notam2

There was a suspected case of hypoxia on a Canjet flight from Fredericton to Puerto Plata earlier this month:

http://www.cbc.ca/canada/new-brunswi...woman-711.html

I guess I can understand that happening since cabins are only pressured to 8000 feet when at altitude, especially if there was a pre-existing medical condition, but the scary part is that the passenger claims that several other passengers fainted as well!

tcook052

Note that the CBC article doesn't make the claim it was a case of hypoxia and only says:

Wilkins said she still isn't sure what caused her to pass out on the plane, but she said a couple of other passengers fainted as well.

CBC contacted CanJet to see whether they could provide any more details, but the airline did not return the calls.

Now the thread title might be more correct if it said it was a suspected case of hypoxia but until there's more concrete evidence I wouldn't agree with OP's very definate thread title. Just MHO.

gglave

Am I the only one who sees the black humour in a story about a flight with air pressure problems bound for 'pop' ?

B1

This can't be hypoxia - there is plenty of oxygen at that pressure and it was half way through the flight. The person could have had any number of problems and full-on oxygen helps recovery. The others fainting is the result of panic when they see the event and react out of fear.

notam2

I did some research after reading this story and its possible to get hypoxia at moderate altitudes (approx 6000 feet) if you have COPD or some other pulmonary disease that results in a lower than normal amount of oxygen in one's blood. Since cabins are pressurized to 8000 feet when at altitude, its possible that there was no malfunction but the pax still got hypoxia....or it could have been something else too....

B1

Hypoxia means that there is not enough oxygen available from the atmosphere and this has to do with oxygen getting into the red blood cells. COPD is a lung/breathing problem that can happen at any altitude. The decrease in oxygen at 8000 feet is simply not enough to cause hypoxia - the same problem would occur at sea level for such a person. If this was reported as hypoxia induced by the altitude it would merit a publication in medical archives. It would mean that the person could not drive through the passes west of Denver. People should be calm about this.

tcook052

No heavy breathing, you mean?

BTW I appreciate OP modifying the thread title to at least more correctly call this a case of suspected hypoxia, though even that suspicion hasn't been borne out with any great degree of probability.

Doc Savage

Sorry, this is wrong. People with COPD certainly can and do get hypoxic at altitude. The partial pressure of O2 is less at altitude. Consider the person who is borderline for maintaining adequate oxygenation at sea level. When they experience a significantly lower partial pressure at altitude, either in a car over a mountain pass or in a plane at 8000 feet equivalent, they can no longer maintain adequate oxygenation.

I did my medical training in Denver, and we had a whole lot more people there who required supplemental O2 than we do at sea level where I practice now.

From this story, it sounds much more like vasovagal fainting or panic attack to me in any case. Don't know where anyone is getting the "hypoxia" stuff from.

notam2

Much thanks for the technical explanation.

I guess why I was thinking hypoxia is because several pax were reported as having fainted. Personally, if I'm on a plane and I see one pax faint, I'm not going to freak out -- I'd just think they've got a fear of flying, health problem, etc. But when multiple passengers faint, I start thinking there has to be a common cause -- food, water, the air, etc. While I concede this is entirely speculation, if I was on a flight and 10-ish people around me past out...and the oxygen masks didn't come down....you'll have to excuse me if I don't leave a stain behind on my seat....

B1

For those who care, we learn this from the UK NHS:
"Pink puffers and blue bloaters
In normal people the respiratory drive is largely initiated by PaCO2 but in COPD hypoxia can be a strong driving force and so if this is corrected the respiratory drive will be reduced. Patients with COPD have traditionally been divided into pink puffers and blue bloaters based on their physiological response to abnormal blood gases.The former work hard to maintain a normal pO2 which is why they puff away. They tend to have a barrel-shaped, hyperinflated chest and breath through pursed lips. The latter are blue because of hypoxia and polycythaemia. They are often obese and have water retention. This is why they are bloated. The blue bloaters are dependent upon hypoxia for their respiratory drive and to give oxygen and deprive them of this will lead to signficant hypercapnia and acid base imbalance. Although this concept is widely taught and acknowledged academically, in clinical practice patients tend not to be clearly in one or the other of these two categories."