The Stethoscope: Evolution of an iconic device

At a time when medical professionals and researchers are debating over replacing the stethoscope with smart devices, the 17th of february marked what would have been the 235th birthday of Rene Laennec (1781–1826), the inventor of the stethoscope.

In this tribute post, we describe the story of how this remarkable invention and its evolution came to be.

Throughout history, man has been constantly studying human physiology and its characteristics and since then, the crucial role that the heart plays in our bodies has been identified. Heart-“beats” can be pivotal signs when examining a patient. However, listening to these sounds has been refined over centuries. From physicians placing their ear directly on the patient to observe their internal sounds, to the birth of the stethoscope — the typical fixture around doctors’ necks and the symbol identifying them.

The practice of percussion and immediate auscultation were popular in physical examinations by the early 1800s. The French physician named Rene Laennec was a firm believer in this method of diagnosis. Yet, late in 1816, while examining an overweight woman suffering complications of the heart, Laennec realized that a simple device can aid physicians in avoiding the awkwardness of placing an ear to the chest of a patient and to better enhance the listening effectiveness in such cases. As the story tells, Laennec rolled up a bunch of papers and pressed it to his patient’s chest. The beating of her heart was suddenly audible and clear, and the stethoscope — an innovation that would fundamentally change the detection and diagnosis of lung and heart problems — was born.

After several trials, the instrument resembled a long, wooden tube. The effectiveness of this device lies in linking the sounds with specific physiological changes in the chest and the name stethoscope was based on the two Greek words, Stethos (Chest) and skopein (to explore). Using this invention, researchers continued investigating the importance of sound diagnostic medicine and the stethoscope continued to evolve.

The first stethoscope that allowed physicians to use both ears wasn’t made until 1851. However, bi-aural stethoscopes were met with some skepticism due to the belief of potential hearing imbalances that could result by using both ears instead of one. Therefore, the use of the monaural stethoscopes continued into the early of the 1900s. Later on, these concerns were diminished and the bi-aural stethoscope was a commonly used diagnostic instrument.

Today the stethoscopes we know are very similar to the ones used in the 1930s.

Many minor improvements were made to these iconic devices such as the use new materials like flexible rubber, stainless steel, tygon and flatter bells to make them lighter and easier to use.

Despite all of the improvements and changes, the stethoscope continues to serve the basic principle behind it; “to provide physicians with the means to perform auscultation and identify specific sounds within the body.”

Originally published at on February 19, 2016.