Intermittent Recompression Stops

[Divesherpa]

Anyone have actual experience doing Intermittent Recompresssion Stops? Also, where is the best source for info that you are aware of?

Cheers and safe diving,
Sherpa

[WreckWriter]

Divesherpa once bubbled...
Anyone have actual experience doing Intermittent Recompresssion Stops? Also, where is the best source for info that you are aware of?

Cheers and safe diving,
Sherpa

Is this one of those things where if you don't know what it means you shouldn't comment on it?

[Divesherpa]

Definately

[Divesherpa]

:D

[WreckWriter]

Divesherpa once bubbled...
Definately

OK. "Recompression", as opposed to "decompression", has thrown me. That's generally a chamber term but I think you are one who knows what's he's talking about so I'll hang out and see what replies you get.

Tom

[caverkevin]

Sherpa,

could you offer some enlightenment as to what Intermittent Recompresssion Stops are?

Kevin Jones

[Divesherpa]

Hopefully, someone with far more knowledge on the subject will chime in and provide far more detailed answers to your query.
Intermittent Recompression Stops are "theoretically" used to pound bubbles into submission. During extended decompressions using deep stops (as per VPM), the subject (diver) descends back down 20-30 feet to allow the small bubbles to be reduced further. It is basically an attempt to break down the bubbles.
It is vital to understand that the bubbles have a layer on the outside that strengthens the bubble itself, which makes the bubble not want to decrease in size. This exterior coat on the bubbles has a great deal to do with why the bubbles don't go away faster and why our decompression is so lengthy.

Hopefully Weinke or someone else will chime in and explain this far better than I can. My knowledge on the subject is very limited, hence the post.

Cheers and I hope this helps,
Sherpa

[MikeFerrara]

I think this should be asked in the Ask Dr. Deco section.

I have never heard of doing such a thing during a dive but there are probably lots of things I,ve never heard of.

[mddolson]

I DO NOT KNOW THE ANSWER HERE!, but wouldn't periodic descents down 20-30 feet be creating a saw tooth profile?
While this is not a traditional saw tooth, because of the slope towards the surface, it is still a saw tooth.

Traditional Saw tooth profiles are known bubble generators , in higher risk of DCS and are to be avoided.

MikeD
:blfish:

[Divesherpa]

MikeFerrara once bubbled...
I think this should be asked in the Ask Dr. Deco section.

I have never heard of doing such a thing during a dive but there are probably lots of things I,ve never heard of.

I was asking for practical applications. Not theory. I've spoken with Eric Baker on the issue. He's the dude that runs comparisons on JJ after WKPP dives. He mentioned the point.
Can this be moved back to where PRACTICAL APPLICATION can answer?

[MikeFerrara]

Divesherpa once bubbled...


I was asking for practical applications. Not theory. I've spoken with Eric Baker on the issue. He's the dude that runs comparisons on JJ after WKPP dives. He mentioned the point.
Can this be moved back to where PRACTICAL APPLICATION can answer?

Sorry Sherp I didn't intend for them to move the thread (nobody else listens to me. I just thought there would be a better chance that someone would have the answer. I know who Eric Backer is but have never heard this theory. I guess I would be interested in hearing about it also.

[Spectre]

I moved the thread to Ask Dr. Deco as I agreed with Mike and believed it better served there... as well as having a good chance Dr. Deco'll see it and provide us with his input. However if the original author wants it here, then who am I to argue.

And a side effect of the move results in a reference in the Dr. Deco forum pointing to this thread anyway...

[Divesherpa]

Thanks for replacing, Spectre. I was hoping to hear from someone who is actually doing it more than someone who knows the theories. I value both, but don't want to be the guinea pig!:bonk:

[100days-a-year]

Sherp,have you ran a variety of these profiles on your deco programs to see what happened?Just for giggles of course until someone knowledgeable shows up.

[Divesherpa]

The problem is that the software is not taking the info into account, sort of like some software doesn't take deep stops into account.

The equations that set up deco are mostly single var. DE's. It's fairly common sense to see the limitations of such a manner of calculating deco.

Cheers,
Sherpa

[Dr Deco]

Dear Divesherpa:

To my knowledge, no one has tried this type of decompression in a laboratory trial. A few years ago, I believe that I was shown a decompression schedule by Dr Michael Gernhardt that illustrated “spiked decompression.” The point of all of this was to increase the internal pressure of the gas in the gas bubble and cause it to diffuse into the tissue. The trick was to do this in such a fashion that you would get an overall net positive effect. That is, you would dump gas from the bubble faster than you would add gas to the tissue. We would jokingly refer to this as “shaking the bubbles loose.“

In the absence of a laboratory test, this must be modeled and the end result will depend on the parameters that are chosen. It is a relatively complicated situation to model mathematically.

I regret that I do not have any practical knowledge of this, as I have never heard of anyone actually doing anything of this nature.

Dr Deco:doctor:

On vacation this week.

[Divesherpa]

Thanks for the reply, Dr. Deco

The "shaking the bubbles loose" analogy is how it was explained to me as well.

Enjoy your vacation. When you get back, hopefully the discussion will continue.

Cheers,
Sherpa

[jbd]

some months back I saw a TV program that involved divers from Britain and one of the techniques they were using was what they called reverse profile diving the purpose of which was to crush and or shake loose bubbles.

This isn't exactly the same thing you are asking about but maybe you could ask some of the British diving brethen about this. It may or may not lead you to the info you are looking for.