3 Minute safety stop - required?

[DA Aquamaster]

It is surprising to me that with those immediate reported symptoms and that unfortunate dive profile she was not diagnosed with DCS. I suppose that if one knows the symptoms of DCS and is convinced that one has it you might have "psychosomatic" symptoms but I would think the physician would take the reported symptoms at face value considering the details of the dive.

I think the physician did take into account the details of the dive. 30'-40' for 29 minutes and a rapid ascent after a 7 hour surface interval even after a week of diving, while not ideal, is still not an automatic recipe for disaster. And if the exam results and reported symptoms are not very consistent, concluding DCS is not involved with that profile is not irresponsible.

My spouse had a similar experience with a rapid ascent from 70 ft due to losing control of her bouyancy in a dry suit and panicking. She is already prone to catastrophizing events so she similarly wigged out and convinced herself she was bent despite breathing 02 and having some very fuzzy and inconsistent symptoms. A similar trip to the ER insued and a dive doc similarly concluded that he was not worried about DCS. His conclusion was that the symptoms she was feeling were readily explainable due to her being upset and anxious. Turns out he was right.

Questioning the doctor's judgement in this case is at best just Monday morining arm chair quarterbacking by a bunch of baseball players. Going to the Dr. was prudent if the diver was worried and, having an unbent but worried diver is in my opinion better than having a bent diver who is in denial.

I do a lot of decompression diving and the potential for denial is one I have to keep in mind. Given that I am pushing 40 but still pretend I am 18, I find I have to inventory what hurts pre-dive to keep what hurts post dive in perspective.

Both the US Navy and commercial dive operators routinely bring divers up from their 40 ft stop to the surface and blows the back down to 50 ft in a chamber in under 5 minutes. They do have them breathe pure 02 and there are definite differences here, but the concept of "re-descending" after skipping deco stops is widely practiced.

In water recompression was the formerly recommended technique for a missed deco stop as long as the surface interval was under 5 minutes and the diver was symptom free. In a case like this where the saftey stop was missed on a dive well within the NDL's, the surface interval was very short and the diver was symptom free you could view another descent as being uneccesary but I also don't see the harm in continuing the dive and in some respects think it could even be considered prudent.

Going back to 40 ft for a few minutes and then slowly ascended in stages to the surface makes more sense to me though than just going back to 15 ft. as I don't think that is going to accomplish much. I would prefer to treat the missed saftey stop as a missed deco stop following the old missed deco guidelines. Alternatively, and maybe additionally, I'd do a half hour of pure 02 on the boat. Prevention is a lot cheaper and easier than a chamber ride.

In either case, had it been my boat, I'd have offerred the lady O2 as a precautionary measure if she were concerned about being bent.

 

[Mako Mark]

I have seen anxiety manifest itself into mild DCS like symptoms, through hyperventilation and muscle stress.

Symptoms include Numbness and tingling of the fingers, pain in the joints and dizzyness.

when people get stressed they change their breathing patterns. I have seen the above symptoms on a guy that was too macho to admit he was seasick. We made him breathe into a plastic bag for about three minutes and all symptoms subsided.

However, as Shaka pointed out, every dive is a deco dive. Most dive tables focus on the elimination of dissolved gas, and you dont get DCS from dissolved gas. You get it from gas phase gas.

 

[Addict]

The question that remains is: Is a retroactive safety stop of any value after blowing an ascent?

Yes. That is a good question.

Diving a computer.

It is surprising to me that with those immediate reported symptoms and that unfortunate dive profile she was not diagnosed with DCS

So is it really that serious? Should she have taken some time in the chamber? The tingling and numbness was in the tips of her fingers....

 

[Addict]

Oops, I missed the last 2 comments from DA Aquamaster and cancun mark.

My position was that when you are instructed on ascention rates, and safety stops you are taught on the very very conservative side. Not everyone will react exactly the same to similar situations. She is a 30 year old female in good shape.

Granted - I would much rather be conservative and safe - and will always stay on the more cautious side - but this was an unfortunate occurance.

Looking back, I just don't know what we should have done differently, if anything.

P.S. We did call DAN prior to going to the doc. He recommended that we see the doctor - but I don't think that he was that worried either...

 

[Uncle Pug]

My position was that when you are instructed on ascention rates, and safety stops you are taught on the very very conservative side.

At least what I see most folks doing is far from what I consider very very conservative. Square profiles are not what I would call conservative at all.

On the other hand... stuff happens. When stuff happens is as important as that it happened.

On our last dive in Deception Pass we were shot to the surface from 54' in <10 sec. by an upwelling (a straight line on the Stinger download. ) That was six minutes into the dive. If it had happened at another point in the dive it might not have resulted in the same symptoms: hilarious laughter and shouts of enthusiasm.

 

[DepartureDiver]

Is the 3 minute safety stop required? I thought I had heard that it is a 'recommended' safety stop and that if you hit a Pressure Group that requires a deco stop then it is required -

Am I just delusional?

With PADI's RDP, it is both a CYA procedure as well as a geat idea. The stop is (or was last I knew) required if you dive past 100 feet or you come withing 3 pressure groups of the NDL. It is odd to say that a dive is within the NDL and then a "safety" stop is "required". But if this is what it takes for divers to do safety stops then I am all for it. So you are not delusional, but I would do some more reading here and learn about deep multiple safety stops since the goal is to do your body good.

 

[DepartureDiver]

The question that remains is: Is a retroactive safety stop of any value after blowing an ascent?

I vote that it is. The gas phase separation does not occur instantaneously. When an ascent above your ceiling (even if it is the surface) occurs, there is great value in descending back down to your stop.

 

[opiniongirl]

regarding missing stops, and then returning to them, there is a procedure (how well used, I have absolutely no idea) called the "jesus walk" which allows a diver 1 minute to return to the missed stop if he should blow it.

 

[Curt Bowen]

I would suggest not doing a 3 minute safety stop at 15 feet


What I would suggest doing is 2 minutes at 30 feet and 2 minutes at 15 feet

 

[liberato]

...I would do some more reading here and learn about deep multiple safety stops since the goal is to do your body good.

OK, nice set up for me to recommend your Ascending From A Dive article I just read. Very interesting!