Young and not bent

[pos-tech]

I am a young man 22 and have been diving forever I am in reasonable good shape.
On a recent trip to CA channel islands I did many repeditave dives over 4 days on the fith dive of the fourth day there was an insidant involving a paniked diver draging me to the surface. That day I had already done 3 dives all to over 120ft (a normal trip for me) and usually a run time of 20-40 min. and teh previous three days I had don 11 dives most following the same profile I dive an oceaic computer and never violate it. On the dive in question I had already been to 135 feet for about 10 min and wass at about 60 feet with over 20 minutes of deco when a diver grabed and decided to "help" me surface in about 30 seconds She had no weight belt a full BC and grabbed me as she passes me from 100 ft. when I realised what was happening I tried to trow her off and started to exhale When I surfaced I towed her to the boat. I did not take o2 because I shoewed no sighns of dcs. am I just very lucky?????????

 

[AquaTec]

Smart move by exhaling the whole way,

I would have taken the O2 if available it can only help

 

[blackwater]

lucky that you were "helped" to the surface, no.

lucky that diving outside the profile didn't lead to DCI, yes.

of course crossing the magic line on the computer from in-profile to out-of-profile isn't a garantee of crossing from no DCI to DCI, only a change in probablilties.

As for the O2, yes it could only help, but it also would start a course of treatment which might require continuation to compleation.

GT

 

[Dr Deco]

Dear pos-tech:

This experience is an example of the “bends/no bends” that many believe exist in dive tables. There is no such line.

“Lucky” can be described in different ways. You might be a DCS-resistant diver (in general) or you might have been resistant on that particular dive. In that case, nature and Nature’s God were with you. If you had been a DCS-prone individual, you would have found that out very quickly. Then what would you have done?

There is a saying in decompression techniques, “When it works, it works well. When it fails, it fails catastrophically.”:boom:

Dr Deco:doctor:

 

[Genesis]

on where you are.

On my own personal boat, if you ask for the O2 bottle, you get it. Its YOUR call. The cost to refill it is only $10 - that's immaterial to ME. The only thing I ask is that if you ask for it you breathe it until its empty; if you think you need it, that's good enough for me.

Now if you have SYMPTOMS of DCS, then the day is over, we're heading in, the USCG is going to get called, you may get medevaced, etc. But if you ask for the O2 bottle and do NOT have symptoms, then its your call - I'm not a doctor nor a hyperbaric physician, and that YOU have chosen to breathe O2 as a prophylactic against a POSSIBLE (but not evident) problem is, all on its own, not one of those 'go to the chamber now' deals. If you want me to call the USCG, or if YOU want to call the USCG, use a cell phone (if we're in range) to call DAN, call the day, etc, then have at it - that's a GOOD idea. If you don't, then again, its YOUR call. You're an adult and its your body - and risk. Until and unless there is an objective reason for an outside person (e.g. ME!) to believe you ARE bent, the decision as to whether or not you are is entirely yours.

If you ask for the O2 bottle on a chartered dive boat then the usual protocol, from my understanding, is that you start a course of action that inevitably calls the day and leads to you being treated as a DCS victim, whether you are or not.

IMHO, and I'm not a doctor, that's counterproductive, in that it will typically cause you NOT to call for the bottle when you MIGHT need it (but have no symptoms). That could hurt you. In the situation posited, where you got dragged to the surface, asking for the O2 bottle is likely the prudent thing to do, but if it causes you be treated as if you have a DCS hit on a charter boat then you'll be dis-incented from doing so UNTIL you have symptoms - which may expose you to an unnecessary hit.

Breathing the O2 bottle on the surface as a conscious, non-symptomatic person, is EXTREMELY unlikely to hurt you. Consider that at 100' with 32% EANx you were just breathing a PO2 of 1.0 - exactly the same thing you're getting from the demand mask on the surface. From my understanding it might even PREVENT a hit that you would otherwise take. If you have reason to believe that you have violated a safe dive profile when you're on my boat, I WANT you to grab that bottle and empty it, because I'm a whole lot more interested in seeing my friends NOT get bent than playing games with machismo and "oh, I don't want to ruin the day."

Of course as a private, non-commercial person, non-MD and non-dive-"professional", I have a completely different perspective on this - that of a friend and a fellow diver - than someone who has a FORMAL duty of care and a checklist-style set of procedures to follow.

 

[MikeFerrara]

If I'm not mistaken the current DAN reccommendation is to not go on O2 unless there are symptoms. The reasonomg being that the O2 is not likely to prevent a hit (it's too late) but may mask symptoms and delay effective treatment. I am of course just repeating what I have read and not giving medical advice. I always carry O2 and if someone asks for it they will get it. If there is an incident with a student and any doubt exists at all I will call in the calvery. A unnecessary insurance claim is easier to deal with than a pissed off x-diver in a weel chair.

 

[Genesis]

recommend whatever they want. As an adult I will take their recommendations under advisement, but in the end I take my own counsel and live with the consequences of my own decisions.

I'm not a professional in any sense of the word. The fact that I have O2 on my boat, that I am perfectly happy to have any person on board breathe it at their own discretion and request, and the fact that I'm not an MD or otherwise medically qualified is made known to the friends who dive with me.

The recommendations seem to change from time to time. Since with DCS the symptoms ARE the disease, if you prevent them from appearing at all then its definitely not "too late". The potential trap in a position like you have cited, Mike, is that a hit that doesn't occur just looks like a "waste" of a perfectly good O2 bottle. But was it a waste? Or did it prevent the hit?

The point is that there is no way to know which was the case after the fact!

An hour of pure O2 is quite a bit (I carry TWO man/hours on board), and current deco theory is both that (1) all dives are deco dives in truth, and (2) its obvious that your last part of "deco", or desaturation if you prefer, takes place on the surface. If this was not the case we wouldn't have a "no fly" time.

Since people doing INTENTIONAL decompression dives breathe enhanced O2 mixtures (including 100% O2 at shallow depths) for the express purpose of increasing the partial-pressure differential between the N2 in the lungs and bloodstream and that in the tissues, thereby enhancing the rate of diffusion of N2 out of the body, it stands to reason that if a hit is inevitable the sooner the person breathes the pure O2 the more tissue oversaturation will be bled off before symptoms appear and the less severe the hit is likely to be.

I see no logical way in which this can do harm, and plenty in which it can help, including the possibility that a hit that would otherwise be taken would be avoided entirely.

The only possible "gotcha" I can logically deduce would be that if you breathed the entire supply and THEN someone ELSE had a hit, you'd have no more to give THEM. In my case this is highly unlikely as I carry two Jumbo-Ds on board, we are rarely more than an hour out from port, and the Coasties have stations all over the area, including choppers for emergency evacs.

If I know I violated some part of my dive profile that significantly raises my risk of a DCS hit (e.g. a grossly excessive ascent rate, missed deco obligation, etc), I'm grabbing the bottle as soon as I get back on the boat and I'm going to breathe it until its empty.

That's me. Whatever someone ELSE chooses to do is THEIR decision - not mine. Since I'm not a "professional" and have no "duty of care" in these matters on my own private boat, as that boat is not operated as a charter nor am I a "dive professional" in any way, sense or form, I will not presume to tell another conscious and responsive diver what to do or not do. I will, however, allow them to consume the O2 that I have on board if they, in their sole judgement, deem it advisable.

 

[joens]

I'm with genesis all the way .I am a member of DAN but I dont agree with everything they say. Oxygen is a tool for dealing with one of the hazards of diving .If I planned my dive to use O2 at a deco stop or if I think it would be prudent to use it at the surface Its all the same .I will go diving with Genesis any day he will have me aboard.
Chris Joens

 

[Genesis]

and we'll blow bubbles.

Bring your speargun if you like to shoot fish. I don't have an extra...

 

[joens]

sounds like fun . I just might show up one day.
Joens