Here’s a question for those of us who like to discuss medical mysteries:
Human phisiology is sort of a hobby of mine, as a result anytime I see or hear of something that's amazing but true about the human body, I am compelled to determine a phisiological mechanism for such a thing. Today I am pondering the works of those down under digerie-doo(?) players. How on earth are they able to sustain circular breathing, shouldn't they burst?
I know for a fact that any time you inhale you are introducing a higher partial pressure gas mixture to a lower one in the alveoli. The result is a slight increase in the over all gas pressure in the alveoli itself. Fortunately when we leave enough time between inhalations the gas exchange that occurs allows for a decrease in pressure, oh, and of course we exhale.
When this process goes awry *BAM*, just like that, patient has a sycopal episode (passes out) and breathing returns to normal. Example:yper ventilation do to stress or anxiety. You freak out, inhale too much, alveolar pressure goes up, thorasic pressure goes up, tenth cranial nerve (responsible for regulating blood pressure) get's stuimulated, HR is reduced by brain, patient feels light headed, *BAM*.
SO...WTF is going on with these digerie-doo(!?) players. How can they continuously breath w/o passing out and what about maintaining the necessary volume when breathing IN the nose and OUT the mouth? Very trippy. Anybody who want's to take a crack at repiratory phisiology or pin it all on the supernatural powers in the outback fire away.
–J
P.S. What’s a WAG? I noticed someone say no WAGs please. Is this like WAG the dog? Is it an acronym. I gathered the meaning through it’s context (I hope). But I could use a line or two of confirmation.
This always fascinated me too. I mean, there’s only ONE airway into the lungs at one point, right? How can you breathe in and out thru it at the same time? It just don’t make no sense!
One more thing, how do you spell digerie-doo(!?!)?!? If you were going to post anyway, might as well save me the trip to the dictionary while I check out the rest of SDMB today.
You don’t actually breathe in and out at the same time. While exhaling, you let some extra air into your cheeks. Then you expel the air from your cheeks while breathing in through your nose. (This is how you do it with a trumpet. It’s probably about the same with a didgeridoo.)
Yes, with the added advantage that a digeridoo has quite a lot of reverb built into it, so it is more forgiving if you miss the odd millisecond here and there.
I’m going to see Rolf Harris live on stage next week.
Yep, my brass teacher tried to teach me how to do circular breathing and omphalo is correct, it’s a very difficult technique (also, as I was told never to let your cheeks fill up with air, one I failed to get right) which takes alot of skill.
B/F also told me that Kenny G uses this same technique - apparently he holds the world record for the longest sustained note on a wind instrument? Something like 27 minutes … ???
Note that the late Dizzy Gillespie used the cheeks-puffed-out variant of circular breathing, and he managed to do pretty well for himself. So stop beating yourself up, MC – I played trumpet & euphonium for many years, and never could figure out circular breathing (or multiple tonguing).
Kenny G may hold the Guinness Record, but if he does, I doubt it’s 27 minutes. Rahsaan Roland Kirk could allegedly play non-stop for two hours with this technique. He was also capable of playing three horns at one, and sometimes cobbled together his own instruments.
I’ve seen Kenny G do this on TV. It was edited down of course, who’d want to listen to one note for 45 minutes. Anyway he played that one note so long that his spit catcher thingy filled up and caused his instrument to stop playing.
Firstly I’d like to ask why you use the term partial pressure. It’s kind of true, but it’s also irrelevant and confusing. Let’s just stick to pressure OK?
Any time you inhale you are indeed introducing a higher partial pressure gas mixture to a lower one in the alveoli. What you are overlooking is the mechanism by which this is occurring .The reason there is a lower pressure in the alveoli is because the thoracic cavity has expanded. The lungs are literally taking up more volume, which creates a decrease in pressure. The result is in fact a slight decrease in the over all gas pressure in the alveoli itself. If, during inspiration, there were an increase in the over all gas pressure in the alveoli itself as you suggest then air would flow out of the lungs. This only happens during expiration, not inspiration.
There is no decrease in pressure caused by leaving enough time between inspirations. Firstly as I already pointed out the pressure in the alveoli is actually lower during inspiration, not higher. Secondly If you don’t leave enough time between breaths all that will happen is that the pressure will equalise as the thoracic cavity shrinks during expiration. No matter how rapidly you breathe the pressure in the lung must pass through stages of being both higher and lower than ambient air pressure jus for the process to work. You don’t need to wait. In fact waiting result in a longer period of unequal pressures, not lower.As the thoracic cavity expands ambient air pressure forces gas into the lungs, but this is going to be at best equal too and probably slower than decreasing lung volume to achieve the same effect on the way to expiration.
Again, it doesn’t work like that.
Hyperventilation doesn’t cause either thoracic or alveolar pressure to go up. As I already noted these pressures go through a cycle of being higher and lower than ambient pressure on every ventilation cycle. Twice during that cycle they will equal ambient pressure. This is no different to what occurs during normal ventilation.
During extended hyperventilation the patient feels light headed because the amount of CO2 in the blood has fallen de to excessive loss during respiration. This causes a rise in blood pH which causes the feeling of light headedness. It’s nothing at all to do with alveolar/thoracic pressure.
I used the Oxford Australian English dictionary to check that spelling. Interestingly enough they say that it is not an Aboriginal word but rather the British settlers’ version of what it sounds like. Doesn’t sound like that to me if I were going to represent that sound phonetically. Which I am not as I suck at that.
Macquarie gives both spellings and says it is probably imitative too.