Why do my lungs only resonate when I'm sick?
December 28, 2024 9:28 PM Subscribe
A few thoughts but that's mostly it.
I think most people are like me in this way: if you are asked to cough on a random Tuesday by your doctor, or if you happen to get some dust in your lungs, your cough will make a dry, noisy, mostly pitch-less sound. But if you're really sick with bronchitis or something else with a bad cough, you'll sometimes produce a deep howling tone from your lungs. You can feel your lungs/trachea resonating. Some people may call this a 'barking' cough.
I figure there's two main possibilities:
A) your sick lungs have sufficiently differently physical acoustics such that they resonate under forces where they would not if you were healthy.
B) your sick body unleashes forces that excite a resonant frequency whereas your healthy body does not.
Of course it could be a little of each. But ideally I'd like more detail as to why there's this sort of phase change.
Any thoughts? Relevant scientific sources especially appreciated!
Bonus semi-chat-filter: can anyone do this on command when they are not sick? Does anyone never make resonant tone when they cough?
I think most people are like me in this way: if you are asked to cough on a random Tuesday by your doctor, or if you happen to get some dust in your lungs, your cough will make a dry, noisy, mostly pitch-less sound. But if you're really sick with bronchitis or something else with a bad cough, you'll sometimes produce a deep howling tone from your lungs. You can feel your lungs/trachea resonating. Some people may call this a 'barking' cough.
I figure there's two main possibilities:
A) your sick lungs have sufficiently differently physical acoustics such that they resonate under forces where they would not if you were healthy.
B) your sick body unleashes forces that excite a resonant frequency whereas your healthy body does not.
Of course it could be a little of each. But ideally I'd like more detail as to why there's this sort of phase change.
Any thoughts? Relevant scientific sources especially appreciated!
Bonus semi-chat-filter: can anyone do this on command when they are not sick? Does anyone never make resonant tone when they cough?
tl,dr When part of your airway is narrowed by inflammation, rapid airflow through there is turbulent, which creates audible noise.
This noise, and also its acoustic filtering by the airway, varies depending on the location of the narrowing. Croup is narrowing around and below the glottis, its cough is "seal-like" with a honk-y resonant tone. Bronchiolitis is narrowing deep in the lungs, its cough (and breathing) has a high wheeze.
Bronchitis is anatomically in between those two, but I don't have a memory of its cough (probably because I haven't heard that one in a child struggling for breath).
(And yeah, if this happens more often than, I dunno, every couple of years, it might be worth checking out why.)
posted by away for regrooving at 10:14 PM on December 28, 2024 [7 favorites]
This noise, and also its acoustic filtering by the airway, varies depending on the location of the narrowing. Croup is narrowing around and below the glottis, its cough is "seal-like" with a honk-y resonant tone. Bronchiolitis is narrowing deep in the lungs, its cough (and breathing) has a high wheeze.
Bronchitis is anatomically in between those two, but I don't have a memory of its cough (probably because I haven't heard that one in a child struggling for breath).
(And yeah, if this happens more often than, I dunno, every couple of years, it might be worth checking out why.)
posted by away for regrooving at 10:14 PM on December 28, 2024 [7 favorites]
Bronchitis is the deep resonant one actually.
posted by I claim sanctuary at 11:19 PM on December 28, 2024 [1 favorite]
posted by I claim sanctuary at 11:19 PM on December 28, 2024 [1 favorite]
Response by poster: To clarify: the question isn't why do we always get a barking cough when sick (we don't). It's why do we only produce those coughs with clear pitches when sick (in certain conditions), and not in normal healthy conditions. The seal-like honk is a good example of the clear pitched tone I'm talking about. This isn't a question about my health and I don't need any further suggestion there. I'm fine thanks, I phrased the question in terms of my experience for simplicity but so far as I can tell my experience isn't notably different from any of my friends or family or presumably yours.
Restricted airways makes sense as part of what's going on but I look forward to additional input. Thanks!
posted by SaltySalticid at 5:53 AM on December 29, 2024
Restricted airways makes sense as part of what's going on but I look forward to additional input. Thanks!
posted by SaltySalticid at 5:53 AM on December 29, 2024
In 7th grade I got in a fight just before shop class started with a much bigger kid who was also a 7th grader (he was 5-6 inches taller than any teacher and broad in proportion).
He was turned away from me and I was teasing him (not about his height!) as part of a bid to make friends. But I said something that offended him (I never did figure out what), and he whipped around and took a big roundhouse swing at me, and somehow I found myself twisting his arm up behind his back. He’d taken a swing at me and I felt like I had to respond, but I wasn’t willing to hit him in the back of the neck or his kidneys, so I hit him in the ribs with the flat of my knuckles and it made a huge gonging sound that made everyone in the large space stop what they were doing and look.
I thought I was really in for it then, but he collapsed into a chair and spent most of the class period in bouts of periodic coughing. The gonging sound was very loud and almost musical, and I don’t think he had a cold or was asthmatic.
So perhaps normal lungs have resonant modes that require unusual circumstances to excite.
posted by jamjam at 8:11 AM on December 29, 2024 [1 favorite]
He was turned away from me and I was teasing him (not about his height!) as part of a bid to make friends. But I said something that offended him (I never did figure out what), and he whipped around and took a big roundhouse swing at me, and somehow I found myself twisting his arm up behind his back. He’d taken a swing at me and I felt like I had to respond, but I wasn’t willing to hit him in the back of the neck or his kidneys, so I hit him in the ribs with the flat of my knuckles and it made a huge gonging sound that made everyone in the large space stop what they were doing and look.
I thought I was really in for it then, but he collapsed into a chair and spent most of the class period in bouts of periodic coughing. The gonging sound was very loud and almost musical, and I don’t think he had a cold or was asthmatic.
So perhaps normal lungs have resonant modes that require unusual circumstances to excite.
posted by jamjam at 8:11 AM on December 29, 2024 [1 favorite]
Response by poster: Update for the record: my spouse thinks she could do it on command, but won't try bc she's afraid it would hurt. And she is mildly asthmatic.
posted by SaltySalticid at 9:42 AM on December 29, 2024
posted by SaltySalticid at 9:42 AM on December 29, 2024
Ah, as far as the pitched character of the sound: I would guess that the section of airway between the narrowing and your mouth is the resonator, being driven like a flute.
So, for reference, an open-ended one-foot tube has a fundamental wavelength of two feet, which is 500 Hz. Based on endotracheal tube measurements I see, the adult glottis-to-mouth distance is a bit shorter (20-25 cm) and children more so. That works pretty well to make the pitch of a croup bark.
Then the resonator formed by narrowing in the bronchi will be longer and lower-pitched, so that's directionally correct. I don't have a good estimate of either that length or the pitch of the cough to see if it lines up quantitatively.
posted by away for regrooving at 1:27 PM on December 29, 2024
So, for reference, an open-ended one-foot tube has a fundamental wavelength of two feet, which is 500 Hz. Based on endotracheal tube measurements I see, the adult glottis-to-mouth distance is a bit shorter (20-25 cm) and children more so. That works pretty well to make the pitch of a croup bark.
Then the resonator formed by narrowing in the bronchi will be longer and lower-pitched, so that's directionally correct. I don't have a good estimate of either that length or the pitch of the cough to see if it lines up quantitatively.
posted by away for regrooving at 1:27 PM on December 29, 2024
if you're really sick with bronchitis or something else with a bad cough, you'll sometimes produce a deep howling tone from your lungs. You can feel your lungs/trachea resonating.
I'd always assumed that this is down to some of the larger runs of tubing having become inflamed and swollen to an extent that under coughing pressure, parts of them get squashed together enough to start working like extra sets of vocal folds or perhaps even trumpet player lip buzz.
There are all kinds of ways to persuade somewhat compliant tubes to make noises, so I've always been kind of surprised that my lungs, which are essentially made of somewhat compliant tubes, work as quietly as they usually do.
posted by flabdablet at 6:42 AM on December 30, 2024
I'd always assumed that this is down to some of the larger runs of tubing having become inflamed and swollen to an extent that under coughing pressure, parts of them get squashed together enough to start working like extra sets of vocal folds or perhaps even trumpet player lip buzz.
There are all kinds of ways to persuade somewhat compliant tubes to make noises, so I've always been kind of surprised that my lungs, which are essentially made of somewhat compliant tubes, work as quietly as they usually do.
posted by flabdablet at 6:42 AM on December 30, 2024
You are not logged in, either login or create an account to post comments
But if this is happening I would guess there’s some underlying issue going on - I’m not sure everyone gets a barking cough when they get sick? If it were me, I’d want an x ray when sick and a pulmonary function test once things settled down.
Not to scare you, but I do know someone who coughs like that and he has a condition that’s one of the ones people want to avoid (COPD).
If pot smoking happens, an uncommon reason could be exposure to various pathogens (eg fungus).
posted by cotton dress sock at 9:46 PM on December 28, 2024