Deep stops -practice and theory

[Santa]

I've read an article by this Ichtyologist-whose-name-eludes-me-now-but-whom-I'm sure-several-of-you-must-be-familiar-with-since-his-subject-is-controversial. That guy.

He introduced the idea of deep stops to minimize overall fatigue and bubble formation during ascent. As I understood it a nonaggressive ascent combined with stops at certain points would allow micronuclei to "settle" in stead of growing into bigger bubbles and stressing the tissues.

As it applies to recreational diving I was thinking maybe the occasional deep stop would provide some actual "recreation" during heavy multiday diving - I imagine it would be rather easy to integrate with your average multilevel profile.

So my questions are:

1. Are there any confirmed scientific data on the subject.
2. If not, is there at least a worthwhile attempt at an explanation of what is going on inside the tissues.
3. How would you calculate such deep stops within a given profile.


regards

 

[Santa]

whoops. Think this thread was probably redundant. Already a popular subject. Sorry.

 

[Charlie99]

https://www.daneurope.org/eng/lettmed.htm about half of the articles are related to this.

http://www.gap-software.com/staticfiles/deepstops.pdf

 

[Dr Deco]

Hello Santa:

Richard Pyle

The ichthyologist to whom you are referring is Richard Pyle. He noticed how much better he felt after pausing deep in the water. In this case, the pause was done to bleed air from the swim bladders of the fish.

In Pyle’s scheme of things, he pause halfway between the bottom depth and the depth of the first stop. He waited there for about five minutes.

Studies

There have been some studies that demonstrate that slower ascents, or pauses, will decrease bubble formation, as detected by a Doppler bubbles detector.

Reason

The idea behind all of this is that micronuclei in the tissues do not grow if they are kept small as the dissolved nitrogen escapes into the capillaries.

If the bubbles are constricted by surface tension, they will remain small. If an ascent is made quickly to the surface, the nuclei will expand to the point where surface tension is less than the dissolved nitrogen partial pressure. The nuclei will then grow into frank bubbles. If they grow enough, DCS is possible.

One should perform a search on this site for micronuclei. this topic has been discussed many times in detail over the last five years.

Dr Deco :doctor:

Readers, please note the next class in Decompression Physiology is September 10 – 11, 2005 :1book:
http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[Doc Intrepid]

Here are a couple sites that offer a small literature review:

http://www.rgbmdiving.com/site/decopap.htm

http://www.hhssoftware.com/v-planner/vpmdetail.html

http://www.decompression.org/maiken/VPM/VPM_Program_Site_Map.htm

Poking around these for awhile may prove useful...

Doc

 

[Santa]

Thanks a bunch guys!!

I'll hit the screen/pages/books


sincerely