Death of a recreational diver after a fall on board MV Elaine

[Duke Dive Medicine]

I almost never disagree with you, but I'm going to here...

The liver and spleen (and other abdominal organs) have very rich blood supplies, but are rarely visualized after minor blunt trauma, unless the patient has an emergency abdominal exploration or dies of something else and has an autopsy. So just like the subcutaneous soft tissue of the body easily bruises with trauma that is not enough to cause a medical emergency (e.g. a black eye), the internal organs and soft tissues probably also bleed a bit with trauma that is not enough to be life threatening or even to cause a significant hemodynamic problem.

If this diver fell (or got punched in the gut because he took someone's regular bunk or bench space), he might well have had "minimal abdominal bleeding" that would have never been of any consequence. The only reason that we know about it is that he happened to die from something else and underwent an autopsy.

Regarding the point about the gas embolism, I agree. However it's important to realize that a systemic gas embolism could have formed from the rapid emergency ascent even if he had died of something else at depth and then was just shot to the surface (especially if he had a PFO, like 25% of the population), so the presence of a gas embolism doesn't necessarily mean that the embolism was the cause of death... but the pathologist might have been taking other things into account in drawing that conclusion.


M

Good points all, Mike, and I should have qualified my statement. There's no definition of "minimal" given in the accident report, but it does say that the bleeding wasn't enough to cause immediate shock, which lowers the acuity but still leaves things a bit nebulous. Yes, it's theoretically possible that the gas embolism was incidental while he was being brought to the surface, but the post-mortem specifically lists gas embolism as the cause of death so I'd tend to go with the opinion of the consultant.

Beyond that we're speculating, which neither of us likes to engage in ;-)

Best,
DDM

 

[doctormike]

Good points all, Mike, and I should have qualified my statement. There's no definition of "minimal" given in the accident report, but it does say that the bleeding wasn't enough to cause immediate shock, which lowers the acuity but still leaves things a bit nebulous. Yes, it's theoretically possible that the gas embolism was incidental while he was being brought to the surface, but the post-mortem specifically lists gas embolism as the cause of death so I'd tend to go with the opinion of the consultant.

Beyond that we're speculating, which neither of us likes to engage in ;-)

Best,
DDM

Exactly, and of course I always defer to you for the hyperbaric medicine stuff, so I assume that you are right, if they identified a gas embolism as the cause of death, it probably was.

 

[mmadiver]

Report stated the loop was out of his mouth. If the rebreather was totally flooded he would have been very negative.
Sending him up with a bag was probably the only thing they could do from that depth. Having an unconscious diver and a huge deco obligation is a lose/lose situation I hope to never encounter.

Great points. Any comments/best practices in handling an unconscious diver and a deco obligation?

 

[MalibuJerry]

Just read the full report, so, my earlier comment was wrong, he did have internal injuries which if not the cause, were the proximate event. Still, it would be unusual baring any indication otherwise to call the dive after the fall. The question remains, would he have died regardless of doing the dive? If, for example, he had bailed on the dive and went below decks for a nap would the outcome have been different? I imagine his probabilities would have improved, but I am not clear if his outcome would have changed.

The best practices for bringing an unconscious, non breathing diver to the surface, particularly with a flooded rebreather, are not well worked out. A lot depends on the other divers' deco obligations. If they are not much, they can move to the surface pass the diver off to the boat and return to do their now modified decompression. On a deep dive like this they have very few options. If there is a safety diver, even if on board, one can shoot a bag asking for assistance and a diver might be able to come down to retrieve the unconscious diver. This all takes time of course. Moreover, if the airway of the unconscious diver is closed it is going to be difficult to bring him to the surface under any circumstances without an embolism. If he is breathing, one can hold the regulator in his mouth and do deco stops to get him to the surface without an embolism.

 

[Tigerman]

Given that the injury was not immediately life threatening, I think its safe to asume that his odds of surviving would have been much better above water and quite possibly the injuries might have been neglible.
A medical issue above water is a bit more manageable than it is below, especially if feeling bad make you act irrational..

 

[Ken Kurtis]

In the US, OSHA considers them to be commercial divers if they are on any gas but air.

Don't forget about the Dixie Divers (Florida dive operation) exemption.

In short, Dixie Divers wanted their instructors to be able to dive on nitrox without having to comply with commercial diving requirements (chambr on site, stand-by diver, stuff like that). They applied to OSHA for a waiver that would allow their paid staff to dive nitrox and not be considered commercial divers. OSHA eventually granted the waiver and also stated either (I can't recall which) that the waiver would be considered to be applied to any other outfit that wanted it or they would grant an identical waiver to anyone else who asked. But essentially, the Dixie waiver effectively applied to the entire professional diving community in terms of OSHA employer/employee relationship.

Point is, instructors can dive air or nitrox (I think there was a 40% limit as well) and not be considered commerical. I know it has nothing to do specifically with the fatality but since Frank mentioned it, thought I'd point it out.

And to anticipate the follow-up question: I have no idea how OSHA charactarizes an instructor teaching mixed gas or above 40% O2 mix but my guess is commercial and those standards (commercial) would apply. It may simply be that no OSHA complaint has been filed for any accident that's happened under these teaching conditions.

- Ken

 

[MalibuJerry]

Given that the injury was not immediately life threatening, I think its safe to asume that his odds of surviving would have been much better above water and quite possibly the injuries might have been neglible.
A medical issue above water is a bit more manageable than it is below, especially if feeling bad make you act irrational..

All other things equal, I agree. The probability of a fatality is higher if you are underwater and have a medical event. But the probability of a fatality above water with the same medical event is not zero. Given that he did not sense any problem for a while, it might have been the case that if he had kitted down and gone into the bunk for a nap while his friends did a 3 hour dive, he might not have survived as well.

The analysis of this accident is quite difficult because it is compounded by the fact that his buddies blew a bag and sent him to the surface with an apparently closed airway, and because we don't have the counter factual…what if he did not dive? The other factor not considered is that he might not have felt fine and just said so. That then would be another story.

I don't think the conclusion is if you fall on the deck and you feel just fine don't dive. Having said that, I'm not sure I know what the conclusion is.

 

[Ken Kurtis]

I don't think the conclusion is if you fall on the deck and you feel just fine don't dive. Having said that, I'm not sure I know what the conclusion is.

I think the conclusion is that if you fall, don't immediately get up and say you're fine and proceed.

I think you acknowledge that something that shouldn't have happened just did, check out your gear thoroughly to make sure nothing got damaged, check out yourself as throughly as you can to make sure there's nothing else going on, maybe try to figure out why you fell and does that indicate anything else, and THEN decide to go ahead with the dive. It's not a 10-second I'll-be-fine-get-out-of-my-way scenario. What's the harm in waiting a bit? Although Jerry rightly points out that we don't have a counter factual, what we do know is that he fell, he got up, he dove, he died. There may or may not be a direct connection but we know this outcome.

The other thing we see in accident analysis is that it's rarely one thing, let alone the first thing, that gets you. It's the second, third, fourth or whatever number of things going wrong in a sequence that ends up causing overload and doing you in. So the counsel is that when the first thing goes wrong, stop and fix it, or abort until it can be rectified. For all we know, the fall on the deck was #1 of a sequence and while the fall itself may not be the fatal culprit, it may have limited his ability tro deal with whatever other things happened to him during the dive that resulted in his demise.

- Ken

 

[MalibuJerry]

I agree with Ken on this with one exception. This may have been #2 or #3. Perhaps he fell because he was rushing to meet up with his buddies in the water? we will never know. But separate from this, and applicable to all diving, is Ken's recommendation. If something goes wrong, fix it before it cascades out of control.

---------- Post added December 16th, 2013 at 01:16 AM ----------

Oh, and Ken, what are you doing up at this hour? Go to bed…I have an excuse I'm in Malaysia.

 

[Hickdive]

I'm not trying to be obtuse here. How does the MAIB consider dive instructors (BSAC, PADI, the like) who are being paid to teach a recreational class? In the US, OSHA considers them to be commercial divers if they are on any gas but air.

Edward explains it in a nutshell.

In the UK if you're teaching for hire or reward you fall under the heading "commercial" diving with the HSE (Health and Safety Executive) who have a published code of practice for diving instructors who are being paid.

If you're an instructor that is not being paid or rewarded (e.g. A BSAC Instructor teaching within a BSAC club) then you are not subject to HSE regulations. However, you are expected to follow BSAC's "Safe Diving Practices" and you would be foolhardy not to and something went wrong.

Other non-commercial training Agencies such as SSAC and SAA have similar requirements of their volunteer instructors.