High red blood cell count due to diving

[ScubaMarc]

Can high red blood cell count be due to diving?

A few months ago my doctor asked me to take blood work for some arthritis test. Which I did and it came back with a high red blood count. The doc told me to wait a month and take the test again. The result we a high normal blood count, better but still high. Again the doc to me to take the test again in 3 months, which is next month.

The doc told me do not be concerned about it. The most likely reason he sees is my diving activity. Low and high altitudes actives can cause the count to be higher than normal. I dive around 40 dives a year, which I do not see excessive enough to cause this, but I do not know enough.

Any thoughts???

 

[TSandM]

Boy, I have a hard time envisioning how diving could cause a chronically high RBC count. The biggest drive for increased RBC production is hypoxemia, which is why people who live at altitude have higher counts, as do people with chronic lung disease. But when you dive, your pO2 doesn't go down -- it goes up! Even people diving hypoxic mixtures for technical dives keep the actual blood pO2 at or above normal.

The immersion diuresis of a given dive (or series of dives) could result in a higher hematocrit (percentage of the blood which is cells) due to volume loss and concentration, but that would resolve with rehydration.

Maybe I'm missing something, but this one doesn't make sense to me.

 

[archman]

You're evolving into a pinniped.

 

[KazooDiver]

a High Redblood cell count (hematocrit) could result from hypoxia related to cronic high altitude, hypoxia in general, dehydration, and a couple of other conditions including a tumor. I don't know of a reason other dehyration or chronic hypoxia that could result from diving, and simple blood tests could further clarify the cause.

 

[MoonWrasse]

Boy, I have a hard time envisioning how diving could cause a chronically high RBC count. The biggest drive for increased RBC production is hypoxemia, which is why people who live at altitude have higher counts, as do people with chronic lung disease. But when you dive, your pO2 doesn't go down -- it goes up! Even people diving hypoxic mixtures for technical dives keep the actual blood pO2 at or above normal.

The immersion diuresis of a given dive (or series of dives) could result in a higher hematocrit (percentage of the blood which is cells) due to volume loss and concentration, but that would resolve with rehydration.

Maybe I'm missing something, but this one doesn't make sense to me.

Here's a tangentital question - I live at sea level, however I also have a home at 8000 feet above sea level, where I do a variety of activities (such as mountain biking).
I know one aclimates, but how quickly does the red blood cell increase/decrease occur?
Days? Weeks? Months?

 

[DocVikingo]

Hi MoonWrasse,

What initially happens is erythropoietin (EPO; a hormone secreted by the kidney that increases RBC production) level rises over the first ~2-3 days at altitude. RBC mass then increases about ~7-14 days after that. Of course when one returns to their customary altitude this reverses and RBC count goes back to baseline in a month or two.

In short, don't expect weekends training at a mountain retreat to result in meaningful changes in the oxygen carrying capacity of the blood.

Helpful?

Regards,

DocVikingo

 

[garyfotodiver]

I also have a high blood count (HCT >51%). Had it for years. There is a certain percentage of the population who do not fit into the "normal" ranges. The ranges are mere statistical analyses of small population groups.

In the absence of other disease or symptoms, don't worry about it.

 

[DocVikingo]

As a "quality assurance auditor" have you the medical background and medical facts required to make the statement, "In the absence of other disease or symptoms, don't worry about it?"

An abnormally high red blood cell count can lead to clot formation with subsequent blockage of capillaries, cardiac attack and stoke.

With a number of disoders, an elevated RCC may be the first and only indication that something is amiss and by the time other signs and symptoms appear damage has already taken place.

For example, polycythemia vera, an uncommon but potentially serious condition in which bone marrow produces an excessive number of RBCs, the disease typically develops slowly and there may be no symptoms for years.

Regards,

DocVikingo

 

[Brian1968]

Some of my patients at work (a sleep lab) are there for investigation of polycythemia. Sleep apnea can be a cause. While they are usually not hypoxic when awake they can become (sometimes profoundly) hypoxic for prolonged periods of time when asleep.

 

[ScubaMarc]

tumor

-AHHHHHHHHHHHHHHHHHH!!!!! I am going to die, but it will be extremly slow over 60 years.

I know one aclimates, but how quickly does the red blood cell increase/decrease occur?
Days? Weeks? Months?

The first high blood count would have been tested after a week of 10 dives, second test was after diving 2 or 4 times in the next month. SO I can see why the first test was high and the second was much lower. The third test might be high, becasue I had another week of 10 dives. Will know next month.

Doc said, it takes 3 months to regenerate all red blood cells in the body.

In short, don't expect weekends training at a mountain retreat to result in meaningful changes in the oxygen carrying capacity of the blood.

that is what I thought.

In the absence of other disease or symptoms, don't worry about it.

yep, but I will go along with some test just to make sure. I like being a pin cushion.