RBC's & PPN2

[Lost Yooper]

Bill, I agree wholeheartedly with you. Like I said, these guys are not scientist and their idea of what is fact (and how to achieve fact) is probably different than a scientist. They may not even care, so long as it works.

As for how George and JJ feel afterwards, it's certainly not going to be cell rigidity (at least not alone). They feel good because they don't have any bubbles in their system after shortly after diving. George clears in 30mins which is good even among his guys. The funny thing is that they seemed to clear faster if they took their breaks from O2 on a very rich helium mix. I think they'll be going to straight heliox someday -- I beleive it was Bill Mee that was using heliox with those guys with good success.

Good stuff.

Mike

 

[100days-a-year]

LY, if you'll remember. AUE Mike stated they use 50/50 HeO2 and get out clean and early often doing multiple dives per day. I wonder if there is any connection. If you want to see if someone mental accuity is affected by deep air...talk to Hal Watts. He's mentally and physically sharper at twice the age of most other leaders in the Tech community. I don't use it, but he flies in face of a lot of recent claims about deep diving.

 

[Lost Yooper]

Tony,

Yeah, there seems to be something going on with the helium. The mysteries are still being sorted out and the myths put aside.

The long term physical effects of deep air seem to be up in the air. The short term effects of deep air while underwater are only in dispute by those who reap the financial rewards of teaching it and those brainwashed by their teachings.

Take care,

Mike

 

[100days-a-year]

Mike, tru dat...most of the old guys I know use helium under 150' some 130'. Guys I dive with started teaching mix years ago. Just like nitrox a lot of'em used it way before it was common. Surprise they're still alive and a few courageous knuckleheads using air ain't.

 

[Dr Deco]

Dear Readers:

I too like to hear what “recreational divers” are doing in the field. There are several reasons:

• There are only so many scientists and so many laboratories; not everything can be done,
• There is only so much money, and barophysiology is not high on the list of “national health concerns”
• Much information can come from “wild” things that individuals do – things for which it would be difficult to secure approval for a human subjects committee (sounds a little ghoulish);
• Accidents do happen and often information can be gleaned from misfortune
• Scientists have a very strong bias from their classical training (most, e.g., do not believe in micronuclei control). They seldom are adventursome.

It is this type of information that is very valuable to a researcher such as I am. Other scientists would not agree that it was worth much.

Dr Deco
:doctor:

 

[Lost Yooper]

Whoa Doc, that was a cool post! Now how many docs have the guts to say something like that, eh?

The differences between theoretical/scientific and real life can be unbelievable in many facets of diving (ox tox, helium diving, deco procedures, etc.) as shown by some extreme divers out there.

I respect that doc.

Mike

 

[Lost Yooper]

Hello again,

I found this little tid bit on red blood cells and thought I'd post it.

Billy W. adds the following, "And the real horror of deep air - if you survive the narcosis & high pp02, is the systemic physical damage caused by RBCs which stiffen in the presence of high ppN2. The rigid RBCs then block capilliaries and damage the fragile lining of the micro-circulatory system. This is where delicate, finely perfused tissues like the nervous system and the retinas sustain permanent damage." -- Thanks Bill!

Source:

http://www.fotofixer.com/1deepDivingonAir.htm

I don't know who Billy W. is, but I found the statement "This is where delicate, finely perfused tissues like the nervous system and the retinas sustain permanent damage" to be interesting.

Mike

 

[BillP]

Hi Mike:

Yes, what Mr. Gudmundsen and "Billy W" say about nitrogen and RBC's is indeed interesting, but as is usually the case with this subject they provide no evidence to support why they say it.

I also think it would be interesting if someone concocted a dissertation explaining how "the real horrors" of deep air diving are associated with alien abductions. They might be able to come up with very detailed descriptions of how aliens are involved, but personally I would want to see some evidence to support the claims before I believed them. (Even if it was someone like Scott Gudmundsen or "Billy W" making the claims.) It might be true, but until they can show some sound evidence it's just an interesting idea to be investigated and not a "fact" to be repeated as truth.

But hey, if you read it on the Internet it must be true, eh? (grin)

More of my 2¢,

Bill

 

[Lost Yooper]

Hey Bill,

I just posted it to see if you or anyone else might know that guy Billy W., and if what he said makes any sense. This is the first I had heard of potential retina damage and thought maybe there might be additional stuff on retina damage and deep air diving out there.

I'm trying to get a hold of Scott G.

Mike

 

[BillP]

Hi Mike:

Yes, there is "additional stuff" on changes in the retina and diving, but not specifically retina changes related to deep air diving, as far as I know.

It's been known a long time that hyperbaric oxygen can cause changes in vision and that decompression illness can cause problems in the eye. (Sir Robt. Boyle noted a bubble in they eye of a decompressed viper in 1670!) Best I can tell, the study that seems to have started the discussion about retina changes in divers appears to be a British study by Polkinghorne, et. al. (1) published in the journal Lancet in 1988. In their study they compared the retinas of divers vs. non-divers and found more lesions in the retinas of divers. The lesions in the divers' retinas were for the most part explained by previous episodes of decompression illness, but not all of the increase in the number of lesions could be explained by known DCI in the divers. They concluded that diving causes an increase in retina lesions and proposed several possible mechanisms as to how that might happen.

Now to get deeper into your question and the topic at hand, they divided the divers by both number and depth of dives made -including depths over 50m. (They didn't specifically say, but all the dives appear to have been made on air.) They found that divers with an increased number of dives had an increased incidence of retina lesions, but they did not find an increased number of lesions in "deep air" divers. They specifically state in the study that, "There was no relation between either pigment epithelial defects or capillary density" (the changes in the retinas they were looking for) "and depth of dives, interval since last dive, or depth of last dive." They also noted that, "no subject had any visual loss as a consequence of diving."

In a followup study by Holden, et. al. (2) published in the British Journal of Sports Medicine in 1992 the authors point out the the Polkinghorne study included both sport and professional divers and included divers with less than exemplary dive practices. In their study of amateur divers with 10+ years experience who followed "safe diving practices" vs. non-divers they found no differences in the retinas.

There are other studies too. A French study (3) found changes in color vision in sport divers, but no changes in retinas and no correlation with any particular type of diving (like deep air?). A study of Royal Navy divers (4) found no difference in the retina exams of divers vs. non-divers.

So to answer your question, what "Billy W" said about the "the real horror of deep air" doesn't make any sense to me. Now, if he had called it an "interesting question about diving (not specifically deep air diving) that is totally unproven but worthy of further investigation", he would be making some sense IMO. But a "real horror"? I have yet to be convinced. If you can find out who he is and he can come up with some evidence to support his claims, I'd be interested though.

HTH,

Bill

1. http://www.ncbi.nlm.nih.gov:80/entr...eve&db=PubMed&list_uids=2904521&dopt=Abstract

2. http://www.ncbi.nlm.nih.gov:80/entr...eve&db=PubMed&list_uids=1623365&dopt=Abstract

3. http://www.ncbi.nlm.nih.gov:80/entr...ve&db=PubMed&list_uids=10844306&dopt=Abstract

4. http://www.ncbi.nlm.nih.gov:80/entr...eve&db=PubMed&list_uids=8673182&dopt=Abstract