By Paul K. Reilley, EMT-P, NASM-CPT, AAS and Steven L. Johnson, MHS-CL, BSN, NRP, CCP-C, CP-C, NCEE, CMTE
Your First (and Possibly Most Recent) Stethoscope Encounter
“Hand me your stethoscope and I’ll check breath sounds,” says your partner as you initiate care for your pediatric patient presenting with increased work of breathing. The time is 3:30 a.m. and you both, having been awake for only 15 minutes at this point, forgot the pediatric stethoscope from the “Peds Pack” in the ambulance.
You pause for a moment, hand over your stethoscope, and begin mixing a nebulizer treatment for what you assume will become a standard asthma workup. You ask your partner if they want you to grab the pediatric stethoscope from the ambulance and your partner replies, “No, I’ll just flip yours over to the child side, we’ll be fine.”
As you place a pediatric nebulizer mask on your patient, your sleep-deprived brain wonders why you hear Morgan Freeman’s voice narrating the scene… “But, they weren’t fine. In fact, they were far from fine. They didn’t have the right equipment for the job.”
What Did You Learn about Stethoscopes in Your EMS Classes?
If you were like most EMS students, you spent very little time learning about the stethoscope itself, instead focusing on reasons you might use a stethoscope, such as auscultating a blood pressure, assessing lung sounds, and you may have even learned how and where to auscultate heart tones (and you were likely told you cannot hear heart tones in the field anyway and not to spend time on it).
And, unless you purchased your own stethoscope, your only option might have been to train on a cheap, single-head stethoscope with rigid earpieces and a diaphragm with the same consistency as off-brand Tupperware.
Fast-forward to your first day in the field: you ask your preceptor why the department-provided stethoscope has a small end and why it has two tubes instead of one. Or maybe you assumed the small end was for small humans and proceeded to use it exclusively on pediatric patients. The answers you received almost certainly varied depending on who you asked, yet every time the response was said with such conviction, it must have been correct.
Maybe their recommendation to purchase a “really nice stethoscope” to improve your assessments is why you now drape your handy Littman Core around your neck at the beginning of every call. So, what is the truth? Do you really need a pediatric stethoscope, or are all stethoscopes created equal? Was the $400 well-spent?
Let’s further explore the world of stethoscopy and expand our knowledge of the most ubiquitous medical instrument in your arsenal. But first, let’s verify that we’re using it correctly.
Invention of the Stethoscope
The American Lung Association (ALA) attributes the creation of the stethoscope to a French physician named René Laennec in 1816. The (likely apocryphal) origin story claims Mrs. Laennec was upset about her husband placing his head on the chests of his female patients during medical assessments, so he rolled a paper tube and used it as a hearing funnel.
In reality, he probably just wanted to keep his distance from sick patients. Whatever the original cause, Dr. Laennec realized his simple invention actually improved his assessments by amplifying chest sounds.
He called this simple invention a “stethoscope,” from the Greek words stethos (chest) and skopein (to view or see). As a carver of wooden flutes, he combined his skills to create the first stethoscope, a wooden tube. This model would be used until 1851 when Irish physician Arthur Leared developed the binaural (with two earpieces) stethoscope.
Many physicians refused to use Leared’s binaural model for fear of inconsistency in what they would hear during auscultation. However, the model gained popularity, and in the 1960s, a Scottish physician by the name of Somerville Scott Allison designed his version of the stethoscope.
This new model used two “bells” to listen to different parts of the body at the same time, such as the heart and the lungs. Notice, Dr. Allison said nothing about combining the adult and pediatric stethoscope into one device. He did not say, “I have invented a device to listen to adult and pediatric patients with the same device.”
Here we dispel one of the biggest stethoscope myths—the bell of the stethoscope was not created to aid in the assessment of pediatric patients, but rather to auscultate heart and lung sounds of an adult at the same time, with the same device.
The Modern Stethoscope and Persistent Myths
Do you carry a Littmann stethoscope? Many EMS providers prefer it to other stethoscopes and pledge allegiance to all things Littmann. How did we get to this stethoscope from Dr. Allison’s two-bell device?
The ALA notes that the beloved Littmann stethoscope was developed in the early 1960s by Harvard Medical School professor and cardiologist, Dr. David Littmann. Littmann shared the device with the Journal of the American Medical Association (JAMA November 4, 1961), describing it as “an open chest piece for low-pitched sounds, a closed piece for higher-pitched sounds, firm tubing in the ‘shortest length possible,’ a spring to hold the earpieces together when not in use, and for the device to be lightweight.”
Again, a myth dispelled. The Littmann stethoscope, perhaps the most recognizable stethoscope brand in the medical industry, was designed to hear high- and low-pitched sounds with the same device. Not once did he mention the device to be a “one-stop shop and one size fits all and small.”
The Littmann brand has grown to include seven different stethoscope models, all serving different features and functionality. Of the seven, only two are designed specifically for infant and pediatric patients.
It is interesting to note that even the Littmann literature now states that their single-piece tunable diaphragms allow the provider to hear high- and low-frequency sounds with the same bell. This is the first place using a single stethoscope for adult and pediatric patient use is mentioned in using the modern stethoscope, yet many Littmann stethoscopes still have two bells.
The Right Tool?
If a single stethoscope is intended to be used for both adult and pediatric patients, why are we still using both adult and pediatric stethoscopes?
Please give Morgan Freeman a good listen the next time you grab your stethoscope and ask yourself: do I have the right tool for the job?
About the Authors
Paul K. Reilley is the EMS training captain for the Cy-Fair (TX) Fire Department. Steven L. Johnson is an associate instructor at Western Carolina University and a community risk coordinator at the Skyland (NC) Fire Department.
References
1. Laennec, René T.H. (1819). De l’Auscultation Médiate, ou Traité du Diagnostic des Maladies des Poumon et du Coeur [On Indirect Listening: A treatise on the diagnosis of lung and heart diseases]. Paris, FR: Brosson & Chaudé. 8. Two volumes.
2. Wong Lisa M.. (2014). Music and Medicine: Harnessing Discipline and Creativity. AMA Journal of Ethics, 16(8). https://doi.org/10.1001/virtualmentor.2014.16.8.mhst1-1408.
3. Nussbaumer, M., & Agarwal, A. (2022). Stethoscope acoustics. Journal of Sound and Vibration, 539, 117194. https://doi.org/10.1016/j.jsv.2022.117194
4. Rizvi, J. (2018, September 4). Listen Carefully, Inventor – The Medical and Dental Device Patenting Blog. www.medicaldevicepatentattorneys.com. https://www.medicaldevicepatentattorneys.com/2018/09/listen-carefully-inventor/
