Monoxide Poisoning?

[DiverInAk]

Wow, it's been FOUR years since I've been on this board. Amazing.

Anyway, am asking for a best guess here. If you recognize the conditions I ask that you keep it to yourself. I'm simply looking for rational discussion for my own sake and not the sake of anyone else’s.

Two divers, fit, healthy and well trained enter the water for a cold water dive wearing dry suits and appropriate undergarments for the conditions. They are to perform a rather shallow profile of no 20 meters for 20 minutes and are tended by a messenger line to the surface, water temp around 29F. This is not their first dive like this.

Sometime after over 100' of line is paid out from the surface the shore gets concerned, they could be swimming horizontally. After a few tugs they fail to respond appropriately to signals. The shore begins to pull them up at approx. 1ft per second.

Both divers arrive at the surface unconscious. They cannot be resuscitated. There are signs of embolism. One gauge reads 180' the other stopped at its limit of 200'. Total time submerged is just under 20 minutes.

I'm guessing that both divers were overcome shortly after entering the water, then started a slow descent and the embolism was caused upon ascent which was by pulling them up by the messenger line. To knock out two fit divers I would 'guess' monoxide.

Does any of that sound reasonable to anyone? Are there other things that could render two divers unconscious like that? Other causes to present signs of embolism?

 

[rjack321]

Could have been almost any contaminant, not just CO. Toluene or another narcotic vapor. Or even O2 toxicity.

What are these "signs of embolism" you mention?

If they embolized, they weren't drowned prior to ascent.
because...
If they passed out at depth, their airways would have most likely been relaxed, lungs half full of water and unlikely to embolism.

 

[DiverInAk]

I don't want to get too detailed here, but suffice to say that they were embolized and there were signs at the surface. I really hadn't thought about 'other' gases being present, but you're absolutely right. They do fill their own tanks though have rather stringent procedures, but that doesn't mean they check every fill. I don't 'believe' that they fill from a bank, but I might be wrong on that.

In any case, they felt good enough to descend a few feet, perform an underwater equipment check and then proceed on the dive. I believe they dove with AGA on demand dive masks.

 

[texdiveguy]

Sometime after over 100' of line is paid out from the surface the shore gets concerned, they could be swimming horizontally. After a few tugs they fail to respond appropriately to signals. The shore begins to pull them up at approx. 1ft per second.

??? You stated that after the shore tender played out approx. 100ft. of line and then signeled and got know reply...the tender hauled the divers in.....how then did they descend to a reading of 200ft.?

 

[texdiveguy]

If they embolized, they weren't drowned prior to ascent.
because...
If they passed out at depth, their airways would have most likely been relaxed, lungs half full of water and unlikely to embolism.

If a diver dies at depth regardless of the cause and regardless of the amount of water in the lungs in many cases when the body is brought back to the surface,,,,what appears to be embolism will so distinct signs,,,,gasses expand during the accent and in many cases body fluids/blood will be foamed and present at the mouth/mask etc.. Recovery divers have defined proc. for recovering victims to address this issue. So what was seen at the site may have been a similar natural process,,,only the ME can determine the divers cause of death.

 

[amascuba]

did you have their tanks analyzed?

 

[DiverInAk]

??? You stated that after the shore tender played out approx. 100ft. of line and then signeled and got know reply...the tender hauled the divers in.....how then did they descend to a reading of 200ft.?

Sorry, I said at OVER 100ft of line they got concerned, I didn't make the point specific. This isn't really the point either. The gauges read 200'.

 

[texdiveguy]

Sorry, I said at OVER 100ft of line they got concerned, I didn't make the point specific. This isn't really the point either. The gauges read 200'.

So what is the point of your post....if you are aware of the incident then have you not followed up to find out any ME results on the cause of death of these 2 divers? Is this a hypothetical situation or a real incident?

 

[DiverInAk]

..... So what was seen at the site may have been a similar natural process,,,only the ME can determine the divers cause of death.

I don't know what's natural about foaming blood, but OK. My understanding is that the ME found air in several places where it didn't belong. I don't know the 'official' cause of death yet. Foaming blood sounds like gas bubbles in blood which spells embolism to me.

 

[DiverInAk]

So what is the point of your post....if you are aware of the incident then have you not followed up to find out any ME results on the cause of death of these 2 divers? Is this a hypothetical situation or a real incident?

The incident is real. The ME has not released cause of death. Nor does cause of death necessarily spell out what happened.

The point of my post is for general discussion regarding thoughts of what might have caused two trained healthy divers on tethers to be found well off their dive plan, decended to a depth of 200' or more feet and be pulled back up dead with a total time u/w of roughly 18 minutes?

If the ME says that they died of gas embolism caused by a rapid ascent, that doesn't necessarily explain why they were both at those depths and non-responsive or unable to arrest a rapid ascent. That would indicate that one or both were already incapacitated wouldn't it? If so, then why? What would do that? My only thought is that it had to have been in their tanks.