Thoughts on untreated DCS

[Joe_MB]

Hi all

Thanks for your replies. I'll try and answer all your questions. Firstly I have got into contact with DAN and they concur with my Dr that whilst my original symptoms were consistent with DCS, the way that the pain comes and goes is not consistent. I am 27 and physically fit - 186cm tall and 168 pounds, I don't think this is a strain from hauling equipment or getting in and out of the boat. I am also an experienced diver and my ascent rates and buoyancy were well under control. I am heading to the recompression chamber on a nearby island, to have a medical examination by the Dr there, I think that's probably the best way to proceed for now.

Cheers

Joe

 

[DandyDon]

Unlikely that DCS was every involved, but not impossible. I don't think the chamber will help after a week, but the chamber doctor can give you more info. Wishing you the best. Let us know ok.

 

[doctormike]

Calling DAN from day 1 would have been a wonderful idea, but with 500+ dives - who doesn't know that?

Hahaha...! Well, with 500+ dives, I certainly KNEW that, but actually DOING it took some persuasion from my buddies.

Denial isn't just a river in Egypt...

 

[Superlyte27]

Gonna go out on a limb and say, "no chance in hell you are bent".

Well, maybe a 1 in 10,000 chance. But I'm virtually certain it's not DCS. I hope that chamber ride doesn't cost you anything, because it's for nothing.

*edit*
Unless you have a PFO. Then I guess you could have gotten bent if I understand the mechanism correctly.

 

[doctormike]

Unless you have a PFO. Then I guess you could have gotten bent if I understand the mechanism correctly.

Interesting point, and I'll ask TSandM and DDM for their input here...

From what I understand, a PFO will shunt bubbles from the venous circulation to the arterial circulation under circumstances of reversed pressure gradients across the atrial septum. This could result in embolic injury (i.e. arterial gas emboli), which is often a stroke-like condition when the bubbles enter the central nervous system. The other way divers get an AGE (without a PFO) would be pulmonary barotrauma, where the bubbles enter the pulmonary veins and are carried to the left heart and arterial circulation by that path. There is some overlap of symptoms between AGE and type II DCS, and the Navy recommends that AGE and type II DCS be treated the same way, but that's for a different thread.

However, classic DCS the result of bubbles forming in the tissues directly - in the joints, or in my case, in the spinal cord. From my previous discussions with experts on this board, I understand that venous bubbles are relatively rare, only forming in about 10% of cases with a square 60/60 profile. Given the relatively shallow profile posted by the OP, it seems pretty doubtful that venous bubbles would have formed at all, so even if he did have a PFO, it would not be a likely source for DCS (if this even is DCS, which seems doubtful).

One point that is still not clear is whether recompression and/or supplemental oxygen work by making the bubbles in the tissue small enough for them to pass through the capillary circulation to the lungs where they are cleared (and a PFO would have a theoretical role in injury), or by letting the gas go back into solution again (in the tissues, where they are) due to the increased N2 pressure gradient that you get when you breathe less nitrogen and more oxygen.

Good summary article about hyperbaric oxygen: Hyperbaric oxygen: its uses, mechanisms of action and outcomes

 

[Duke Dive Medicine]

Gonna go out on a limb and say, "no chance in hell you are bent".

Well, maybe a 1 in 10,000 chance. But I'm virtually certain it's not DCS. I hope that chamber ride doesn't cost you anything, because it's for nothing.

*edit*
Unless you have a PFO. Then I guess you could have gotten bent if I understand the mechanism correctly.

PFO is not associated with pain-only DCS.

 

[DocVikingo]

Hi Mike,

From my previous discussions with experts on this board, I understand that venous bubbles are relatively rare, only forming in about 10% of cases with a square 60/60 profile. Given the relatively shallow profile posted by the OP, it seems pretty doubtful that venous bubbles would have formed at all, so even if he did have a PFO, it would not be a likely source for DCS (if this even is DCS, which seems doubtful).

Perhaps I’ve misunderstood you, but there is a long, substantial and consistent history of published literature showing that some degree of venous gas phase formation/VGEs are echosonographically demonstrable in virtually any decompression, including ascents from very shallow depths and on short bounce dives. While admittedly the vast majority of this venous activity involves small bubble grades that remain asymptomatic (although their effects over a lifetime of diving are subject to some debate), to the best of my knowledge it is not “relatively rare.” Am I missing something?

The other way divers get an AGE (without a PFO) would be pulmonary barotrauma, where the bubbles enter the pulmonary veins and are carried to the left heart and arterial circulation by that path.

Indeed this is another way to sustain AGE, but it doesn’t exhaust the possibilities. Intrapulmonary anatomical shunts have been reported in healthy humans and widening of the alveolar-to-arterial oxygen gradient with crossover has been reported following mild-to-moderate physical exertion while diving. What think you?

Regards,

Doc

 

[Duke Dive Medicine]

Not to speak for Mike, but he probably meant clinically significant venous bubbles.

 

[Akimbo]

The problem with DCS is that the symptom spectrum overlaps normal aches and pains so much...

I am sure this conundrum has resulted in countless unnecessary chamber rides for commercial and military divers over the years. The tendency is to treat when in doubt, especially since a quick Table 5 has no material financial impact.

… -- and aspirin will relieve pain, no matter what its cause...

Perhaps I am taking this too literally, but is that entirely correct? Was the intent to limit aspirin pain relief to normal aches and pains? There are so many maladies that the popular press claims that aspirin mitigates that I am not sure what to believe.

More importantly, what is the latest thinking on aspirin and DCS? I have heard pros and cons over the last 40 years but never felt I had a good understanding. We always avoided it because it often causes indigestion that can be misinterpreted as an OxTox symptom during chamber treatments.

 

[Duke Dive Medicine]

More importantly, what is the latest thinking on aspirin and DCS? I have heard pros and cons over the last 40 years but never felt I had a good understanding. We always avoided it because it often causes indigestion that can be misinterpreted as an OxTox symptom during chamber treatments.

The evidence is very weak. We don't use it. Sometimes we'll give ibuprofen for residual pain at the end of a treatment once we've determined the diver's response to the treatment.