O2 for everyone?

[ronski101]

At the risk of rattling a few cages as I have been known to do, why is O2 not part of our every day scuba diving experience? I remember when safety stops were unheard of and the same with computers. So as diving has matured as a sport, it seems strange that since people who are suspect to have a DCS hit on a boat are immediately given O2, why not as a preventitive measure when you are done with a dive and say your computer shows that you are in the yellow nitrogen wise that you would not automatically breath O2 for say 5 min. during your interval as a safety measure? Hasn't DAN done any studies on this yet? Remember, computers only approximate what nitrogen you really absorb and if I recall, some people have got hit and were still within normal diving limits. Drag racers and football players use O2 to sharpen their game why don't us divers do it for additional safety? Remember the oxygen bars? I am looking forward to the edges of both sides of the bell curve of responses to this one.......

 

[vladimir]

If only we could get the football players to donate the O2 that they are wasting in the mistaken belief that it can sharpen their game. As rare as DCS is, I doubt the small benefit of wholesale administration of oxygen would outweigh the cost of the gas, the cost of devoting boat space to it, and the risks of transport and storage.

 

[TSandM]

It comes down to risk assessment. DCS in recreational divers is quite rare, and usually very treatable. Oxygen toxicity underwater, however, is all but reliably lethal. (There have been two recorded cases that I know of where an extremely skilled buddy (instructor) responding instantly, has saved the life of someone seizing on O2.) Recreational divers are generally not trained to a level to maintain buoyancy control with pinpoint accuracy in the face of significant task loading, and buoyancy control is harder in the shallows (and O2 can't be used below 20 feet). It all adds up to someone taking a major risk of death to avert an extremely tiny risk of treatable injury.

 

[vladimir]

Oxygen toxicity underwater, however, is all but reliably lethal. (There have been two recorded cases that I know of where an extremely skilled buddy (instructor) responding instantly, has saved the life of someone seizing on O2.) Recreational divers are generally not trained to a level to maintain buoyancy control with pinpoint accuracy in the face of significant task loading, and buoyancy control is harder in the shallows (and O2 can't be used below 20 feet). It all adds up to someone taking a major risk of death to avert an extremely tiny risk of treatable injury.

I believe Ronski was proposing O2 administration post-dive, on the boat, rather than in the water:

why not as a preventitive measure when you are done with a dive and say your computer shows that you are in the yellow nitrogen wise that you would not automatically breath O2 for say 5 min. during your interval as a safety measure?

 

[popje]

Because it's pretty much useless on the surface with a healthy diver. Might help a little with off gassing but really it'd be a whole lot more effective at a higher partial pressure and that's not permitted for recreational divers. In the case of an injured diver, you're talking about more than just eliminating the excess nitrogen.

 

[Dr Deco]

Hello ronski101:

Oxygen ?

1. You are in the deco safe zone virtually always because of the safety factors in the tables. They are designed to protect the most susceptible of divers. Everyone else has even more protection.

2. A few minutes of oxygen would not really do anything physiologically if you truly had a problem.

3. Oxygen is primarily of value in reducing the bubble load in the veins when bubbles are actually present. It is metabolized by the tissues and does not reach the venous blood. This is of value if a diver has copious bubble loads and is in danger of arterialization. This, fortunately, does not occur in practice. Avoid this by eliminating Valsalva-like maneuvers such as straining when board the boat [climbing the ladder]

4. If a diver has expended considerable energy when on the bottom, e.g., fighting an underwater current, increased nitrogen washout would be advised on assent. This would be better performed at an extended safety stop.

5. Bottles and bottles of stored oxygen onboard are not without risk in the event of a small fire. It turns small fires into big fires.

6. Oxygen bars at one atmosphere do not really oxygenate the arterial blood. Psychologically, it makes a difference but not physiologically. [It does make a difference to the purse of the bar owner.] In sports, perception is important. If you believe it helps, it probably will. The precapillary sphincters of your tissues, however, do not experience “perception.”

Dr Deco :doctor:

 

[Bubble_Boy]

Just use nitrox...

 

[ronski101]

So if O2 does not do you any good when you are back on the boat why is it standard procedure to give it to you if you have decompression sickness symptoms? I thought it's use was to attempt to provide oxygen to the cells because bubbles in the veins and arteries were preventing blood from doing that job. It would take one hell of a fire to cause an O2 tank to get hot enough to explode and by then the boat would be toast anyway. I am suprised that dive boats don't use it as a way to scare a few more $'s out of the customers.

 

[Tortuga68]

So if O2 does not do you any good when you are back on the boat why is it standard procedure to give it to you if you have decompression sickness symptoms?

3. Oxygen is primarily of value in reducing the bubble load in the veins when bubbles are actually present

.....

 

[Dr Deco]

ronski101:

1. Oxygen is value of when there is something to treat.
It is possible to decrease the surface interval by accelerating nitrogen washout, but this requires calculations - and a tight fitting mask [or other delivery system].

2. The oxygen tanks will not explode. They have a relief valve that will vent excessive oxygen pressure. It will vent this oxygen into or around the boat however. A bad situation, indeed.