Do passengers get enough oxygen?

[Guest guest]

http://www.usatoday.com/news/nation/2001-03-05-oxygen.htm

03/05/2001 - Updated 10:55 PM ET

Do passengers get enough oxygen?

By , USA TODAY

As the number of reported heart attacks, faintings and other medical

emergencies aboard airlines continues to soar, the government is considering

changing the way cabins are pressurized to provide more oxygen to

passengers.

The Federal Aviation Administration and scientists across the industry are

reevaluating a standard that was set decades ago and based on studies of

healthy servicemen in altitude chambers. The modern airline cabin looks very

different, as aging baby boomers - many with health problems that can worsen

suddenly and sometimes fatally - fly farther and longer than ever before.

There is plenty of oxygen in the air inside airline cabins. But because the

barometric pressure is lower - equivalent to standing on an 8,000-foot

mountain - not as much oxygen reaches the bloodstream to be carried to vital

organs. Much of the focus on cabin air quality has been on the spread of

viruses such as the common cold. But a new focus is emerging as scientists

and doctors learn more about the threat that affects every airline

passenger: hypoxia, the term for too little oxygen.

This lack of oxygen usually causes little more than a headache and a feeling

of fatigue in the average healthy flier. But passengers who have an

underlying breathing, heart or circulatory problem - even one they don't yet

know exists - can suffer serious medical emergencies when the oxygen level

drops. Heart attacks are among the more serious problems that hypoxia could

cause during airline flights.

" People are traveling to all ends of the Earth and very little attention has

been given to the impact and the insult on the human body during flight, "

says n B. Sides, a vice president of the Aerospace Medical Association.

As a military researcher, she has studied the drop in oxygen levels at

cruising altitudes.

" Ten to 15 years ago, we were concerned about smoking on airlines. Now this

is the next level of concern, " Sides says. " Going on an aircraft does in

fact compromise one's rate of oxygenation. The oxygen deficits are

significant. "

While aviation experts reconsider - sometimes skeptically - the cabin

pressure standards, the National Academy of Sciences has appointed a panel

of medical experts to determine the exact health risks of breathing cabin

air. The effort, which is expected to be completed this year, comes as the

number of reported medical emergencies aboard airliners is increasing.

The FAA does not track the number of medical emergencies in the air, but

MedAire, a Phoenix-based company that connects doctors with flight crews and

ill passengers in flight, says medical emergencies are at an all-time high.

In the mid-1980s, there were about 10 deaths each year on U.S. airliners.

Now, industry officials estimate, as many as 100 people a year die because

of medical problems during flights. MedAire hears about many of them: The

company helps 35 airlines around the world and took 8,500 medical calls last

year.

Aviation experts say in-depth studies would be needed to determine if the

hypoxia at cruise altitude is to blame for the medical emergencies. But

doctors atMedAire are suspicious. They say that 21% of the calls they get

are for passengers who pass out. Heart and breathing problems accounted for

12% and 11%, respectively.

" The issue of hypoxia is really significant for people with heart or lung

disease, and no one knows it, " says Brent Blue, a doctor and pilot who sells

oxygen-measuring devices.

A drop in oxygen

Here's why the body begins losing oxygen within minutes at cruising

altitudes:

As the plane soars, extremely hot air is drawn from the jet's engines,

cooled and piped into the cabin. This constant flow of very dry air keeps a

life-sustaining pressure in the cabin. But because the plane is designed to

be as lightweight as possible, it can only withstand so much pressure. The

thin aluminum shell of most jets expands like a balloon - as much as an

inch - as the pressure inside increases and the outside pressure decreases

at high altitudes.

There is just as much oxygen in the cabin air at cruising altitude as on the

ground, but because the atmospheric pressure is lower than at sea level, it

is more difficult for the body to absorb the vital gas. With less pressure,

fewer oxygen molecules cross the membranes in the lungs and reach the

bloodstream.

The result is a significant drop in the amount of oxygen in the blood -

anywhere from 5% to 20% depending on the person, the plane and the length of

the flight.

With less oxygen in the bloodstream, the vital organs soon get deprived.

The reduced oxygen supply to the brain is why some suffer headaches while in

flight, one of the symptoms of hypoxia. When oxygen levels fall in the

brain, the heart tries to compensate by beating harder and faster. Another

symptom of hypoxia is fatigue.

But doctors say the body's efforts to compensate can hurt people who fly

with underlying medical conditions.

" Many papers report that the rate of in-flight medical emergencies is higher

in cases with cardiovascular or cerebrovascular disorders, " says Makoto

Matsumura, of the Heart Institute at Saitama Medical School in Japan, who

presented new details about the issue at last year's American Heart

Association meeting. " The hypoxia is related to the cabin environment.

Therefore, it is important to draw attention to the aged and the patients

with hypertension who potentially have a vascular disorder. "

Joan Sullivan Garrett, who runs MedAire, suspects that many of their medical

emergencies are from passengers whose bodies are already weakened by

diseases struggling to compensate for a shortage of oxygen.

" In a lot of these, the impetus is some sort of hypoxia, " she says. " When

you step back and look at the average traveler, they are older and many have

health problems before they ever step on a plane. "

Time for a new standard?

Because the pressure in an airliner is easy to control, the industry is

considering whether it should change the minimum pressure standards to try

to prevent medical emergencies.

An FAA rule requires pilots to keep jets pressurized to the level that is

equivalent to an 8,000-foot mountain or lower. The rule, FAA officials say,

is based on altitude chamber tests performed on healthy airmen decades ago.

But the FAA says it does not monitor planes to see how they are pressurized

while carrying passengers.

One study performed by doctors in the 1980s found pressurization differences

across the fleet.

Each plane must meet the same strict standard to go into service. But once

it is in use, everyday wear and tear can change the way the air flows in the

cabin. Even small dents in the floor by the door, where heavy carts are

dragged aboard, can make it more difficult to maintain cabin pressure.

The more air the pilot takes from the engines to pressurize the cabin,

however, the more fuel it takes to fly. The air also reduces the engine's

thrust.

" These planes are flying up to 42,000 feet, " says Stanley Mohler of

State University School of Medicine in Dayton, Ohio, who has studied the

health effects of flight. " When you get up to that area, it takes a lot of

fuel to keep the cabin pressurized. "

As engineers consider whether the atmosphere inside the cabin could be

required to be kept at pressurization equal to 6,000 feet, for instance, to

increase passenger oxygenation, the airlines want proof that a change is

needed.

" The airlines are going to resist, " Mohler says. " If you lower the cabin

pressure on many of their airline flights, you're going to burn a lot more

fuel. "

The aviation industry says that while it is worth studying, there is not yet

any proof that changing the pressure will help passengers.

" You have to have some evidence that it's going to be salutary to the

passengers, " says Rayman of the Aerospace Medical Association.

He calls the FAA's 8,000-foot rule " rather arbitrary " and " a best guess, "

but he says there is no proof that lowering it would help. " There is no

evidence and I think it will be very difficult to get it. "

Some people in the industry balk at the idea of changing the rules to meet

the needs of people with health problems.

" I feel sorry for somebody who has vascular problems or breathing problems,

but maybe they shouldn't be flying, " says Dave Heekin, an airline captain.

" If you are going to make it comfortable for the most susceptible passengers

you're going to have an airplane that you're not going to be able to fly.

" I have compassion for them but you can't do everything to the lowest common

denominator. "

Who's responsible?

Heekin hopes his passengers begin to take more responsibility for their

health. " I'm tired of the flight attendants telling me we have a passenger

with breathing problems and we may have to land in Omaha, " Heekin says.

Garrett of MedAire says the responsibility shouldn't rest with the airlines,

which can't know their passengers' medical baggage.

" I feel sorry for the airlines, " she says. " There is no way the airlines can

possibly prepare to deal with the kinds of problems and the critical nature

of the problems travelers have today. How can they be responsible? They

don't know that my Aunt Agnes smokes. "

Doctors who have studied the problem agree.

They say two common factors that cause hypoxia are often launched on the

ground as passengers prepare to board the plane.

When people drink too much alcohol, the body does not use oxygen as

efficiently, leading to what is known as histotoxic hypoxia. And cigarette

smoke damages the fragile membranes in the lung where oxygen is exchanged.

People who have smoked for years and who smoke several cigarettes before a

flight can suffer what is known as hypemic hypoxia before they board the

plane.

Flight attendants say they keep an eye on the " runners " who drink and smoke

in the airport bar until the last moments of boarding, then run to catch the

plane before it leaves the gate.

" When they get on board they decompensate, " says Garrett, who was a flight

nurse before starting MedAire. " They get chest pain and in some cases they

will have a cardiac arrest. "

Blue, a Hole, Wyo., physician and pilot, says alcohol is a major

reason for so many medical emergencies in flight.

" Alcohol should not be served on an airplane, " he says. " I can't think of

anything worse you could do on an airplane than drink. "

Blue has a Web site - Aeromedix.com - with information about hypoxia in

flight. And he sells fingertip devices that measure oxygen level in the

blood. He began selling to pilots so they could monitor themselves while

flying their private planes. But he says thousands of airline travelers have

bought the devices, which cost $380, in recent years.

If a healthy passenger suffers any ill effects from hypoxia, it may be

anything from a headache to tingling lips to weakness or other annoyances.

" But if they have a bad cold or upper respiratory infection, walking

pneumonia, coronary artery disease, emphysema, a lot of those things,

they'll notice it, " Blue says. " Especially with coronary artery disease they

will be at significant risk. "

He says the airlines should not be " let off the hook " because they do not

give any warning to their passengers today about hypoxia or cabin

pressurization.

" They can say this flight will be 8,000 feet or 7,500 feet, " he says. " Then

you could make a choice. "

Rayman, a physician on the National Academy of Sciences committee on cabin

air quality, offers this perspective: " People with coronary artery disease

are flying every day. The great majority reach their destination none the

worse. Those with advanced or significant coronary artery disease are at

increased risk and should accordingly consult their physicians before

planning to travel by air. "

[Guest guest]

It just goes to show - you learn something new everyday!

Barbara

From: " Doug Walkinshaw " <dsw@...>

" bherk " <bherk@...>

Sent: Tuesday, March 06, 2001 8:56 AM

Subject: Re: Do passengers get enough oxygen?

: Barbara,

:

: The cabin pressure is 8,000 ft elevation of 3/4 atmosphere. Sea level is

: one atmosphere.

:

: Take a look at the UK CAA warning under Section 3. Incapacitation

: Procedures,

: about cockpit air conditioner toxic fumes on the web. The URL address is:

:

: http://www.srg.caa.co.uk/documents/Fodcoms/Fodc17-00.PDF

:

: Doug

:

: ******************************************

: S. Walkinshaw PhD, PEng

: Indoor Air Technologies Inc.

: (613) 731-2559 Fax: (613) 737-2005

: e-mail: dsw@...

: web: www.indoorair.ca

[Guest guest]

Look to alaska Airlines and their employees union for the cause of the illness.

Several flight attendants chemically injured by burning hydraulic fluid

vapors.This type of thing is the source of passengers getting sick. Quit blaming

the

elderly for being old and more subject to death from poisoning. Lots of people

are getting permanantly

injured while the smoke screen is thrown out by airlines in a big cover

up.Sickening actually what big companies do in an attempt to cover their butts

and avoid responsibility.

Who would know more about what is happening than the attendents and mechanics

who are there

every day. If you own stock in alaska you should sell it they are going down.

----------

> http://www.usatoday.com/news/nation/2001-03-05-oxygen.htm

>

> 03/05/2001 - Updated 10:55 PM ET

>

> Do passengers get enough oxygen?

>

> By , USA TODAY

>

> As the number of reported heart attacks, faintings and other medical

> emergencies aboard airlines continues to soar, the government is considering

> changing the way cabins are pressurized to provide more oxygen to

> passengers.

>

> The Federal Aviation Administration and scientists across the industry are

> reevaluating a standard that was set decades ago and based on studies of

> healthy servicemen in altitude chambers. The modern airline cabin looks very

> different, as aging baby boomers - many with health problems that can worsen

> suddenly and sometimes fatally - fly farther and longer than ever before.

>

> There is plenty of oxygen in the air inside airline cabins. But because the

> barometric pressure is lower - equivalent to standing on an 8,000-foot

> mountain - not as much oxygen reaches the bloodstream to be carried to vital

> organs. Much of the focus on cabin air quality has been on the spread of

> viruses such as the common cold. But a new focus is emerging as scientists

> and doctors learn more about the threat that affects every airline

> passenger: hypoxia, the term for too little oxygen.

>

> This lack of oxygen usually causes little more than a headache and a feeling

> of fatigue in the average healthy flier. But passengers who have an

> underlying breathing, heart or circulatory problem - even one they don't yet

> know exists - can suffer serious medical emergencies when the oxygen level

> drops. Heart attacks are among the more serious problems that hypoxia could

> cause during airline flights.

>

> " People are traveling to all ends of the Earth and very little attention has

> been given to the impact and the insult on the human body during flight, "

> says n B. Sides, a vice president of the Aerospace Medical Association.

> As a military researcher, she has studied the drop in oxygen levels at

> cruising altitudes.

>

> " Ten to 15 years ago, we were concerned about smoking on airlines. Now this

> is the next level of concern, " Sides says. " Going on an aircraft does in

> fact compromise one's rate of oxygenation. The oxygen deficits are

> significant. "

>

> While aviation experts reconsider - sometimes skeptically - the cabin

> pressure standards, the National Academy of Sciences has appointed a panel

> of medical experts to determine the exact health risks of breathing cabin

> air. The effort, which is expected to be completed this year, comes as the

> number of reported medical emergencies aboard airliners is increasing.

>

> The FAA does not track the number of medical emergencies in the air, but

> MedAire, a Phoenix-based company that connects doctors with flight crews and

> ill passengers in flight, says medical emergencies are at an all-time high.

> In the mid-1980s, there were about 10 deaths each year on U.S. airliners.

>

> Now, industry officials estimate, as many as 100 people a year die because

> of medical problems during flights. MedAire hears about many of them: The

> company helps 35 airlines around the world and took 8,500 medical calls last

> year.

>

> Aviation experts say in-depth studies would be needed to determine if the

> hypoxia at cruise altitude is to blame for the medical emergencies. But

> doctors atMedAire are suspicious. They say that 21% of the calls they get

> are for passengers who pass out. Heart and breathing problems accounted for

> 12% and 11%, respectively.

>

> " The issue of hypoxia is really significant for people with heart or lung

> disease, and no one knows it, " says Brent Blue, a doctor and pilot who sells

> oxygen-measuring devices.

>

> A drop in oxygen

>

> Here's why the body begins losing oxygen within minutes at cruising

> altitudes:

>

> As the plane soars, extremely hot air is drawn from the jet's engines,

> cooled and piped into the cabin. This constant flow of very dry air keeps a

> life-sustaining pressure in the cabin. But because the plane is designed to

> be as lightweight as possible, it can only withstand so much pressure. The

> thin aluminum shell of most jets expands like a balloon - as much as an

> inch - as the pressure inside increases and the outside pressure decreases

> at high altitudes.

>

> There is just as much oxygen in the cabin air at cruising altitude as on the

> ground, but because the atmospheric pressure is lower than at sea level, it

> is more difficult for the body to absorb the vital gas. With less pressure,

> fewer oxygen molecules cross the membranes in the lungs and reach the

> bloodstream.

>

> The result is a significant drop in the amount of oxygen in the blood -

> anywhere from 5% to 20% depending on the person, the plane and the length of

> the flight.

>

> With less oxygen in the bloodstream, the vital organs soon get deprived.

>

> The reduced oxygen supply to the brain is why some suffer headaches while in

> flight, one of the symptoms of hypoxia. When oxygen levels fall in the

> brain, the heart tries to compensate by beating harder and faster. Another

> symptom of hypoxia is fatigue.

>

> But doctors say the body's efforts to compensate can hurt people who fly

> with underlying medical conditions.

>

> " Many papers report that the rate of in-flight medical emergencies is higher

> in cases with cardiovascular or cerebrovascular disorders, " says Makoto

> Matsumura, of the Heart Institute at Saitama Medical School in Japan, who

> presented new details about the issue at last year's American Heart

> Association meeting. " The hypoxia is related to the cabin environment.

> Therefore, it is important to draw attention to the aged and the patients

> with hypertension who potentially have a vascular disorder. "

>

> Joan Sullivan Garrett, who runs MedAire, suspects that many of their medical

> emergencies are from passengers whose bodies are already weakened by

> diseases struggling to compensate for a shortage of oxygen.

>

> " In a lot of these, the impetus is some sort of hypoxia, " she says. " When

> you step back and look at the average traveler, they are older and many have

> health problems before they ever step on a plane. "

>

> Time for a new standard?

>

> Because the pressure in an airliner is easy to control, the industry is

> considering whether it should change the minimum pressure standards to try

> to prevent medical emergencies.

>

> An FAA rule requires pilots to keep jets pressurized to the level that is

> equivalent to an 8,000-foot mountain or lower. The rule, FAA officials say,

> is based on altitude chamber tests performed on healthy airmen decades ago.

>

> But the FAA says it does not monitor planes to see how they are pressurized

> while carrying passengers.

>

> One study performed by doctors in the 1980s found pressurization differences

> across the fleet.

>

> Each plane must meet the same strict standard to go into service. But once

> it is in use, everyday wear and tear can change the way the air flows in the

> cabin. Even small dents in the floor by the door, where heavy carts are

> dragged aboard, can make it more difficult to maintain cabin pressure.

>

> The more air the pilot takes from the engines to pressurize the cabin,

> however, the more fuel it takes to fly. The air also reduces the engine's

> thrust.

>

> " These planes are flying up to 42,000 feet, " says Stanley Mohler of

> State University School of Medicine in Dayton, Ohio, who has studied the

> health effects of flight. " When you get up to that area, it takes a lot of

> fuel to keep the cabin pressurized. "

>

> As engineers consider whether the atmosphere inside the cabin could be

> required to be kept at pressurization equal to 6,000 feet, for instance, to

> increase passenger oxygenation, the airlines want proof that a change is

> needed.

>

> " The airlines are going to resist, " Mohler says. " If you lower the cabin

> pressure on many of their airline flights, you're going to burn a lot more

> fuel. "

>

> The aviation industry says that while it is worth studying, there is not yet

> any proof that changing the pressure will help passengers.

>

> " You have to have some evidence that it's going to be salutary to the

> passengers, " says Rayman of the Aerospace Medical Association.

>

> He calls the FAA's 8,000-foot rule " rather arbitrary " and " a best guess, "

> but he says there is no proof that lowering it would help. " There is no

> evidence and I think it will be very difficult to get it. "

>

> Some people in the industry balk at the idea of changing the rules to meet

> the needs of people with health problems.

>

> " I feel sorry for somebody who has vascular problems or breathing problems,

> but maybe they shouldn't be flying, " says Dave Heekin, an airline captain.

> " If you are going to make it comfortable for the most susceptible passengers

> you're going to have an airplane that you're not going to be able to fly.

>

> " I have compassion for them but you can't do everything to the lowest common

> denominator. "

>

> Who's responsible?

>

> Heekin hopes his passengers begin to take more responsibility for their

> health. " I'm tired of the flight attendants telling me we have a passenger

> with breathing problems and we may have to land in Omaha, " Heekin says.

>

> Garrett of MedAire says the responsibility shouldn't rest with the airlines,

> which can't know their passengers' medical baggage.

>

> " I feel sorry for the airlines, " she says. " There is no way the airlines can

> possibly prepare to deal with the kinds of problems and the critical nature

> of the problems travelers have today. How can they be responsible? They

> don't know that my Aunt Agnes smokes. "

>

> Doctors who have studied the problem agree.

>

> They say two common factors that cause hypoxia are often launched on the

> ground as passengers prepare to board the plane.

>

> When people drink too much alcohol, the body does not use oxygen as

> efficiently, leading to what is known as histotoxic hypoxia. And cigarette

> smoke damages the fragile membranes in the lung where oxygen is exchanged.

>

> People who have smoked for years and who smoke several cigarettes before a

> flight can suffer what is known as hypemic hypoxia before they board the

> plane.

>

> Flight attendants say they keep an eye on the " runners " who drink and smoke

> in the airport bar until the last moments of boarding, then run to catch the

> plane before it leaves the gate.

>

> " When they get on board they decompensate, " says Garrett, who was a flight

> nurse before starting MedAire. " They get chest pain and in some cases they

> will have a cardiac arrest. "

>

> Blue, a Hole, Wyo., physician and pilot, says alcohol is a major

> reason for so many medical emergencies in flight.

>

> " Alcohol should not be served on an airplane, " he says. " I can't think of

> anything worse you could do on an airplane than drink. "

>

> Blue has a Web site - Aeromedix.com - with information about hypoxia in

> flight. And he sells fingertip devices that measure oxygen level in the

> blood. He began selling to pilots so they could monitor themselves while

> flying their private planes. But he says thousands of airline travelers have

> bought the devices, which cost $380, in recent years.

>

> If a healthy passenger suffers any ill effects from hypoxia, it may be

> anything from a headache to tingling lips to weakness or other annoyances.

> " But if they have a bad cold or upper respiratory infection, walking

> pneumonia, coronary artery disease, emphysema, a lot of those things,

> they'll notice it, " Blue says. " Especially with coronary artery disease they

> will be at significant risk. "

>

> He says the airlines should not be " let off the hook " because they do not

> give any warning to their passengers today about hypoxia or cabin

> pressurization.

>

> " They can say this flight will be 8,000 feet or 7,500 feet, " he says. " Then

> you could make a choice. "

>

> Rayman, a physician on the National Academy of Sciences committee on cabin

> air quality, offers this perspective: " People with coronary artery disease

> are flying every day. The great majority reach their destination none the

> worse. Those with advanced or significant coronary artery disease are at

> increased risk and should accordingly consult their physicians before

> planning to travel by air. "

>

>

>

>

>

>