The stethoscope is a frequently used medical instrument. You may remember a time when a doctor pressed one against your back and chest to listen to the sounds made by organs like the heart and lungs during a routine physical. The disc-shaped resonator helps the physician hear high and low tones when connected to the hollow tubes and ear pieces. This is beneficial because it can help medical professionals discover underlying disorders more easily.
Invention & Early Years
Before stethoscopes became widely used, most doctors would simply place their ears to a patient’s chest to hear. Naturally, this accounted for some uncomfortable interactions, particularly between male physicians and female patients. Considering it was the beginning of the Victorian Era and such circumstances were more taboo, one French physician named Rene Laennec, devised an instrument in 1816 that would bypass the problem.
The first model was just a rolled piece of paper to listen to the echoes of the heart from a distance. From this original design, he was able to incorporate more parts that helped him hear more clearly than even pressing an ear against the chest.
For example, he took his original idea and developed an instrument crafted from a hollow wooden tube with a funnel that was placed into the physician’s ear for clearer auscultation. Still far from the models we have today, the resemblance became closer during the 1850s when Arthur Leared developed a dual eared model with metal parts, for even more accurate results.
By the early 1900s, latex was being used between the chest piece and the earpieces to make use easier, and only 50 years later latex tubing became the norm, making them even more flexible than before. During this period, Rappaport and Sprague developed a two-sided chest piece that helped physicians listen to both the heart and lungs. However, it was difficult to get clear sounds due to constant interference.
The late 20th century brought about much more developed prototypes. One of the most prominent physicians who helped improve the stethoscope was David Littmann, a British doctor who cemented the success of the two-sided chest piece. Now medical professionals could more precisely hear low and high-frequency sounds from the chest cavity.
Dr. Leslie A. Geddes, a physician and biomedical engineer, took it a step further by introducing the electronic stethoscope. This increased ease and reliability even further when diagnosing heart and lung conditions. It is now considered the gold standard in many medical practices.
Today’s stethoscopes come in many shapes and sizes, each with their own unique features used for a multitude of conditions. The most common application is still the assessment of cardiovascular and pulmonary functioning.
For small children, pediatric stethoscopes have been developed to fit their smaller frames, with more petite tubing and chest pieces. Veterinarians also can order animal-tailored models designed to pick up a wider range of frequencies to better treat more species of animals.
The newest models are much more sensitive and accurate than before. They allow doctors to detect even more subtle conditions like irregular heart rhythm and murmurs. After use, electrical stethoscopes can store patient data for later review, giving a better overall view of the patient's health.
Digital stethoscopes even have advancements like Bluetooth connectivity, advanced auscultation amplification, background noise cancelation, and tunable chest pieces for high-end precision.