Question CO2 to induce panic attacks for treatments?

[Akimbo]

Akimbo, I am a retired industrial hygienist, and the 2014 ACGIH* TLV Booklet* states that the "STEL" level (Short Term Exposure Limit) for carbon dioxide is 30,000 parts per million. That is 3/100, or 3%. The NIOSH Pocket Guide states that the IDLH level for CO2 (Immediately Dangerous to Life and Health) is 40,000 parts per million, or 4/100 which is 4% CO2.

Those values are understandably very conservative when compared to pre-nuclear submarines. I have read many accounts of CO2 levels in the boat well above 6%. Headaches, rapid breathing, lethargy, for sure but not death or lasting effects. The comparative accuracy is likely the same since they used Dräger tubes on U-boats and functionally the same tubes on US boats.

 

[Akimbo]

Thinking more about this, I understand that competitive apnea divers also experience very high CO2 levels. Freediving classes teach conditioning exercises to increase tolerance to high CO2 and low Oxygen levels. I can't find my references but I believe that CO2 well above 8% is common. Does it apply? I can't say but it is an interesting data point.

 

[Kimela]

That sounds absolutely terrifying. Why would you do that to someone? No one is triggering a brain seizure to check it out clinically. Each one of these incidents, much like a bipolar episode, physiologically changes the human brain.

Sorry, this hits a little close to home for me. As someone who has watched his wife suffer debilitating anxiety attacks and be hospitalized more than a handful of times for manic and psychotic episodes, this just breaks my heart.

I'm with you on this one. However, the abstract indicates they were working with people who experience panic attacks as a result of lack of oxygen, to see if medication, exercise, or CBT will help (if I'm understanding the abstract correctly). My first thought was "why in the HELL would someone submit themselves to an intentional panic attack?" - but this made sense. If there's a greater purpose - and I'm getting paid for my suffering - and I might get free treatment that will reduce the number and severity of my panic attacks in the future, I might consider doing this. But I might also just see a therapist and skip this experiment. Shudder.

 

[Kimela]

I am curious how this much CO2 could ethically be used on patients?

There's much that has been done in the name of scientific research that was later deemed to be unethical and/or inhumane. In this case, I truly wonder if a patient could be competent to sign an informed consent - could they fully understand what the level of panic in a 'controlled environment', triggered by CO2 might feel like? I'm glad we have research, and the products of research, but this isn't one I'd volunteer for, and I don't get panic attacks.

 

[John C. Ratliff]

Speaking as both a diver/instructor and a trained industrial hygienist, I have a few more observations.

Concerning freedivers and CO2 buildup within the lungs, this is very short-lived. The exposure time is less than 5 minutes. Then, there is significant ventilation to get ride of the CO2 buildup. This would explain how extremely high levels could be encountered without long-term effects.

Concerning this therapy, again, this is a short-term exposure. While the amounts breathed are very high, the exposure time is also very limited. This should be taken into consideration when thinking about the ethics of this potential treatment.

Now, about longer-term exposures, the STEL I defined above is a limited exposure to 15 minutes. That’s why it’s called a STEL, or Short-Termed Exposure Limit.

The ACGIH (American Conference of Governmental Industrial Hygienists) publishes their TLV (Threshold Limit Values) and STELs as scientific standards, but they are not consensus standards that are used by OSHA for penalties. They are the recommended best practices. With this in mind, the tests that were done for scientific research need to be understood as experimental, but also very short-term.

Concerning the submarine exposures in older subs, Akimbo, those were under battle conditions or emergency conditions, and not recommended. Also, these standards don’t apply directly to our military, especially under battle conditions. Concerning taking measurements using Drager tubes, or other detector tubes, there is a + or - of 25% in reading detector tubes, if my memory is correct. They will get you into the ball park, but a calibrated instrument is really necessary to get an accurate reading of any chemical under question.

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There is, in toxicology, what is called the “dose-response” relationship. The response of the body is dependent upon the dose. And the dose depends upon the route of exposure, the type of toxic agent, the duration of the exposure, and the frequency of exposure (for those toxins which accumulate). CO2 is not usually related as a toxic agent, as it is a body metabolite. Yes, CO2 can be toxic, but so to can oxygen, which divers know can cause convulsions while breathing it at 100% breathing under pressure of greater than 2 atmospheres absolute. But, saying all this, I would not want to be a subject to this therapy.

SeaRat