November 15, 2020

The stethoscope is an important tool for doctors, nurses, physician’s assistants, and other health care workers. A stethoscope is used to listen to internal parts of the body, such as the heart and lungs; this process of using a stethoscope to hear sounds normally imperceptible to the naked ear is known as auscultation.

Doctors rely on this tool to evaluate the functions of certain circulatory, respiratory, and gastrointestinal systems. Nurses also use stethoscopes to hear our pulse when measuring blood pressure. Stethoscopes amplify these sounds in our bodies to a level that healthcare professionals can clearly hear and use this important information when making diagnoses and caring for us.

Traditional stethoscopes work by transmitting sound from a diaphragm/bell chest-piece through an air-filled tube to the ear pieces. The diaphragm and bell are both designed to pick up the low frequency sounds generated by our body. The disc-shaped diaphragm picks up the relatively higher frequency sounds of breathing and the lungs, which fall in the 70 to 4,000 Hertz (Hz) range. The bowl-shaped bell on the other side of the chest-piece is designed to pick up lower frequency sounds in the 20 to 650 Hz range, such as the heartbeat.

Many medical professionals are among the nearly 40 million American adults who suffer from some form of hearing loss. With auscultation being such a routine and critical process for examining patients, what do medical professionals experiencing hearing loss do if they can no longer hear the sounds of their patients’ lungs or hearts? Fortunately, there are solutions.

What Products Exist to Help Medical Professionals Hear Better?

While several options exist to help hearing impaired medical professionals hear better during auscultation, the best option depends on several factors.

1. A medical professional who wears hearing aids may or may not want to remove their hearing aids during auscultation.

2. The style of hearing aid a medical professional uses will impact their options.

3. The features of the hearing aid the medical professional uses will affect the type of stethoscope they can use; for instance, a t-coil equipped or streaming enabled hearing aid.

The decision of how to handle auscultation will depend on the preferences of the medical professional and the hearing instrument that they use.

Amplified Stethoscopes Can Help

Medical professionals who are experiencing mild to moderate hearing loss and do not currently use a hearing aid may find great success just by using an amplified stethoscope. Amplified stethoscopes are designed for people who do not have significant hearing loss and only need a bit of a boost. They work in the same manner as acoustic stethoscopes, but the chest-piece includes a battery operated mechanism that the user can use to adjust to make readings louder or quieter. They also usually include a digital screen for taking readings. 

Like other personal sound amplification products, amplified stethoscopes increase the decibel level of sounds to make them more audible. The increase in amplification is usually in the range of 15 to 50 decibels. Some models even allow a pair headphones to be plugged into the device to make listening easier.

However, medical professionals experiencing moderate to severe hearing loss that do wear hearing aids may find that amplified stethoscopes alone do not provide enough amplification to hear lung and heart sounds. Amplified stethoscopes are also not programmed for any specific hearing loss, they merely amplify all sounds. Fortunately, there are amplified stethoscope solutions for hearing aid users.

Hearing Aids and Stethoscopes

There are many options for hearing impaired medical professionals that want or need to keep their hearing aids in during auscultation. The solution that works best will depend largely on the style of hearing aid. The main styles of hearing aids include completely in-the-canal (CIC), in-the-canal (ITC), in-the-ear (ITE), behind-the-ear (BTE) and receiver-in-canal (RIC) or receiver-in-the-ear (RITE).

For hearing aid styles that fit completely within the ear or ear canal, such as CIC, ITC, and ITE styles, the best solution may be to use special adaptors called stethomates. Steothmates are tips that replace the regular ear pieces on both acoustic and amplified stethoscopes which makes them compatible with the hearing aid.

For behind-the-ear styles of hearing aids, including RIC and RITE styles, that are equipped with induction loop technology (t-coil), an amplified stethoscope that has the same technology can be used to transmit the sound from the stethoscope directly to the hearing aids via the telecoils where they will be amplified by the hearing aid. If the BTE hearing aid is equipped for direct audio input (DAI), then it is possible to plug the amplified stethoscope directly into the hearing aid via a cable. A DAI boot or shoe may need to be installed on the hearing aid to make it compatible. Another method for BTE hearing aid users that have good low frequency hearing is to drill a vent hold in the hearing aid earmold such that either an acoustic or amplified stethoscope can be used as normal and the low frequency sounds will pass through the vent to the ear canal.

Another option that may work for some medical professionals that use any style of hearing aid is a stethoscope that is equipped with a headphone jack. The hearing aid user can purchase a pair of over-the-ear or on-ear headphones that simply plug into the amplified stethoscope. These types of headphones are usually large enough to accommodate most hearing aids, even BTE styles.

Other Things to Consider

If you choose to keep your hearing aids in your ears while performing auscultation, you may experience difficulty because your hearing aids are not programmed to pick up the very low frequencies associated with breathing and heartbeats. You might therefore consider having your audiologist provide a programmed setting that picks up these lower frequencies.

If you are a medical professional with a cochlear implant, there are options: several amplified stethoscopes can be connected to a cochlear implant processor directly via a patch cord. An alternative is to use an amplified stethoscope that gives a visual readout of the sound being picked up by the stethoscope.

The information in this guide has been written using the following reliable sources:

https://www.nidcd.nih.gov/health/statistics/quick-statistics-hearing

https://www.healthyhearing.com/help/hearing-aids/types

https://www.healthyhearing.com/report/46018-Stethoscope-hearing-aids

https://www.audiologyonline.com/articles/amplified-stethoscope-options-for-professionals-860

https://www.allheart.com/blog/sa/b-stethoscopes-hearing-aids/

https://hearinghealthmatters.org/waynesworld/2013/stethoscope-options-for-hearing-aid-users/