Collecting C02 Samples at depth.

[Zebra 1]

Is there any standard or program in place for collecting air samples at depth for later analyzation? I would like to know what the CO2 levels are and maybe determine if I am a "CO2 Retainer".

 

[davehicks]

Maybe manually fill your DSMB with the oral inflator at your target depth?

 

[Zebra 1]

I was thinking maybe some type of balloon and collecting samples under different conditions, heavy workload, deep, cold, etc.

 

[rjack321]

You need a chamber, co2 retention is measured in blood gases not via your exhalation. Unless you want to dive with an IV in your arm.

 

[Zebra 1]

Interesting, I just assumed that the exhaled gas should have high C02 levels when blood levels are high. I thought that reduced respiration rate is what leads to high blood C02.

 

[rjack321]

Interesting, I just assumed that the exhaled gas should have high C02 levels when blood levels are high. I thought that reduced respiration rate is what leads to high blood C02.

Hypercapnia and CO2 retention is defined in as the ppCO2 in arterial blood. There is some relationship with end tidal CO2, but its going to be highly dependent on workload. Without a standard workload, the end tidal Co2 isnt relevant to anything.
You can see the relationship here in Figure 1
Hypercapnia in diving: a review of CO₂ retention in submersed exercise at depth. (duke.edu)

Only 1 measurement isnt clinically relevant anyway.

 

[rddvet]

I was thinking maybe some type of balloon and collecting samples under different conditions, heavy workload, deep, cold, etc.

balloons are porous so not ideal.
But as rack said, there’s not really a point to this exercise because CO2 in your blood is what you’re after. Expired CO2 won’t be the same or directly correlate. Also, how would you get it measured?

 

[Zebra 1]

Got it, thank you and thank you for the link.