Do you think this could be DCS?

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Miyaru

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...
What I think happened:
Until posting this I had forgotten about the predive drama that we had before dive 1. Our dive site was a completely exposed reef approximately 10NM offshore. We first got dropped off the boat in the wrong spot, and my boatman tried to tow us to the site. I have done this plenty of times when freediving, but never before on scuba. The extra drag from the scuba gear made holding on a seriously strenuous effort and ultimately made it impossible for the boat to turn us towards the reef. We got back on the boat and motored to the site and I didn't think anything of it at the time.

Looking back I think I was just too preoccupied to notice that my shoulders were giving me grief and that I had probably pulled some muscles while being towed behind the boat. Years ago I had shoulder issues from snowboarding that had accompanying fatigue, not sure how that works but I think that is what is going on here.

It has been a good exercise thinking my way through this and I am now far more prepared in the event that myself or my future dive buddy were to get DCS. I now have the NZ dive emergency # in my phone and I think I will be less hesitant to call it if I suspect any problems.
This!

Two years ago I lifted 8 tanks from my car at the compressor station and yanked out steel doubles since they were heavy. That sealed my fate even before we got into the water that same afternoon, 4 hours later for a dive to 64m/210ft.

After recompression treatment and an MRI scan of my shoulder 3 weeks later, the doctors could see that the damage occurred in the muscle tissue (and fortunately nowhere near the bones). Thanks to posting my story here, I started considering everything action before the dive. And that's when it struck me....unloading tanks, even hours before the dive. That fact also made the doctors look closer at the muscle tissue and the answer was there.

Now this was a dive beyond the recreational boundaries, but a longer dive to only half the depth would have resulted in the same outcome.
Crossing the NDL is a gray area, since both tables and computers follow a pre-calculated model, based on an average diver. Many divers cross the NDL in real life while their computer says they're diving within limits. Others cross the NDL according to the computer while their body is still within the NDL.

Crossing the NDL is not like a switch from fun to drama. Knowledge and experience can turn fear into confidence, so it might be very interesting for you to explore that NDL border with an instructor during a course. From your description, you're ascending when you're getting close to that number on your computer. So you are already touching the border....
 

chillyinCanada

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Hi again

Thanks for all the replies. There is some interesting information in there. A few points and questions have been raised and I would like to respond to them. I am feeling a little foolish because I think I have figured out what happened and it ain't DCS. I'll save that for the end.

Why I didn't do something straight away:
I didn't think it was that bad and didn't link it to DCS, I just thought that I must have over exerted myself. My life has been pretty full-on lately.

On computer vs tables:
I recently converted from tables to a computer and one of the first things I did when I bought the computer was comparing it to the standard PADI tables. On a square profile dive to 30M the tables had 25% more NDL time (20m vs 16min). I am convinced that if I calculated this day's dives on tables as multi-level dives that it would have been fine.

On dive aggression:
I have always been paranoid about getting the bends and so I keep a close eye on my NDL's and depth. On the 1st dive, I hung around the 20m mark until I had 10 min to NDL at which stage I showed this to my dive buddy and we began slowly ascending to the top of the reef at 10m. Once we were there the NDL got quite big and I was having a good look around. Unfortunately, my dive buddy was too cold so we ascended to our safety stop shortly after and finished the dive from there with plenty of gas and NDL. The second dive was similar (a bit less NDL at depth at the time of ascent, maybe 8 min) and was thumbed for the same reason again.

What I think happened:
Until posting this I had forgotten about the predive drama that we had before dive 1. Our dive site was a completely exposed reef approximately 10NM offshore. We first got dropped off the boat in the wrong spot, and my boatman tried to tow us to the site. I have done this plenty of times when freediving, but never before on scuba. The extra drag from the scuba gear made holding on a seriously strenuous effort and ultimately made it impossible for the boat to turn us towards the reef. We got back on the boat and motored to the site and I didn't think anything of it at the time.

Looking back I think I was just too preoccupied to notice that my shoulders were giving me grief and that I had probably pulled some muscles while being towed behind the boat. Years ago I had shoulder issues from snowboarding that had accompanying fatigue, not sure how that works but I think that is what is going on here.

It has been a good exercise thinking my way through this and I am now far more prepared in the event that myself or my future dive buddy were to get DCS. I now have the NZ dive emergency # in my phone and I think I will be less hesitant to call it if I suspect any problems.

IMNSHO, regardless that you have discovered the original source of your shoulders' injuries and whilst I agree that is very likely the cause, you still need to get a checkup. Your shoulder pain is not the cause of your fatigue.

Further, you should probably be getting physiotherapy on your shoulders. Keep using them but carefully. You don't want to end up with frozen shoulder syndrome.
 

tursiops

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I am convinced that if I calculated this day's dives on tables as multi-level dives that it would have been fine.
Except that the tables are not designed for use on a multi-level dive. People think they have figured out how to do it, but in general they are wrong. Lots of threads on this.
 

tursiops

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Obviously this is not how the tables and computers are suppose to be used. Nevertheless, we have to remember that tables and computers are just tools for risk management,
If you are going to ignore how tables and computers are meant to be used, why don't you just ignore them totally and jump in until your air runs out? On the other hand, maybe you are smarter than the people who designed and verified the tables and computers. [/SARCASM]

I really don't understand folks who think their own experience and beliefs and opinions outweigh strongly validated evidence and facts.
 

boulderjohn

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I started getting elbow pain after a decompression dive. I wasn't sure what caused it, so I ignored it, of course. It got worse and worse after subsequent dives, but I finally figured out what had caused it. My feet were very tight in the foot pocket of my fins, and pulling them off in the water so I could climb the ladder had caused an injury similar to tennis elbow. I started spraying the inside of my fins with a silicone spray and they were suddenly easy to remove--sometimes too easy :).

Here's my point: that silly injury took more than 6 months of rest for the pain to go away. Yes, you can get injuries doing activities like this, and yes, they can last a long time.
 

Ucarkus

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If you are going to ignore how tables and computers are meant to be used, why don't you just ignore them totally and jump in until your air runs out? On the other hand, maybe you are smarter than the people who designed and verified the tables and computers. [/SARCASM]

I really don't understand folks who think their own experience and beliefs and opinions outweigh strongly validated evidence and facts.

Not sure why you got fired up,that statement was actually direct quote from DAN - Please watch starting 6:30.
 

tursiops

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Not sure why you got fired up,that statement was actually direct quote from DAN - Please watch starting 6:30.
Context is everything.
 

scubadada

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...On dive aggression:
I have always been paranoid about getting the bends and so I keep a close eye on my NDL's and depth. On the 1st dive, I hung around the 20m mark until I had 10 min to NDL at which stage I showed this to my dive buddy and we began slowly ascending to the top of the reef at 10m. Once we were there the NDL got quite big and I was having a good look around. Unfortunately, my dive buddy was too cold so we ascended to our safety stop shortly after and finished the dive from there with plenty of gas and NDL. The second dive was similar (a bit less NDL at depth at the time of ascent, maybe 8 min) and was thumbed for the same reason again...

Fortunately, we do not have to debate tables vs. computers. @Bazzathemammoth was using a computer running a conservative deco algorithm, Mares RGBM, and had 10 and 8 min of NDL time left when he began his ascents. It appears the ascents were leisurely, with time in shallower water, thus the avg depths he listed previously.

So, these were not particularly aggressive dives
 

Ucarkus

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Fortunately, we do not have to debate tables vs. computers. @Bazzathemammoth was using a computer running a conservative deco algorithm, Mares RGBM, and had 10 and 8 min of NDL time left when he began his ascents. It appears the ascents were leisurely, with time in shallower water, thus the avg depths he listed previously.

So, these were not particularly aggressive dives
I gave examples of suunto which uses rgbm as well, depending on user setting, it gives up to 22 minutes less ndl for his average depth. He stated that his mares was set to minimum conservatism. Had he used more conservative setting, which would be more suitable for his personal fitness and diving conditions, this would be probably a decompression dive.
 
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