An anecdote that's sort of on-topic that people might find thought provoking:
On holiday a few years back I woke up feeling awful, in a pool of sweat, hyperventilating (rapid breathing this time). It was notable for me because despite feeling relaxed, my breathing did not return to normal immediately as it would after waking from a nightmare.
A few hours prior i'd been stupid enough to go Scuba diving, despite not being well enough. I was promised a very gentle shallow dive, basically a paddle around, but instead got dropped into a ripping current and had to exert myself massively for a long time. I would hazard a guess that I'd experienced lactic acidosis and was hyperventilating to compensate for that.
It might've been complicated by gas exchange post-dive, but some time after that experience I was worked up in a myopathy clinic and had a blood lactate test, my levels were the highest the doctor had seen outside of ICU - when I looked it up my blood lactate level was similar to a healthy person post-marathon. I was late for the appointment and had walked quite briskly up a few flights of stairs before the test and felt similar levels of muscle burn to the diving experience...
This is very interesting. When I crash my breathing changes - it is like big gasps followed by very fast and hard expirations. Like someone would breathe if they had just run up a steep hill very fast and were very unfit.
Except I could have just been sitting in bed reading when it comes on, so not necessarily linked to physical exertion.
I tried to look up what might make that happen, and it seems closest to Kussmaul breathing which happens in acidosis.
I've never had my blood pH measured when in that state so I have no idea whether it has anything to do with that.
But t know it's not a lung problem as my lungs are perfectly clear and fine.
It feels to me like a metabolic problem - I feel myself getting gradually more and more exhausted as I continue an activity (not necessarily a physical activity - yesterday it happened after I exhausted myself writing a lab repot), and then suddenly I will collapse and have to lie down, and that heavy breathing pattern will start up.
It goes on very intensely for about 20 minutes or so, during which I just lie there panting and feeling extremely weak.
Then after a while it settles down. I feel like crap afterwards but I can e.g. get up and go get myself a drink, or use the bathroom.
So it's more like acute 'attacks' that I get which are precipitated by feeling a building sense if exhaustion, during relatively mild activity.
Of course this is probably a typical ME 'crash', but I have been wondering whether it could be some kind of acute collapse when blood lactate gets too high after putting strain on a dysfunctional metabolism, and then the heavy breathing and lying down for a while allows for the lactate to be cleared so I recover without e.g. needing to go to hospital like someone in diabetic ketoacidosis would need to.
I might be completely wrong, but I can see how this could happen theoretically if we are experiencing systemic hypoperfusion, impaired systemic oxygen extraction, and relying on anaerobic metabolism more than a healthy person would.
I would imagine this scenario could lead to acute 'attacks' of lactic acidosis which might be cleared with lying down and panting for a while.
