Simon Mitchell - Should divers treat DCS in-water?

[johndiver999]

I had a buddy a few weeks ago, come up from a dive and say he was bent in shoulder. Three dives in 130 ft on 34% no watch, no computer, maybe 20 minutes each dive on the bottom and apparently little or no "safety" stop. Jumped back in within 4-5 minutes, went down to 25 feet or so, on 34% for maybe 12-15 minutes and got back on the boat and said he was all better. Said shoulder was a little sore a few hours later.

I myself had an incident maybe 8 weeks ago after two dives in 70-80 feet that were close to the NDL limit and did a decent safety/deco stop. Got on the boat and had very weird pain in center of back. I did not really think I was bent because the pain didn't seem like it was in the right place and the dives were not unusual and did not violate computer, but I grabbed another tank of 36% and shot down. Time on surface less than 5 minutes.

I was completely amazed, at 35 feet, all pain INSTANTLY went away. I went down to around 38 feet, hung out for 7-8 minutes, took another 10 minutes to come up to 15, and got out a few minutes later and was COMPLETELY fine! Not even tired and zero pain. Went in, had a picnic, went snorkeling a few hours later, but stayed shallow. I am beginning to think that heading back down ASAP, makes a lot of sense in some situations.

 

[Boarderguy]

I had a buddy a few weeks ago, come up from a dive and say he was bent in shoulder. Three dives in 130 ft on 34% no watch, no computer, maybe 20 minutes each dive on the bottom and apparently little or no "safety" stop. Jumped back in within 4-5 minutes, went down to 25 feet or so, on 34% for maybe 12-15 minutes and got back on the boat and said he was all better. Said shoulder was a little sore a few hours later.

I myself had an incident maybe 8 weeks ago after two dives in 70-80 feet that were close to the NDL limit and did a decent safety/deco stop. Got on the boat and had very weird pain in center of back. I did not really think I was bent because the pain didn't seem like it was in the right place and the dives were not unusual and did not violate computer, but I grabbed another tank of 36% and shot down. Time on surface less than 5 minutes.

I was completely amazed, at 35 feet, all pain INSTANTLY went away. I went down to around 38 feet, hung out for 7-8 minutes, took another 10 minutes to come up to 15, and got out a few minutes later and was COMPLETELY fine! Not even tired and zero pain. Went in, had a picnic, went snorkeling a few hours later, but stayed shallow. I am beginning to think that heading back down ASAP, makes a lot of sense in some situations.

This is exactly why I'm planning to make my old voodoo AL tanks into O2 tanks I'll keep in the truck. Get them filled with 50% or 100% if I can get it and only use them if me or someone in with needs it. Lots of piece of mind in having it there.

 

[NYCrecdiver]

Nice one! Thanks for sharing.

 

[boulderjohn]

I had a buddy a few weeks ago, come up from a dive and say he was bent in shoulder. Three dives in 130 ft on 34% no watch, no computer, maybe 20 minutes each dive on the bottom and apparently little or no "safety" stop. Jumped back in within 4-5 minutes, went down to 25 feet or so, on 34% for maybe 12-15 minutes and got back on the boat and said he was all better. Said shoulder was a little sore a few hours later.

I myself had an incident maybe 8 weeks ago after two dives in 70-80 feet that were close to the NDL limit and did a decent safety/deco stop. Got on the boat and had very weird pain in center of back. I did not really think I was bent because the pain didn't seem like it was in the right place and the dives were not unusual and did not violate computer, but I grabbed another tank of 36% and shot down. Time on surface less than 5 minutes.

I was completely amazed, at 35 feet, all pain INSTANTLY went away. I went down to around 38 feet, hung out for 7-8 minutes, took another 10 minutes to come up to 15, and got out a few minutes later and was COMPLETELY fine! Not even tired and zero pain. Went in, had a picnic, went snorkeling a few hours later, but stayed shallow. I am beginning to think that heading back down ASAP, makes a lot of sense in some situations.

Although it was not exactly clear in the presentation, this is a range of IWR that I don't think was covered: The diver surfaces and feels minor symptoms right away and is not remotely debilitated. I know of more than one such instance of the diver going back for IWR, and in each case, symptoms were resolved. The problem is that in these cases, the only people who know about it are the people who did it, so it is not possible to have any kind of scientific study.

While I know of several such cases, I have only been present for one. In that case, the dive team surfaced after a nearly 2-hour decompression dive, and one began to feel shoulder pain during the final ascent to the surface. On the surface, they decided to go back down for IWR. The pain resolved before they got to 20 feet. They both breathed from their O2 deco bottles for about 20-25 minutes or so. They decided to give the surface another try, with the understanding that they would go to the nearby hospital if it was not resolved. (That hospital was still about 400 miles from a chamber.)

Back on the surface, the one who had experienced the pain felt fine, but he breathed O2 there for a couple hours. He had no more problems.

In those cases, I do not believe it is wise to go down alone. Symptoms can make a sudden turn for the worst, and it is good to have a buddy there if they do.

 

[NYCrecdiver]

This particular guy was back diving the next day. He'd been bent several times before.

After being bent several times before, does he consider changing his DC conservatism settings?

 

[Bigbella]

When I was in Baja, in the late 1980s and early 1990s, a loose form of IWR had been fairly commonplace among a few mad-dog spear-fishermen that I knew and some crazies who captured tiny fish for the aquarium trade, near La Paz — those who would dive ridiculous profiles, if they could even be called that -- without computers or even tables; with little to no training in many cases; and whatever ersatz "IWR" was performed, was certainly done on air, usually via some ramshackle hookah setup, since O2, outside of a medical environment, was unattainable; and recreational nitrox use was all but unheard of, back then.

I ran into one of those guys, some years later, at a Posada, whom, I had noticed, had developed a very nasty limp, and asked, through clenched teeth, whether it had been DCS.

"No," he said, "I got clipped by an [Isuzu] Amigo, broke a leg in two places, and it was poorly set -- still dive . . ."

 

[100days-a-year]

After being bent several times before, does he consider changing his DC conservatism settings?

Never saw on of those on an ORCA EDGE, Marathon or Skinny Dipper.
Guy has been spearfishing probably 50 years commercially and has broken quite a few bones skateboarding, he is an outlier who will likely outlive Keith Richards.

 

[Dr Simon Mitchell]

Hello,

Thanks for the positive comments. I was recovering from a very nasty (non-covid) upper respiratory tract infection when I gave that talk. My voice was not very serviceable!! That presentation was at the Diving Talks meeting in Portugal. It was an excellent event and is running again in October this year. David Doolette and I are both speaking.

For anyone interested I have attached the two papers that were cited in that talk - the one by David and I specifically about in-water recompression may be of particular interest.

Regarding John's comment about chambers. In theory, yes, a good idea. The practical reality is a little trickier. Chambers used sporadically in remote locations are difficult and expensive to maintain. They may not be safe and often fail due to technical problems. Also, they only work when there is someone available who is trained to operate them. That means establishing a roster of trained individuals - another logistic and financial challenge. Trust me when I tell you that as someone who is often contacted for advice about treating divers in remote locations these are very real considerations.

Simon

 

[johndiver999]

This is exactly why I'm planning to make my old voodoo AL tanks into O2 tanks I'll keep in the truck. Get them filled with 50% or 100% if I can get it and only use them if me or someone in with needs it. Lots of piece of mind in having it there.

I try to always have my personal 30 cuft tank of oxygen on the boat. I got bent another time several years ago and had the skin on one leg go completely numb. Since it was a charter dive, there was no way they were going to let me go back down, so I just breathed oxygen on the way in. In 20 minutes of pure oxygen, all symptoms were completely resolved. I'm 100% convinced that incident was DCS, but I had not violated my computer on that day as well. I sought no medical consultation or further treatment afterward.

If you are bringing oxygen on a boat, you need to be super careful about marking it as such, Someone might grab it when you are diving and not carefully inspect it. I prefer to have the oxygen in "weird" tanks.

A 72 steel, holds a good bit of oxygen and is lighter and smaller than an 80 cuft tank and might stand out more to the uninformed.