The History of the Stethoscope

Two hundred years ago, a French doctor’s squeamishness about putting his ear to the chest of a plump young female patient to listen to her heart led to a revolution in our ancestors’ understanding of the human body. Dr. Rene Theophile Hyacinthe Laënnec (1781–1826) invented the stethoscope, today as iconic a symbol of the medical profession as the caduceus. As Dr. Ariel Roguin said in a 2006 history of the stethoscope for a medical journal, “The stethoscope may be the one instrument common to all doctors. … No other symbol so strongly identifies a doctor than a stethoscope dangling around the neck like a talisman.”

 

Prior to 1816, physicians relied on the naked ear to hear the sounds of the heart and lungs. The importance of breath sounds had been taught as early as the Ebers papyrus (circa 1500 BCE) and the Hindu Vedas (circa 1400–1200 BCE), and later by Hippocrates (circa 460–380 BCE), who suggested shaking a patient by the shoulders while listening to the chest to better detect fluid in the lungs. But this “immediate auscultation” was awkward for both doctor and patient and could easily miss key symptoms.

 

An improvement on simply putting an ear to the chest was introduced by Leopold Auenbrugger (1722–1809), a physician in Vienna who’d grown up in his family’s inn. Auenbrugger recalled how his father would test a wine cask’s fullness by tapping it; he theorized that a similar test could tell whether a human chest was filled with fluids. Though effective, his “percussion” technique failed to catch on until Jean-Nicolas Corvisart (1755–1821), physician to Napoleon, popularized it in 1808.

 

Lacking the stethoscope, however, physicians still had to get up close and personal with their often unbathed, lice-ridden patients.

 

Rene Laënnec had no shortage of incentive to advance medical diagnostic tools: His mother died of tuberculosis when he was 5 and he himself suffered from asthma. At age 12, he went to live with his great-uncle, Dr. Guillaume François Laënnec (1748–1822), dean of medicine at the university in Nantes. Young Rene began helping with patients at just 14 and became a third-class surgeon in a military hospital by age 18. But his uncle died—also of tuberculosis—and Rene’s career turned downward.

 

In 1816, Laënnec finally earned a position at the Necker Hospital in Paris. That was also the year, the story goes, when, while crossing the courtyard of the Louvre, he saw two children playing with a long piece of wood and a pin. One would scratch the end of the wood while the other listened at the far end.

 

Laënnec was later called to attend a young woman with “general symptoms of a diseased heart.” He was reluctant to place his ear on her chest because of her youth, gender and “great degree of fatness.” Then he recalled the children with the wood and pin.

 

He later wrote, “I recalled a well known acoustic phenomenon: If you place your ear against one end of a wood beam, the scratch of a pin at the other end is distinctly audible. It occurred to me that this physical property might serve a useful purpose in the case I was dealing with. I then tightly rolled a sheet of paper, one end of which I placed over the precordium (chest) and my ear to the other. I was surprised and elated to be able to hear the beating of her heart with far greater clearness than I ever had with direct application of my ear.”

 

Laënnec spent the next three years developing this idea, which he called simply Le Cylindre. After colleagues gave his cylinder various more colorful names, Laënnec allowed it to be called a stethoscope, from the Greek for “chest” and “to observe.”

 

Laënnec was as skilled a wood-turner as he was a physician, and replaced his paper cylinder with two connected pieces of hollowed-out wood. One end was placed in the doctor’s ear and the other, a funnel-shaped cone, against the chest. A further improved version, 12 inches long and 1.5 inches in diameter with a ⅜-inch central bore, was offered for 2 francs along with a copy of Laënnec’s treatise on “mediate (indirect) auscultation.”

 

That same year, Laënnec developed a fever, cough and shortness of breath—which he insisted was not tuberculosis.

 

As he sought to recuperate in his native Brittany, however, he asked his nephew to listen to his chest with a stethoscope and describe what he heard. According to Roguin, “The auscultatory findings were as alarming as they were familiar to this great chest physician who had heard the same sounds a thousand times before. By his own invention, he could no longer escape the ironic truth that he was dying from cavitating tuberculosis.” He died August 13, 1826, at age 45.

 

The simple wooden stethoscope Laënnec devised remained the state of the art for decades, with only minor changes. An 1828 improvement by Pierre Adolphe Piorry (1794–1879) was trumpet-shaped and added an ivory earpiece and chest piece, which sometimes were decorated in “medical scrimshaw.” A stethoscope made of gutta-percha, a natural latex from tree sap, was displayed at the Great Exhibition in London in 1851.

 

In 1852, New York City physician George Cammann (1804–1863) produced the “binaural” stethoscope, which had twin ivory earpieces connected by a hinge joint, tubes covered with wound silk and an elastic band. A hollow ball attached to the chest piece amplified sound. Physicians initially resisted the binaural design, thinking it might distort their readings, but eventually it supplanted Laënnec’s single-earpiece tube.

 

In the 1930s, flexible rubber and stainless steel made stethoscopes lighter and more flexible, and the “bell” at the end was flattened. Electronic amplification and noise filtration were added in the 1970s, along with an option for recording results.

 

But the principle of “mediated auscultation” inspired by Laënnec’s walk through the Louvre courtyard 200 years ago remains. That insight, according to medical historian Dr. Jacalyn Duffin, was a key step in the redefinition of disease from a collection of symptoms to a problem associated with an anatomical system.

 

1816 | Rene Laënnec invents the stethoscope
1819 | Laënnec publishes his original treatise on l’auscultation mediate
1828 | Pierre Adolphe Piorry develops a smaller, trumpet-shaped stethoscope
1832 | George Elliot includes a plug for the stethoscope (“the French instrument”) in her novel Middlemarch
1852 | George Camaann makes the binaural stethoscope
1890s | Rubber is first used in stethoscopes
1970s | Electronic amplification is added to stethoscopes
2015 | Daytime talk show hosts on The View learn that nurses do, in fact, use stethoscopes

 

 

• Oliver Wendell Holmes was inspired to pen “The Stethoscope Song” in 1848, about a stethoscope in which several flies become noisily trapped by a spider web.
• Fearful that their medical bags made them targets of thieves seeking opiates, doctors in the 19th century took to secretly carrying the drugs in hollow “medical canes.” One version incorporated a stethoscope in the body of the cane.
• Although Laënnec’s greatest contribution to medicine was the stethoscope, his name is also attached to cirrhosis, still sometimes referred to as “Laënnec’s cirrhosis” because of his study of the liver disease.