You’d be forgiven for thinking that this instrument has been around since the dawn of time, because we’re all so used to having our chest ‘listened to’ as a very basic and routine part of most visits with the doctor, but in fact the first version was only developed around 200 years ago!
Derived from two Greek words – stethos (meaning chest) and scopos (meaning examination), the first stethoscope was invented in France by Dr Rene Theophile Laennec (1) in 1812. Prior to this, doctors would use direct contact methods such as ‘tapping’ onto the chest wall to compare the sound from one area to another or placing their ear right onto the patient’s chest. This was somewhat awkward to say the least but was also quite unreliable because it depended solely upon the doctor trying to position their ear in the right spot and being able discern every possible sound. Since they were not amplified, then important sounds could easily be missed!
Laennec was a gifted student who lost his mother at the age of 5 and so went to live with his great uncle who was a priest, before moving on to study with another uncle, who worked in the local university medical faculty. He was hooked on medicine from those early years, despite his father repeatedly trying to persuade him away from it!
Having endured the limitations described above during the examination of a young female patient, he had the bright idea to roll a sheet of paper into a hollow tube and used this to listen to the patient’s heart. He was astounded at the amplification of sound and hence set about designing what would be the very first stethoscope to be used routinely by all medical practitioners – a simple wooden tube. The device was monaural, so still had its limitations, but it was practical and reliable, and so changed the course of medical practise at that time.
It would be many years later when, in 1851 Dr Arthur Leared (from Ireland), took this design to the next level, creating the first bi-aural stethoscope (2), which was then further modified by George Cammann for commercial release in 1852. This became the basis of the modern-day version, although many additional improvements have since been made – most significantly those of Dr David Littmann in the early 1960’s. Under his guidance the stethoscope became more flexible, and more accurate in terms of its detection of sounds within the body (auscultation).
In 1967 Littmann partnered with 3M Healthcare(3) and the Littmann stethoscope became a dominant player in the market, even to this day. Whilst technology continues to improve the comfort, reliability and accuracy of the device, the basic principles have remained the same. Nowadays, the same technology is applied to acoustic; electronic; recording; foetal and doppler applications, with more to come!