Addicted to Caffeine - increased risk of DCS?

[DandyDon]

Hey MM! :teeth:

Yes, we were talking about coffee and DCS (DeCompression Sickness) possibilities, but Charlie asked about coffee and "CNS (Central Nervous System) toxidity." Small case of changing lanes without a turnsignal, perhaps.

Oxygen Toxidity is something you'll learn about in Nitrox classes. Things like Padi suggest a "Soft bottom" of 121 feet maximum depth - for a maximum Oxygen Partial Pressure of 1.4 - when diving on 32% EANx - which has 32% Oxygen rather than 21% as found in air. Oxygen toxidity is not completely understood, so while Navy Divers will use a deeper depth with 1.6 as a limit on 32% Nitrox, we use the more conservative depth.

Additionally, while PCE (sudafed) is commonly used by air divers to helpo with equalizing, it's considered dangerous by Padi and DAN with Nitrox.

I think your porifle said you have your OW. Look forwad to AOW and Nitrox classes, which can be combined. Diving with 32% Nitrox can give you about 50% more bottom time below 60 feet, so Nitrox is related to DCS possibilities, but Charlie was asking about something else entirely.

And my analogy about the balloon one breath before exploding was a response to the idea of "Well, (some action) hasn't killed me yet." Yeah, we can get away with something, but we try to dive within conservative guidelines.

Sorry about the confusion, and I hope this explains...

thanks, don

 

[Charlie99]

BillP once bubbled...
The only study of caffeine and CNS oxygen toxitity that I'm aware of shows that it protects against hyperoxia induced seizures- in rats at least.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8574677&dopt=Abstract

Wow! some real studies, even if on rats! So far I had only seen some vague references in the PADI Nitrox manual to a 1995 American Academy of Underwater Sciences workshop, and a brief excerpt from Textbook of Hyperbaric Medicine by K.K Jain, et al. Both of them had caffeine in the "may increase the disposition to CNS tox" column.

Sorry about the thread hijack, or as DandyDon described it so eloquently, "changing lanes without turn signal"

 

[BillP]

dandydon said...


Additionally, while PCE (sudafed) is commonly used by air divers to helpo with equalizing, it's considered dangerous by Padi and DAN with Nitrox.

Howdy Don:

I'm sure you know much more about PADI than I, but while it would be a mischaracterization to say that DAN considers pseudoephedrine use with nitrox completely safe, I don't think they quite consider it "dangerous" either. Seems to me their position is more like "use with appropriate precautions".

A good article on their website about Nitrox (or "Enriched- air" as they call it) diving and pseudoephedrine can be found at:

http://www.diversalertnetwork.org/medical/articles/article.asp?articleid=51

Be sure you don't miss the paragraph headed "What's the bottom line?" toward the bottom of the article.

HTH,

Bill

 

[DandyDon]

BillP once bubbled...
Howdy Don:

I'm sure you know much more about PADI than I, but while it would be a mischaracterization to say that DAN considers pseudoephedrine use with nitrox completely safe, I don't think they quite consider it "dangerous" either. Seems to me their position is more like "use with appropriate precautions".

A good article on their website about Nitrox (or "Enriched- air" as they call it) diving and pseudoephedrine can be found at:

http://www.diversalertnetwork.org/medical/articles/article.asp?articleid=51

Howdy Bill!

Be sure you don't miss the paragraph headed "What's the bottom line?" toward the bottom of the article.

HTH,

Bill

It'd be a stretch to say I know more about PADI than anyone else with a C-card - from any agency/school. I am a PADI student only because that's what my Plainview and Lubbock instructors use, and my Amarillo instructor is just too far out of my usual path.

That PADI discourages the chemical found in Sudafed (PSE, which I erroneously referred to as PCE :nono: ) hit me when I was taking that course. I'm been living with hay fever type allergies all my life, and using PSE as a daily maintance OTC (Over The Counter) med since the more popular decongetant was pulled by the FDA (Food and Drug Admin). I counted on it and the anitihistamine included in the Walmart brand I took to prevent ear stoppage and motion sickness anytime I flew, more so when I free-dived, and more so when I started SCUBA. Suddently I had to stop using it on SCUBA?! I worried that I'd have equalizing problems, but I've had none. As much as I've blown my nose the last several decades, I have well stretched my E-tubes, I think.

THANKS for the link to the DAN articles. Going to have to study on that one a bit. Not an easy read for this cowboy. My saying that DAN discouraged diving on Nitrox was based on my :call: verbal communications with a medical technician there. It's certainly not a Yes or No, is it? Here's a link to another discussion I had on that recently:

http://www.scubaboard.com/showthread.php?s=&threadid=37019

On dive trips, I now take a 6-8 hour dose of PSE + antihistimine once after the last Nitrox dive of a day, a 24 hour anihistimine booster at bedtime, and just blow my nose as needed on dive days. Ever blow snot underwater? Need to raise your mask first!



don

 

[Belushi]

Then there will be death on a dive boat!!!
I have to have coffee, and it has to be strong enough to stand your dive knife in.
I am a prime candidate for DCS (overweight, dive too deep, dont exercise) so what the hell, life is too short for people around me to keel over due to my bad-assed attitude without coffee, what is one more pre-disposition?

 

[NJDiveGirl]

Thanks to all who answered my question - I'm going to go have a cup of coffee now!