C02 Blood levels increasing

[SleepyDeb]

Hi All...just had a physical and blood tests show C02 flagged as high - 33. I looked over the past two tests also taken in 2017 and see that it has been gradually increasing. I wonder if it is my CPAP therapy doing this. When I was tested for sleep apnea a couple of years ago the 'script called for a low pressure level of 8 and high at 15. I found very quickly that it was way too high for me and that the nose mask didn't work because I'm a mouth breather during REM (my test showed I hardly reached REM)...I switched to a full face mask and started lowering the range bit by bit. At this time I'm at 7.8 low and 8 high (I know, not much difference but I like the little bump up once I fall asleep). My AHIs have been under 3...usually under 2...for over a year...but...I'm not feeling fully well - still a bit tired and sometimes light headed but not nearly as before therapy...I still get air in my stomach even at low pressure levels but not nearly like it was at the high levels (nothing helps me with air...tried all the recommended advice). I do have a thyroid condition but the meds have it in the normal range; I do have scoliosis that presses into my lung so I've always not breathed well all my adult life... But now when I see the carbon dioxide increasing in my blood it concerns me. The doc says don't worry in capital letters because it's only 1 point over. What are your thoughts?

[Julie]

I'll presume you're not consciously or otherwise covering the CO2 vent on your mask when asleep which would cause you to rebreathe CO2, so I'll also assume the MD's correct when he says not to worry about that small amount.

[Guest]

Hi All...just had a physical and blood tests show C02 flagged as high - 33. I looked over the past two tests also taken in 2017 and see that it has been gradually increasing. I wonder if it is my CPAP therapy doing this. When I was tested for sleep apnea a couple of years ago the 'script called for a low pressure level of 8 and high at 15. I found very quickly that it was way too high for me and that the nose mask didn't work because I'm a mouth breather during REM (my test showed I hardly reached REM)...I switched to a full face mask and started lowering the range bit by bit. At this time I'm at 7.8 low and 8 high (I know, not much difference but I like the little bump up once I fall asleep). My AHIs have been under 3...usually under 2...for over a year...but...I'm not feeling fully well - still a bit tired and sometimes light headed but not nearly as before therapy...I still get air in my stomach even at low pressure levels but not nearly like it was at the high levels (nothing helps me with air...tried all the recommended advice). I do have a thyroid condition but the meds have it in the normal range; I do have scoliosis that presses into my lung so I've always not breathed well all my adult life... But now when I see the carbon dioxide increasing in my blood it concerns me. The doc says don't worry in capital letters because it's only 1 point over. What are your thoughts?

Are you taking any antacid tablets? They can increase your blood CO2.
Otherwise, look up some of the resources about the tests and what they show and what can affect them. Like this:


Results
A carbon dioxide (bicarbonate) test measures the level of bicarbonate in the blood.
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Results are usually available in 1 to 2 days.
Carbon dioxide (bicarbonate)1
Normal: 23–30 mEq/L (23–30 mmol/L)

High values
High carbon dioxide (bicarbonate) levels may be caused by:
Vomiting, dehydration, blood transfusions, and overuse of medicines that contain bicarbonate (especially antacids).
Conditions such as anorexia, chronic obstructive pulmonary disease (COPD), fluid in the lungs (pulmonary edema), heart disease, Cushing's disease, and Conn's syndrome.

Low values
Low carbon dioxide (bicarbonate) levels may be caused by:
Hyperventilation, aspirin or alcohol overdose, diarrhea, dehydration, and severe malnutrition.
Liver or kidney disease, a massive heart attack, hyperthyroidism, or uncontrolled diabetes.

What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include the following:
You drink liquids that are very acidic, such as orange juice or some types of carbonated beverages, shortly before having the test.
You are taking some medicines, such as diuretics, some antibiotics, glaucoma medicine, and corticosteroids.
The health professional leaves on the elastic band that stops blood flow for an extended amount of time before the blood sample is collected.

[ajack]

There are a few reasons and it's not silly high numbers.
If it has anything to do with your breathing...can you get a sleepyhead chart up. and see with your tidal volume, minute vent and breath per minute is. They all may be ok and the cpap is the answer and a tweak of settings may be enough, or you may need to move to a BPAP

[archangle]

I don't think CPAP or sleep apnea is likely to be related to your CO2 numbers, unless they're doing the blood draw in your sleep.

I think that CO2 concentration in the blood has a very short half-life. Sleep apnea or rebreathing your exhaled air could increase your blood CO2 while asleep or wearing the CPAP mask, but once you wake up, remove the mask and start breathing normally, your blood CO2 will be back to "normal" within a minute or two of normal breathing. The same would be true for O2. In this case, by "normal" I mean the CO2/O2 concentration you would have had without CPAP or Apnea.

The cause is likely some of the conditions listed in the post above. There's also a hypoventilation condition that can cause it because you simply don't breathe enough when awake.