1. The first stethoscope was invented in 1816 by French doctor René Laënnec and consisted of a wooden tube, similar to an ear trumpet (used by those who were hard of hearing). The stethoscope was a monaural device, meaning it was used with just one ear. The picture below shows an example of this stethoscope.
2. Prior to the invention of the first stethoscope, physicians would place their ear directly to the patient (known as immediate auscultation) and percuss the chest (a process of gently tapping the body with fingers - still used today).
3. A series of updates and improvements were made in the mid 1850s including the development of the binaural device we know and continue to use today.
4. Dr David Littmann, a distinguished cardiologist and Harvard Medical School professor is accredited with further developing the stethoscope in the mid 1960s and in particular, improving the acoustic performance.
5. The basic components of the stethoscope are the headset, tubing, and the chestpiece (see image and additional information below).
6. Some stethoscopes feature a single head chestpiece that incorporates a diaphragm and bell into one - know as multi-frequency stethoscopes. These work by varying the pressure applied to the chestpiece to hear different levels of sound as if it was diaphragm/bell type (dual head).
7. The diaphragm is used to listen to high pitch sounds and the bell, mid and low pitch sounds.
8. The diaphragm of a stethoscope functions much like the human eardrum, in that it vibrates. These vibrations move the air in the stethoscope tubing, which in turn is detected by your eardrum and interpreted as sound by your brain.
9. The stethoscope can be used to listen to a variety of sounds to assist with the assessment and diagnosis of a patient. These include lung, heart and bowel sounds. The stethoscope is also routinely used in association with a sphygmomanometer to assess blood pressure by listening to blood flow sounds.
10. When using a stethoscope remember that the ear tips should point forwards in your ears to follow the natural path of your ear canals to ensure best acoustics. Best practice when using a stethoscope is to use it at skin level and don't forget to clean it after use to help control infection risk.
Stethoscopes are available in a complete range including disposable, paediatric, training, nursing, cardiology and electronic. We stock a range of stethoscopes suited to all budgets as well as replacement parts.
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The first ever stethoscope invented and used by French doctor René Laënnec in 1816.
René Laënnec, the stethoscope inventor, using immediate auscultation on a patient.
The basic components of a stethoscope.
Click on the image to zoom and find out more detail below.
Stethoscope ear tubes are connected by a tensioning spring that holds the earpieces firmly & comfortably in the ear. Some models have the ear tubes permanently affixed to the tubing. In less costly models they are a friction fit. Some stethoscopes have rotatable & adjustable ear tubes. The more expensive stethoscopes tend to have the ear tubes fixed at a 15 degree angle for a snug aural fit. Binaural can be machined from aluminium, brass (chrome plated) or stainless steel. Stainless is more durable and its general mass eliminates some of the extraneous noise.
Stethoscope ear tips are usually made of hard or soft plastic and are threaded, snap-on or friction fit. High quality stethoscopes generally have softer eartips that fit more snugly in the aural canal.
Stethoscopes have a rotating valve allows for a selection of one side of the chest piece or the other.
Stethoscope tubing is generally made of PVC and is used to transmit the sounds from the chest piece to the bi-aural (ear tube) assembly.
The diaphragm is used in the stethoscope for the detection of high frequency sounds. It is usually made of PVC or an epoxy fibreglass compound.
The bell side is used in the stethoscope or detection of low frequency sounds. Some stethoscopes have a single head and therefore the diaphragm and bell are combined, with the bell being activated by varying the pressure applied to the chest piece.
Diaphragm & and non-chill bell ring
Each stethoscope has a retaining ring that secures the diaphragm to the chest-piece. This may snap on or be threaded. Most stethoscopes feature a non-chill bell ring that insulates the metal bell to improve patient comfort. On higher quality stethoscopes, the ring also extends the walls of the bell to improving the acoustic performance.