When High Does Mean Low: Autism, mHBOT, and Dan Rossignol

7 Oct

A while back on Autism Street, I questioned the claim by DAN! doctor, Dan Rossignol, that children he wrote about in an article that appeared in the pay-to-publish, not peer-reviewed journal Medical Hypotheses, were treated with “mild hyperbarics” at 1.3 ATA.

In hyperbaric medicine, the term “1.3 ATA” has the very specific scientific meaning of “1.3 Atmospheres Absolute”, and it is a likely overstatement (due to rounding) of the actual treatment pressure in that particular study. Put simply, “atmospheres absolute” refers to the total pressure, and includes that actual pressure of the atmosphere. It’s also an absolute pressure that is apparently beyond the physical capabilities of the equipment that was used (a Vitaeris 320), unless the chamber were located well below sea-level, or housed inside another, larger, and pressurized hyperbaric chamber. I suggested that he publish an erratum. He was kind enough to reply to my e-mail, in which he responded, in part with:

HBOT measurements are typically reported to 2 significant figures, i.e. 1.3, 1.5, 2.0, 2.4, 3.0 ATA, etc… Therefore, this properly rounds to 1.3 ATA (we did not report the pressure to 3 significant figures as would be the case with 1.30 ATA).

As it turns out, this may not be entirely true. I responded with the following:

At least two of the papers cited in your references (Collet et al., and Montgomery et al.) show treatment pressures of 1.75 atmospheres. There might even be more. Would those have been acceptable to be published at 1.8? Do you think a real peer-reviewed journal would be requiring that you publish an erratum? I think so, but I could be wrong. In many of the “typical” numbers you list, reporting to 2 significant figures does not change the accuracy anyway (2.0 ATA is stated instead of 2.00 ATA, 3.0 ATA instead of 3.00 ATA, etc.).

Dr. Rossignol, to my knowledge, did not publish an erratum. He did not comment on the apparent overstatement of treatment pressure further. So it would appear that he intends to stick with his assertion that,

HBOT measurements are typically reported to 2 significant figures, i.e. 1.3, 1.5, 2.0, 2.4, 3.0 ATA, etc…

That’s fine, we can work with that, but remember it. It’s going to be very important in a minute.

I later wrote a little more about the physics of so-called “mild hyperbarics” again, and included a notation of a new study that Dr. Rossignol, appeared to be working on.

There’s another “hyperbaric therapy as a treatment for autism” study underway. It appears to be headed up by Dr. Rossignol, and has three clinical locations supervised by Doctors Liz Mumper (Virginia), Cindy Schneider (Arizona) and Jeff Bradstreet (Florida) – none of which appear (according to a search at ABMS) to have board certification in Developmental-Behavioral Pediatrics, Child Neurology, Neurodevelopmental Disabilities or Undersea & Hyperbaric Medicine.

Well, it looks as though that study has wrapped up. Is there a forthcoming publication that will claim that the children in the study were treated with “mild hyperbarics” at 1.3 ATA? Will it be published in a journal like Medical Hypotheses, JAPandS, or Medical Veritas? If it’s headed for a respectable peer-reviewed medical journal, and the treatment pressure is claimed to be 1.3 ATA, there might be a problem.

You see, in the real world, a Vitaeris 320, is probably not a hyperbaric chamber that can produce a full 1.3 Atmospheres Absolute – even at sea-level. Its non-rigid construction means that it’s directly influenced by the ambient atmospheric pressure. To calculate the absolute pressure inside the chamber at any given time doesn’t require anything more than knowing the current actual atmospheric pressure outside the chamber, and the slight pressure added by the compressor that inflates it. Although it does vary slightly, at sea-level the average atmospheric pressure is about 14.696 PSI. According to the manufacturer’s spec sheet, the chamber introduces an operating pressure of 4 PSI, which would yield a total pressure of about 18.696 PSI – 1.27 ATA. Don’t forget, that’s at sea-level!

The study mentioned above, lists the following clinical trial locations:
Phoenix, Arizona
Melbourne, Florida
Charlottesville, Virginia
Lynchburg, Virginia

Are all of those cities at sea-level? No.

Will this matter? Absolutely.

It’s a simple fact of physics that as elevation increases, atmospheric pressure decreases. Although there are several influencing variables involved, this is probably most easily understood in layman’s terms by knowing that weight of the column of air above you gets smaller as your altitude increases (as you ascend, the column above you is shorter and simply weighs less – exerting less pressure).

So what does this mean for this study? It means that if the study used Vitaeris 320 chambers, and reports that children were treated with 1.3 Atmospheres Absolute, it should raise more than a few eyebrows.

Firstly, if the study does not report actual atmospheric data for pressure at the study locations during treatment, it will be incomplete. Remember, for a non-rigid chamber, treatment pressure is measured by adding the actual ambient pressure to the pressure added by the compressor used to inflate the chamber. There is no way to measure the actual treatment pressure without knowing the actual ambient atmospheric pressure at the time of treatment.

Side note: It could be tempting for one to read a weather report from the National Weather Service in the U.S. and simply think that the pressure reported is the actual ambient atmospheric pressure at the study location (station pressure). Unfortunately, that’s not how it usually works. The National Weather Service typically reports “altimeter pressure” and “sea-level pressure”. See section 11.6, Table 11-2 from the Federal Meteorological Handbook No. 1. These adjusted pressures (corrected for elevation and temperature) are done to make pressure systems on weather maps more meaningful (and not simply reflective of the topography), and to allow aircraft pilots to adjust their instruments to the current conditions. With an altimeter calibrated to what the pressure “would be” at sea-level, instruments can accurately reflect the actual altitude of the plane. This is important if you intend to land on a runway that is always 1135 ft. above sea-level.

Secondly, if the study does not claim to have “measured” the treatment pressure, but instead asserts that it is 1.3 ATA, it will be difficult for any publication to substantiate the claim that the treatment pressure was uniformly (or even approximately) 1.3 Atmospheres Absolute at all study locations, due to the varying elevations of the study locations.

Let’s use Phoenix, Arizona (one of the study locations) as an example. The elevation of Phoenix, Arizona is approximately 1135 ft. above sea-level. This means that the ambient atmospheric pressure is about 14.10 PSI simply due to the elevation. 14.10 PSI plus an added 4 PSI gives us a total of 18.10 PSI – 1.232 ATA! Using Dr. Rossignol’s statement,

“HBOT measurements are typically reported to 2 significant figures, i.e. 1.3, 1.5, 2.0, 2.4, 3.0 ATA, etc…”

1.232 ATA in Dr. Rossignol’s words, “properly rounds to” 1.2 ATA!

Will the study report this? Or will it claim a very unlikely (if not impossible) treatment pressure of 1.3 Atmospheres Absolute? Following Dr. Rossignol’s apparent rounding preferences, we’re talking about a potential overstatement of the pressure added by the hyperbaric chamber of 50% for Phoenix alone. The Lynchburg, Virgina study location will quite likely present similar problems (elevation 938 ft. above sea-level) for Rossignol’s work. Is Dr. Rossignol, really concerned about the accuracy of the science in his work? We might just find out soon enough.

For anyone interested, here’s a table of estimated total pressure provided by a Vitaeris 320 at selected U.S. cities. Keep in mind that these estimates reflect the manufacturer’s specification of 4 PSI of operating pressure, and the expected atmospheric pressure due to elevation alone, and do not account for the slight variations in the weather. (Elevations retrieved from Airnav.com).

Estimated total pressure provided by a Vitaeris 320 at selected U.S. cities

It’s no surprise that parents of autistic children who “believe” that “mild hyperbarics” will somehow provide benefit for autism itself, would seek insurance reimbursement. In fact, some may interpret a statement by Dr. Rossignol to express such a view:

One of the reasons we wanted to study the 1.3 ATA chambers is because this is something that is available at home. We hope that if it does work and is proven, we can begin to have insurance reimburse for hyperbaric and this is one of our goals, as well.


Besides the obvious problem that scientifically “proving” that treatment with “1.3 ATA” will be difficult with chambers that likely don’t provide 1.3 Atmospheres Absolute, what are insurance companies supposed to think? Would insurance companies like the idea of reimbursing for HBOT treatment at a specific pressure that really isn’t?

14 Responses to “When High Does Mean Low: Autism, mHBOT, and Dan Rossignol”

  1. Brian Deer October 7, 2007 at 12:32 #

    I’ve never read anything in Medical Hypotheses, and I didn’t know till now that there were page charges.

    Do the items carry the word “advertisement”, as some journals have deemed appropriate?

  2. Club 166 October 7, 2007 at 12:44 #


    Thanks, Do’C for doing the math and catching Rossignol in his own web that he has spun.


  3. Matt October 7, 2007 at 13:53 #

    Another side of the “insurance” question.

    Are these devices UL listed when used in this manner?

    these bags (calling them chambers is marketing spin) are being pumped with enriched air (excess O2).

    Neubraner’s brother posted elsewhere about safety tests they have done on these bags with oxygen. When asked if that means that they are taking on the liability that testing implies, he remained silent.

  4. Joseph October 7, 2007 at 14:54 #

    So basically, for an autistic kid living in Albuquerque or Denver, an equivalent, or even better treatment, would be to take them a few days down to sea level. Did Dr. Rossignol ever think of that or recommend it?

  5. Do'C October 7, 2007 at 17:36 #

    “So basically, for an autistic kid living in Albuquerque or Denver, an equivalent, or even better treatment, would be to take them a few days down to sea level.”

    Interesting point Joseph.

    Let’s see. 40 hours of mHBOT with O2 enriched air, cooped up in a noisy nylon bag at about $4,000


    Ten full days in southern California (240 hours) with 02 enriched air, trips to Disneyland, Legoland, Sea World, The San Diego Zoo, and the beach at about $4,000 ($400/day).

    If I lived in Denver, and thought the tiny increase in blood oxygen would somehow be beneficial, it wouldn’t be a difficult decision in my book.

    Of course missed work can be a challenge. Making it a 7-day trip would still provide 168 Hours of fun in the oxygen-rich environment and leave, about $1200 to cover for the missed work.

  6. Rick Neubrander October 7, 2007 at 21:57 #

    Thanks Matt for misrepresenting what I said. I had to check my facts before posting a reply so as not to be trashed. See post #62 in the thread.


    I can always count on you guys to tell the truth.

  7. Do'C October 7, 2007 at 22:23 #

    Hi Rick,

    See post #66 of that very same thread.
    Any answers yet???

  8. notmercury October 7, 2007 at 23:26 #

    Hey, speaking of truth, how’s that methylcobalamin trial going, Rick? 90+% response rate, was it?

  9. Ms. Clark October 8, 2007 at 03:19 #

    I asked Neub on the AS board if he would mind if someone called the Edison, NJ, Fire Dept. safety inspector to see if they’d go check out the Neubrander clinic for safety issues. He didn’t answer, or if he did, I missed his answer. My guess is that they’d prefer that the Fire Dep’t stay away from their “mhbot” schtick.

    The bags have not been tested for use with added oxygen, and the company reassures customers that they’ll never have to deal with oxygen toxicity because the zip up nylon bags **are not supposed to be used with added O2**.

    Since real hbot can kindle seizures, I would like to know what they intend to do for autistic kids if they develop seizures following HBOT or play HBOT of the kind the Neub$ offer.

    I keep wondering how they can in good conscience promote the use of these things (with added O2) which are medical devices that got approval from the FDA for use **without** added O2.

    Rossignol and wife have the same problem with their consciences, it would seem… and Bradstreet and Stoller, too.

  10. Matt October 8, 2007 at 03:20 #


    I am sorry. I honestly didn’t see that post.

    I stopped reading your posts after you made two posts after my question, and neither one addressed the question. When you posted this direct response to my question, I figured you were dodging.


    You did come back 22 posts later with a response.

    Would it be safe to assume it took you a while to check with the manufacturor about the insurance policy?

  11. Ms. Clark October 8, 2007 at 08:04 #

    Oxyhealth’s “insurance” policy would be for use of their Vitaeris 320 (and the other bags) **without** added oxygen. Their website makes it clear that the bags are safe for use with room air… no kidding.

    I want to know what the local fire inspector thinks about the Neub’s clinic. I want to know what home owner insurers think about people putting these things in their homes and using them with oxygen concentrators.

    If they are so safe then why are the parents all talking about having to wear only cotton clothing into the bags? Is this just an exaggerated fear to make them think that there’s a high concentration of oxygen in the bag when in fact they could light a candle inside and not worry a bit because the O2 concentration is so low with the exception of three or four inches in front of the O2 outlet?

    So, Rick, there’s no worry if Dad’s a smoker and he stand next to the bag smoking and talking to mom and junior inside the bag? No worry at all?

    If there’s a significant amount of O2 in there and the pressure is significant then the thing is dangerous, if it’s not dangerous then the pressure and O2 are insignificant… I don’t think Bubba Neubrander and company get to have it both ways.

    I wish the FDA would make a comment on the way these things are being used.

  12. Sullivan October 8, 2007 at 17:04 #


    You know what’s missing on the website for that company? Mention of enriched air or pure oxygen.

    You know that oxyhealth doesn’t sell oxygen enrichment equipment with the chambers? Meybe they are just being nice to the other

    So, the question being “who owns the liability for use of these in an oxygen rich environment” comes up again.

    It would be silly of them to not have liability insurance for the chambers–as they sell them. $5M sounds like a good amount.

    However, it would strike me that a businessman would be just about as silly to accept liability in situations arising from connecting a third party device.

    So, are you saying that if I have an accident in one of these chambers due in part or in whole to connecting an oxygen source to it, that I can expect compensation from Oxyhealth?

  13. Sullivan October 8, 2007 at 17:09 #

    I wish the FDA would make a comment on the way these things are being used.

    You mean besides pointing out that this is not approved?

    Click to access default.pdf

    “Zack was using the chambers to treat autistic and other brain damaged children. The chambers are not approved for these conditions.”

  14. Do'C October 9, 2007 at 04:35 #


    Event Description
    Soft hyperbaric chambers are approved by the fda for the treatment of altitude decompression illness only. This is done by pressurizing with air to approximately 4 psi over ambient pressure. The use of additional oxygen is specifically prohibited by the fda, but is routinely ignored by thousands of users in the united states. In addition, the product has not been approved by the pvho code of the society of mechanical engineers. This approval is specifically required by california and many other states. The soft chambers continued to be marketed and sold by oxy-health corp. Chiropracters in many states are some of the worse offenders by using high flow oxygen to compress, i. E. As a drug.


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