O2 convulsion

teddy2005

It's certainly a good topic as it concerns a O2 hit under circumstances which normally should not lead to one. But the specifics of that situation have been addressed now since 2005 (even if remaining mainnly unanswered or without scientifically based explanation).

Your questions are also certainly of interest an go perhaps beyhond the particlar case which is at the origin of this threat and I think they should be examined and discussed within a speficic threat (you could open).

If not everybody reads french, you at least do very well btw...

regards

Rubis

I am shy you know, don't want to attract all the attention by a specific thread

JV's book is excellent ... it would help if it was in english. Very well written and informative. In my opinion one of the very best out there.
Sadly it's in french ...

If I have time later I will open a thread

__________________
CK # 341

rchrds

I'd like to throw in my anecdotal 2c- I had an o2 convulsion at 150 feet in '97. Though I was not CC, There are similarities. Like the original poster- I was aware of symptoms well in advance of the seizure (30-40 seconds) in the form of cheek twitches, something I never have otherwise. I remedied the cause (failure to switch to proper mix, carrying improper mix (o2) in the first place, numerous other procedural errors in the course of a high pressure working dive.) by switching from O2 to trimix at depth. I began an immediate ascent, at first with inflation only, at which time the twitches actually abated. As I swam for the surface, fully anticipating a tox incident, i began kicking, which I believe initiated the seizure sequence, as within 5 seconds of starting to kick, my vision narrowed, and within a few seconds after (and at 30 feet of depth) I blacked out. I was subsequently picked up from the rock bottom at 150 feet by my dive buddies, and returned to the surface prior to my larangiospasm (sp?) relaxing. Once on the surface, I was revived within minutes, with no water in my lungs and flown to the chamber. I made a 30 minute chamber ride after convincing the local docs that there were no dcs symptoms, and was retained for observation overnight. I dove two days later, just to make sure I would not be afraid to get back in the water, and have had no issues since.

Procedurally, I got what I deserved, you can figure the PPo2 of oxygen at 150 feet, and its not good. However, I am still of the opinion that in my case, had I not began kicking, and instead allowed my inflation to take me to the surface, I might have been able to avert the incident. I certainly had enough perceptual awareness during the event to follow that course of action.

Jason