O2 convulsion question

[diverrick]

After reading a couple of threads about Oxtox, it got me thinking again about what would I do if my partner was convulsing at depth, I had it right BTW, I wanted make sure I wasn't missing something important, but that got me to thinking, how long would a "typical" oxtox convulsion be expected to last? Are we talking moments, minutes, or longer? if the affected person came back from his seizure, and was concious, and a ascent was started, could it occur again at a lesser depth? As for me and my wife, we never ever even get close to 1.4 let alone anything higher. My wife prefers to dive air tables, with Nitrox, I do use the Nitrox tables, but seeing as I dive with her, it really doesn't make a difference which one I am using as her profile is the most restrictive, for both of us.

 

[beche de mer]

My understanding is that the seizure would last for moments, since as soon as the seizure begins, breathing ceases. (And shortly thereafter, drowning commences). With the cessation of breathing pO2 rapdily falls.

As for using air tables while diving nitrox, while this is a good idea, it has no relevance to oxygen toxicity. It is essential that you are aware of the maximum depth you can go to with your particular mix.

 

[CuriousMe]

My understanding is that the seizure would last for moments, since as soon as the seizure begins, breathing ceases. (And shortly thereafter, drowning commences). With the cessation of breathing pO2 rapdily falls.

As for using air tables while diving nitrox, while this is a good idea, it has no relevance to oxygen toxicity. It is essential that you are aware of the maximum depth you can go to with your particular mix.

I'm confused I guess....why would breathing cease immediately? If someone were to have a seizure on land, do they stop breathing? Sorry for the basic question....don't know a lot about seizures.

My understanding was that generally drowning during an OxTox induced seizure was due to the fact that the regulator would likely come out of your mouth and since you are still breathing you're now breathing water.

If you saw it happen to your buddy, wouldn't the right thing be to keep the reg in their mouth and get them higher in the water colum?

Peace,
Cathie

 

[diverrick]

your buddy is not breathing. Ascending while he/she is not breathing, would be inviting serious damage to the lungs and other issues due to the expanding gases, on ascent. If they were breathing, then a slow ascent would be advisable I would think.
As for knowing your MODS, we alway check that before the dive, and never exceed it, we like to stay within recreational OW depths (60 Ft) for the most part, and never go over the air tables for dive times. That being said, we have gone beyond OW limits, but it was intentional, and we make sure not to blow our MODS at all costs. I want nothing to do with Oxtox.

 

[jagfish]

Hmmm
I have a spare moment, so I will add my non-professoin opinion, here, waiting for those more informed.

First, my understanding the ath TDI advanced Nitrox is an excelent course and teaches more about this type of situation as well as many hter aspects of no\itrox use that go beyond a basic course.

My understadign is that while a diver is expereincing convulsions, various muclse in their body are restricted, impedign the flow of air into and out of the lungs. To move someone upwards at that time would to risk air expansion injury. HOwever, once the convulsion has passed, teh muscles are once agai in thier natural state, and they can be moved. If they are unconsicous, as they move upward, the air will natrually be vented from lungs as they ascend. If the regulator was still in thier mouth, I believe they will begin to breath on thier own. All the tests were done by the NAVY, and since the test subjects were in chambers or bell suits, they did not get water in thier lungs, and resumed breathing normally afterwards.

If the regulator was not in their mouth, you will essentially be bringing up a drowning victim, just like in any other rescue situation.

JAG