March 01, 2007

Physiological Training (Episode 2)

Sorry it's taken so long to get the second installment out (btw - this will be a trilogy). But at least it hasn't been as long as we've waited for January Madness stories (if they exist).

After peaking at 35000 feet, we descended down to 25000. At this altitude it's still very cold. And a person's time of useful consciousness (TUC) is on average between 3 and 5 minutes. So I was understandably a little nervous when they instructed us to take off our oxygen masks. The idea was to be without O2 for long enough to experience and recognize our personal hypoxia symptoms. They also split us into two groups (one on each side of the chamber) so that we could objectively observe the symptoms of hypoxia in others.

They also gave us a worksheet which we were to do as hypoxia began its onset. I've scanned mine and posted it here. I find it quite hilarious. Quantum especially will enjoy noting that I only completed three of the five math problems. The fact that I couldn't do math (and got horribly lost in the worksheet maze) was probably my first clue that I was hypoxic. But I also experienced this crazy tingling all over my body - and not the good kind. So finally - after 5 and a half minutes without oxygen - I put my mask back on. I would point out that I was the last to do so in my group - but it wasn't a contest. But if it had been, I'd have won.

After recovering (which takes only about 20 seconds when breathing 100% oxygen), we got to sit back and watch the guys on the other side of the chamber do the same stunt. The guy across from me got so light urple and blue that he reminded me of Violet Beuregarde (from Willy Wonka). The guy next to him though was the only one of the lot of us who passed his TUC before putting his mask back on. Since he didn't pass out or die or anything, I think I'm allowed to say that it was kind of awesome. I had noticed he quit working on his sheet awhile ago. Then I saw his hand start to spasm. Soon his arm began to shake. At this point, the flight commander had noticed and - I might add - took the time to point out to all of us what was going on. By the time the commander put the man's mask on for him, the guy's whole upper body was rocking out. Twenty seconds later, he felt fine, but didn't remember a single thing.

After everyone had had a chance to recover, we began our descent to 18000 feet. At this altitude, the average TUC is probably 30 minutes. Once again they asked us to drop our oxygen masks. Further, they dimmed all the lights in the chamber and gave us a chart with some pictures and color wheels and whatnot. The goal here was to notice how our vision degraded over time as a low-grade hypoxia set on. All I can tell you is - a lot. At the end of the demonstration, we put our masks back on, and they brought the lights back up and I saw all sorts of colors and details on the chart that I had totally forgotten were there. My recommendation to you all, do not operate heavy machinery (or fly any form of aircraft - including fighter jets) while hypoxic.

On the startling conclusion of Physiological Training - rapid decompression and the definition of the term Gangload.


Hal said...

So . . . where's the worksheet?

Dr. Church said...

It's up now, primo.

Quantum said...

that worksheet is in fact damn hilarious

apologies for absent stories of the month which shall not be named. Next time I see you in person, I will presonally relay many of these tales, (for there are several)