SFU is offering certified divers and pilots the opportunity to experience first-hand the effects of nitrogen narcosis and hypoxia, in Canada’s only civilian research hyper/hypobaric chamber. The project, led by Sherri Ferguson, director of the environmental medicine and physiology unit (EMPU) at SFU, is delving into the effects these have on people.
Nitrogen narcosis is a condition that divers experience as a result of breathing at increasing pressure. “By the time they reach 100 feet, the partial pressures of nitrogen cause a euphoric feeling,” explained Ferguson. “Eventually, if deep enough, it can lead to hallucinations, potentially convulsions and unconsciousness.”
At a much higher elevation, mountain climbers and pilots are also at risk of hypoxia, as the air they are breathing at high altitudes may not supply enough oxygen to the brain. “At high altitude . . . the symptoms are similar to narcosis in that there is impairment and often an unrecognizable impairment” Ferguson explained.
Pilots of pressurized aircraft are at higher risk because at very high altitudes, between 25,000 to 30,000 feet. Ferguson said, “If they were to lose cabin pressure . . . within three to five minutes they are no longer able to make useful decisions.”
To simulate these extreme conditions and allow those at risk to experience the effects of hypoxia — which causes a dazed, drunken sensation — the Burnaby campus lab is equipped with two chambers, one of top of the other. The top chamber is used for hypoxia and the lower one for nitrogen narcosis, and may accommodate up to six people at a time. The upper chamber is kept dry, while the lower chamber can be filled with up to 2,500 gallons of fresh water.
“If [a pilot] were to lose cabin pressure . . . within three to five minutes they are no longer able to make useful decisions.”
-Sherri Ferguson,
director, Environmental Medicine and Physiology Unit
Participants trying out the chambers so far have feature a range of different groups within the aviation and diving community. “The high altitude is being used by flight schools and airlines are training their pilots to high altitude and hypoxia awareness,” said Ferguson. “We are open to certified divers but many dive shops and dive clubs are booking us right now.”
The common citizen needs a diving certificate to book sessions in the chamber, , while pilots or flight students are ableto book through their airline or flight school. The increasing popularity of the opportunity has resulted in an expansion of the research linked to use of the chamber.
The chamber may also play host to clinical trials involving hypobaric oxygen. Ferguson explained: “Breathing the oxygen under pressure is a form of medicine as well . . . There are 14 indicators that physicians will treat in a [hypobaric] chamber.” Injuries such as burns, carbon dioxide poisoning, diabetic ulcers, radiation narcosis and non-healing wounds may be treated using a hypobaric chamber.
The project is also open to a new area of research involving pressurized, hypobaric oxygen in the possible treatment of children with autism or people with Crohn’s disease. This new interest stems from reports by operators of hypobaric chambers not overseen by physicians on the effects on people suffering from these diseases.
“Some of the research that we do in here is to do proper, randomized, controlled, clinical trials, so we can look and see whether or not that [treatment] is effective,” said Ferguson. The healing process of some of these indicators is still a mystery, as it is done in the process of narcosis in the brain.
Looking forward, a researcher from the US Navy is set to start work with Sherri Ferguson and her unit next year to explore the effect of hypobaric treatment on the brain and stroke victims in particular.
Ferguson concluded, “If we can understand the mechanism more then we can maybe expand what we use it for . . . I would really like to see in brain neurons what is happening under pressure.”
