In-Water Recompression, Revisited

[Akimbo]

Definitely concur with your comment about time to treatment influencing outcome, that is borne out in the literature. That is one of the advantages of IWR in the proper hands.

I seem to remember some debate several or more years ago arguing that a study showed it didn't matter. As I remember, the study was comparing some (what was to me) crazy-long times to treatment like hours versus a day. Do you remember which one that is? I think it might have been an old NEDU paper.

I'm actually relieved... I was starting to wonder if I was in some kind of alternate universe.

On a slightly more serious note, I have often mused that dive computers need a "time to the nearest chamber" risk factor right next to the age and exertion risk level options.

 

[Wookie]

IOn a slightly more serious note, I have often mused that dive computers need a "time to the nearest chamber" risk factor right next to the age and exertion risk level options.

Hey, now!!!

 

[Akimbo]

Hey, now!!!

At least you're operating in chopper range and can raise the Coast Guard on VHF. I'm put-off by 3 days underway to the nearest landing strip and another 10 hours flight. This one is bad enough:
Alert Diver | Bent in Chuuk

Edit: levity recognized, but was too good a backdrop for my ongoing rant

 

[Akimbo]

The new multi-place chamber the Navy is putting everywhere is the bomb.

I know that is a popular phrase at the moment but may not be the best option to praise a pressure vessel... maybe it's just me.

 

[dberry]

I know that is a popular phrase at the moment but may not be the best option to praise a pressure vessel... maybe it's just me.

In my line of work it's common practice to refer to high pressure vessels as bombs. These are chemical reactors designed to operate at 3500psi and higher. Up until some remodeling a few years ago our building had a "bomb room" with thick concrete walls and a blow-out ceiling. Of course pressurized gas isn't the only source of explosions in a chemistry building...

 

[Akimbo]

Up until some remodeling a few years ago our building had a "bomb room" with thick concrete walls and a blow-out ceiling.

The Naval Ocean Systems Center had (has?) a room like that near the machine shop. I was an electronics tech on the Bathyscaphe Trieste II and we pressure tested every housing and cable that would fit inside.

They took a 14" gun barrel made for a battleship, cut it to around 12' long, plugged the open end, and dropped it breech-up in a hole in the ground. The gauges were 30,000 PSI but we only ran it up to 13,500 PSI or 1.5x working depth. The room's walls were like a bunker but the roof was plywood... seamed pretty weird to me until someone explained why. I never gave much thought to a failure before that and it became clear why they gave such an important job to the such a low ranking guy like me.

Still, saturation divers are pretty sensitive about calling their home away from home a bomb.

 

[northernone]

I seem to remember some debate several or more years ago arguing that a study showed it didn't matter. As I remember, the study was comparing some (what was to me) crazy-long times to treatment like hours versus a day. Do you remember which one that is? I think it might have been an old NEDU paper.

I'm actually relieved... I was starting to wonder if I was in some kind of alternate universe.

On a slightly more serious note, I have often mused that dive computers need a "time to the nearest chamber" risk factor right next to the age and exertion risk level options.

Perhaps this one? Sounded similar to your recollection.
Delayed Recompression for Decompression Sickness: Retrospective Analysis

 

[Akimbo]

Perhaps this one? Sounded similar to your recollection.
Delayed Recompression for Decompression Sickness: Retrospective Analysis

I don't think so... this one is even worse. Comparing <48 to >48 hours is silly for our (divers) purpose. Both are Delayed Recompression, approaching criminal (IMHO).

Brace for a rant, not directed at you: Think about it. Would anyone be surprised if there was very little difference between leaving a tunicate on your arm for two versus three days? Nobody would work under a commercial diving supervisor that waited 48 minutes to treat. Would you use a dive boat that waited 48 minutes to give you Oxygen on deck?

OK, I know that shore based hyperbaric centers aren't going to get divers at their door fast enough for true emergency DCS treatment... as-in preventing damage through compression and maxing-out ppO2. They do hyperbaric and medical therapy, as-in trying to repair damage. For all practical purposes, diluent gas is out of your system in 24 hours. DCS leaves behind a lot of inflammation and compromised tissue just like many other forms of trauma. HBOT can accelerate healing most trauma, though relatively underused due to cost and availability. Docs would prescribe HBOT all the time it if it were as cheap as Advil. Leaving many traumas untreated too long often makes recovery less complete because continued inflammation causes damage and scar tissue forms (layman over-simplification).

Timely and well-executed IWR is for hyperbaric treatment, not therapy. Think damage control at sea and leave repairs to pros like @Duke Dive Medicine's team.

 

[cerich]

Still, saturation divers are pretty sensitive about calling their home away from home a bomb.

then again it is more like a kiln when things go wrong most of the time

 

[Kay Dee]

@boulderjohn referred to you as Kathy earlier. My apologies, no offense was intended. If you'll provide your preferred pronoun I'd be happy to use it.

Re the word "asymptomatic", that means something very specific to me, and your description, "Three and a half or so hours later I walked out of the water and other than taking six weeks off diving on a doctor’s subsequent advice (which in retrospect I somewhat regret, as I now think that duration was somewhat excessive) I was not much the worse for wear..." was a little nebulous, thus my fudging of the term. So for clarity, you suffered from severe neurological DCS, underwent IWR on a "modified" Australian table (I'm assuming you stayed with 30 feet, please correct me if I'm wrong), and had complete resolution of your DCS symptoms, yes?

Have a pleasant evening!

Best regards,
DDM

Well first, no offense whatsoever taken, I guess I missed / overlooked BJ'z earlier slanderous reference, and besides, I was just 'taking the piss' (of you) as we say is all, and while I may not be 'Kathy', or a woman of any sort, referring to me by my log in will do just fine.

As to your last question, yes (although in that post where I describe my own IWR experience, or a maybe later one, I did make a sarcastic / joking remark about being left 'speaking doggerel' and that may have put a slant on things I did not intend). So yes, I stayed well within 30ft and had complete resolution. (And as, as far as I am aware, have all the other IWR's I have WITNESSED (capitalized just for the benefit of some others), not 'ran' necessarily. But some I only (would have) heard about later on the grapevine if things 'went wrong MUCH later'. And I say only 'maybe' as never saw a few of the guys again (as while they may have been on 'our ' expedition vessel per se, they were not part of 'our' survey group so to speak. Anyway, a few went back to wherever they came from and..............................I lost track of them, or should I say had no need to keep track of them. But I never heard anything different, and I expect I would have; save for one guy who gave up diving (for at least some time as far as I know) as the whole experience scared the pants of him (and rightly so when its your first time bent). And just to be clear, the IWR's I witnessed, were all way within the 'magic' 30ft limit.

Claro ahora?