How does oxygen treat DCS/AGE?

[Henryville]

The difference between DCS and AGE is where the bubble forms. For DCS, the bubble forms in the a tissue (muscle, organ). For AGE, the bubble forms in your blood stream. The reason AGE is more serious is bubble in your blood stream can stop the blood flow to a specific area of the body causing other issues. Over expansion of the lungs is a different issue. Some of the aviolii have ruptured, causing bleeding or rupturing/collapsing the lung. How do stay off your lungs until they heal? Although the body many have had high nitrogen levels when the lung was over expanded, the high nitrogen level did not cause the over expansion, it was trauma from not allowing the gas to leave the lungs.

Hope this helps - Tom

More specifically, the AGE is a bubble in the arterial side of your circulatory system. As it travels toward the capillaries, it eventually comes to a point where it (the bubble) is too big to pass further, and thus cuts off blood flow from that point on, just like a clot. If, as will often happen, the bubble travels into the arteries supplying the brain, you basically get a stroke.

Overexpansion injury comes into the picture here because it is one way to get an AGE. Alveoli burst, gas enters the arterial side, AGE. Another way to get an AGE is through a right to left shunt, one type of which is called a PFO. There are lots of posts on this on the board. It sounds like the OP is intending to find out what caused the AGE in this case. Someone more qualified than I should weigh in, but I believe the advice on what to do next and whether to dive again will depend on what the source of the AGE was.

There are commonly bubbles in the venous side when ascending from a dive, as long as their size and growth are controlled with an appropriate ascent/decompression profile, they are not a big deal as they are trapped and eliminated in the lungs.

 

[logos]

I'd think of two mechanisms:

1. Increased nitrogen gradient helps you breathe off nitrogen faster. In theory that should result in faster bubble shrinkage, barring some sort of bubble surface gas-liquid interface strangeness.

2. Oxygen is given to stroke victims with the rationale that the blockage may be partial. In particular, it may block the passage of blood cells but allow the passage of plasma (the fluid part of blood). By giving 100% oxygen you increase the partial pressure of oxygen in plasma. Unfortunately, this is still a small percentage of the total oxygen carrying capacity and no substitute for reperfusion. This is also the mechanism by which blood substitutes like Polyheme theoretically may be usefull in stroke/MI prior to reperfusion.

 

[wetvet]

Thanks for the replies. If you are interested, I posted the incident in this forum under "heres one for you" (Im not sure how to link these threads). Tentative diagnosis is that I had a stroke. Nobody knows if the blockage was caused by clot or bubble, but resolution was 100% without treatment. Neurologist is calling this an AGE, and other hyperbaric docs on the board claim to have seen AGE's resolve without treatment. This is more of a theoretical question on what the diagnosis would have been had I been treated immediately with O2 on the boat. Again, my assumption is that by taking N2 out of the system, you accelerate bubble reduction, but have had comments from others (experienced instructor whose opinion I respect) who claim that bubbles cannot be eliminated except by compression. Maybe the mechanism of 1ata O2 isn't well known, and it's an automatic treatment because it "might" do a whole bunch of things, and all of them are beneficial.

To the medical types.....If I presented the exact same way as described in "heres one for you", only had been given O2 first aid, would it have changed your presumptive diagnosis?

Again....thanks to everyone for giving me input on this.....I really want to understand how it all works, so I can decide if I can get back in the water again.

Wetvet

 

[T-Dog]

Again....thanks to everyone for giving me input on this.....I really want to understand how it all works, so I can decide if I can get back in the water again.

Wetvet

If you haven't already, you should contact DAN with that question.
Also here are two articles you maybe interested in reading.
DAN Divers Alert Network : Decompression Illness: What Is It and What Is The Treatment?
DAN Divers Alert Network : Decompression Illness: What Is It and What Is The Treatment?

Safe Diving!

 

[Wayan]

Thanks for the replies. If you are interested, I posted the incident in this forum under "heres one for you" (Im not sure how to link these threads). Tentative diagnosis is that I had a stroke. Nobody knows if the blockage was caused by clot or bubble, but resolution was 100% without treatment. Neurologist is calling this an AGE, and other hyperbaric docs on the board claim to have seen AGE's resolve without treatment. This is more of a theoretical question on what the diagnosis would have been had I been treated immediately with O2 on the boat. Again, my assumption is that by taking N2 out of the system, you accelerate bubble reduction, but have had comments from others (experienced instructor whose opinion I respect) who claim that bubbles cannot be eliminated except by compression. Maybe the mechanism of 1ata O2 isn't well known, and it's an automatic treatment because it "might" do a whole bunch of things, and all of them are beneficial.

To the medical types.....If I presented the exact same way as described in "heres one for you", only had been given O2 first aid, would it have changed your presumptive diagnosis?

Again....thanks to everyone for giving me input on this.....I really want to understand how it all works, so I can decide if I can get back in the water again.

Wetvet

In almost all cases diagnosis of illness are differential ie it because of the S&S it can be one of this bit can be one of these.

If the S&S lead me to believe that there was a possibility of a DCI/DCS then yes O2 would be given no questions asked.

O2 depending on how it is given will significantly reduce the uptake of N2 and assist if the elimination of N2 as well - it assists in getting the person stable.

Of course DAN needs to be consulted and see the post below for treatment protocols etc. In any case a Hyperbaric Medicine Doctor should be consulted so as you can make an informed decision as to whether to dive again or not.

IN some cases now in stroke cases hyperbaric treeatment is used to assist in the healing process, I believe that the figure is treatment sometime with in the first 3 hours of onset of the stroke.(different tables to divers but same mechanism)

 

[rawls]

Thing that I question is the tendency for AGE symptoms to happen rapidly as opposed to DCS. But again, DCS could cause AGE. In either event it seems the symptoms were delayed making me wonder if it was actually an AGE or a case of the bends. Then there is the fact you have a septal defect. I'm not sure but wonder if pressure could increase the risk of bubbles shunting across the defect? All in all it sounds like the bends to me since the symptoms were delayed as they were.

 

[wetvet]

Rawls....that is the 17 million dollar question. The hyperbaric doc DIDN'T think it was DCS (didn't even put me in the chamber), since it resolved spontaneously. He didnt really think it was AGE either.....he felt it was a stroke caused by a clot, and just happened to be timed right after a dive. The neurologist (couple days later) said I have no reason to have any clots.....it must be dive related. I don't expect to ever get a definitive answer (I'm getting a cardiac workup soon, but I expect that to be normal....if there was a worsening of my shunt, I'd have noticed it in the gym). I would really like to know what happened, though. Scary to think that a completely unremarkable dive can result in deficeits that severe.

Thanks for all the inputs.

Wetvet

 

[rawls]

Wetvet...Have you been diving since this occurrence or have the docs said anything about being able to go diving again. I truly hope you will be able to get back into the water....

 

[wetvet]

No, haven't been in the water since...still in the "investigation" phase of things. Until I find out a bit more, I'm not getting in....hopefully in the spring.