Is it worth the trouble and expense to carry emergency oxygen?

[tbone1004]

I wonder how the safety benefit of carrying an AED compares to the safety benefit of carrying O2.

risk:reward. AED's are expensive. If you are diving with people that are overweight, are suspected or known high cardiac risk, etc. then I think you need an AED. We carry them when teaching, but I don't normally take them when I dive.
O2 is something that I think is mandatory regardless

AED is the only thing that has a chance to save your life if you get into a very specific situation and can't get to paddles in time which is why they are in airports, federal buildings etc. If you go into cardiac arrest, you need an AED. The question you have to answer is what is the risk of having someone need it. My dive buddies and I are largely all in our late 20's/early 30's, and in good health which puts us at near 0 risk of needing an AED. If I'm diving with someone who is obese and out of shape *possible to be obese and in-shape*, and in their 60's, that's a different discussion. Now I have a person who's high risk of a heart issue anyway, and now I'm putting them into a physical activity, not good.

O2 can make a lot of symptoms go away and not require any medical treatment. The risk of needing O2 for something is quite high with the type of diving we do. Being young and healthy has no bearing on the risk of taking a hit. The odds of you dying from not having O2 when you need it are a lot smaller than those of not having an AED. The odds of you needing O2 though, are a lot higher than you needing an AED.

A full O2 kit is $500 from DAN, $750 if you get the MTV-100 *recommended*. That's in a nice fancy Pelican case, has all of the fancy good lucking stuff etc etc. For $550 you can get a new AL40 *$200*, with a new O2 reg *$200*, with a RescuEAN with BVM etc *150*, and get essentially the same thing, but also something you can do IWR with if you need to, or just normal decompression.
An AED is $1500.

You are going to need the O2 more often than you need an AED, and it's a third of the price. No brainer for me to keep the O2 around all the time.

 

[Wookie]

I think as a profession dive operator carrying both is the correct choice. For the individual the benefit-cost ratio may not be worth the diminishing returns for the AED.

Yup, no longer a pro, but I'm still a commercial diver.

I kept them both when I sold the boat....

 

[2airishuman]

Hmmm. Interesting question and I want to make sure I approach the answer correctly. Are you asking which would likely provide a greater benefit to carry on a dive trip?

I would be interested in the answer, whatever approach you take to the question.

The broader question, for me, is the appropriate level of preparedness (in terms of equipment and training) while on a boat in a remote coastal (or inshore) area, on a trip that includes diving among other activities.

It is possible to be overprepared, that is, to place too much focus on a relatively minor risk.

 

[Wookie]

sure it keeps - but the tank still needs a hydro every 5 years

Not if you don't transport it in commerce or refill it. I don't even know when my last O2 cylinder hydro was. If I used it, I'd have to hydro it before I filled it again.

 

[uncfnp]

I would be interested in the answer, whatever approach you take to the question.

The broader question, for me, is the appropriate level of preparedness (in terms of equipment and training) while on a boat in a remote coastal (or inshore) area, on a trip that includes diving among other activities.

It is possible to be overprepared, that is, to place too much focus on a relatively minor risk.

Looking at it as which has the most dramatic effect on outcome in the event it is needed? The answer would be AED. It can quite literally bring back the dead.

But for the individual diver? I honestly think paying for and lugging an AED to remote locations is not worth the very low probability of use. I think others have touched on this. If you can manage it, O2 and a method to deliver it is certainly worth the effort. AED for the individual? No. Unless you are diving with an individual that chooses to dive despite a known risk for sudden cardiac arrest.

 

[rjack321]

sure it keeps - but the tank still needs a hydro every 5 years

No it does not.
If its hasn't been used, you aren't obligated to use or empty it just because the hydro has expired. Just keep it in the box indefinitely

 

[rjack321]

Unless you are diving with an individual that chooses to dive despite a known risk for sudden cardiac arrest.

There are a lot of divers in their ~50s who have no "known" risk and there is no reason symptomatic reason to conduct a stress test - but have sudden LAD occlusion. We see one or more of these widowmaker MIs here in A&I every year. Not having any collateral flow, these are the divers who are going to live or die based on whether there is an AED around. The people with gradually accumulated symptoms, who get flagged as "known risks" are the ones who tend to have had time to develop collateral flow. Thery're far more likely to survive a semi-remote out of hospital MI with no AED.

 

[uncfnp]

There are a lot of divers in their ~50s who have no "known" risk and there is no reason symptomatic reason to conduct a stress test - but have sudden LAD occlusion. We see one or more of these widowmaker MIs here in A&I every year. Not having any collateral flow, these are the divers who are going to live or die based on whether there is an AED around. The people with gradually accumulated symptoms, who get flagged as "known risks" are the ones who tend to have had time to develop collateral flow. Thery're far more likely to survive a semi-remote out of hospital MI with no AED.

Yes, it seems that we hear of those 50 something male divers in the A&I forum all too often. But the question I think is not what population benefits from AED use but the benefit-cost ratio as it applies to nonprofessional dive trips. The greatest chance of benefit would be seen in the highest risk groups, hence those with known risk of sudden cardiac death. And honestly, for those true “widow maker” events, I am not sure even an AED in a remote location would be enough.

 

[johndiver999]

I always try to have oxygen in a scuba tank every time I am diving where there is a chance of decompression sickness. If it is a 20 ft dive, I'm not bringing it, but for anything else it gets brought on board.

The cost to fill an old (clean) out of hydro tank with 2200 psi of oxygen and a cheap (clean) first stage and a cheap second stage and a button pressure gauge and a $6.00 can of green pain from Home Depot is pretty low. And if you have a good valve on the tank and some luck, you should not have to fill the tank for years. There has to be somebody who will do you a favor and fill a tank with a little oxygen. If you keep the regulator sealed up in a $20 dedicated dry bag - maintenance (and purchase) costs are very low.

 

[2airishuman]

No it does not.
If its hasn't been used, you aren't obligated to use or empty it just because the hydro has expired. Just keep it in the box indefinitely

From a regulatory standpoint this is correct. As long as the cylinder was in hydro when filled it is legal, at least under USA rules, for transportation.

At some point the question becomes whether you still trust the valve and the contents. I would not trust a 50 year old cylinder of O2. I don't think I would trust a 25 year old cylinder. I would like to be able to exchange cylinders (or drain inspect and refill) every few years because, at market rates, this is really just a matter of a few dollars and well worth it.