Does Cpap change blood/oxygen relationship

[puffin]

Just a quick question about how an increased oxygen supply effects the amount of red blood cells the body produces?

Basicaly I am a regular blood donor (50 donations so far). The blood transfusion service does not take blood if the red cells are low. My last two attempts to donate failed because of just being below the required levels. These last two attempts where after getting a cpap machine.

I've been told that I may be one of those people who naturaly have a low red cell count. But I was wondering, not knowing how this works, because I have mild SA (10 per hour) would my red count rise to compensate for lack of O2. Now I get more O2 would my red drop to my natural level and below the NBS level?

Any ideas please?

[Joe McManus]

This is all 'thinking-out-loud' for now, I'll read into it a bit more later, but here's one way to look at it.

Before CPAP you had low blood oxygen saturation. Red blood cells are responsible for carrying this oxygen around. The lack of oxygen due to OSA may have prompted the body to produce more red blood cells as a panic-reaction, in a bid to make sure every bot of oxygen is being transported and used.

Fast forward to post-CPAP, you have fewer Apnea events hence rising oxygen saturation levels. Less stress on the body may prompt the body to not need that many red blood cells as there's plenty of oxygen to go by.

I was quickly reading how red blood cell production works via this PDF and some related Wikipedia articles. Some proteins required to trigger red cell growth originate in the kidneys (Erythropoietin - see Hematopoieses stating Erythropoietin is required for a myeloid progenitor cell to become an erythrocyte (that is a red blood cell.) I wonder whether besides CPAP you may be experiencing any other changes you may now necessarily readily notice. Ranging from under performing bowel to skin issues which may reflect kidney issues. The nutritionist I interviewed recently also mentioned how some people loose blood like through such as bowel disorders or haemorrhoids.

But again, there's a lot to it as can be seen by those linked Wikipedia articles so I'll have to dig a bit deeper to see whether what you experience could indeed be down to CPAP doing its thing. Definitely an interesting question to investigate!

[puffin]

Thank you for your reply. What got me thinking about the problem was a resent BBC TV programme "Horizon". A large group of Doctors, 60 plus, went to climb Everest, studying the effects of much reduced O2 sat. levels on the body.

They took their own blood as samples, from sea level right upto the summit. Even took an exercise bike upto the South Col, 8,000 metres to work out how the body reacts to reduced O2 levels and high Alt. stress. Intestingly they recorded sats. as low as 40%. They said if their patients had sats. this low they would be died!

The point I am making is that the higher they got the more red cells they had. Higher also means less O2 as the air gets thinner. Blood becomes much thicker and even changes colour to blue/purple as the body adjusts to lower O2 levels. If the blood becomes too thick, strokes happen plus other nasty things.

So you can see where I am coming from with my question. If you make a small change in air pressure, i.e. Cpap, would it be seen as a change in red cell count?

[puffin]

Just an extra thought. If air pressure at sea level is say 14psi. What difference would a cpap make to the psi if it set at 10, the setting of my machine. This would equal, how many metres below sea level?

An extra, extra thought. As we use cpaps for only a third of a day would it make any differance at all?

[Joe McManus]

Thank you for your reply. What got me thinking about the problem was a resent BBC TV programme "Horizon". A large group of Doctors, 60 plus, went to climb Everest, studying the effects of much reduced O2 sat. levels on the body.

I watched it too and couldn't help but link their reasoning to OSA as well. I blogged my thoughts about it here: http://blog.cpap.co.uk/2007/10/sleep...-mount-everest

The point I am making is that the higher they got the more red cells they had. Higher also means less O2 as the air gets thinner. Blood becomes much thicker and even changes colour to blue/purple as the body adjusts to lower O2 levels. If the blood becomes too thick, strokes happen plus other nasty things.

I didn't remember them mentioning blood cell counts, must have missed that bit but I Googled the study they did so I'll have a read of their written findings to better understand it all.

So you can see where I am coming from with my question. If you make a small change in air pressure, i.e. Cpap, would it be seen as a change in red cell count?

Do they normally count it as a percentage or in absolute numbers? If more oxygen is in the blood then obviously the number of red blood cells/molecules will be relatively lower even though the exact count remains the same.

[JackTheSnorer]

Interesting discussion!

This study researched the effect of stress on blood cell parameters:

http://www.ayubmed.edu.pk/JAMC/PAST/14-1/Faiyaz.htm

One of the conclusions was an increase in RBC.

Pre-CPAP your body would have been under a lot more stress compared to post-treatment. That could indeed mean your suspicion of always having been low RBC could be true.

[puffin]

Interesting study, I won't pretend to understand everything in it. The way I understand it, stress can cause changes in blood cemistery.

If living and working in a stressful enverament (since 2000 I been made redundant 4 times before starting my own business 18 months ago.) Mixed with OSA could have raised my red cell count as a response.

Now that I am working for myself I am under a great deal less stress from others. This, combined with cpap treatment, further reducing unseen body stress. Could have been reflected in a small drop in Red Cell count.

Interesting!

[JackTheSnorer]

This, combined with cpap treatment, further reducing unseen body stress. Could have been reflected in a small drop in Red Cell count.

This 'unseen' stress is often forgotten or overlooked, I get the impression. Any body not 100% healthy (all of us including non-OSA people nowadays) are under some degree of physical stress as the body tries to cope. All the pollution, western diet, general sleep deprivation; it can only cope so long.

Knock back 2 cans of Red Bull and you feel first hand what this physical stress is. Heart is pounding!

Someone in an un-stressful, relaxed environment is not necesserily stress-free physically and/or mentally. Doing nothing (redundant) when wanting to do something can be stressful too.

[puffin]

Just an update on this thread. Saw Consultant at the Hospital today (09/01/08), as it appears that there is a problem somewhere. Low ferrites (sp?). Normally only seen in the ladies, regular blood loss. However there could be a number of other causes that have to be checked first. Meaning yet more blood tests, and now cameras "Up and Down" Hope fully not the same camera.

[DozyDaisy]

Good Luck Puffin

Hello Puffin. I have been MIA due to illness. This is just to say "Good Luck" for your forthcoming tests. Hope all goes well.

Happy 2008

Daisy


QUOTE=puffin;1415]Just an update on this thread. Saw Consultant at the Hospital today (09/01/08), as it appears that there is a problem somewhere. Low ferrites (sp?). Normally only seen in the ladies, regular blood loss. However there could be a number of other causes that have to be checked first. Meaning yet more blood tests, and now cameras "Up and Down" Hope fully not the same camera.[/QUOTE]

[puffin]

I'm just waiting for Pickle-lax (sp) pack and test date from the hospital. Suggestion is wheat allergy, celiac disease, preventing mineral uptake in the gut. http://www.nhsdirect.nhs.uk/articles...?articleId=105

Thanks Daisy