Stethoscope Parts | List, Names and Functions Explained

What are the parts of a stethoscope and their uses?

Stethoscope parts are basically like Oreo cookies. Yes, I know this doesn’t really make sense, but hear me out. You have the two chocolate cookies: The part the medical professional puts in his/her ears and the part that goes on the patient. The cream filling in the middle is, in this case, the tubing that connects the two.

While you might think it’s silly to think this hard about the parts of a stethoscope, knowing how to use one accurately can be very helpful in determining what the heck you’re actually hearing.

If all this did was confuse you more and just make you want Oreos, allow me to be a little more helpful.

What are the 3 main parts of a stethoscope?

I’ve seen various sources stating that there are three main parts of a stethoscope. Others claim there are five (or six, or seven, or eight). I have no idea where these numbers are coming from, but you guys know that I love to simplify things for you. So for this post, I’ll stick with the three major ones:

• The earpiece aka the nurse end
• The chestpiece aka the patient’s end
• The tubing aka the middle part that connects the two ends

If you’re not into Oreo cookies (first of all, how dare you…) then to put it simply, there are two ends of a stethoscope. One end of the stethoscope goes on you, and the other end goes on your patient.

What is the end of a stethoscope called? | The nurse side

Ear Tubes

Ear tubes of stethoscopes are hollow metal tubes (often made of aluminum or metal) that connect your earpiece to the tubing. Ear tubes are very important because they transfer sound from the patient’s body to the user’s ear canal. High-quality stethoscopes (or “bougie” stethoscopes, for lack of a better term) usually have better sound quality than the cheap-o isolation stethoscopes floating around most hospital units. Why? Because of the material used to make the ear tubes. Usually, the higher the quality, the sharper the sound. It’s always a good idea to consider stainless steel ear tubes!

Ear Tips

Ear tips go by many names. I’ve seen them referred to as ear tips, earpieces, and ear buds (just to name a few). The ear tips are small, soft pieces made of rubber or silicone material that go into the user’s ears. Ear tips are what allow healthcare providers to use stethoscopes without scratching the **** out of their ear canals, so it is nice to have soft, squishy ones (though definitely not necessary). It’s important to have a good form-fitting seal on your ear tips to avoid hearing confusing background noise, so don’t be afraid to explore the different sizes that ear tips come in.

Earbuds are also easy to wipe, remove, and replace. If you lose them or want to try a different size or style, they are usually very cheap as well!

What is the chest piece of a stethoscope called? | The patient side

When someone refers to the chest piece of a stethoscope, they are probably referring to the end of the stethoscope that houses the diaphragm or the bell. These two are arguably the most important parts of the stethoscope. If you take nothing else away from this blog post, please know this: It’s important to have an idea of what kind of sounds you can hear with the diaphragm vs. with the bell.

One quick note: The chest piece of a stethoscope can be one or two-sided. One-sided chest pieces only have a diaphragm and are usually the cheap disposable ones you’ll see on a hospital unit or in an isolation room. Two-sided chest pieces have both a diaphragm half and a bell half and would be seen on most commercial stethoscopes. It doesn’t always matter which one you use, but it does matter that you know what you’re listening for! Stethoscopes with two-sided chest pieces (aka ones that include both a bell and a diaphragm) are often referred to as dual-head design stethoscopes. I would highly recommend purchasing a dual-head design stethoscope and NOT a single-head design.

Diaphragm

The diaphragm is the large, flat, round end that goes on the patient’s chest.

Most nursing students (and nurses if we’re being honest) will end up using the diaphragm half of the chest piece far more than they will use the bell half of the chest piece. Diaphragms are more likely to be used on adult patients.

The diaphragm portion of a chest piece is used to hear HIGH frequency or high-pitched sounds produced by the patient. If you have no idea what that means, we’ll cover it in a minute, so keep reading.

Bell

The bell portion of the chest piece is the smaller of the two and is sometimes used less often than the diaphragm (depending on what kind of setting you’re in). It is used to hear LOW frequency or low-pitched sounds produced by the patient. You may see these used often in pediatric, NICU, or labor and delivery settings, as the bell is usually used on babies or small children.

What is the difference between a diaphragm and a bell?

Obviously, by now you know that the diaphragm is the big part of the chest piece and the bell is the smaller part of the chest piece. But why does it matter?

UpToDate has a great description of one key difference between the bell and the diaphragm

The bell is most effective at transmitting lower frequency sounds, while the diaphragm is most effective at transmitting higher frequency sounds.

Some stethoscopes combine these functions into a single surface. The intensity of pressure of the stethoscope against the skin determines whether the stethoscope functions as a bell or a diaphragm.

So what does this mean?

The difference between high-pitched and low-pitched sounds

You might use the diaphragm for high-frequency sounds such as

• Lung sounds
• Bowel sounds
• Heart sounds (if they’re normal)
• A normal adult head-to-toe

You might use the lower-frequency bell for

• Heart murmurs and bruits
• Some bowel noises
• Pediatric patients

What is the middle part of a stethoscope called?

The tubing is the part of the stethoscope that connects you to the patient. This soft, flexible line of tubing is what carries the sound from the patient to you. Without the stethoscope tubing, there would be no carrying of any sounds.

This is where some stethoscopes are labeled as dual-lumen tube design or single-lumen tube design. Dual-lumen tube designs have one channel for each ear, while single-lumen designs combine both channels in one tubing. It honestly doesn’t make a huge difference (in my own experience) which one you end up getting.

If you’re looking for a fun stethoscope color, it’s probably the tubing that you’re after.

And though stethoscope tubing inherently feels flimsy, a good stethoscope will have thicker, more durable tubing. Most tubing is made out of a material called polyvinylchloride, or PVC, which is a thicker material that essentially can be used and abused without breaking (and trust me, your stethoscope will probably take a beating at some point).

Just know it’s important to keep this part in good shape. If there are tears or cracks in your stethoscope tubing, you’ll probably want to invest in a better one.

I hope you found this rundown of parts of a stethoscope helpful! You can also check out a list of some things to consider before you buy a stethoscope HERE and HERE.

If you’re just getting started with nursing school, I know that a stethoscope feels like the least of your worries. You can read my top tips for success during your first year HERE as well as how to prepare for nursing school HERE.