22" vs 27" stethoscope

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thechad

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Most cardio iii's I've seen come in 27 inches, but I have seen 22 inches as well. Is the shorter one better?

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bigger is better. always.

This is not true. Shorter stethoscopes, at least in my experience, give better sound. I don't know of any quantitative data, but it makes sense -- how perfect of a conduit do you think that rubber hose really is?

Granted, it means you have to get closer to patients, and that creeps out some providers...
 
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This is not true. Shorter stethoscopes, at least in my experience, give better sound. I don't know of any quantitative data, but it makes sense -- how perfect of a conduit do you think that rubber hose really is?

Granted, it means you have to get closer to patients, and that creeps out some providers...

Yeah but they wouldnt sell a 27" if it wasnt good enough. And honestly, even as a 150 lb guy (IE not huge), I put on a friends 22" and it looked like a toy around my neck.
 
Definitely go 27", trust me. You are gonna want that extra five inches when you have to listen to some fat disgusting slob's heart and your face is inches from his face because your stethoscope is only 22".
 
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I'm thinking about getting a horse stethoscope for the 500 pound sweaty unwashed non-tooth-brushing incontinent-of-stool homeless patients I have to examine
 
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This is not true. Shorter stethoscopes, at least in my experience, give better sound. I don't know of any quantitative data, but it makes sense -- how perfect of a conduit do you think that rubber hose really is?

Granted, it means you have to get closer to patients, and that creeps out some providers...

http://solutions.3m.com/wps/portal/3M/en_US/Littmann/stethoscope/education/stethoscope-anatomy/

Short vs. Long Tubing

Quite often health care workers raise questions regarding tubing length based on early publications claiming shorter tubing length provides better acoustic response. Some instructors have recommended their students buy the shortest tubing possible. In an attempt to clarify the information surrounding tubing length, Littmann stethoscopes has tested their product line to offer the following information about tubing length.

To explain our test results, it will be helpful to compare the tubing of the stethoscope to a garden hose. For example, an increase in the length of a garden hose will decrease the pressure at the end of the hose as a result of frictional and other internal forces. The same effect occurs when the tubing length of a stethoscope is increased. However, in the case of stethoscope tubing, change in length is relatively small; this decrease in acoustic pressure is not detectable by the human ear.

Additionally, as tubing length increases, resonant frequency decreases. Considering this fact, an increase in tubing length provides a better response to the lower frequency sounds (an advantage in auscultation). Many heart sounds fall below 150 Hz and are considered low frequency. Because it has been shown that the human ear is least sensitive to low frequency sounds, improved low frequency response is an advantage.

Taking these two factors into account, there is no detectable difference in acoustical performance between Littmann stethoscopes with shorter tubing vs. those with longer tubing. In fact, there may be some enhancements to low frequency sounds.

When purchasing a stethoscope, the health care practitioner needs to consider their own needs and practices. Longer tubing might be more appropriate for people wearing the stethoscope around their neck as it drapes better. The practitioner’s height and arm length should also be a factor to determine optimal tubing length. Many practitioners would like a little more distance from sicker patients while auscultating. Longer tubing also reduces the amount needed to bend over the supine patient which can stress the practitioner’s lower back.
 
Have an 18" Welch Allyn Elite (was a gift) and a 27" Litmann Cardio III (gift to myself). Comparable stethoscopes quality wise and hear absolutely no difference in sound quality. Still can't hear a II/VI murmur with either, still can hear a III/VI just fine. Can hear lung findings just fine with either. Moral of the story: It's more about the set of ears behind the tubes than the tubes themselves. No stethoscope can compare to experience.

But the difference where the extra length DOES help is what was noted in this thread. Shorter tube = closer to the patient. And no matter what your compassion/empathy/warm fuzzies clinical medicine class tries to convince you, closer is not better. I find it easier to focus on the auscultation findings when I'm not gagging on the stench of body odor.

My 2 cents.
 
Ew don't wear stethoscopes around your neck. Didn't you ever hear of the dude with the MRSA abscess on the back of his neck from his stethoscope? Put it in your pocket.
 
Get the longer one. I agree with everyone here. I have already treated many patients with whom the extra distance is greatly appreciated. Seriously, you would regret having to get that close no matter how touchy-feely you are.

And I also agree with pocketing your scope when not in use. Unless you are going to use it within the next 10 seconds, put it in your coat pocket or get yourself one of those hip clips for the scope if you are only wearing scrubs and no coat w/ pockets. This is not grey's anatomy or some other glorified medical soap opera. Keep it off your neck. The oils in your skin also degrade the rubber with time, especially the oils from your sweaty nape of the neck in the hot ICU.
 
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I have a 22" and I really want a 27"...not only b/c of what's been mentioned here, but just sheer logistics, when someone's in their normal clothes (like in outpatient clinic) or has a ton of tubes going everywhere, it can be pretty hard to reach my stethoscope to where it needs to be.

Also, in defense of folks who sometimes wear their stethoscopes around their necks, I don't always have room in my pockets!
 
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Most cardio iii's I've seen come in 27 inches, but I have seen 22 inches as well. Is the shorter one better?

Go with the 27 inch-- you want to be as far away from your patient as possible. If the sound is better, then you probably won't even notice it at this stage.
 
Ew don't wear stethoscopes around your neck. Didn't you ever hear of the dude with the MRSA abscess on the back of his neck from his stethoscope? Put it in your pocket.

True story, seen one.

I have also noticed that short tubing sounds better, but the smell is worse. I have a super-short Welch Allyn (14 inches or something, so none of you get to complain!), and 25 inch WA Elite.

The original research on stethoscope tubing length identified specific optimal lengths of 14, 18, and 24 inches (a previous post of mine was off by an inch).

I'm a fan Welch Allyn stethoscopes secondary to being an impartial opponent to the tunable diaphragm. The Welch Allyn also comes with the options of short and long tubing. Apparently all of you have the short one. The currently available Welch Allyn scopes are either 22 or 25 inches in length.

So, if you really can't decide between the 22 or 27 inch Littmann, do yourself a favor and get the 25 inch Welch Allyn.
 
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Go with the 27 inch-- you want to be as far away from your patient as possible. If the sound is better, then you probably won't even notice it at this stage.

Right. The 22 inch scope is undeniably better sound. Really no comparison. But once you've dealt with a few patients for whom hygiene is a dirty word, you'll be willing to sacrifice sound quality for distance. In the olden days they used to put their head directly on a patient's chest. No idea how they could stand that, but then again life expectancy wasn't that good back then.
 
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Right. The 22 inch scope is undeniably better sound. Really no comparison.

Is this from two different crappy steths? Littman says that there's no humanly detectable difference between the shorter and longer, and that longer might enhance low frequency sounds.
 
Is this from two different crappy steths? Littman says that there's no humanly detectable difference between the shorter and longer, and that longer might enhance low frequency sounds.

-
 
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I wouldnt go with data on the Littmann website that you can crosscheck elsewhere. Theres other data out there to support a detectable difference... including expert testimony. I was actually pimped on rounds about this stethoscope tubing length issue.

Another thing...
There was a paper published around July of this year which showed that, in vivo in order to get a low frequency response from a Littmann tunable diaphragm, one must press so lightly that coupling to the skin becomes the problem. Meaning, you need to press so lightly that your stethoscope isnt even on the skin, and you dont hear anything. So, if youre interested in low frequency sounds like diastolic murmurs, dont even get a Littmann.

So, you're working on finding those citations, right?
 
You do know that you can take the peds diaphragm off a littman III and make it a traditional bell right? (Thus eliminating the need for the tunable feature)
 
Have an 18" Welch Allyn Elite (was a gift) and a 27" Litmann Cardio III (gift to myself). Comparable stethoscopes quality wise and hear absolutely no difference in sound quality. Still can't hear a II/VI murmur with either, still can hear a III/VI just fine.
Really? a 3/6 is booming. I just learned from a cardiologist that it's a 3/6 if the murmur is as loud or louder than S2. If you can't hear any murmurs quieter than S2, you're not hearing much at all.
 
Get the longer one. I agree with everyone here. I have already treated many patients with whom the extra distance is greatly appreciated. Seriously, you would regret having to get that close no matter how touchy-feely you are.

And I also agree with pocketing your scope when not in use. Unless you are going to use it within the next 10 seconds, put it in your coat pocket or get yourself one of those hip clips for the scope if you are only wearing scrubs and no coat w/ pockets. This is not grey's anatomy or some other glorified medical soap opera. Keep it off your neck. The oils in your skin also degrade the rubber with time, especially the oils from your sweaty nape of the neck in the hot ICU.
Um, just wear it outside your collar. My scope is laying on my coat, on top of my dress shirt, on top of my undershirt. It's nowhere near my skin. I also use bleach wipes on it pretty often (1-2x a day). And I like the low blow jab that it's because we're trying to look like McDreamy.
 
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http://www.forusdocs.com/reviews/Acoustic_Stethoscope_Review.htm

So this article is one of your references. You don't mention one of the studies mentioned in the article:

http://www-ece.eng.uab.edu/DCallaha/Pubs/ScopeCallahan.pdf

Since this discussion started with tube length differences, I'll redirect it by quoting this more recent study:

"Previous studies have indicated that stethoscope qualities
such as tubing length and diameter, single versus
double channel, type of chest piece, and materials may
make a measurable difference in sound transmission.2,6
While this may be true, it is generally accepted that differences
due to tubing length and diameter are minor
enough that they are not detected by adults.
Chest piece
shape, angularity of the conducting channel, and especially
fi t of the ear pieces have greater bearing on the
sound transmission differences in stethoscopes.2,6"

Oh, and thanks for the cheap shot, calling me 'doctor'.
 
Oh, and thanks for the cheap shot, calling me 'doctor'.

Take what you want out of the articles. There are many articles, and clinicians who say that there are no differences among stethoscopes, and its what's between the earpieces that counts. Many articles also conclude that we can all stick with the Littmanns we already have because the negatives in accuracy are outweighed by price, ergonomics, sound intensity, etc. I figured that searching for ones that quantify some specific difference would be more useful than saying that none of this matters because we are going to get an echo anyway.

Im a medical student, says so on the left side of my post. You're a resident, says so on the left side of yours. I try and do what residents tell me, as much as I can. You asked if I was finding citations, and so I did. I call residents 'doctor'. I think they earned it.
 
Im a medical student, says so on the left side of my post. You're a resident, says so on the left side of yours. I try and do what residents tell me, as much as I can. You asked if I was finding citations, and so I did. I call residents 'doctor'. I think they earned it.

Well then, in that same spirit, I wish you the very best in the upcoming match.
 
Is this from two different crappy steths? Littman says that there's no humanly detectable difference between the shorter and longer, and that longer might enhance low frequency sounds.

Yet they sell both sizes...

It's basic physics that the shorter tube will have less sound deterioration. Whether it's humanly detectable depends a lot on a person's ears. I agree the difference is probably pretty minor, but not nonexistent.
 
Go with the 22", you'll get better sound. In vet med (where we can get bitten or stomped on by our patients), we don't even get 27".
 
Go with the 22", you'll get better sound. In vet med (where we can get bitten or stomped on by our patients), we don't even get 27".

fair 'nuff

27" sounds ridiculously long and unwieldy. My 22" has served me well thus far.

The Classic (not cardiology) littmann scopes are 28 inches long.... and the Littmann Anesthesiology scopes (which they dont make anymore) were 32 inches long or something.... you could hang yourself with them in the OR if you wanted.
 
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I find 22" to be a more comfortable length as far as lugging it around. Then again, I haven't had to use one as a medical student, just as an MA to do BPs (and HRs on infants and such), so the quality of the scope has mattered little. But having a 28" scope swinging from your neck is uncomfortable. I guess it could be stashed in a pocket, but then again a 22" would fit better . . .

I might change my tune on the wards . . .
 
I find 22" to be a more comfortable length as far as lugging it around. Then again, I haven't had to use one as a medical student, just as an MA to do BPs (and HRs on infants and such), so the quality of the scope has mattered little. But having a 28" scope swinging from your neck is uncomfortable. I guess it could be stashed in a pocket, but then again a 22" would fit better . . .

I might change my tune on the wards . . .

Funny, you've got a picture of the 25" Welch Allyn DLX as your avatar.
 
why the hell does everybody think im being sarcastic?

Funny because we wouldn't be having this argument between 22" and 27" if everyone could just agree on 25"

According to allheart.com, new ones come with 25" tubing now. I just got my tubing replaced about 2 weeks ago (25" for me, thanks).
 
why the hell does everybody think im being sarcastic?

Funny because we wouldn't be having this argument between 22" and 27" if everyone could just agree on 25"

According to allheart.com, new ones come with 25" tubing now. I just got my tubing replaced about 2 weeks ago (25" for me, thanks).


We're not used to sincerity here.

And it's exam time (for us at least) so increased stress.
 
The above mentioned review actually deducted points for stethoscopes with too short of a tube. It was part of their rating system.
http://www.forusdocs.com/reviews/Acoustic_Stethoscope_Review_page3.htm
Personally I consider a 27 inch length optimal. Definitely nothing less than 25 inch. Those few inches make a big difference. Allow me to elaborate, with some clinical vignettes

1. The Southeast Asian patient on the teaching service with unexplained hemoptysis, weight loss, shortness of breath, and cough. TB is on the differential. Initially the patient is in respiratory isolation until a biopsy is positive for nonsmall cell lung cancer. The masks come off and the medical students spend hours examing him. Six weeks after their discharge from the hospital, the routine culture comes back as multidrug resistant TB. The student with the short tube stethoscope is the only one who PPD converts.

2. The patient who has a tracheostomy which is colonized by MRSA and Pseudomonas. Each time he coughs a purulent green stream hits the face of anyone with a short tube stethoscope examining him.

3. The patient who smells like they havent bathed in the past year. You hold your breath while you examine them.

4. The lady with the pendulous breasts which totally obscure heart sounds. You lift her left breast to listen to her heart. Your stethoscope is shorter than her breasts. A personal touch in medicine is nice, but it shouldnt be quite that personal.

5. The guy with a history of diabetes and vascular problems, and you are listening to his femoral artery for bruits. He is attracted to you. The only saving grace is that his vascular problems have also rendered him impotent.

6. You hurt your back using a rowing machine at the gym before coming to work. You are having to bend low to check the blood pressure of a bedridden patient. You scream louder than the ob patients as your partially herniated disc herniates more completely.

7. The male infant on the peds service who isnt wearing a diaper. The thing they dont teach you in medical school is that a male infant will reflexly pee in your left nostril when you examine them. And their reach is longer than the 22 inch stethoscope you are using.

Need I say more?
 
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The above mentioned review actually deducted points for stethoscopes with too short of a tube. It was part of their rating system.
http://www.forusdocs.com/reviews/Acoustic_Stethoscope_Review_page3.htm
Personally I consider a 27 inch length optimal. Definitely nothing less than 25 inch. Those few inches make a big difference. Allow me to elaborate, with some clinical vignettes

1. The Southeast Asian patient on the teaching service with unexplained hemoptysis, weight loss, shortness of breath, and cough. TB is on the differential. Initially the patient is in respiratory isolation until a biopsy is positive for nonsmall cell lung cancer. The masks come off and the medical students spend hours examing him. Six weeks after their discharge from the hospital, the routine culture comes back as multidrug resistant TB. The student with the short tube stethoscope is the only one who PPD converts.

2. The patient who has a tracheostomy which is colonized by MRSA and Pseudomonas. Each time he coughs a purulent green stream hits the face of anyone with a short tube stethoscope examining him.

3. The patient who smells like they havent bathed in the past year. You hold your breath while you examine them.

4. The lady with the pendulous breasts which totally obscure heart sounds. You lift her left breast to listen to her heart. Your stethoscope is shorter than her breasts. A personal touch in medicine is nice, but it shouldnt be quite that personal.

5. The guy with a history of diabetes and vascular problems, and you are listening to his femoral artery for bruits. He is attracted to you. The only saving grace is that his vascular problems have also rendered him impotent.

6. You hurt your back using a rowing machine at the gym before coming to work. You are having to bend low to check the blood pressure of a bedridden patient. You scream louder than the ob patients as your partially herniated disc herniates more completely.

7. The male infant on the peds service who isnt wearing a diaper. The thing they dont teach you in medical school is that a male infant will reflexly pee in your left nostril when you examine them. And their reach is longer than the 22 inch stethoscope you are using.

Need I say more?

yikes!
That one somehow hit home...

My take-home point from this post is that there are plenty of ergonomic advantages to having a longer stethoscope, especially when examining pulmonary and peripheral vascular systems, rather than the heart.

thanks for that
 
Back to life...

Welch Allyn DLX and Elite stethoscopes come with the option of 28 inch tubing now. So, if you didn't like the Welch Allyn because of the shorter tubing... now its an inch longer than the Littmann Cardiology.

Standard (non-tunable) diaphragm and bell, and longer tubing... can't go wrong with the Welch Allyn.
 
27" sounds ridiculously long and unwieldy. My 22" has served me well thus far.

Depends on the person. I'm 6'5" and I can't honestly imagine having to use 22" or less for more than the time it takes to complete an OSCE. The 27" looks like a 22" on most people. :p Honestly, what little sound quality difference there is so trivial it is a matter of comfort. This is especially true for people like me who are still trying to figure out WHAT we are listening to rather than distinguishing between sounds.
 
It's not the size of the stethoscope that matters, its the location of auscultation baby :)
 
It's not the size of the stethoscope that matters, its the location of auscultation baby :)

Nah... many people say that girth is more important. :oops:

In terms of stethoscopes. The shorter 22 inch versions had additional girth (Welch Allyn and the older Littmanns). All the "technical advantages" were put on the uber-cardiology models.

I doubt that the 28" Welch Allyn has any difference in girth as compared to the 25"
 
Good grief! 22" girth?! That's the size of one of my thighs... crazy talk.

You should try finding jeans that fit right.

You have tiny friggin thighs by the way. My arms are about 19....(That isn't some lame attempt at bragging. I don't care about arms.)
 
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there was a rep @ our school recently selling the Cardio II for about $140. I know absolutely nothing about stethoscopes...but I've heard the Cardio II is the most popular at my school. Do you think those reps that come to the school are ripping us off? Have any of you ordered online and if so, what website did you use? What do you all think about the Cardio II?
 
there was a rep @ our school recently selling the Cardio II for about $140. I know absolutely nothing about stethoscopes...but I've heard the Cardio II is the most popular at my school. Do you think those reps that come to the school are ripping us off? Have any of you ordered online and if so, what website did you use? What do you all think about the Cardio II?


I think youre talking about the Cardio III. It should cost about $130, or less on Ebay. And its crap.

Get a Welch Allyn.
 
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