a great deal of good. I suspect that for many of us, POTS is related to a problem with albumin homeostasis. Emma said that for some people with POTS, the body just doesn't make enough albumin, or maybe it consumes it too rapidly. My theory is that the kidney's "critmeter" then adjusts the red blood cell mass to match the abnormally low plasma protein. Then, the adrenals work overtime to try to compensate. The result would be hyperadrenergic POTS.

An abnormality in albumin homeostasis could result from impaired production (e.g., from liver failure) or from increased consumption. My personal pet theory is that an impairment of gluconeogenesis (production of blood glucose from other forms of stored energy) could predispose a person to hypoglycemia, which then causes the body to burn plasma proteins for energy.

Different mechanisms would be responsible for other types of POTS. For example, someone may have normal blood volume but suffer from pooling of blood in the lower part of the body. This sort of thing would be more likely in a patient who has a primary neurologic disorder or who has had neurologic damage as a result of diabetes. The end result, thoracic hypovolemia, would be the same.

Anemia can result from a dietary deficiency, so I suppose that anyone with anemia should have their folate and vitamin B12 levels evaluated. If you have pernicious anemia, you won't be able to absorb B12 from an ordinary vitamin pill. You may need injections or an intranasal product. In general, it probably wouldn't hurt to take more than normal doses of B vitamins, but tell your doctor if you do. Also, there is a hereditary form of thiamine-responsive anemia--i.e., it gets better if you take abnormally high doses of thiamine. It's due to an abnormal thiamine transporter and can cause deafness and diabetes. Your thiamine levels could be completely normal.

People should ask their doctor before taking an iron supplement. It's conceivable that your problem could be due to hereditary iron overload disease (hemochromatosis), especially if you are a man or a postmenopausal woman, and especially if you are of Irish, Welsh, or Scottish descent. Iron is a highly reactive element and causes all sorts of damage in the body if there is too much of it. Extra iron might be particularly bad if you have a mitochondrial problem, which I suspect many of us might have. The extra oxidative load will cause further damage to the already malfunctioning mitochondria. If you do take an iron supplement, please make sure to keep it out of the reach of children. Iron supplements are a major cause of fatal poisoning in children.

As for whether you can have a systolic pressure of over 120 mm Hg if you are hypovolemic--yes, you can.

[lthomas521]

Here's a description of a man with very low blood volume but hypertension:

http://www.pediatricnetwork.org/medical/CF...ry/oi-intro.htm

[Ernie]

Hi lthomas521,

I like your theory about "An abnormality in albumin homeostasis could result from impaired production (e.g., from liver failure) or from increased consumption. My personal pet theory is that an impairment of gluconeogenesis (production of blood glucose from other forms of stored energy) could predispose a person to hypoglycemia, which then causes the body to burn plasma proteins for energy. "

I have hypoglycemia and when I eat more protein I feel much better (less presyncopal).

I will try the albumin and see if it helps.

I have low blood volume (low red blood cell and low plasma) and I my BP can go from 210/140 to 25/25 in less than 5 minutes.

Ernie

[Merrill]

lthomas521--are you a doctor?

Just curious...

[Jenn202]

I have low blood volume and hypertention...People with ANS problems can have BP all overt the boerad..not just low BP..mine is actually high most of the time...

[lthomas521]

lthomas521--are you a doctor?

Just curious...

<{POST_SNAPBACK}>

No. Just a technical writer with access to a medical library.

[ramakentesh]

'I suspect that for many of us, POTS is related to a problem with albumin homeostasis. Emma said that for some people with POTS, the body just doesn't make enough albumin, or maybe it consumes it too rapidly. My theory is that the kidney's "critmeter" then adjusts the red blood cell mass to match the abnormally low plasma protein. Then, the adrenals work overtime to try to compensate. The result would be hyperadrenergic POTS. '

If that were the case it should be quite easy to demonstrate this.

I think you might be on the right track, but if you use me as an example there could be problems as well.

Firstly, my BP rises when i stand and I have hyperadrenegenic POTS. My albumin levels are actually high normal rather than low, although my overall blood volume is low. I guess if this were the case, the increase albumin could only be considered in reference to my current blood volume and could still be quite low when compared to a normal person.

Many people with POTS have a type of hypoglycemia problem, but from my understanding the vast majority of POTS patients can pass a glucose tolerance test despite getting an adrenegic reaction to going without food in the morning or after high glucose consumption.

My guess is that POTS is related to complicated migraine activity, since it can be triggered by similar foods to migraine triggers - but even then i dont feel that this theory adequately covers many of the symptoms so its just a guess.

Good luck with your theories anyway - hope you find the answer - i for one would be VERY happy!

[sue1234]

I found this old thread, and thinking that here we are, 6 years later, and STILL wondering about all these things!!

I have to admit, though, that I really like 'lthomas521' theory on the albumin and blood glucose. I know hypoglycemia has always been a pre-existing issue for me. I don't really understand what he said, exactly, but I'll read up on it. What I get is that having low blood sugar(chronic) could use up available albumin or protein. So, even though your labs show you have great levels of albumin, maybe they are being diverted to glucose homeostasis. That would leave the vascular system without the albumin to pull water into it. Then, we would be "leakers" of fluid.

I don't know, it sure sounds plausible to me.