Medal Winners: Air Traffic Control Tapes

On pumped fuel gases: Point well taken, you're correct that it used to
be at least partly carbon monoxide. I think that industrial fuel gases
were even purer CO at one time. I have a vague memory that it was
produced by passing flue gases through heated iron pipes to convert CO2
to CO--is that correct?

On helium solubility: Thanks for the note, I wasn't aware of Trimix.
Similarly, I didn't know helium had a drug effect. Xenon must have the
most of all the noble gases; it has good anesthetic effect at about 70
Torr and is currently being proposed for actual surgical anesthesia. It
has the interesting problem of not being patentable, and therefore not
worth any company's money to get through FDA approval, so it may never
appear on the drug market. Of other small, nonpolar molecules, the one
I'm sorry I missed (it was gone before I started my practice) is
cyclopropane. It's similarly very blood insoluble and therefore
fast-acting (more on that if anyone's interested). It has the problem
of being not just inflammable like ether, but explosive. Spark
suppression used to be a big deal in operating room design.

Another interesting suicide-by-oxygen-dilution problem is automobile
exhaust. Catalytic converters work well enough that running a car
engine in a closed garage frequently produces anoxic brain damage (CO2
poisoning) rather than death (CO same). Perhaps that happens to some of
the suicides who are unaware that fuel gas got swapped for methane.

Things were quiet in the operating room today, and I had an hour to chat
with the anesthesiology residents. I told them about this Usenet
discussion and asked them to distinguish CO2 poisoning from that by CO.
They didn't do very well.

David

Don W wrote:
Hi David,

David Kazdan wrote:

Helium is almost exactly the dilutional asphyxiant that nitrogen
is. It's used in deep-diving artificial atmospheres for two reasons:
Nitrogen is a weak anesthetic gas, producing intoxication at several
atmospheres pressure--(nitrogen narcosis"), and it's soluble enough in
blood and other water-based body fluids to fizz out when the pressure
is released suddenly (the bends, caisson worker's disease). "Helium
has neither of these properties."


snip

David


David Kazdan, MD, PhD
Anesthesiologist
Pilot

I hesitate to enter this discussion since you are obviously well
qualified, however, that is often how learning occurs and I still
have a lot to learn.

I agree with all of your excellent post with one minor exception.
Helium _is_ absorbed into the bloodstream under high enough partial
pressure and does release bubbles when the pressure is released
too quickly. Heliox (Helium + O2) and Trimix (Helium + N + O2) are
common gasses used in the technical diving community, and they both
require decompression stops on the way back to the surface. Technical
divers use these mixes for dives from 130' (~5 atmospheres) to as much
as 1000' (~31 atmospheres). The O2 content of the mixes is reduced to
avoid oxygen toxicity effects at high PPO2. I also would point out
that helium at high PP--although not narcotic like Nitrogen--does
produce some strange physiological effects including a "buzz" similar
to having had a lot of caffein.

Don Woodbridge P.E.
Engineer
Technical Diver
Pilot

On Tue, 7 Feb 2006 12:12:29 -0600, "Montblack"
wrote:

("Don W" wrote)
I also would point out that helium at high PP--although not narcotic like
Nitrogen--does produce some strange physiological effects including a
"buzz" similar to having had a lot of caffein.

Don Woodbridge P.E.
Engineer
Technical Diver
Pilot


This may sound silly, but what about CO2 in soda-pop? If one drinks six or
seven cans/day of pop (diet - whatever) what does that do in the
bloodstream?

I've heard Olympic level athletes do not drink pop, for performance
reasons - blood, oxygen carrying ability, ...something.

It's loaded with processed sugar which brings on a shot of energy
followed by a rapid decline in energy. They want something that
lasts. You ever see how much some of those athletes eat? If I ate
half that much I'd need wheels.

Pop is often refered to as having "empty calories". People who drink a
lot of pop tend to be a wee bit on the hefty side and it takes a lot
of exercise to burn that off..

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Montblack

On 7 Feb 2006 10:08:43 -0800, wrote:


Roger wrote:
On 6 Feb 2006 11:40:13 -0800, wrote:


Roger wrote:
On Sun, 05 Feb 2006 17:50:04 GMT, Richard Lamb
wrote:

Might we go a bit farther?

The reason I ask is that I've seen people take big lungfuls of Helium,
which (obviously) doesn't produce the same effect.

A really big lung full can make you light headed in a hurry, but
beyond that?


Can someone explain why N is such a disaster but He doesn't?

"I think" it has to do with the partial pressure of He compared to N,
but I really don't know.

Partial Pressure of a gas is what the pressure would be if all the
other gasses were removed without changing the volume.

Equal volumes of gas at the same temperature and pressure have
equal numbers of molecules (Avogadro's law). So no, that isn't
the explanation.

I thought Avogadro's Law (number the same?) was a gram molecular
weight of any element will have the same number of molecules as the
gram molecular weight for any other element. As I recall it's
6 X 10^28


Perhaps he has more than one law named for him.

In essence, Avogadro's number is the conversion factor between
gram molecular weight of an and the number of molecules
in a sample of that element with a mass numerically equal in grams
to its gram molecular weight. Which, as stated in the law you quote,
is the same for all elements, or for that matter any substance which
consists of but a single molecule.

6.022 E23, as I recall.

Avogadro's law, Boyle's law and Charles' law may be combined to
produce the ideal gas law.

Back in college we had two chemistry books that had exponents on that
that differed by several digits.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

"David Kazdan" wrote in message
news

Things were quiet in the operating room today, and I had an hour to chat
with the anesthesiology residents. I told them about this Usenet
discussion and asked them to distinguish CO2 poisoning from that by CO.
They didn't do very well.

I remember attempting to resuscitate a V. Fib. case at a fraternity near the
U. of Wash. We tubed the patient but were unable to get an IV line going to
administer meds. I was about to try a subclavian when three anestheologists
walked up.

It's been over thirty years ago and I scarcely remember the details, but
they quickly advised us that we already had a perfect administration route -
the endotracheal tube! We had never been instructed that we could administer
drugs through the tube. After checking to make sure they were who they
claimed to be, they assisted us by simply squirting meds in the tube and
resuming bag respiration.

The attempt was futile, but I still remember their help.

Rich S.

("Roger" wrote)
I've heard Olympic level athletes do not drink pop, for performance
reasons - blood, oxygen carrying ability, ...something.

It's loaded with processed sugar which brings on a shot of energy followed
by a rapid decline in energy. They want something that lasts. You ever
see how much some of those athletes eat? If I ate half that much I'd need
wheels.


No, not the sugar or diet chemicals, just the CO2 side of the can. Does
drinking 5, 6, 7, 8, 9 cans of pop per/day do something (bad) to your system
because of (possible?) CO2 absorption(?) into the bloodstream?

The Olympics are days away...
(Getting back OT with medal winners :-)


Montblack

Montblack wrote:

Monty, did you get a note from me today?
If not, I obviously didn't clean up your email address right.

Some of us are better manglers than others....


Richard

("Richard Lamb" wrote)
Monty, did you get a note from me today?
If not, I obviously didn't clean up your email address right.

Some of us are better manglers than others....


Nope.



Y4-NOT = Mont black at v i s i (.) and the rest


Montblack :-)
O-ho, the Wells Fargo Wagon is a-comin' down the street
I wish, I wish I knew what it could be

It is CO that is the poison!!!

Read somewhere that there are no toxic substances, only toxic
quantities.

Right--give higher doses and _never_ give bicarbonate that way (mostly
off the ACLS protocols, anyway). It's mostly used for epinephrine doses.

David

Rich S. wrote:
"David Kazdan" wrote in message
news
Things were quiet in the operating room today, and I had an hour to chat
with the anesthesiology residents. I told them about this Usenet
discussion and asked them to distinguish CO2 poisoning from that by CO.
They didn't do very well.


I remember attempting to resuscitate a V. Fib. case at a fraternity near the
U. of Wash. We tubed the patient but were unable to get an IV line going to
administer meds. I was about to try a subclavian when three anestheologists
walked up.

It's been over thirty years ago and I scarcely remember the details, but
they quickly advised us that we already had a perfect administration route -
the endotracheal tube! We had never been instructed that we could administer
drugs through the tube. After checking to make sure they were who they
claimed to be, they assisted us by simply squirting meds in the tube and
resuming bag respiration.

The attempt was futile, but I still remember their help.

Rich S.

JJS jschneider@remove socks cebridge.net wrote:

"Ian Stirling" wrote in message ...
Totally different situations.

In one, you've got lungs full of stale air.
There is a reasonable amount of O2 in it, even after you pass out
(IIRC).

Hemeoglobin is very clever, but it's not magic.
It releases the molecule it's bound to (O2 or CO2) when it reaches somewhere
there isn't much of that gas.

Normally this is a good thing, but when the lungs are full of N2, not
only do you get the normal release of CO2, but the lungs now actively
strip oxygen from the blood, something which normally never happens.
snip
Ding! The light bulb is flickering. Thanks Ian, for being patient enough with me and taking the time to educate. I
was aware that hemoglobin exchanges CO2 and O2. I wasn't aware that it did so in the manner you describe releasing
either in a low presence of the gas in question. That is very interesting. I still do not understand why it took

Yup, it's a beautifully simple mechanism.

the victim so long to recover from a lack of oxygen unless there really was some brain damage that he recovered from
over time?? Do you have any links to the CO2/O2 exchange mechanism for further reading?

http://groups.google.co.uk/group/sci...ac2abacf99c7df

I _think_ this should work.
It's a thread on sci.space.tech, about vacuum breathing.

I can only assume that the long time to recover was due to slight brain
damage, due to the lack of oxygen.