On Mon, 24 Jul 2000 09:13:08 -0100, Kuty <[log in to unmask]> wrote:

>I bring it here with no snips:
>
>"jim frei" <[log in to unmask]> wrote in message
>news:3974BE1A.9005A728@stormwatergroup.com...
>> my story - i got bent doing an experimental dive study.

The story gave a STRONG indication of an ill-DESIGNED experiment
conducted by DAN (Diver Alert Network), based on volunteers who
are strong in courage and weak in scientific as well as common
sense.

Quite a while back, the same Jim Frei posted some conclusion about
his role in DAN's experiment on how long to wait till "safe to fly",
posing himself as a "researcher" when he was merely a voluntary
"human guineapig" in the dive until you get bent "design", by
progressively shortening the surface interval in some arbitrarily
chosen profiles.  Similar flaws in this design.  Same uninformed Mr.
Frei.  He was just an accident waiting to happen, and it did.

BIG SNIPS to get to a couple of cogent points:

>> As an avid scuba diver, I'm also interested in diving
>>physiology, diving safety, and of course DCS theory.
>> Therefore, I participate as a research subject in diving
>>studies conducted by Divers Alert Network (DAN) and Duke
>>University Medical Center (DUMC) at Duke's hyperbaric
>> chamber.

The "therefore" part doesn't logically follow.  The "research
subject" is an euphemism for "guineapig".  If he is interested
in "diving physiology and diving safety", he should have READ
about those subject FIRST until he had a good grasp of what
the risks ARE, and could have avoided what happened to him.
He was VERY FORTUNATE in his apparent recovery from a Type II
DCS.  From his detailed description, he seemed to have been
still completely oblivious to the obvious FLAWS that I am going
to point out below.

>> The study in which I participated is an Ascent Rate Study
>>where various profiles with an ascent rate of either 10 feet
>>per minute (fpm) or 60 fpm are compared.

But if the ASCENT RATE was being compared for those two rates,
then the dive profiles THEMSELVES should not have been those
for which DECO stops are REQUIRED (according to tables) but
SKIPPED.  At best, the effects of "missing deco" and "fast
ascent" are CONFOUNDED (technical term in experiment design).

>>I had successfully
>>completed about eight previous profiles in this study.  The
>>profile that bent me was to a depth of 100 feet sea water
>>(fsw) for 30 minutes with a 10 fpm ascent.

That was a DECO dive.  He didn't describe what the other eight
profiles were ... but it appeared to be a similar "design" of
progressively deeper/longer till bent.


>> I entered the chamber where I began a Navy Treatment Table
>>6.  This table starts at a depth of 60 fsw and then ascends
>>to 30 fsw while breathing cycles of Oxygen.  During this
>>table, my conditions worsened, and I became paralyzed from
>>the waist down.  The doctors immediately commenced with
>>Treatment Table 7 which compresses to a depth of 165 fsw for
>>two hours, then slowly ascends for the next 58 hours.  I am
>>breathing cycles of Oxygen during this time.

ANOTHER blunder by the chamber "technicians" who misdiagnosed
the severity of the MISSED DECO, and applied the WRONG TABLE
Treatment which made things worse.

>> Why did I get bent?  That's the million dollar question -
>>there is still so much unknown about DCS and the human body.

That's a two-dollar question.  While there's much unknown about
DCS, there is PLENTY KNOWN, which should have kept this
"accident" from happening.

>>The profile that bent me was long according to most
>>recreational dive planning tables,

An obvious understatement.

>>but the ascent rate (10
>>fpm) is much slower than most divers practice in open water.

So?

>>Therefore, I thought the risk was tolerable for my own
>>personal comfort level.  Unfortunately, the odds were
>>against me, and I got hit bad.  I still feel that diving is
>>safe (or safer) as driving a car or many other activities we
>>pursue.  To avoid getting bent with 100% certainty, then
>>divers should not dive.

The TRAGEDY of this case was that he hadn't learned A THING
from it, as he SHOULD HAVE, by now.

>> A ultrasound test during my treatment showed a patent
>>foramen oval (PFO), or hole, in my heart septum.

That's the JOINT FAULT of DAN (which conducted the experiment
on volunteers) and Mr. Frei himself (who volunteered to be a
guineapig)!   PFO is a KNOWN contributor to DCS.  DAN should
have REQUIRED all volunteers to be tested for PFO before any
DCS;  a prudent volunteer should have KNOWN to have himself
tested even if DAN didn't require it!

>>I have completed over 300 dives with no hint of DCS since
>>1991.

An accident waiting to happen!  For progressively "pushing the
limits" and BEYOND.


>>an important role.  My advice is that if you plan to
>>regularly dive deep (> 100 fsw) and long (pushing the no-
>>deco limits) then you may want to consider getting tested
>>for the presence of a PFO - then you can choose your level
>>of risk with one more fact to consider.

He was finally HALF-AWAKE to the FACTS.  Diving deep (>100 fsw)
is the least of all concerns.  It's the MISSED DECO STOPS that
mattered.  He could have been diving much shallower and missed
similar DECO STOPS and ended the same.  The PFO testing, in
the context of HIS participation in the experiment, should
have been a MANDATORY requirement, not a "you may consider".

He considered all the relevant factors TOO LITTLE and TOO LATE,
and still didn't seem to have learned the importance of those factors,
and the importance of NOT missing deco stops.

A comedy/tragegy of ERRORS compounded.

>> I fully support DAN and its mission to improve diver
>>safety.

Then DAN should learn to DIR (relative the DESIGN and EXECUTION
of experiments involving human guineapigs)!


>>It was just my unlucky turn to get hit.

Playing Russian Roulette REPEATEDLY and didn't get "hit" until the
nineth trial is not exactly what I would call "unlucky turn".


>>Like they say, if you don't want
>>to get bent, then don't dive.

A true statement that DOESN'T APPLY to the incident reported.


>>At least a lot of knowledge
>>will be gained from this incident,

A lot of knowledge HAD ALREADY BEEN KNOWN before the incident --
which neither DAN nor Frei took the precautions to consider.

>>and I feel proud that I
>>have contributed to the body of science.
>
>********************************************
>
>
>End of quote.

He was very fortunate, because he could have contributed his
DEAD body, without gaining any NEW knowledge to science!

-- Bob.