New To Diving (Oxygen Question for experienced divers!)

[boulderjohn]

I ran into this thread this morning, and I had many things I wanted to say to dissuade the OP from his plan. Fortunately, I read through the thread first to make sure I wasn't just repeating what others have said. As I went, I crossed out all the things I was prepared to say. By the time I reached post #39, everything had been said and been said well. This post is just to congratulate the ScubaBoard community for a job well done!

 

[Lorenzoid]

. . .
Conclusion so far is that I didn't realize that the pressure in a wet atmosphere affects you much differently than in a dry atmosphere.

To elaborate on what tbone said in reply, it's my understanding that it's not whether your body is "wet" or "dry" that seems to make a difference in how the body reacts to O2. What IS my understanding then? My understanding is that researchers have found some evidence that the body reacts differently to a "ride" in a hyperbaric chamber and an actual dive, based on data collected from hyperbaric chamber use and data collected from divers. In other words, if I understand correctly, even the researchers are not sure what's going on and what causes it.

 

[boulderjohn]

My understanding is that researchers have found some evidence that the body reacts differently to a "ride" in a hyperbaric chamber and an actual dive, based on data collected from hyperbaric chamber use and data collected from divers. In other words, if I understand correctly, even the researchers are not sure what's going on and what causes it.

I recently learned that they do have an idea why this is true. Dr. Simon Mitchell explains it in this post.

Oxygen tolerance tests used to be a part of military diver selection processes, until they figured out that the test had no validity; in no small part because the principle risk factor (which you mention above) that most likely characterises an individual's risk is carbon dioxide retention, and carbon dioxide retention could not be factored into the old oxygen tolerance tests. When this was realised, attention shifted to testing individual diver's ventilation response to rising CO2 but this has also been abandoned pretty much everywhere (to my knowledge). Divers are not stupid and caught on to what the test was about. They would hyperventilate intentionally right from the start just to pass the test. In addition it is very difficult to replicate all the real-world contributory factors to CO2 retention (dense gas, immersion, resistance of UBA, exercise) in a single test protocol.​

 

[RayfromTX]

I ran into this thread this morning, and I had many things I wanted to say to dissuade the OP from his plan. Fortunately, I read through the thread first to make sure I wasn't just repeating what others have said. As I went, I crossed out all the things I was prepared to say. By the time I reached post #39, everything had been said and been said well. This post is just to congratulate the ScubaBoard community for a job well done!

I think this is my favorite boulderjohn post of all time.

 

[Stoo]

My understanding is that legit chamber-based therapy uses a very high ppO2... and the patient has a tender. Air breaks are incorporated into the therapy.

This can't be done safely in SCUBA. It can't be done safely without one, if not two, certified tenders. If you convulse on SCUBA, there's a very god change you're going to tox out and die.

I didn't notice what it was you are being treated for, but you plan sounds a bit short sighted.

 

[tbone1004]

My understanding is that legit chamber-based therapy uses a very high ppO2... and the patient has a tender. Air breaks are incorporated into the therapy.

This can't be done safely in SCUBA. It can't be done safely without one, if not two, certified tenders. If you convulse on SCUBA, there's a very god change you're going to tox out and die.

I didn't notice what it was you are being treated for, but you plan sounds a bit short sighted.

they crank the ppo2 up for DCS treatment, but the OP indicated the planned ppO2 is 1.5 for 60 mins which is less than what we use for deco. Unlikely to be worried about convulsions but that doesn't stop the training, tender, equipment requirement

for anyone curious
Hyperbaric Oxygen Therapy Can Improve Post Concussion Syndrome Years after Mild Traumatic Brain Injury - Randomized Prospective Trial

 

[oldschoolto]

Well let me say this now that it's been moved to dive med from the beginner forum...

In water treatments do work for me.. Like most things, There is not a easy way to understand why some stuff works for some people and not for others.. I have a table I follow that is very closely based on navy tables..

The cost and time was big.. And I had a lot of help.. I was lucky enough to have people in the right place to get me the tank and most of the system to operate the oxygen..

I also have 40 years of diving experience.

Jim

 

[kelemvor]

this is dicey as mentioned above.
The least unsafe way to do this is to get a nitrox diver cert, then get advanced nitrox only, *I think @uncfnp did something like that for a medical reason*,
then get and learn how to use a full face mask so when you give yourself an O2 seizure, you are less likely to drown $1k. At the same time, get a gas switch block $300, and an extra tank so you can take air breaks like you do in the chamber. Then make sure you have a support diver so when you seize, they can call 911.

Not that I'm really advocating the OP do HBOT in the water, but if she uses the ocean reef FFM you can hook two sources to the mask with no block. As I understand it you connect a second reg in place of the SAV. It would save the $300. Also if she skips the comms, the ffm can be had for closer to $500.
Still, your point stands. It's going to be an expensive undertaking.

 

[tbone1004]

Not that I'm really advocating the OP do HBOT in the water, but if she uses the ocean reef FFM you can hook two sources to the mask with no block. As I understand it you connect a second reg in place of the SAV. It would save the $300. Also if she skips the comms, the ffm can be had for closer to $500.
Still, your point stands. It's going to be an expensive undertaking.

saves the $300 but offsets with the cost of the regulator and adapter but yeah. I prefer switch blocks and don't like the ocean reef FFM's, but to each their own. If i was buying new it'd probably be the OTS Spectrum which is slick as all get out, but my personal one is a Poseidon Atmosphere

 

[kelemvor]

saves the $300 but offsets with the cost of the regulator and adapter but yeah. I prefer switch blocks and don't like the ocean reef FFM's, but to each their own. If i was buying new it'd probably be the OTS Spectrum which is slick as all get out, but my personal one is a Poseidon Atmosphere

I went with them because the diveshops in my town either don't sell FFM's at all or only sell ocean reef. Actually one shop had that weird scubapro FFM on their wall but none of the salesmen even knew anything about it. I wasn't willing to buy something so foreign to me online. OTS and Poseidon need a bigger dealer network, I guess. It would have been nice to have compared brands.