"Undeserved" DCS hits

[Duke Dive Medicine]

Intersting that you mention hydration,when I understand a lot of research shows this plays less of a role than once thought.

There's even some recent research out of France (IIRC) that says that exercising to dehydration a short time before a dive, followed by fluid replacement immediately before the dive, decreases venous bubbles. That said, dehydration is still considered by most to be a risk factor for DCS, and since it comes up so often on SB I tossed it in, more as a hypothetical than an actual example. My point was that a healthy diver in good physical condition with no known risk factors for DCS who doesn't make any decompression mistakes can still get DCS.

 

[karstdvr]

My point was that a healthy diver in good physical condition with no known risk factors for DCS who doesn't make any decompression mistakes can still get DCS.

I agree with your statement. The only reason I bring up the hydration comment is that I have heard from 3 seperate DAN physicians who all commented that hydration level is not as critical as once thought from some research. In the past the "unearned" hit would be blamed on dehydration,probably for the sake it is the easiest factor to blame,but if I am understanding correctly this may not be so. I think this is important,because where a diver would write off a DCS incident as dehydration,they may dig a little deeper for a comorbidity.

 

[The Chairman]

I agree with your statement. The only reason I bring up the hydration comment is that

Hydration still plays a role, and most people see all of those as ways to make yourself "bullet proof" against DCS. Look at Jim Fixx. The man with incredible cardio vascular health dies of a heart attack! WHODATHUNK! The point is that not all DCS events can be explained. They just can't. The good news is that DCS is still incredibly rare. Obviously, we must be doing something right.

 

[rjack321]

It's not that we don't know the rules... it seems that the ones we know are good to know and in actuality, very, very few peeps get DCS diving within tables and PDCs. What we don't understand are all the mitigating factors.

Maybe in the recreational population, amongst deco divers the incidence seems dramatically higher. There was a poll somewhere (TDS?) and a fairly high numbers of responding tech divers had been bent at least once (25%?). Much higher than the 1 in 12,000-ish rate amongst recreational divers.

I'm sure it wasn't statistically valid and the denominator is unknown. But still a much higher frequency than a comparable recreational diver poll.

 

[Chatterton]

This is exactly my point.

"I got bent following my Uber Sophisticated Dive Computer, but it was not my fault. My hit was totally unexplained, unearned, undeserved, and not my fault. I think Jesus, Allah, and Buddah wanted me bent? It was astrology!"

It is as simple as this, if you get bent it is because of one thing, and one thing only!! YOU DID NOT DECOMPRESS LONG ENOUGH FOR THE DIVE YOU MADE!! This is not rocket surgery.

In this case, you are obviously diving beyond your experience, education, knowledge, and capabilities. Of course you don't know why you got bent, or you would have done something to unbend yourself in the water???

If you don't know how to get back to the surface safely, then don't make the dive, Jackass. You can invent new politically correct terms all day long, but the idea that if you get bent it is not your fault, is total BS, baring a medical condition like a PFO.


Cheers

JC

I disagree with the position that everyone who gets DCS "deserved" to get it through some oversight, inaction, or inappropriate action. Yes, there are some cases where this is true, and we all have stories about such folks. However, it's entirely possible for a healthy, well-hydrated, well-rested triathlete to get bent on his first dive of a series despite following his computer or tables to a T. Maybe he shunted through his pulmonary circulation, or maybe it was just his day. The fact remains that the risks of DCS go up with depth and bottom time no matter what deco algorithm is used. Gene Hobbs and Keith Gault presented a poster at UHMS last year that demonstrated this using commercially available deco software, and we're working on expanding this research right now. The poster should be ready to go for this year's UHMS conference.

For what it's worth, we also use the term "unexplained" vs. "undeserved" because it takes some of the judgmental tone out of it. I think that one reason many divers don't seek treatment for DCS is the stigma that's attached to it, i.e. you got bent, therefore you must be an idiot. We've found that to be (generally) untrue, and we don't treat DCS like a "stupid" injury, we treat it like an athletic injury, because in the vast majority of divers we see, that's what it is. Hopefully one day we'll have a complete biochemical/biophysical explanation of DCS, but we're not there yet, so it might be best to reserve judgment (and hopefully some education leading to behavior change) for those who really need it.

Best regards,
Eric Hexdall, RN, CHRN
Clinical Director, Duke Dive Medicine

 

[karstdvr]

This is not rocket surgery.

Actually I would contend it is rocket science. The algorithms we follow are based on formulas from theoretical tissue groups that more often come from engineers/mathmetician types. What % of the people on these forums understand the math and theory involved,or do we accept it as the gospel because I did a profile,and didn't have DCS symptoms. I agree in that all DCS cases have a reason,but since decompression is theory,and not a complete basis on physiology,then we have to either accept the risk,including the "I followed the rules and got bent",or quit diving altogether.

 

[ucfdiver]

This is exactly my point.

"I got bent following my Uber Sophisticated Dive Computer, but it was not my fault. My hit was totally unexplained, unearned, undeserved, and not my fault. I think Jesus, Allah, and Buddah wanted me bent? It was astrology!"

It is as simple as this, if you get bent it is because of one thing, and one thing only!! YOU DID NOT DECOMPRESS LONG ENOUGH FOR THE DIVE YOU MADE!! This is not rocket surgery.

In this case, you are obviously diving beyond your experience, education, knowledge, and capabilities. Of course you don't know why you got bent, or you would have done something to unbend yourself in the water???

If you don't know how to get back to the surface safely, then don't make the dive, Jackass. You can invent new politically correct terms all day long, but the idea that if you get bent it is not your fault, is total BS, baring a medical condition like a PFO.


Cheers

JC

Totally disagree. I know of a dive buddy who got bent doing a dive we've done 30+times, including several of those times AFTER the DCS hit with no change in deco (and no DCS symptoms).

 

[LiteHedded]

I'm glad John has decompression all figured out. I wish he'd explain it to the rest of us jackasses.

 

[ucfdiver]

I'm glad John has decompression all figured out. I wish he'd explain it to the rest of us jackasses.

You'll have to sign up for his advanced deep air course to learn that. Can't be giving info like that out for free.

 

[TSandM]

I don't think it's debatable -- if you got symptomatic DCS, you did not do the decompression required for the dive. The problem is that sometimes we don't KNOW how much decompression is required, and obviously, there are times when what is needed is more, or different from what we have successful done before. And no one knows how to predict the dives where this will be true, because we simply do not understand the totality of the process that ends with symptoms. With all due respect to Mr. Chatterton, not all DCS cases are due to stupidity or error, unless you define a failure to take into account unknown factors as an error.