The so-called “mild hyperbaric” chambers achieve a maximum pressure of 1.4 ATA (Atmosphere’s absolute) which is the equivalent of being about 13 feet deep in the ocean. They continue to proliferate at a seemingly unprecedented rate on the strength of promoting wholly unproven, and in many cases implausible, benefits to desperate (or gullible) people. If the problem were limited to that of taking money from patients under questionable pretenses, we would not be so worried. The problem is the possibility of real injury from these devices about which patients are completely unaware. The way that these chambers are used exposes unwary patients to the risk of injury or death from a chamber fire, as well as injury or death from an explosive decompression. We need to alert people to these risks.
Most commonly, these chambers are of a soft-walled inflatable design but there are hard-shelled low-pressure versions out there as well. Inflatable hyperbaric chambers are approved by the FDA based on their being “substantially equivalent” to the air-filled Gamow (pronounced “Gam-ov”) Bag, pictured above. FDA approval for their use is limited to treatment of “Acute Mountain Sickness (AMS) and its associated mild symptoms.” Mild hyperbaric chamber operators further violate FDA approval when they incorporate an oxygen breathing system. The Gamow bags are pressurized with air, but these inflatable chambers are often being used with an oxygen concentrator that provides about 95% oxygen for pressurization. They have no oxygen sensors to monitor the oxygen accumulating in the chamber. Patients inside the chambers are often allowed to use cell phones and computers, so fire is a real risk due to the increased oxygen environment. Additionally, the extra oxygen is dumped into the room where the inflatable bag is housed – without attention to any fire safety precautions in the room. The plastic bags can also rupture, immediately depressurizing the patient and possibly causing an arterial gas embolism (AGE). Even though a pressure equivalent to 13 feet of sea water may not seem very “deep,” people have died or suffered an AGE from an even lower pressure differential. It’s also common for more than one person to be “treated” at a time in these chambers, another FDA violation, and one company even manufacturers a four-person capability chamber.
Following a recent and concerted educational effort, State and Local Fire Marshals have begun closing the businesses that promote mild hyperbaric oxygen therapy due to non-compliance with National Fire Protection (NFPA 99) Chapter 14 standards. The purveyors of these “mild hyperbaric” chambers have attempted to justify their lack of compliance with fire safety standards by saying that the chambers are used for “therapeutic” and not “medical” purposes. However, it’s obvious that they are promoted as a medical treatment for a long list of conditions (none of which are remotely related to acute mountain sickness). One such company even approached the NFPA Hyperbaric Facilities Technical Committee with a request that they create a different fire safety standard on the specious argument that they are not used for “medical” purposes. (As if the risk associated with an oxygen fire is somehow related to the purpose of a treatment!) Thankfully, the committee voted unanimously to reject proposals to create some new safety standard for inflatable chambers.
We appreciate the action of the American Medical Association which, in the week prior to the NFPA meeting, formally opposed the use of the mild hyperbaric therapy.
President, National Baromedical Services
President, National Board of Diving & Hyperbaric Medical Technology