Narcosis Effects or... ?

[Topdown134]

TSandM, DDM,

Thanks for your replies. That's the way I understood narcosis to work as well. There were no toxicity symptoms, everybody was diving off the same compressor, and we used the same tanks for the rest of the trip with no recurrence, so I don't think that was an issue. She does not have a remarkable medical history -- in fact, it's pretty benign. She has not seen her primary care practitioner, but I will suggest it. I'm worried about the unpredictability of the possible psychiatric/psychological condition combined with an unwillingness on her part to really probe what happened. We've been dive buddies for all of her nearly 200 dives now, with the exception of her OW and AOW training, so maybe making the next trip contingent of getting her checked out might be an angle.

 

[boulderjohn]

I will start off by saying that I am not a physician, so I may be off base here. I wonder if it might not be something that is entirely unrelated to diving, something that just happened to occur during a dive.

A couple of years ago my wife was doing some yard work at a cabin we owned with her sisters. She started acting strangely, as if she had no understanding of where she was or what she was doing. They immediately took her to the hospital, where everyone was mystified except a nurse who correctly identified it as transient global amnesia (TGA). When she was supposedly cured, they called me (I was not in that state). The doctor explained it all to me and put her on the phone with me, where she very lucidly explained what had happened and that she was perfectly fine. The next day she had no memory of talking to me.

Soon after that occurred, someone started a thread on ScubaBoard about an incident in which his dive buddy got TGA during a dive. He arrived at the surface with no memory of having done the dive or even beginning it, and he was wondering how they got to where they were. It sounded very much like your case, except for the sleeping part.

Maybe it was something along those lines.

 

[Mr. Black]

I would also say not narcosis- sounds almost like hypoxia.

Right!!!

n00b question: Could this be a carbon monoxide issue ? And the rest of the group just weren't as sensitive ?

 

[AfterDark]

I would also say not narcosis- sounds almost like hypoxia.

OP did you check her air consumption for that dive? A buildup of C02 from overbreathing her reg could produce those symptoms. Hypoxemic hypoxia: One possible cause hypoventilation inadequatepulmonary minute ventilation.

 

[mala]

well done topdown for getting her home.

could have been nasty.

 

[Duke Dive Medicine]

Right!!!

n00b question: Could this be a carbon monoxide issue ? And the rest of the group just weren't as sensitive ?

Not a noob question, a good one. Highly unlikely considering the symptom progression; unconsciousness from CO poisoning does not spontaneously resolve on surfacing like this did, and she'd have been much sicker and would have required medical intervention.

@Topdown: did she by chance take any medications prior to this dive?

 

[Topdown134]

To the above questions, I am not sure about the meds, but I am almost postive she had no prescription drugs. At most, it was an herbal supplement and maybe 400 mg Advil.

Her air consumption was extremely low. Usually, she's within about 100 psi of me on an 80 cu. ft. tank. This time, she came up with nearly 1800 psi (starting pressure about 2900-3000 psi) while I surfaced with 900 psi. Admittedly, I was doing a lot more work, but if she overbreathed her reg, it wasn't for very long.

 

[fred3798]

How did she dive again that week without going to the hospital to figure out if she had something else really wrong?

 

[Duke Dive Medicine]

To the above questions, I am not sure about the meds, but I am almost postive she had no prescription drugs. At most, it was an herbal supplement and maybe 400 mg Advil.

Her air consumption was extremely low. Usually, she's within about 100 psi of me on an 80 cu. ft. tank. This time, she came up with nearly 1800 psi (starting pressure about 2900-3000 psi) while I surfaced with 900 psi. Admittedly, I was doing a lot more work, but if she overbreathed her reg, it wasn't for very long.

May I ask what the herbal supplement was? Also, was she diving compressed air or nitrox? If nitrox, what was the O2 percentage, and was it checked before the dive? Is your friend a smoker? If so, how much and for how long?

Best,
DDM

 

[Topdown134]

To Fred3798:

She basically refused to talk about the incident, and acknowledged that she was aware that she was asleep at least early in the dive. That's why I'm leaning to an emotional/psychological influence. She would not have gone willingly to a hospital, and since we were on a liveaboard, it would not have been a simple trip. In retrospect, however, that's not much of an excuse if she couldn't take care of herself.

To DDM,

I don't know the exact supplement, or even if she had it with her on this trip, but she had been using something to moderate the effects of menopause. I know she also takes a GNC branded multi-vitamin package. We were diving air, and she is not a smoker. I'd say her respiratory capacity is above average based on the fact that we are dedicated fitness enthusiasts and have a pretty intense work out regimen.