Stethoscope, the device used for listening to heart and chest sounds, bowel sounds and blood flow noises in arteries and veins, has been one of the most impressive inventions in the field for medicine. Prior to its invention, doctors would place their ears directly on the patient in order to listen to sounds, a method known as direct auscultation or use percussion(method of tapping on a surface to determine the underlying structure).
Auscultation became easier with the invention stethoscope. French physician, René Laennec is credited with the invention of the first stethoscope in 1816 at Necker-Enfants Malades Hospital in Paris. The idea of this invention came to Laennec when he was examining a lady who was overweight. He was reluctant to use direct auscultation on the female patient. Percussion was also of no use owing to the degree of fatness.
Laennec rolled a piece of paper to form a cylinder. With one end of the cylinder on the patient’s heart and other end to his ear, he was able to listen to the heart sounds. He was excited to hear the sounds very clearly. He went on to design the first stethoscope which consisted of a wooden tube and was monaural i.e it used one ear.
Irish physician Arthur Leared invented a binaural stethoscope in 1851 which used both ears. In 1852, George Cammann improved the design of the binaural stethoscope for commercial production.
The 20th century has seen many improvements made to the stethoscope including one which uses microphone to amplify sound.