Breathing poisonous gas

[Timberman]

I have been reading about DLCO which is not a test I have had. But I was astonished to read that it involves breathing carbon monoxide. This is a highly poisonou gas which humans do NOT breath normally. It says it is used as a surrogate for oxygen. Now I am no scientist but the exchange function of our lungs which takes place in the alveoli will be dependent I feel sure on the surface of the millions of alveoli being able to pass oxygen into the blood stream (one way only) and uptake waste gases especially carbon dioxide and nitrogen from the blood stream (again, one way only).

I believe I am right in saying that since all molecules have different shapes this is done by shape differentiation in the pores of the alveoli surface. COPD, in whatever form, results in the deformation of these alveoli such that this process is inhibited to varying degrees.

I have read that each alveoli might only in fact pass one molecuyle in each direction and that our respiration depends on the vast number of such transactons. In a healthy body there is some 100% redundancy built in. Which is why we COPD sufferers get into trouble once we are below 50% transfer.

But this is about oxygen one way and carbon dioxide and nitrogen the other. NOT carbon monoxide surely?

SO here is my question - What value is the test in reality and how do we avoid being poisoned?

For the record this is CO: Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. It is toxic to hemoglobic animals (both invertebrate and vertebrate, including humans) when encountered in concentrations above about 35 ppm, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere, it is spatially variable and short lived, having a role in the formation of ground-level ozone.

AND PS: My symptoms are aggravated by ozone which often occurs at low level near the sea and is a feature of urban pollution.

PPS: I may have had this test using a cabinet device.

[Hidden]

Don’t worry, it’s a very tiny part of the test. If I remember properly( I have done so many tests over 60 years) it is to do one measurement of gas exchange. It seems to be breathe in, hold it, the machine whizzes and you breathe out. These testing procedures are so rigorously controlled that I am sure there is no danger of us being poisoned.

[Timberman in reply to Hidden]

Oh I am not worried but I am curious as to value and methodology. I now realise I did it in a cabinet where the incoming air is cut off suddenly and then restored.They measure differentials I assume. Quite unpleasant but no one mentioned that it was CO I was breathing. Had they I would have declined. I was a hack so I have seen a few CO suicides and attended a few inquests.

[Hidden in reply to Timberman]

I think they use a great deal more CO to commit suicide. I have bronch so don’t go into a cabinet. My tests are different to copd. I hope that you are ok after all of that. For some reason your reply went into my junk box. Teqnology!

[Timberman in reply to Hidden]

35 parts per million enough to do it....

[Hidden in reply to Timberman]

So nobody survived such a test then?

[Timberman in reply to Hidden]

No idea - presume the concentration is lower but that is why I posed the issue. Maybe we shall find out more. Tx for the interest.