Anybody remember this thread? Nov. 2000 uk.rec.scuba

On 25 Apr 2004 11:38:30 GMT, Alasdair Allan <aa@ukrecscuba.org.uk> wrote:

>Lee Bell wrote:
>> I don't think I've seen anybody recommend in water recompression as a
>> preferred method when there's a chamber available.
>
>Absolutely, when there is a chamber available, use the chamber. But there
>are many places aroudn the world where a chamber isn't available. In these
>cases IWR is the only option...
>

The pearl divers out of Broom in Australia use/d in water deco on a daily basis.
It is banned offshore here now.

--
Steve Barlow

Steve Barlow <steve@steve-barlow.fsnet.co.uk> wrote:

> The pearl divers out of Broom in Australia use/d in water deco on a daily basis.

Um...
Isn't that what we do?

nigelH

"Steve Barlow" <steve@steve-barlow.fsnet.co.uk> wrote in message
news:j73o809mhdiagfluoemv9f61gqp04v6vdq@4ax.com...
> On 25 Apr 2004 11:38:30 GMT, Alasdair Allan <aa@ukrecscuba.org.uk> wrote:
>
> >Lee Bell wrote:
> >> I don't think I've seen anybody recommend in water recompression as a
> >> preferred method when there's a chamber available.
> >
> >Absolutely, when there is a chamber available, use the chamber. But there
> >are many places aroudn the world where a chamber isn't available. In
these
> >cases IWR is the only option...
> >
>
> The pearl divers out of Broom in Australia use/d in water deco on a daily
basis.
> It is banned offshore here now.

I wonder if we're talking about the same thing here. We're talking about in
water recompression, a process for recompressing and then slowly
decompressing a diver who is, otherwise, expected to be severely bent. It's
a somewhat risky process generally employed only when a recompression
chamber is not readily available and is occasionally employed between the
time of the incident and the first chance to transport the victim to a
recompression chamber.

Deco is what divers do in the water to avoid having to do in water
recompression or spending time in a chamber.

Lee

On Mon, 26 Apr 2004 00:27:13 GMT, "Lee Bell" <leebell@ix.remove.netcom.com>
wrote:

>"Steve Barlow" <steve@steve-barlow.fsnet.co.uk> wrote in message
>news:j73o809mhdiagfluoemv9f61gqp04v6vdq@4ax.com.. .
>> On 25 Apr 2004 11:38:30 GMT, Alasdair Allan <aa@ukrecscuba.org.uk> wrote:
>>
>> >Lee Bell wrote:
>> >> I don't think I've seen anybody recommend in water recompression as a
>> >> preferred method when there's a chamber available.
>> >
>> >Absolutely, when there is a chamber available, use the chamber. But there
>> >are many places aroudn the world where a chamber isn't available. In
>these
>> >cases IWR is the only option...
>> >
>>
>> The pearl divers out of Broom in Australia use/d in water deco on a daily
>basis.
>> It is banned offshore here now.
>
>I wonder if we're talking about the same thing here. We're talking about in
>water recompression, a process for recompressing and then slowly
>decompressing a diver who is, otherwise, expected to be severely bent. It's
>a somewhat risky process generally employed only when a recompression
>chamber is not readily available and is occasionally employed between the
>time of the incident and the first chance to transport the victim to a
>recompression chamber.
>
>Deco is what divers do in the water to avoid having to do in water
>recompression or spending time in a chamber.
>
Point taken Lee, I got the wrong end of the stick.
The pearl divers work around the 30m level on surface demand with the boat
towing them along, they carry out their stops in water as we do.
Offshore that is not allowed and the (air) divers are brought to the surface
then put in a chamber to carry out the omitted stops.

--
Steve Barlow

"Steve Barlow" wrote

> >I wonder if we're talking about the same thing here. We're talking about
in
> >water recompression, a process for recompressing and then slowly
> >decompressing a diver who is, otherwise, expected to be severely bent.
It's
> >a somewhat risky process generally employed only when a recompression
> >chamber is not readily available and is occasionally employed between the
> >time of the incident and the first chance to transport the victim to a
> >recompression chamber.
> >
> >Deco is what divers do in the water to avoid having to do in water
> >recompression or spending time in a chamber.
> >
> Point taken Lee, I got the wrong end of the stick.
> The pearl divers work around the 30m level on surface demand with the boat
> towing them along, they carry out their stops in water as we do.
> Offshore that is not allowed and the (air) divers are brought to the
surface
> then put in a chamber to carry out the omitted stops.

Interesting. That's a fairly common practice with divers working on
construction and similar projects. I think I recall hearing that the U.S.
Navy uses similar procedures for some of their diving. I was not aware it
was also being used by pearl divers. I suppose it's a reaction to the
reports we used to bet about how often pearl divers got bent. It seems that
they were not entirely aware of the consequences of their profession and the
operators that hired them were quite content with bending their employees to
put a few extra dollars in their pockets.

Lee

[re-send owing to server probs]

Lee,

> I don't think I've seen anybody recommend in water recompression as a
> preferred method when there's a chamber available.

The discussion had proceeded without any mention of chamber availability. It
appeared to me that people were discussing a first response to a serious
decompression accident while waiting for evacuation to a chamber. Noone had
said that in the UK rapid evacuation to a chamber is usually possible and
IWR is not a sensible option, especially for someone who is very ill. Even
in remote locations, it would be an absolute last resort when the nearest
available chamber was many hours away.

> Further, the 18 meter
> equivalent for "standard chamber treatment" is not IWR, it's chamber
> treatment . . . and it's correct.

In response to Alun's suggestion that you would need to go "incredibly deep"
for IWR, Iain said "Why not 18m on O2 with a full face mask? (Hint: that's
what they use for a standard chamber treatment)". The context suggested he
was talking about in-water recompression. I pointed out why that is not a
good idea and was inconsistent with the IWR schedule he later outlined.

> > A deep, rapid ascent, as in the original example, may well be followed
by
> > impaired consciousness, nausea, or vomiting, which are all
> contraindications
> > to IWR.
>
> Beats death every time. Let's not lose track of the fact that this is a
> thread that started with one diver dead on the spot and another dying in
the
> chamber.

You are going to be lucky to survive the type of incident described no
matter what the first aid or treatment. In serious cases, IWR will probably
make matters worse. The Australian or US Navy IWR schedule referred to is a
last resort and is not intended for severe DCI.

> Use of a full face mask is specifically for the purpose of dealing
> with possible oxygen toxicity as well as unconsciousness.

A full face mask should prevent drowning if the patient convulses or passes
out, but you would not send someone to 9m on oxygen if they are already
nauseous or have impaired consciousness. If the patient becomes unconscious,
you would need to surface them, so you could manage their airway and monitor
their vital signs. Vomiting into a FFM is going to be problematic,
especially for someone not otherwise in control. If they convulse, you have
to get them off oxygen ASAP, so you would need to rescue a fitting diver to
the surface in a hurry. A FFM does not allow you to carry on with IWR in
spite of these problems.

I don't know where the incident in the original example occured. However,
this is a UK newsgroup read by a wide range of divers. If someone is going
to suggest the use of IWR (e.g. "O2-based IWR would be the realistic
option"), I think they have a responsibility to be absolutely clear about
the circumstances they are referring to.

Phil S.

> I don't know where the incident in the original example
> occured. However, this is a UK newsgroup read by a wide range
> of divers. If someone is going to suggest the use of IWR
> (e.g. "O2-based IWR would be the realistic option"), I think
> they have a responsibility to be absolutely clear about
> the circumstances they are referring to.

If you're going to quote me, please do so in context. Alun described an
air-based IWR schedule, concluding:

> That's not to mention the kind of support you need to do a 21
> and a half hour dive.

In that context, the O2-based IWR schedule I described does indeed seem to
be a more realistic option.

However, I accept your point that, "Noone had said that in the UK rapid
evacuation to a chamber is usually possible and IWR is not a sensible
option, especially for someone who is very ill. Even in remote locations, it
would be an absolute last resort when the nearest available chamber was many
hours away." with which I agree completely. In my haste, I assumed that this
was understood.

Re: depth of the Australian method vs my comparison with chamber
recompression. My mistake and my fault in dashing off a response on my way
out the door without ensuring that what I wrote actually made the sense that
I meant it to. I was trying to counter Alun's contention that IWR had to be
"incredibly deep" and used the chamber pressure to illustrate this. As you
pointed out, I failed to stress that the "Australian" IWR protocol is even
shallower (although I believe the "Hawaiian" protocol involves a deep air
spike first)

Iain

Iain,
It seems we are talking about presentation rather than substance.

"Iain Smith" <iainmsmith@btinternet.com> wrote in message
news:c6jg41$crs7v$1@ID-228623.news.uni-berlin.de...
> In that context, the O2-based IWR schedule I described does indeed seem to
> be a more realistic option.

More realistic than IWR on air certainly, but hardly ever advisable
nevertheless. I accept that your intention was to counter Alun's conclusion
that IWR is impracticable, but it is such a serious issue that anything that
might be taken as a recommendation should be carefully circumscribed. I
suspect that some divers wouldn't take too much encouragement to try to
treat themselves, rather than bother the emergency services.

Phil S