Rebreather Went out of breath at the end of a dive with on a CCR

[MiddlePilot]

Oh, and feel better soon!

Thanks.

I am not too sure tbh now of the exact order of events, I just know that something didn't feel the same at the start of the ascent but it was not feeling urgent.

I guess an IPE would mean that it would be the end of my CC diving? Do you know if physicians will be able to diagnose the exact root cause?

You are right, I should have called DAN. I think because I felt better by the time we unloaded it did not feel urgent.

 

[cerich]

Thanks.

I am not too sure tbh now of the exact order of events, I just know that something didn't feel the same at the start of the ascent but it was not feeling urgent.

I guess an IPE would mean that it would be the end of my CC diving? Do you know if physicians will be able to diagnose the exact root cause?

You are right, I should have called DAN. I think because I felt better by the time we unloaded it did not feel urgent.

If it was IPE, I know some that have continued to dive after having, some with more conservative approaches and some not. I can think of 2 that choose the "not more conservative approach" that ended as poorly as is possible.

To if a doc can determine for 100% sure, I am not sure. I suspect that they can do scans and see if you have it still going on or markers of. But seriously, that is a question for a diving doc, maybe a respiratory specialist, other than those, most docs are gonna be using their knowledge of physiology and medicine along with reading to do a diagnosis and it isn't exactly common. To know "root cause" I doubt it actually, nobody is even 100% sure the cause anyhow from my reading.


You need to talk with an actual diving doc, do own reading and make own risk/reward analysis and make some decisions my friend. DPV's are also your friend with CCR diving..just saying (less work on you, but even still, physics of breathing a CCR and WOB depending on trim, counter lung position etc all still apply)

 

[Mod63]

yeah, don't disagree, the only thing that leans me to IPE is that it came on at depth on the dive in question, if came on during deco I would lean there. That said, as I said above, I am pretty sure (anecdotally and based off my non doctor understanding) that "mild" POT likely makes one more susceptible to IPE, and I am not alone in that "guess" and many of the others guessing have MD or Phd in a related field behind their name, not MBA and just decades doing this. LOL

Purely anecdoctical here as well: At the height of my problems I started coughing around 40-45mins into the dive when running at 1.3 ppO2. As the OP stated he is asthmatic his lungs might be more susceptic to PTO.

 

[justinthedeeps]

I would indeed suspect some IPO/IPE caused by negative static lung loads during the dive?
Possibly aggravated by abundant diving or other factors?
Was it a fresh sorb canister, properly packed and installed etc? Not overpacked?

Good to pay close attention to signs of "difficult breathing."
I've minorly experienced elevated work of breathing for various reasons:
- exertion/pace
- insufficient loop volume
- maxed out loop volume
- ADV too stiff (adjust, or manually add dil)
- sorb got wet
- sorb overpacked
- poor body orientation

A problem could begin upon entering the water and/or during descent, wherein multiple above factors can come into play. On a longer descent, some of these could increase work of breathing to the point where someone susceptible to IPO/IPE is at risk.

Speaking from experience, faffing about on the surface and then chasing your buddy/leader down a long, fast descent on CCR can compromise optimal breathing, especially if you are task loaded, distracted, falling behind, or carrying lots of extra gear (multiple BOs, DPVs, cameras etc)

I guess the possibility of adverse reactions to high ppO2 must also be considered, by why only on a deep dive? Has the OP not already done long shallower dives @ 1.3?

 

[cerich]

Purely anecdoctical here as well: At the height of my problems I started coughing around 40-45mins into the dive when running at 1.3 ppO2. As the OP stated he is asthmatic his lungs might be more susceptic to PTO.

Yeah, he said similar to asthma, and it seems a logical thing that only someone that has had asthma would describe it like that. I would be more likely to say "my big brother sitting on my chest" because never had asthma, has big brother.

For sure, PTO/POT and IPE can present pretty darn close to each other, and the conditions to suspect either one also sure have overlap.

 

[rjack321]

Yeah, he said similar to asthma, and it seems a logical thing that only someone that has had asthma would describe it like that. I would be more likely to say "my big brother sitting on my chest" because never had asthma, has big brother.

For sure, PTO/POT and IPE can present pretty darn close to each other, and the conditions to suspect either one also sure have overlap.

I seriously doubt this long after the dive anyone will be able to figure out if the airways were constricting due to asthma, or they were filling with fluid due to IPE, or a little bit of both.

@Mod63 have you ever had exercise induced asthma before? Or had an asthma attack on a dive before? Is your asthma normally very well controlled?

(edited) Sorry @MiddlePilot these questions were for you. Hope you're feeling better and have some answers

 

[Mod63]

have you ever had exercise induced asthma before? Or had an asthma attack on a dive before? Is your asthma normally very well controlled?

Hi, not an asthmatic at all, passed all my lung exams with flying colours . It turned out that the medication I was taking for my psiorasis was the culprit. Stopped taking it and am back to normal since. For a while I was limiting my self to "rec" dives where I could live with 0.7 ppO2, which I easily tolerated.

 

[cerich]

Hi, not an asthmatic at all, passed all my lung exams with flying colours . It turned out that the medication I was taking for my psiorasis was the culprit. Stopped taking it and am back to normal since. For a while I was limiting my self to "rec" dives where I could live with 0.7 ppO2, which I easily tolerated.

Any chance you could say you are so that those of us reading this are better able to convince ourselves it can never happen to us?

Sarcasm aside, sorry you are having to go thru all of this and thanks for sharing, it could for sure help some other diver(s) who may find themselves in same situation.

 

[MiddlePilot]

Hi, not an asthmatic at all, passed all my lung exams with flying colours . It turned out that the medication I was taking for my psiorasis was the culprit. Stopped taking it and am back to normal since. For a while I was limiting my self to "rec" dives where I could live with 0.7 ppO2, which I easily tolerated.

What was the medication out of curiosity?

How did you figure out it was the culprit?

I took some Ketotifen the day before, an asthma preventer.

 

[Mod63]

I was on Apremilast at that time for around 6 months. Between my skin doctor, Celgene and my diving physician we decided to get off Apremilast. After that the coughing fits became less and less. In the meantime coughing has been added to the list of side effects.