Thursday, June 30, 2005

Vomiting While Diving

Dr Campbell:

I just saw the quote below on your website while browsing around. I realise that you didn't write it, and it is just someone speculating, but I think the "common sense" approach would be rather dangerous if applied. An alternative method is described which I think is fine, but just seeing the "common sense" approach in print makes me feel very uneasy.

I am a divemaster and although I don't guide a lot, I have had some very novice divers vomit while guiding and know plenty of instructors and guides who have experience of this themselves and with clients (one of them always throws up at the start of every dive, and my wife has thrown up a number of times). The universal approach I have seen - which always seems to work - is to keep the regulator in while vomiting and maintain depth (airway closed; and managing a controlled ascent while retching seems unlikely anyway). Once the vomiting has stopped, you can switch to another regulator and make an ascent. When guiding someone, I face them, make eye contact, hold a BC strap or shoulder for reassurance, and place my hand lightly on their regulator (avoiding the purge), letting my fingertips extend up on to their mask so that they are comforted by seeing that I am "holding their regulator in". If someone is looking unwell on the boat, I brief them for this procedure, and I haven't had any complaints yet. Vomiting while diving happens a lot (because people get seasick a lot and tend to dive while on overseas holidays) and I haven't seen it being a big issue - people seem to be more nervous before than after.

Perhaps a doctor's view of things is coloured by dealing with patients who are incapacitated in some way (either by illnes or by being on their back with a mouthful of medical or dental equipment) and whose reflexes are therefore not working at their best. Most people seem to
(re-?)acquire good airway control very quickly when they start diving, regulators seem to clear themselves of vomit very well, and I have never had or heard of a problem with this approach. People are presumably "designed" to throw up and then resume breathing, we are in a good posture to do this when diving, and a regulator in the mouth doesn't seem to complicate things. However I once tried removing my regulator to cough (just to see what would happen) and I got a nasty shock as the breathing reflex after coughing seems strong and I got a lot of water too far back. I don't think that there is a natural reflex to put something in your mouth in order to breathe and I suspect (but haven't tried it) that a diver might have little or no chance of
getting a regulator back in their mouth (and then purging it of water ...) before they started breathing in after retching. If their breathing is under control, then my experience suggests it will almost certainly do no or little harm to have a regulator in their mouth even if it has some residual vomit in it; if their breathing isn't under control then it is _essential_ that they have a regulator in their mouth, whatever the consequences of that may be. In a worst case scenario that they inhale some vomit and have a coughing fit, then having a regulator in their mouth is probably their best bet. (As a guide, you freak if you ever see a typical customer without their
regulator in their mouth for any reason).

Obviously my opinion doesn't account for much on this - I haven't tried it either way personally except for the cough test, but I would urge you to consider the matter, asking around as necessary, and amend your website in some way - I think any suggestion of removing a regulator to vomit is just dangerous, even if offered speculatively or as "common sense". The suggestion of removing one side of the mouthpiece is just confusing the issue here - even if it worked, the sort of diver who could do that successfully would do it anyway if they were going to. I have oodles of dive experience and if I had to throw up I would do it the simple way, but would make sure my backup regulator was to hand and my buddy was aware of the situation (as step 1 not step 5!).

Best regards,

Simon Richards
www.cave-exploration.com