About StethoscopesA stethoscope is defined as a medical instrument used for listening to the action of someone's heart or breathing. Modern stethoscopes typically have a small disk-shaped resonator that is placed against the chest and two tubes connected to earpieces. The word stethoscope comes from the Greek words stethos, meaning chest, and skopein, meaning to explore.
Rene Theophile Hyacinthe Laënnec (1781–1826) was a French physician who, in 1816, invented the stethoscope. Using this new instrument, he investigated the sounds made by the heart and lungs and determined that his diagnoses were supported by the observations made during autopsies. Laënnec later published the first seminal work on the use of listening to body sounds, De L’auscultation Mediate (On Mediate Auscultation). Laënnec is considered the father of clinical auscultation and wrote the first descriptions of bronchiectasis and cirrhosis and also classified pulmonary conditions such as pneumonia, bronchiectasis, pleurisy, emphysema, pneumothorax, phthisis and other lung diseases from the sounds he heard with his invention. Laënnec perfected the art of physical examination of the chest and introduced manyclinical terms still used today. |
The Idea |
The stethoscope is significant because it is one of the few devices used throughout one’s life and for all patients. It may be the one instrument common to all doctors. It is said that Dr. Rene Theophile Hyacinthe Laënnec, a 35-year-old French physician, received the foundation of the idea for his invention when he observed two children playing in a courtyard. Using a long piece of solid wood and a pin, they were sending signals to each other because one child received an amplified sound of the pin scratching the other end of the wood. He recalled this memory when monitoring a patient who claimed to have symptoms of a sick heart. Laënnec needed to place his ear on the patient’s chest, or immediate auscultation , to gain more information for a diagnosis. However, he was embarrassed to do so due to the age, sex, and weight of the patient. The story goes as follows: |
The Story |
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. I immediately saw that this might become an indispensable method for studying, not only the beating of the heart, but all movements able of producing sound in the chest cavity. Laënnec ultimately discovered that this method allowed for louder and clearer heart sounds. |