Gasp!

You know, I didn't even think of this one as an incident, but as time goes by, the more I realize it really WAS one. Or maybe it wasn't...you be the judge.



I was diving LR, probably the second dive of the day, 3rd or 4th day of a week-long trip. We were returning from the Florida Room via the Merry-Go-Round tunnel, right around where the large silt slide comes in from the left (if you're heading out) and there's a busted line up top heading off to god knows where. My buddy and i were taking it slow, checking out side passages and generally enjoying the easy ride out.
I let all the air out of my lungs to negotiate a particularly tight duck under, something I've done uneventfully many times before. Except this time, when I had exhaled as long as I could, cleared the duck under, and attempted to inhale again, I found I couldn't. For a period of maybe asecond or two, I simply could not take a breath. Instead, I had a reaction that I could only relate to what it must be like to try to breath from an empty tank. Very wierd, to say the least.

Thankfully, before I had even a moment to panic (or blackout), I sucked in about as hard as I possibly could and managed to regain my ability to breathe. I stopped for a moment, puzzled about what had just happened, and instinctive checked my pressure gauge, only to find that I was well within my 2nd thirds. I remember feeling a bit parched, so I removed my reg, took a swig of good ole florida spring water, and continued on my merry way, with no more breathing problems, on that or any other subsequent dive.

My question is, what the hell happened, and what the hell caused it? At the time I had assumed it was a simple case of dry mouth (or dry throat, rather), but certainly it could have been something else. A mal-adjusted reg? Tainted gas? Just a freakish suction effect due to the lack of air pressure in my lungs? Anything else? I'd be interested to know if anyone's ever experienced anything like this themselves?