Nitrox question

[scagrotto]

Oxygen transport by plasma is the key to hyperbaric oxygen therapy, for even poorly perfused tissue can receive oxygen as the hyperoxygenated plasma seeps across

I'm fairly sure you've convinced me that tissues that aren't well-oxygenated by breathing plain old sea level air might be subjected to higher levels of O2 while diving with nitrox, at least if done for the periods of time and O2 levels commonly used for hyperbaric oxygen therapies. Increasing the amount of O2 available to bones or burnt flesh isn't the same as meeting the normal metabolic requirements of vital organs that are satisfied by oxyhemoglobin while breathing 21% O2 at 1 ATA, so I still don't think you've offered anything to establish that diving with even 40% nitrox does anything to significantly increase the amount of O2 available for those normal metabolic processes.

How did you came up with 12% ?

40% O2 = 1.9 * 21%
4ATA = 4* 1 ATA
1.9 * 4 = 7.6 times more O2
7.6 * .31 ml/dl = 2.36 ml/dl
2.36/20 = .12

perhaps the millions of people with COPD hauling O2 tanks and wearing nasal cannulas might comment. They seem to be breathing EAN for a reason.

People with COPD breathe EAN because they have a problem with O2 transfer from the lungs to the hemoglobin (which doesn't appear to be the case with the OP). Unless they've got something else going on, whatever O2 does attach to hemoglobin transfers to the cells that metabolize the O2 just fine, as in those without COPD. Perhaps we could do some experiments on breath holding with those whose need to inhale is triggered by low O2 levels instead of increased CO2. If breathing higher concentrations of O2 results in more usable O2 in the blood then breath holding ability would presumably increase due to the extra O2 available for metabolism.

 

[PhatD1ver]

People with COPD breathe EAN because they have a problem with O2 transfer from the lungs to the hemoglobin (which doesn't appear to be the case with the OP). Unless they've got something else going on, whatever O2 does attach to hemoglobin transfers to the cells that metabolize the O2 just fine, as in those without COPD. Perhaps we could do some experiments on breath holding with those whose need to inhale is triggered by low O2 levels instead of increased CO2. If breathing higher concentrations of O2 results in more usable O2 in the blood then breath holding ability would presumably increase due to the extra O2 available for metabolism.

You might have missed a post. My doctor here in China believes that my heart condition is actually affected by the pollution here in China. Part of his interest in this is to see if the availability of additional O2 at partial pressure helps improve my lungs ability to transfer oxygen. Essentially, he thinks that as a result of my chronic exposure to Shanghai's pollution, that over time I develop what I guess you would call is PM2.5 induced COPD... the reasons for his thoughts is that I can go back to the US (Utah, Idaho, Wyoming) to high altitude enviroments, and within only a couple days, I can run and exercise without inducing one of my little cardio episodes (I still have my PVCs, but the exercise induced PSVT actions don't occur like in China).

So, his thoughts were to see what increased available O2, in the absense of the pollution factors might do for me... he really wanted to try was to see if on successive dives on Nitrox, my breathing improved. Since he couldn't come and tag along, and pull his blood samples, all I can go by is that I certainly FELT better. I wasn't as tired reboarding the boat (even after a strong swim against current), I had plenty of energy to go up 100 stairs to my room 3-4 times a day, and I didn't get a headache later on.

Long and short, is we are only going on what we observe in other aspects of my life. And trying to find workable solutions to make my diving safer and more enjoyable. And right now, comparing these 7 dives to the first 32 on air.. I'm going to lean to nitrox wherever possible.

 

[Polari]

Increasing the amount of O2 available to bones or burnt flesh isn't the same as meeting the normal metabolic requirements of vital organs that are satisfied by oxyhemoglobin while breathing 21% O2 at 1 ATA, so I still don't think you've offered anything to establish that diving with even 40% nitrox does anything to significantly increase the amount of O2 available for those normal metabolic processes.

If it works for with 100% oxygen why not with 40% ? Maybe will not be so efficient but still is quite good and you will see difference especially if you compare it with sea level oxygen at 0.31ml/dl instead 3.72ml/dl.Keep in mind we talked at 4ATM.The examples with hyperbaric oxygen therapies was at 3ATM.That makes it almost like [-]a 60% of oxygen.[/-] using 75% oxygen at 2ATM

In my mind is like this: Hemoglobin can carry a certain amount of oxygen and thats it.Blood can bring extra oxygen to the body.In our case more than 20% of the total and more than 50% of the tissue needs.
This is very important.The extra bit.Because this bit 20% of the total and more than 50% of the tissue is causing pressure and based on Grahm’s Law of Diffusion this extra oxygen is passing to tissue and even in places where hemoglobin can't penetrate.So now we have more than 50% increased oxygen to tissue

40% O2 = 1.9 * 21%
4ATA = 4* 1 ATA
1.9 * 4 = 7.6 times more O2
7.6 * .31 ml/dl = 2.36 ml/dl
2.36/20 = .12

Iam sorry i cant understand what you did here.Can you explain what 1.9 number is and how did you find it?

---------- Post added September 17th, 2014 at 02:27 PM ----------

40% O2 = 1.9 * 21%
4ATA = 4* 1 ATA
1.9 * 4 = 7.6 times more O2
7.6 * .31 ml/dl = 2.36 ml/dl
2.36/20 = .12

Ok i see now.You divide the EAN40 with the oxygen in the air.Correct? :shocked2:

Why not use Daltons Law ? I already posted that on the previous page:1. Boyle’s Law,2. Dalton’s Law,3. Henry’s Law,4. Graham’s Law

 

[ev780]

You might have missed a post. My doctor here in China believes that my heart condition is actually affected by the pollution here in China. Part of his interest in this is to see if the availability of additional O2 at partial pressure helps improve my lungs ability to transfer oxygen. Essentially, he thinks that as a result of my chronic exposure to Shanghai's pollution, that over time I develop what I guess you would call is PM2.5 induced COPD... the reasons for his thoughts is that I can go back to the US (Utah, Idaho, Wyoming) to high altitude enviroments, and within only a couple days, I can run and exercise without inducing one of my little cardio episodes (I still have my PVCs, but the exercise induced PSVT actions don't occur like in China).

So, his thoughts were to see what increased available O2, in the absense of the pollution factors might do for me... he really wanted to try was to see if on successive dives on Nitrox, my breathing improved. Since he couldn't come and tag along, and pull his blood samples, all I can go by is that I certainly FELT better. I wasn't as tired reboarding the boat (even after a strong swim against current), I had plenty of energy to go up 100 stairs to my room 3-4 times a day, and I didn't get a headache later on.

Long and short, is we are only going on what we observe in other aspects of my life. And trying to find workable solutions to make my diving safer and more enjoyable. And right now, comparing these 7 dives to the first 32 on air.. I'm going to lean to nitrox wherever possible.

So there you go. If you feel better then you feel better. All of us and our crazy theories can piss off.