Everything done right......still a hit.....

[ocean4vr]

Again.....I'm absolutely amazed at the number of responses....I want to thank all that have tried to answer the question....Why did it happen?
Here's more info to answer the new questions.
I was 48 years old at the time of the dive. I did not have any alcohol for months before the dive. I was in Florida for the month staying at my parent's house. So there was no stress in travel, etc. I wish I could show all of you the profile that was downloaded from my computer, but I do not have a scanner to do that. My ascent was slow(because I like to enjoy the view as I'm going up). I willsay that the current was strong because when I left the bottom for the free ascent it took me on a sideways ride, but not an upward ride. I was diving off of New Smyrna Beach Florida, water temp. was great, I was not too hot or too cold......just right! Believe me, I'm not fond of cold water. I was not doing anything streuous before, during, or after the dive. I thought it was a pulled muscle because sometimes when I go to sit down on the bench I miss the tank holder and have to reposition myself. Other than that I helped wrap up the line(string with a small weight) which wasn't difficult.
I consider myself in good shape and can dive with the best of them without trouble.
Lisa

 

[DandyDon]

Wow, Lisa - with that additional information, it really sounds like an underserved hit - now called "unexpected." Sounds like you did everything as correctly as possible. I can tell that you're not quitting, so I guess - hydrated more, perhaps with sport drink, starting a day before. Good luck

I have to take a little issue with this...

It's hard to believe that she could have done everything right and still been so seriously hit. Kinda makes me scared to go in the water again.

When I burned my hand on hot iron, I learned to wet my finger and test irons. When I fell off a horse, I got back on before a phobia could set in and learned to saddle & ride better.

 

[Web Monkey]

There has been a observable occurence on these types of postings over the years that I have noticed. Someone post that a diver got a hit following their planned profile.

Immediatley everyone says to themselves.. "Well THEY must have screwed up!" Must have not drank enough water, ascent to fast, sawtooth profile, strenous activity, too lean gas, exp suit too cold, etc etc.

Well, actually, yes. No "screwed up" necessarily, however humans are physical entities and both they and the disolved gasses they contain are subject to the laws of physics.

The fact that someone has DCS means that some combination of physics, their physical condition, environment and biology conspired to make more gas come out of solution faster than they expected.

While the cause of any particular case of DCS may not be obvious or even determinable, something caused it.

Terry

 

[HilaryRN71]

You poor thing...good luck. DAN says 60% of DCS cases do not break the limits of the computer the diver the was following. And i took a class on DCS where the literature states that DCS is often more of a "statistical probability" than an "accident." I like to dive deep and push bottom times and I worry that I will take a hit someday. But it sounds like you have a good plan. Nitrox at the highest concentration for that dive, and if you don't already do them, deep stops at half the max depth for 1.5 minutes (I do 2 minutes). And long 5 minute safetys. (My last true drift dive was to 130 feet and we drifted along at 20 feet for 10 minutes, that is what's nice about drifts) Good luck!!

 

[Cacia]

I am increasing intrigued with the PFO stats. If it is true that 1 in 5 has some degree of this ( I thought I read this somewhere) then 20% of us are susceptible to microbubbles getting shunted from the venous side to the arterial side of our hearts. The implications of that for me was to get it ruled out on an echo. (ultrasound) Please correct me if I am wrong, some MD out there, but my impression is that this is news we can use and that this is a relatively easy thing to rule out. If you are a diver, my opinion is that you should. I am not 100% sure about all this, so take what I say with a grain of salt. I am an RN, understand basic hemodynamics but haven't been in the field for quite a while. The 20% thing got my attention, but like I said, I cannot remember where I read that. I did have a converstation with a cardiac surgeon recently in Palau and he did gave me the impression I was correct.

 

[lilycat]

There has been a observable occurence on these types of postings over the years that I have noticed. Someone post that a diver got a hit following their planned profile.

Immediatley everyone says to themselves.. "Well THEY must have screwed up!" Must have not drank enough water, ascent to fast, sawtooth profile, strenous activity, too lean gas, exp suit too cold, etc etc.

Anyone ever spend a little time at a craps table? The models are pretty good as proven over X times of dives by Y numbers of divers however you are still throwing dice and she might have done it all the way we are trained and yet there is not a glowing red devil in the details to point at and say, "YEP that is it.. I knew it!" That makes you feel all warm and fuzzy about the way you dive because YOU do not do that.

We can try and cut the odds in our favor by hydrating, conservative profiles, staying warm, not drinking coffee, no booze, sleep well, slow ascents, deep stops, longer stops, better mixes, and no strenous activities after diving and perhaps dive for 24 years and never take a hit.. then "Just when you think it is safe to go back into the water".... "Today's the day."

My $100.01 worth.

You're right. Anything can happen and does.

It is also true that most serious accidents include a component of human error as a root cause or as a contributing factor. I think people are try to suss out if there was anything avoidable that could save them or this person next time. The reactions should be expected and welcomed as they might find that someone did something to help things along in a bad direction.

For the original poster: thanks for sharing your experiences and answering people's questions. It helps us all keep safety in mind which helps us to be safer.

 

[MonkSeal]

I am increasing intrigued with the PFO stats. If it is true that 1 in 5 has some degree of this ( I thought I read this somewhere) then 20% of us are susceptible to microbubbles getting shunted from the venous side to the arterial side of our hearts.

AFAIK it's closer to 1/3 i.e. above 30%. Simple echo won't rule it out. PFO has been discussed in this forum several times as well as diagnostic methods. I believe you'll easy find these threads using search feature and "PFO*" (and maybe "diagnose") as a key word(s).

 

[ocean4vr]

Thanks to everyone who has relpied to my question. I have been tested for a PFO, it was an echocardiogram with a bubble study. THe result was negative. I have followed through with all the tests (which were many) and they were all negative. Therefore, I know that something happened to cause the hit. I followed the "rules" the best I knew how and it happened. Guess it was just my time to be hit.
I will continue to dive (taking off about 1 year) and still love every minute of it. The first dive may be a little scarey, but I dive with a great dive crew......I will always love and trust them........"SeaDogDivers" is the best!
If between now and July any other follow up tests show something out of the norm, I will have the sense to stop diving until cleared. My left leg is healing slowly and everyone expects it to be fine.
Thanks again to everyone that has responded.
Lisa

 

[Fred R.]

I thought I would come out of ‘lurker’ mode and share a few thoughts on this subject.

First, there is no such thing as a No-Decompression Dive!

I know everyone is taught that there is such a thing, and it is a misnomer.

What so-called No-Decompression diving is about is diving with a low risk of decompression illness. If one follows the Navy Tables exactly as printed, one assumes an ‘acceptable risk’ of 1.4% chance of decompression illness. For the Navy, and navy divers, this 1.4% chance is perfectly acceptable. Navy divers do not dive in peacetime without a diving officer, medical officer and chamber on site. If Navy divers dive in wartime conditions, a small chance of getting sick is the least of the divers problems.

Recreational divers do not generally consider a 1.4% chance of getting bent to be acceptable. By those numbers, I would find myself in the chamber being treated about once a month, something I do NOT consider ‘acceptable’.

So the recreational training agencies, without any research or real knowledge of the subject sought to make diving ‘safer’ by making the tables more ‘conservative’.

The first thing they did was to shorten dive times. Shortening dive times by between 15-20% did not do that much to make diving ‘safer’, it reduced the observable rate of decompression illness to about .4%, or 4 in a thousand dive events. Once again, not acceptable, in my life, that is still 2 or 3 hits a year.

The next thing they did was add a safety stop, 3-5 minutes at 15 feet. Most divers forget about the second number and just heard or were taught the minimum of 3 minutes at 15 feet.

This brought the accident rate down to about 1 in a thousand dive events, a rate that the dive industry in general thought was acceptable for several years.

But too many people were getting bent, and many of them were angry, claiming they were undeserving of this malady.

To lower the rate of decompression illness even further, the rate of ascent was finally lowered from 60 feet a minute, to 30 or 40 feet a minute. This brought the accident rate down to somewhere around 1 in 10,000 events.

It is all about risk groups, if you follow the most conservative of the common profiles, and they are the ones programmed into your computer, you are at risk for decompression illness, albeit a very low risk. The ‘undeserved’ hit, may be merely the odds catching up to you.

You do not have to live with these odds, they are too high in my estimation. (1 in 10,000 is significant in my life at least)

The dive tables were originally meant for military and commercial divers. There is a very strong risk-reward tradeoff at work here. Recreational diving my not have the same criterion. No one is responsible for paying for your treatment but you, the recreational diver, and if you have a life changing injury, you probably would rethink the whole ‘was it worth it?’ scenario.

What to do?

There is a tremendous amount of research that shows that it doesn’t really matter how deep you go, or how long you stay (within reasonable limits), what is REALLY critical is how you come up.

H2Andy has the right idea, come up slow and stop often.

The US Navy commissioned a study to make new and safer dive tables. The team of hyperbaric researchers spent years coming up with a new concept, which never was published, the Navy decided not to use it.

What the researchers came up with was a concept they called a parabolic ascent. Simply put, as you near the surface you slow your ascent rate, drastically.

Two years before they reached this conclusion, I was already teaching it in my OW courses and daily in my dive briefings, based on meta-research I had done after a dive buddy got bent on a no-deco dive, with slow ascent and a 3 min stop at 15 feet.

So here is my advice, for recreational diving;
Come up slow, no I mean really slow. 10 feet a minute starts to act like a safety stop.

On dives between 130-100 feet, stop for one minute at half the maximum depth.

On all dives deeper than 25 feet, stop for one full minute at 25 feet.

On all dives, stop at 15 feet for at least 4 full minutes. (these numbers are +- 5 feet)

Will this keep you safe? Maybe not, but I have been doing this since 1990, have done 13,000 dives this way, and been part of 100,000 dive events, all without a SINGLE case of the bends. So I think I am on the right track here.

For what its worth to you…

 

[O2BBubbleFree]

I thought I would come out of ‘lurker’ mode and share a few thoughts on this subject.

Hi Fred, and thanks for the historical perspective.

So here is my advice, for recreational diving;
Come up slow, no I mean really slow. 10 feet a minute starts to act like a safety stop.

On dives between 130-100 feet, stop for one minute at half the maximum depth.

On all dives deeper than 25 feet, stop for one full minute at 25 feet.

On all dives, stop at 15 feet for at least 4 full minutes. (these numbers are +- 5 feet)

Will this keep you safe? Maybe not,

If you’ve been lurking here long enough, you know that your approach is similar to ascent profiles discussed here regularly.

but I have been doing this since 1990, have done 13,000 dives this way, and been part of 100,000 dive events, all without a SINGLE case of the bends. So I think I am on the right track here.

For what its worth to you…

So, 15 years times 365 days / year is 5475 days. 13,000 dives in 5475 days is about 5.5 dives per day, right?. You are pushing the envelope!