So... The first stethoscope is considered to be the “Aibolit tube” - a Pinnard type model, which was in the arms of doctors for quite a long time. The development of the chemical industry and the technology for manufacturing flexible rubber tubes have made it possible to create fundamentally new models of stethoscopes, but Pinard is still produced today - in the form of an obstetric stethoscope, because has sensitivity in a very limited range.

Stethoscope or phonendoscope?

The stethoscope is the first version of a device for listening to body sounds. To obtain sound, a sound-collecting funnel was used - a “bell”.

The phonendoscope appeared later (by the way, the term was proposed by the Russian scientist Nikolai Sergeevich Korotkov). In a phonendoscope, the sound-collecting funnel is covered with a membrane - a resonator, to enhance a certain frequency spectrum.

Often the device combines both a “bell” and a membrane - a resonator. It turns out to be a stethophonendoscope. In most stethophonendoscopes, switching between the funnel and the membrane is carried out using axial rotation of the head, but other systems are also found:

KaWe Planet- longitudinal rotation of the head

Dimeda- switching using a lever (model discontinued).

As a rule, high frequencies (heart sounds) are heard better with a funnel, and low frequencies (lung sounds) with a membrane. However, a lot depends on the manufacturer and the specific model of the stethoscope. For example, the 3M Littmann “Master” series has a dual-range membrane, which allows you to tune to high or low frequencies depending on the force of pressing the head.

Stethoscope tubes. Quantity and length.

As reported by German Riester engineers, the length of the tubes has virtually no effect on the frequency range and volume. But the number of tubes makes a difference! Two tubes connected directly to the head hear louder than one.
The traditional “two-pipe” system is considered to be Rappaport. Manufacturers often add the name (partial or full) of this type to the model name. A typical example is Riester Ri-rap:

Two tubes are connected directly to the head, resulting in louder sound than in single-pipe systems. However, there are also disadvantages:

• During auscultation, the tubes may rub against each other, resulting in acoustic artifacts in the form of crepitus, which must be learned to distinguish from true crepitus rales.
• Due to the additional tube, the system is quite bulky;

Both problems were solved in new stethoscope models.
The effect of crepitus was eliminated by releasing paired tubes - for example in the KaWe Planet stethoscope acoustic paths are soldered along the entire length, the tubes do not rub against each other.

Riester uses separate acoustic paths in the Cardiophon model, collected in one Y-tube.

As a result, the diameter of the common tube increased slightly, but overall this did not affect the compactness of the model.

Main components of a stethoscope:

1. Ear olives

There are several options:

• Hard (made of plastic, rarely used in modern stethoscopes, because they put painful pressure on the ear canal);
• Semi-rigid (material like thick PVC);
• Soft anatomical - made of soft PVC with thin walls.

The latter type is preferable - in addition to the fact that the anatomical soft olives do not put much pressure on the doctor’s external auditory canal, they improve sound insulation from external noise.

In “top” models of stethoscopes, the olives can rotate around their axis, which allows you to use the stethoscope with greater comfort - when moving the stethoscope up and down, the olives do not rub your ears and allow you to avoid acoustic artifacts arising from friction.

On the left in the photo is a new ergonomic Riester earpiece with the ability to rotate around its own axis.
On the right is a standard soft ear olive.

2. Metal arcs

Reputable manufacturers set the correct angle of the arches at the factory in the most comfortable position for the doctor. However, it is possible to adjust the rotation of the tubes, a kind of “fine tuning” to the individual characteristics of the user’s ear.

3. Spring. Happens:

• External. The most “budget” option;
• External folding. It is convenient because it adds compactness to the stethoscope, allowing you to store the device in a narrow pocket and the ability to quickly adjust the tilt of the arches;
• Internal hidden. Has a positive effect on ergonomics - does not cling to hair.

Some manufacturers (for example, Rudolf Riester) use a double hidden spring - this design allows you to correctly distribute the pressure on the ear canal and press the olives tightly but gently.

4. Acoustic tubes

Their quality determines how long your stethoscope will last you. Unfortunately, it is only possible to find out the quality of the material used during operation (especially if you purchased an inexpensive Asian device). In any case, it is worth considering that:

• Stethoscope tubes do not like strong heat and severe frost. Do not store the stethoscope on the dashboard of a car (they may fade) or in an unheated car interior in winter (cracks may appear).
• They do not like contact with oil and aggressive antiseptics such as chlorine. If necessary, wipe the tubes with 96.5% alcohol.

5. Membrane rings

• Regular plastic used in budget models from Asian manufacturers. They reduce the cost of the device, but cause discomfort to the patient;
• Uncooled. The so-called “warm plastic” does not cause an unpleasant reaction in the patient when the stethoscope head is applied to the skin;
• Metal. They have a positive effect on the overall “indestructibility” of the stethoscope, however, like any metal, they are cold. Before the examination, it is necessary to either warm the head of the stethoscope in the palm of your hand, or ask the patient to be patient.

6. Head.

The most common type is a stethophonendoscope: on one side there is a “bell”, on the other there is a membrane. The acoustic data of the stethoscope depend on the internal shape and design of the head, which manufacturers use their own know-how. Reputable manufacturers announce the characteristics in numbers or provide an acoustic graph:

And the smoother it is and the higher the number in db (decibels), the more noise you will hear and be able to differentiate without straining your hearing.

There is a membrane on the head of the phonendoscope. In addition to sensitivity, membranes are:

• flat,
• convex,
• convex in the center ("circles on water" type).

What type of membrane should I choose? There is no definite answer to this question; it all depends on the design features as a whole. In any case, the membrane must be sensitive in the range from 10 hertz to 1 kilohertz and made of high-quality materials.

Some interesting types of stethoscope heads:

Flat phonendoscopeAnestophon

Thanks to the “flounder” shape, the head can be easily slipped under the tonometer cuff. Or, while providing assistance, secure it with a strip of adhesive plaster on the patient’s body.

Stethoscope with a "floating" membrane

Rudolf Riester know-how - there are small grooves along the edges of the head, due to which the membrane does not have a rigid attachment, but “floats”, which made it possible to obtain high volume in almost all frequency ranges.

GildedKaWePlanet

One of the best stethoscopes known! In addition to excellent acoustic performance and the original steto/fonendo switching system, it has a gold-plated surface and an individual serial number. The model turned out to be so successful that the design has not changed for more than 25 years.

Dual band technology 3MLittmann

The Master series uses original dual-range membrane technology - sensitivity in different ranges depends on the degree of pressure on the head. However, as users of Littmann stethoscopes write, in order to listen correctly with such a stethoscope, some practice is required.

Three-in-one stethoscopeTristar

The set includes three quick-release heads that allow auscultation of patients from 0 to adults. More suitable for thoughtful “desk” work - in conditions of mass screening or emergency care, constantly changing heads is not convenient.

Stethoscope with replaceable membranes/bellsRi-Rap.

The set includes two membranes and three replaceable “bells”, three types of ear olives. This allows you to independently design a stethoscope according to your own preferences.

And at the end of the article, a small FAQ on stethoscopes

- What's the difference between a steel head and an aluminum alloy head?
- In terms of acoustics and ergonomics - as a rule, none. An aluminum stethoscope is lighter, while a chrome-plated steel one looks more solid.

- Is “latex-free technology” important?
- Most modern European manufacturers produce stethophonendoscopes using latex-free technology. An allergy to latex in the form of Quincke's edema upon skin contact is extremely rare; more often it manifests itself as a local reaction - redness of the skin of the palms, neck, and in patients - in places of auscultation. In general, the option is useful.

- What does a “cardiological” stethoscope mean?
- There are no global standards for “cardiological” stethoscopes. Manufacturers use this term when they want to focus the buyer's attention on improved frequency characteristics.

- How do stethoscopes for children differ from those for adults?
- Only the size of the funnel or membrane.

- Is it possible to listen to a child with an adult stethoscope, and an adult with a child’s stethoscope?
- It is possible for a child, although it is not very comfortable - it is difficult to localize wheezing. Using a children's stethoscope for research in adult patients is even more difficult - the head area is small, and accordingly, the depth of listening to the organs of an adult may be insufficient. Although, the determining factor is the skill and hearing acuity of the doctor.

And perhaps most important. A thoroughbred stethoscope will be a good help to a competent doctor. But it will never make a mediocre specialist an ace in diagnostics.

At the request of users of the MedCom website, we wrote an article about stethoscopes, types of devices, design features, answers to frequently asked questions.

So... The first stethoscope is considered to be the “Aibolit tube” - a Pinnard type model, which was in the arms of doctors for quite a long time. The development of the chemical industry and the technology for manufacturing flexible rubber tubes have made it possible to create fundamentally new models of stethoscopes, but Pinard is still produced today - in the form of an obstetric stethoscope, because has sensitivity in a very limited range.

Stethoscope or phonendoscope?

The stethoscope is the first version of a device for listening to body sounds. To obtain sound, a sound-collecting funnel was used - a “bell”.

The phonendoscope appeared later (by the way, the term was proposed by the Russian scientist Nikolai Sergeevich Korotkov). In a phonendoscope, the sound-collecting funnel is covered with a membrane - a resonator, to enhance a certain frequency spectrum.

Often the device combines both a “bell” and a membrane - a resonator. It turns out to be a stethophonendoscope. In most stethophonendoscopes, switching between the funnel and the membrane is carried out using axial rotation of the head, but other systems are also found:

KaWe Planet- longitudinal rotation of the head

Dimeda- switching using a lever (model discontinued).

As a rule, high frequencies (heart sounds) are heard better with a funnel, and low frequencies (lung sounds) with a membrane. However, a lot depends on the manufacturer and the specific model of the stethoscope. For example, the 3M Littmann “Master” series has a dual-range membrane, which allows you to tune to high or low frequencies depending on the force of pressing the head.

Stethoscope tubes. Quantity and length.

As reported by German Riester engineers, the length of the tubes has virtually no effect on the frequency range and volume. But the number of tubes makes a difference! Two tubes connected directly to the head hear louder than one.
The traditional “two-pipe” system is considered to be Rappaport. Manufacturers often add the name (partial or full) of this type to the model name. A typical example is Riester Ri-rap:

Two tubes are connected directly to the head, resulting in louder sound than in single-pipe systems. However, there are also disadvantages:

• During auscultation, the tubes may rub against each other, resulting in acoustic artifacts in the form of crepitus, which must be learned to distinguish from true crepitus rales.
• Due to the additional tube, the system is quite bulky;

Both problems were solved in new stethoscope models.
The effect of crepitus was eliminated by releasing paired tubes - for example in the KaWe Planet stethoscope acoustic paths are soldered along the entire length, the tubes do not rub against each other.

Riester uses separate acoustic paths in the Cardiophon model, collected in one Y-tube.

As a result, the diameter of the common tube increased slightly, but overall this did not affect the compactness of the model.

Main components of a stethoscope:

1. Ear olives

There are several options:

• Hard (made of plastic, rarely used in modern stethoscopes, because they put painful pressure on the ear canal);
• Semi-rigid (material like thick PVC);
• Soft anatomical - made of soft PVC with thin walls.

The latter type is preferable - in addition to the fact that the anatomical soft olives do not put much pressure on the doctor’s external auditory canal, they improve sound insulation from external noise.

In “top” models of stethoscopes, the olives can rotate around their axis, which allows you to use the stethoscope with greater comfort - when moving the stethoscope up and down, the olives do not rub your ears and allow you to avoid acoustic artifacts arising from friction.

On the left in the photo is a new ergonomic Riester earpiece with the ability to rotate around its own axis.
On the right is a standard soft ear olive.

2. Metal arcs

Reputable manufacturers set the correct angle of the arches at the factory in the most comfortable position for the doctor. However, it is possible to adjust the rotation of the tubes, a kind of “fine tuning” to the individual characteristics of the user’s ear.

3. Spring. Happens:

• External. The most “budget” option;
• External folding. It is convenient because it adds compactness to the stethoscope, allowing you to store the device in a narrow pocket and the ability to quickly adjust the tilt of the arches;
• Internal hidden. Has a positive effect on ergonomics - does not cling to hair.

Some manufacturers (for example, Rudolf Riester) use a double hidden spring - this design allows you to correctly distribute the pressure on the ear canal and press the olives tightly but gently.

4. Acoustic tubes

Their quality determines how long your stethoscope will last you. Unfortunately, it is only possible to find out the quality of the material used during operation (especially if you purchased an inexpensive Asian device). In any case, it is worth considering that:

• Stethoscope tubes do not like strong heat and severe frost. Do not store the stethoscope on the dashboard of a car (they may fade) or in an unheated car interior in winter (cracks may appear).
• They do not like contact with oil and aggressive antiseptics such as chlorine. If necessary, wipe the tubes with 96.5% alcohol.

5. Membrane rings

• Regular plastic used in budget models from Asian manufacturers. They reduce the cost of the device, but cause discomfort to the patient;
• Uncooled. The so-called “warm plastic” does not cause an unpleasant reaction in the patient when the stethoscope head is applied to the skin;
• Metal. They have a positive effect on the overall “indestructibility” of the stethoscope, however, like any metal, they are cold. Before the examination, it is necessary to either warm the head of the stethoscope in the palm of your hand, or ask the patient to be patient.

6. Head.

The most common type is a stethophonendoscope: on one side there is a “bell”, on the other there is a membrane. The acoustic data of the stethoscope depend on the internal shape and design of the head, which manufacturers use their own know-how. Reputable manufacturers announce the characteristics in numbers or provide an acoustic graph:

And the smoother it is and the higher the number in db (decibels), the more noise you will hear and be able to differentiate without straining your hearing.

There is a membrane on the head of the phonendoscope. In addition to sensitivity, membranes are:

• flat,
• convex,
• convex in the center ("circles on water" type).

What type of membrane should I choose? There is no definite answer to this question; it all depends on the design features as a whole. In any case, the membrane must be sensitive in the range from 10 hertz to 1 kilohertz and made of high-quality materials.

Some interesting types of stethoscope heads:

Flat phonendoscopeAnestophon

Thanks to the “flounder” shape, the head can be easily slipped under the tonometer cuff. Or, while providing assistance, secure it with a strip of adhesive plaster on the patient’s body.

Riester floating diaphragm stethoscopeCardiophon 2.0

Rudolf Riester know-how - there are small grooves along the edges of the head, due to which the membrane does not have a rigid attachment, but “floats”, which made it possible to obtain high volume in almost all frequency ranges.

GildedKaWePlanet

One of the best stethoscopes known! In addition to excellent acoustic performance and the original steto/fonendo switching system, it has a gold-plated surface and an individual serial number. The model turned out to be so successful that the design has not changed for more than 25 years.

Dual band technology 3MLittmann

The Master series uses original dual-range membrane technology - sensitivity in different ranges depends on the degree of pressure on the head. However, as users of Littmann stethoscopes write, in order to listen correctly with such a stethoscope, some practice is required.

Three-in-one stethoscopeTristar

The set includes three quick-release heads that allow auscultation of patients from 0 to adults. More suitable for thoughtful “desk” work - in conditions of mass screening or emergency care, constantly changing heads is not convenient.

Stethoscope with replaceable membranes/bellsRi-Rap.

The set includes two membranes and three replaceable “bells”, three types of ear olives. This allows you to independently design a stethoscope according to your own preferences.

And at the end of the article, a small FAQ on stethoscopes

- What's the difference between a steel head and an aluminum alloy head?
- In terms of acoustics and ergonomics - as a rule, none. An aluminum stethoscope is lighter, while a chrome-plated steel one looks more solid.

- Is “latex-free technology” important?
- Most modern European manufacturers produce stethophonendoscopes using latex-free technology. An allergy to latex in the form of Quincke's edema upon skin contact is extremely rare; more often it manifests itself as a local reaction - redness of the skin of the palms, neck, and in patients - in places of auscultation. In general, the option is useful.

- What does a “cardiological” stethoscope mean?
- There are no global standards for “cardiological” stethoscopes. Manufacturers use this term when they want to focus the buyer's attention on improved frequency characteristics.

- How do stethoscopes for children differ from those for adults?
- Only the size of the funnel or membrane.

- Is it possible to listen to a child with an adult stethoscope, and an adult with a child’s stethoscope?
- It is possible for a child, although it is not very comfortable - it is difficult to localize wheezing. Using a children's stethoscope for research in adult patients is even more difficult - the head area is small, and accordingly, the depth of listening to the organs of an adult may be insufficient. Although, the determining factor is the skill and hearing acuity of the doctor.

And perhaps most important. A thoroughbred stethoscope will be a good help to a competent doctor. But it will never make a mediocre specialist an ace in diagnostics.

Best regards, Alexander Stepanov
with the support of the German diagnostic equipment website de-diagnost.ru

Useful article? Share with your friends from social networks!

A stethoscope is an essential diagnostic tool that should be in any doctor's arsenal. Moreover, this is such a noticeable attribute that it is impossible to imagine a doctor without it. Ever since our university days, namely with the beginning of “Propaedeutics of Internal Diseases,” we have been asking the question: “Which stethoscope should I choose?” At the same time, due to inexperience or because time is running out, we take the first one we come across, without thinking about the nuances of the purchase.

In this article we will try to figure out what main characteristics you should pay attention to when choosing a stethoscope.

If you are interested in looking at the history of stethoscopes, you can do so by looking at

Device

Ear olives

Olives can be hard, semi-hard or soft. It is preferable to choose stethoscopes with soft olives because they do not cause pain and discomfort, and also do not create noise artifacts when listening to noises. The advantage of such olives is that they are more tightly fixed in the ear canal, which has a better effect on the differentiation of various noises.

Metal arcs

Necessary for placing olives, as well as for sound transmission. There are no significant differences between these tubes, except the material from which they are made. Tubes made from aluminum will be much lighter than others.

Spring holding the arches

The spring is necessary so that the arches with olives are tightly fixed in the ears of each individual person and do not fall out when the body position changes. It can be external, internal and folding. The internal one is convenient because hair does not cling to it, and the foldable one is convenient to carry in your pocket.

Acoustic tube

Made from various synthetic materials. When choosing, you need to pay attention to the thickness and length of the tube. The thicker the tube, the better the noise isolation, but the flexibility of the device decreases. The length of the tube varies from 30 to 50 cm, on average about 37-40 cm. It is better to take a longer tube so as not to stretch and bend over the patient, especially when auscultating lying patients. The number of tubes suitable for the head can be one or two - one from each ear. The last option is better because the sound is much louder. This system is called Rappaport.

Head

Usually the head consists of 2 rings: on one side there is a special membrane, on the other there is none, and the ring is much narrower. It is more correct to call such a device a stethoscope, but usually such a long name is not used, and they simply call it a stethoscope. Rings can be made from various materials: plastic or metal. Metal rings are made either from aluminum, which gives lightness, or from stainless steel, which makes the device heavier, but makes its application to the skin more airtight. Special attention should be paid to the membrane. The membrane must be made of high quality material and have high acoustic characteristics. Therefore, you should not expect high sound quality from cheap stethoscopes. The membrane can be flat or convex (sometimes convex in the center).

So, let's summarize what the best stethoscope should be:

1. Olives should be soft
2. The material of choice for metal arches is aluminum
3. Spring for arches is preferable internal or folding
4. Double thick acoustic tubes
5. Stainless steel diaphragm rings
6. Membrane made of expensive quality materials

What important qualities of a stethoscope would you highlight and recommend?

In the next article we will talk about popular companies producing phonendoscopes, prices and devices that have gone down in history

💡 And also on the topic:

• Pediatrician Igor Dolgopolov - About vitamins, vaccinations, standards and self-respect Today's publication is dedicated to Igor Stanislavovich Dolgopolov, a pediatrician working in Russia, who is a member of the Society of French Pediatric Oncologists and worries about the future...

• An excursion into the history of the stethoscope/phonendoscope

  Colleagues, I suggest you take a brief excursion into the history of the stethoscope/phonendoscope (based on materials from the Internet). Perhaps some of you will recognize old models that differ in appearance and design from

  18.09.2015

A diagnostic method that allows you to listen to noises made by the internal organs of the human body (called auscultation) involves performing a simple and informative medical procedure. It is used so often that the devices with which the procedure is performed have become symbols of the medical profession. This article will discuss the stethoscope and phonendoscope, the difference and distinctive features of these devices.

History of the creation of the stethoscope

The stethoscope was created by physician Rene Laennec in 1816. In order to listen to the heartbeat of a shy representative of the fair sex, who had an overly large bust, he had to apply folded sheets of paper to her chest. As a result, the doctor was able to not only make an accurate diagnosis of the patient, but also make sure that with the help of a simple piece of paper rolled into a tube and applied to the ear, sounds can be heard much more clearly.

After some time, Laennec managed to improve the device. Gradually, in practice, tubes made of wood or other suitable materials began to be used, having an expansion at the ends in the shape of a funnel.

Nowadays, a stethoscope is an instrument equipped with several modes for listening to sounds of different frequencies. It includes certain component parts: head, tubes and headphones.

In medicine, binaural stethoscopes equipped with two tubes are currently used. Wooden models are often used by gynecologists, who use them to listen to the fetal heart rate.

What is a phonendoscope

Many people are interested in what a stethoscope and phonendoscope are. The difference (the photo is proof of this fact) of these devices lies in the more advanced design of the phonendoscope.

These medical instruments are designed for the same purpose: diagnosing the functioning of the internal organs of the human body.

The phonendoscope, almost a hundred years after the invention of the stethoscope, was created by the Russian doctor Nikolai Sergeevich Korotkov.

A large number of people want to have information about how a stethoscope and phonendoscope work. The difference in the design of these devices is that a phonendoscope, unlike a stethoscope, has one more component - a membrane, which amplifies sound vibrations. It consists of a head, two tubes and a membrane.

Stethoscope and phonendoscope: difference, photo (how to distinguish devices)

In this article we will try to analyze the distinctive features of these medical diagnostic devices, which allow you to listen to internal organs for the noise they make.

A stethoscope and a phonendoscope (the difference is observed in capturing sounds and tones) are used for auscultation of different organs. The first makes it possible to clearly hear the tones of sounds and is used in the study of the heart and intestines.

A phonendoscope picks up high-frequency sounds better, but drowns out low tones. This device is most often used when performing auscultation of the respiratory organs and blood vessels. With its help, it is possible to listen to abnormal sound manifestations, despite the presence of other noise.

A stethoscope and a phonendoscope (the difference between these devices is that phonendoscopes, unlike their predecessors, are only of a binaural design) are instruments with the help of which effective procedures for diagnosing internal organs are carried out.

Rules for conducting auscultation

When carrying out this procedure, the main importance is compliance with certain conventions, and not the choice of a stethoscope or phonendoscope, which has its own characteristics. It is recommended to use one device, follow certain rules and adhere to auscultation techniques.

• This procedure is recommended to be carried out in complete silence in the room.
• The patient needs to take off his clothes.
• It is worth noting that the friction of the device against the hair on the patient’s body can cause an imitation of the noise that accompanies the work of the organ being examined.
• The tube of the stethoscope or phonendoscope should fit snugly (but without excessive pressure) to the patient's body.

The stethoscope and phonendoscope (the difference between their modifications and features is quite insignificant) have for a long time been one of the most popular diagnostic tools used in medicine.

Medical devices stethoscope and phonendoscope are designed to listen to noise in internal organs. Even though they perform the same function, there is a big difference between them. To understand what exactly the difference is, it is necessary to become more familiar with their structure and operation.

The differences between a stethoscope and a phonedoscope are the ability to capture high-frequency and low-frequency sounds, which is determined by the presence of a membrane

Before you find out what the difference is between a stethoscope and a phonendoscope, it’s worth understanding the features of using each of them.

A stethoscope is a medical device that allows a specialist to identify functional abnormalities in the functioning of internal organs and systems in a patient. It consists of such important elements as a head, a tube and headphones.

Several different models of stethoscopes have been developed, which differ from each other in purpose. The device is:

• Pediatric;
• Cardiological;
• Electronic;
• Obstetric.

Medical equipment is characterized by several modes that are needed to carry out a diagnostic procedure. To obtain the most reliable result during the study, you must adhere to the basic rules of working with a stethoscope:

1. Diagnostics, during which a stethoscope and phonendoscope are used, should be carried out in a closed room in which there is no unnecessary noise;
2. Listening is done only after the patient takes off his clothes;
3. If necessary, you need to switch the device to the required mode, which allows you to listen to sounds of different frequencies;
4. It is necessary to adhere to the required number of listening points.

Medical professionals do not have any difficulties when working with a stethoscope.

Obstetric stethoscope from the middle of the last century. Modern devices are indistinguishable from phonendoscopes, but the principle of the “bell” structure is the same

What is a phonendoscope

Another device that is designed to listen to noise is a phonendoscope. It allows you to assess the condition of internal organs and systems. The device copes well with identifying disturbances in the gastrointestinal tract.

A phonendoscope allows a specialist to assess the performance of large arteries and the heart. With its help, noises indicating acquired and congenital defects are heard. The phonendoscope also makes it possible to determine the degree of filling of the arteries with blood.

A phonendoscope is often used in the process of auscultation of the respiratory system. They listen to the chest area for the presence of wheezing, which may indicate the onset of an inflammatory process. The medical device allows doctors to diagnose respiratory diseases such as pneumonia and pleurisy.

Pediatricians use a phonendoscope when examining young patients. The device allows the doctor to determine the number of heartbeats and check the rhythm of the heart. The respiratory organs are also assessed.

Pediatricians use phonendoscopes

Differences between devices

Questions about the difference between a stethoscope and a phonendoscope have long been studied. A qualified specialist who regularly works with these devices can tell exactly what the difference is between them.

The differences between medical devices are that the phonendoscope membrane transmits high-frequency pulses through itself. The stethoscope tube, in turn, is designed to evaluate low-frequency impulses. The latter type of sounds can drown out high frequencies. That is why it makes sense to use this device for diagnosing lung and vascular diseases.

The phonendoscope membrane is capable of reducing the intensity of sounds of different frequencies, but at the same time it does not drown out high ones. So the device is appropriate to use when examining the condition of the heart and digestive organs.

The difference between the devices lies in their functional capabilities. The external characteristics of the devices are almost the same.

What is a stethophonendoscope

Stethophonendoscopes are often called simply stethoscopes.

In medicine, another device is used that makes it possible to listen to noise. When developing it, the functions of a stethoscope and a phonendoscope were taken into account, as well as those features that make them different. On their basis, a stethophonendoscope was created. The device combines the positive qualities of its two predecessors. It is not much different from them. Stethophonendoscopes are used to perform many operations that allow you to correctly diagnose the patient’s condition.

A modern noise drying device consists of 3 important components:

• Capsules that have a convex or flat membrane. She is responsible for receiving sound signals. The capsule is framed by rings made of metal or plastic. Metal structures are considered more durable, so they have a longer service life;
• Tubes through which sound vibrations pass. They can be rubber or vinyl. The latter are more preferable, since vinyl is able to isolate external noise more effectively;
• Olives for the doctor's ears. They come in rubber and plastic. The former are more comfortable, as they fit tightly in the ear canal.

Some models of the device are equipped with a spring. Its presence is reflected in the final cost of the medical device.

Modern devices have more extensive functionality than their predecessors. With their help, the doctor can listen to noise even in a noisy room, since these models are good at cutting out unnecessary sounds.