Sorry, should have been more specific about what I was asking. I wasn't asking for anything that he told you in confidence, nor would I ask.
Your post made me intrigued as to the after effects(physilogically) of such a dive. I never really thought about it because I never knew people really suffered long term issues after completing such a dive. That is until you made your post. Thanks for the insight as not too people know such a diver.
There are other way more qualified (
@Duke Dive Medicine amongst many others here) but my understanding, based on the conversations with Ahmed and Nuno's experiences etc:
We gloss over the whole pressure issue in OW training ("only the air spaces matter, the liquids in your body don't compress, don't worry about it..."). Once you get to serious depths though, those effects can't be ignored. There are pressure differentials due to different compressibility indexes in your body (think bone vs blood vs fat etc) and these can play a role in how your blood circulates and then to how you offgas later on.
This is NOT necessarily what happened to Ahmed but one of the concerns his doctors had going in: If you have ANY constrictions on you, which change during the dive (think shifting wetsuit, moving straps on harness, BP shift etc) then there can be pockets of tissue which may ongas differently and then later offgas differently. Lets say your BP restricted capillary and smaller vessel flow in the spinal region during the offgas phase with the most likelihood of bubbling. In that case, it is possible that a "trapped" bubble will form in those vessels, and that bubble may or may not be released at some time. If the vessels are blocked, then there will be tissue damage due to oxygen deprivation, depending on how long it is blocked. Where this tissue is and the size of the affected area will affect what, if any, symptoms you may present with.
Hypothetical: Tissue alongside the spine is cut off from blood flow, there is also a mechanical force on the nerves in the area due to the actual bubble. You then spend 14-15 hours with no blood flow to that area during deco. That will not pass without some long term effects. Meanwhile, your deco passes and the bubble reduces back to negligible size and thus no "classic" DCS symptoms. However, you now have long term nerve damage in a (fairly random) part of your body.
At 332.35 meters, his body shaking, aware that his goal was just over 15 meters away, aware of the almost 14 hours still ahead of him, Gabr grabbed the depth tag on the rope and turned back
Both Nuno and Ahmed had the same plan going in: at the very first sign of HPNS (or any unplanned event), they were done. Nuno had his hand reached out for the next tag and he saw it twitch, he ascended immediately. Ahmed had exactly the same plan and did the same thing, it was a little easier for him since his next tag was clearly out of reach, IIRC Nuno was about a metre or two from his next one. That takes an INSANE amount of discipline, which is why Nuno and Ahmed are still around to talk about it after the kind of dives they have done, even excluding the record dives.
To the incident at hand, I do not believe either of them would have continued with the attempt if ANY planned element of the dive was missing/inoperative. That would include the weather and definitely a missing deep support diver.
