Cbl

[Allan Carr]

Originally Posted by Scuby

One thing did occur to me (doing CBL and AAS in the pool this morning) was that would it be possible to give AV underwater using the same idea as the positive pressure O2 kits (effectially purging into their mouth)? If you could block up the exhaust valve a little bit then there may be a way to give in-water AV just as an aid on the ascent (although obviously the priority would always be to get them to the surface asap). Just a thought anyway, probably a waste of time but seemed like it should be possible to at least try?

David

I have heard of this technique being used to rescue a trapped diver (a bit of wreck fell on him) in an OOA situation while they released him. I believe he survived.

When dive marshalling for deep dives involving deco, I always tried to ensure that the last pair did not go down until the first pair surfaced - subject to an adequate tide window. I have been on a boat where we lost two divers for a while because the skipper was too busy trying to recover an injured diver (he dislocated his kneecap banging it on a rock) and since he was diving in a three, thought it OK to come up on his own and then realised that he couldn't get up the ladder! By the time the skipper had got him on board, the other pair had drifted off and it took us about an hour to find them.

[David Martin]

Originally Posted by Scuby

One thing did occur to me (doing CBL and AAS in the pool this morning) was that would it be possible to give AV underwater using the same idea as the positive pressure O2 kits (effectially purging into their mouth)? If you could block up the exhaust valve a little bit then there may be a way to give in-water AV just as an aid on the ascent (although obviously the priority would always be to get them to the surface asap). Just a thought anyway, probably a waste of time but seemed like it should be possible to at least try?

If they're already unconscious the airway is likely to have relaxed. If they've lost the second stage from their mouth, then what you're going to do at this point is force water into their lungs. You certainly don't want to block the exhaust valve, hit the purge and ascend - you're asking to gve them a burst lung.

GUE teaches a toxing diver lift onTech-1, and AFAIK they are the only people to do so. This is similar to what you're describing. However the difference is that a toxing diver is breathing, and what you're trying to do is maintain an breatheable environment, rather than a water one should they try to take a breath (which they will do as a reflex action at the end of the tox). You're not trying to give AV.

You need to be behind the casualty, and pass your right arm under their right arm and get your hand postioned to press the purge on your long hose reg which you've donated to them (splaying the mouthpiece as required) and to give a full neck extension the whole time. You then maintain neck extension, and gentle positive pressure on the DV throughout the lift. It's significantly more difficult than a normal CBL, and unless you've been shown how to do it and practised it, or have the time to work it out for yourself; I'd say you're likely to do more harm in losing control with the lift, than you would in helping the casualty.

David