O2 Level in the blood and question related to the blood quiz from thursday

[Frackingawesome]

This is a good resource on liquid breathing in diving: Wikipedia: Liquid breathing, Diving

This was one of the many "promising innovations" in diving when the concept was introduced to the public in the 1960s. Problems getting people "back" (on gas) has been the major showstopper. Another very difficult problem in practice would be regulating core temperature due to the high conductivity of liquids. Water is about 25x as conductive as air, HeO2 is about 6x plus as conductive depending on the mix.

I think i also read some where there are major issues with effort of breathing... moving liquid is WAY more work then moving air. We have issues moving "thick" air at depths.

 

[broncobowsher]

I don't think I saw it listed here yet, but regardless of the amount of O2 in the tissues, the metabolism is a constant. That is what makes a rebreather have the same consumables regardless of depth. For the same workload depth does not change the amount of Oxygen consumed nor CO2 produced. Having more O2 in your body doesn't mean you are using more O2.

And 3ATM of pure O2, not a good thing in a dive. In a chamber with a properly trained attendant it's not that big of a deal. So you get some convultions, bounce off the walls. You are not in the water, not going to drown. You should feel like crap the next day but being bent will make you forget about being sore from the convultions. Maybe that bruise on your forehead where you banged the chamber wall will hurt enough to take your mind off being bent for a minute or so.

 

[Akimbo]

I think i also read some where there are major issues with effort of breathing... moving liquid is WAY more work then moving air. We have issues moving "thick" air at depths.

I always understood that mechanical circulation of the fluid was a "given" for the reason you cite -- especially when you consider pushing the fluid through the scubbiing and oxygenation circuit. Two-way audio with the diver would be impossible anyway so a few tubes in your throat wouldn't be the reason comms was compromised.

At least you wouldn't need a helium speech unscrambler.

 

[Searcaigh]

you might find this useful

 

[Storker]

you might find this useful

One of the things I found fascinating during my biochem course was learning that while hemoglobin has a very strong ability to bind O2, myoglobin has an even stronger binding. So, when a hemoglobin molecule intersects with a myoglobin molecule, the myoglobin just steals the O2 from the hemoglobin.

And because marine mammals have a lot of (iron-containing) myoglobin in their muscle cells, their meat tends to taste slightly metallic and has a very dark red color. Which turns almost black upon cooking.

 

[GJC]

Guys thank you so much for helping me understand this.



does this mean that as we dissolve more O2 in the blood the venous saturation is going to increase as well? i think someone else said that the metabolic rate at which we use o2 is not pressure dependent so we would use the same about no matter how much is there right?

Also as the o2 is used by the organs and is pulled out of the plasma and tin turn is replaces by the hemoglobin is this a gradient type reaction meaning as the plasma has 3ish% the hemoglobin is fine but when the plasma drops to 1.5% the o2 has a higher affinity for the plasma then the hemoglobin and disassociates? or is there some other process involved?

further more if it is a gradient (maybe not the right word) and we have 6% or 7% in the plasma at depth does not that the o2 will stay on the hemoglobin until that low point is reached?

Correct to your first 3 questions but I can't verify your percents, your percents are dependent on pressure, concentration of oxygen in breathing gas, amount of plasma (hydration) and amount of hemaglobin (varies between individuals).

The answer to your last question depends on the partial pressure of O2 in plasma getting low enough to cause the chemical bond of hemoglobin to oxygen to release.

You can use this equation to figure out how much oxygen is in blood at various pressures

Oxygen Content

 

[dmaziuk]

One of the things I found fascinating during my biochem course was learning that while hemoglobin has a very strong ability to bind O2, myoglobin has an even stronger binding. So, when a hemoglobin molecule intersects with a myoglobin molecule, the myoglobin just steals the O2 from the hemoglobin.

And according to @rsingler myoglobin doesn't actually care who it steals its oxygen from, so at high enough concentrations of dissolved O2, it just grabs that and doesn't bother with hemoglobin at all.

 

[GJC]

And according to @rsingler myoglobin doesn't actually care who it steals its oxygen from, so at high enough concentrations of dissolved O2, it just grabs that and doesn't bother with hemoglobin at all.

Myoglobin actually gets all it's O2 from plasma as there is no direct path from the hemoglobin within the red blood cells to get to myoglobin within the muscle cells without having to first pass through plasma. As O2 in plasma drops, hemoglobin releases O2 that moves into plasma.