Double-Sided - Double Head
- Dual Head (Combination) Stethoscopes - Consist of a
bell and a diaphragm. With the double sided stethoscope,
the user should open (or index) the bell or diaphragm
by rotating the chest piece. When the diaphragm is open,
the bell will be closed, preventing sound from coming
in through the bell and vice-versa.
Triple Sided - Triple Head Stethoscopes - Both the double
head and triple head stethoscopes have a diaphragm and
bell. The triple head also utilizes a corrugated diaphragm
for additional auscultatory capabilities.
Tunable Diaphragm Stethoscopes - A stethoscope equipped
with a tunable diaphragm allows the user to hear high
and low frequency sound without rotating the device.
Disposable Stethoscopes - Disposable stethoscopes allow
the user to throw them away after use. They prevent cross-contamination.
Stethoscope Response
Many factors contribute to acoustic response. Make sure
to check your stethoscope regularly. Normal wear and tear,
like keeping it in your pocket, may cause obstructions.
Stethoscopes rely on airtight seals o transmit sound.
Loose parts or cracked tubing can prevent this seal. The
proper headset alignment and the fit of the ear tips are
also major factors. There are also differences in hearing
from one individual to another, we at TheMedSupplyGuide.com
recommend trying different stethoscope models before purchasing.
Stethoscope Components
The Ear Pieces - There are three types of ear pieces.
There are the older threaded ear tips, snap-tight ear
tips, and newest soft-sealing ear tips. Proper fitted
ear tips are necessary to achieve optimal acoustic performance.
The Tubing - The two most popular tube designs are dual
tube design and the single lumen design. The dual tube
design consists of two internal tubes, each one going
to a separate ear. The single lumen design allows sound
to be carried to both ears through a single tube. It is
said sound quality is better carried in the dual tube
design.
The Bell - When indexed the bell allows the user to listen
to low frequency sound.
The Diaphragm - When indexed the diaphragm allows the
user to listen to high frequency sound.
The Chest Piece - The chest piece contributes to the sound
quality in a stethoscope. The weight and width of this
component will contribute to the sound intensity.
Long tube vs Short tube
Many stethoscope users have questions regarding the length
of the tubing. It has been said that a shorter tube will
provide for a better acoustic response. Instructors in
some medical programs recommend their students buy the
shortest tubing possible. Is this a myth? Consider this.
As tubing length increases, resonant frequency decreases
and lower frequency sounds increase. Heart sounds normally
are considered to have a lower frequency. So what's the
verdict? According to 3M, who did testing on there Littmann
series, found that "there is only a small difference
in sound between a short tube and long tube stethoscopes".
It is so small that the human ear can't tell the difference.
A longer tube may actually pickup low frequency sounds
better. Longer tubing will also give the individual more
freedom when working with patients and may relieve back
pain. So its a toss up. The manufacturer and style of
your stethoscope will ultimately determine the quality
of sound regardless of tube length.
Keep it Clean
In one study, 80% of 200 stethoscopes from four different
hospitals and clinics were found to be contaminated with
at least one microbe. Staphylococcus accounted for 83%
of the microbes cultured--and 58% of those organisms were
methicillin-resistant. The study also found that 90% of
the stethoscopes owned by physicians were contaminated.
Nurses' stethoscopes came in a close second. 79% of the
ones they owned were found to be contaminated. So disinfect
your stethoscope regularly. |
