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> 
> >I don't understand how IWR on pure O2 can make the symptoms worse either
> >during or after the treatment. Considering that the alternative treatment
> >is just O2 at 1 atm, how could doing it near 2 atm make things worse? I
> >am assuing that proper procedures are followed (full face mask, warm suit,
> >etc), of course.
> 
> Oxygen diffusing into existing air bubbles will cause a transient growth 
> phase before shrinking.  Symptoms could worsen temporarily.
> 
> regards,
> 
> David Doolette
> ddoolett@me*.ad*.ed*.au*

	The theory that DCI is caused by a bubble lodging somewhere
(discussed in a previous post - there is evidence that this is not
always, or even often, the case), leads to the idea that having a
lodging (and therefore large and critical) bubble somewhere and
squeezing it isn't a hot thing to do.

	You don't immediately (or rapidly, it takes a lot more pressure
and time to redissolve a bubble than that which formed it) get rid of
the bubble during IWR. The treatment causes i) rapid alleviation of
symptoms by compressing the bubble and moving it on, before local
clotting occurs, and cell death begins, and ii) resolution of the bubble
as N2 in the body equilibrates to ambient i.e. zero.

	In water, and therefore variable pressure, recompression,. would
lead to the bubble leaving a known lesion site, and potentially
re-sticking somewhere else, possibly a lot worse.

	The theory against IWR, as based on this theory, is *very*
*very* sound. The difficulties with applying it are;

	It doesn't seem to be true. As a previous poster has commented,
there is a large and growing body of opinion which says that bubble
formation triggers DCI but is not necessarily involved in the continued
development of the lesion; and also, IWR seems (based strictly on
reports and discussions based here) to work. Which it shouldn't. So the
theory is probably wrong!

	But that's why IWR might make you worse anyway.

	Jason. Stuffing his turkey with Haggis, not Lamb. :-)


> 
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