Auscultation of the lungs

The auscultative method of research, like percussion, also makes it possible to evaluate the sound phenomena that arise in one or another organ and testify to the physical properties of these organs. But, unlike percussion, auscultation (listening) makes it possible to fix sounds that appear due to the natural functioning of the organ. These sounds are caught either by directly applying the ear to the subject's body (direct auscultation), or by using special trapping and conducting systems - a stethoscope and a phonendoscope (mediated auscultation).

Priority in the discovery of auscultation as one of the main methods of objective research, as already indicated, belongs to the famous French clinician R. Laennec, who apparently first used mediated auscultation, listening to the chest of the young patient not directly by the ear, but by folding into the tube sheet of paper, which was then transformed into a special device - a cylindrical tube with two funnel-like extensions at the ends (stethoscope). R. Laennec has thus succeeded in discovering a number of auscultative features that have become classic symptoms of the main diseases primarily of the lungs, primarily pulmonary tuberculosis. Currently, most doctors use auscultation mediated, although direct auscultation is also used, for example in pediatrics.

Auscultation is especially valuable in the study of the respiratory system and the cardiovascular system, since the structure of these organs creates conditions for the appearance of sound phenomena: the movement of air and blood is turbulent, but if along the course of this movement there is a narrowing (stenosis) of the bronchi and blood vessels, , then the swirling of the air and blood current becomes more pronounced, especially in post-stenotic areas, which amplifies the arising sounds, whose loudness is directly proportional to the current velocity and the degree c lumen clearance, the state of the environment (interstitial tissue, seals, cavities, the presence of fluid or gas, etc.).

In this case, the homogeneity or heterogeneity of the medium that conducts sounds is very important: the more diverse the surrounding tissue, the less its resonant properties, the worse sound phenomena reach the surface of the body.

These general physical regularities are especially clearly manifested in the lungs, in which very peculiar conditions are created for the occurrence of sound phenomena during the passage of air through the vocal cicle, trachea, large, middle and subsegmental bronchi, as well as its entry into the alveoli. Auscultation reveals these phenomena mainly on inspiration, but also the characteristic and exhalation is important, therefore the doctor necessarily estimates the inhalation and exhalation. The arising sound phenomena have received the name of respiratory noises. They are divided into respiratory noises, which constitute the concept of "type of breathing" and "additional noise".

There are two types of breathing, heard over the lungs, vesicular and bronchial.

Vesicular breathing

Vesicular breathing is normally heard almost over all parts of the chest, with the exception of the jugular fossa and the interscapular region (in asthenics) where bronchial breathing is noted. One should remember the most important rule: if bronchial breathing is found in any other part of the chest, it is always a pathological sign indicating the appearance of conditions unusual for a healthy person to better carry out respiratory noise formed in the region of the glottis and the beginning of the trachea (most often this is a homogeneous compaction of the pulmonary inflammatory tissues, for example infiltrate).

Although recently there has been an attempt to revise the mechanisms of formation of respiratory noise, but their classical understanding, proposed by Laennec, retains its significance. According to traditional views, vesicular breathing (the term Laennec) occurs at the time of air entry in the alveoli: the contact (friction) of air with the wall of the alveoli, its rapid expansion, the stretching of the elastic elastic walls of the set of alveoli during inspiration, create total sound vibrations that persist and at the very beginning of exhalation. The second important provision is that listening to this area of vesicular breathing or its variants (see below) always indicates that this lung area "breathes", the ventilating bronchi are passable and the air in this area is in contrast to the picture of "mute" »Of a mild - severe condition of spasm of small bronchi, clogging of their lumen with a viscous secret, for example, during the development of asthmatic status, when air does not enter the alveoli, the main respiratory noise is not heard and, as a rule, mechanical methods for restoring bronchial patency ( bronchoscopy with leaching and suction of thick secretions) to the resumption of vesicular breathing.

In addition to reducing the lumen of the bronchi, hypoventilation and recession of the lung (obturation atelectasis due to congestion by the growing endobronchial tumor, external compression of the lymphatic or tumor node, scar tissue), compression of the atelectasis of the lung (fluid or gas in the pleural cavity) leads to a weakening of vesicular breathing, a change in the structure of the alveolar wall - inflammation, fibrosing process, but more often loss of elastic properties with progressive pulmonary emphysema, as well as decreased lung mobility the standing of the diaphragm for obesity, the Pickwick syndrome, the emphysema of the lungs, the adhesive process in the pleural cavity, the pain sensations due to a trauma to the chest, fracture of the ribs, intercostal neuralgia, dry pleurisy ).

Among the changes in vesicular breathing, there is also an increase in it (above the areas close to lung tightening) and the appearance of hard breathing.

Unlike normal with severe vesicular breathing, the inhalation and exhalation are equally audible, while the sound phenomenon itself is coarser, contains additional noise effects associated with unevenly thickened ("rough") bronchial walls, approaching dry wheezing. Thus, in addition to the intensified (hard) inhalation, hard breathing is characterized by intensified (often elongated) hard exhalation, which is common in bronchitis.

Bronchial breathing

In addition to vesicular, normal in the lungs, another type of respiratory noise is defined: bronchial breathing, but the zone of its listening is limited, as indicated, only to the area of the jugular notch, the location of the trachea projection and the posterior interscapular region at the level of the VII cervical vertebra. It is to these areas that the larynx and the beginning of the trachea are contiguous - the place of the formation of gross fluctuations in the air flow that passes with great speed during inspiration and exhalation through a narrow vocal chasm, which causes equally loud sound on the inspiration and exhalation loud sound phenomena that are not carried out, however, on the greater part of the surface of the chest due to the heterogeneity of the medium created by the air pulmonary tissue.

R. Laennek describes bronchial breathing in this way: "... This is a sound that is breathed in and out by the ear in the larynx, trachea, large bronchial trunks located at the root of the lungs. This sound, audible when applying a stethoscope above the larynx or cervical trachea, is completely characteristic features. Breathing noise loses soft crackle, it's drier ... And you can clearly feel that the air passes into an empty and quite wide space. "

It should be emphasized once again that listening to bronchial respiration over any other part of the lung always indicates a pathological process.

The conditions for the best conduction of bronchial respiration on the periphery arise primarily in the compaction of lung tissue and the preservation of air passableness of ventilating bronchial tubes, primarily in cases of infiltration (pneumonia, tuberculosis, thromboembolic lung infarction ) and atelectasis (initial stages of obturation atelectasis, compression atelectasis), but also with the presence of the cavity (cavern, emptying abscess), the air of which communicates with the air column of the bronchus, trachea, larynx, and the cavity itself is surrounded by a denser lung oh cloth. The same conditions for carrying out bronchial breathing are created with large "dry" bronchiectasises. Sometimes above the superficial cavity, especially if its wall is smooth and tense, bronchial breathing acquires a peculiar metallic shade - the so-called amphoric respiration, sometimes heard even over the area of pneumothorax. In a malignant tumor, which is also a lung compaction, bronchial breathing, however, is often not heard, since the tumor usually clogs the vented condensed bronchi.

In addition to these two types of respiratory noise, a number of so-called additional respiratory noises can be heard over the lungs, which are always signs of the pathological state of the respiratory system. These include wheezing, crepitation, and pleural friction noise.

Each of these respiratory noises has a strictly defined place of origin, and therefore their diagnostic significance is very significant. So, rales are formed only in the respiratory tract (of different caliber of the bronchus), crepitation is an exclusively alveolar phenomenon. The noise of friction of the pleura reflects the involvement of pleural sheets in the process. Therefore, these noises are heard, preferably in the corresponding phases of breathing: wheezing - mainly at the beginning of the inspiration and at the end of exhalation, crepitus - only at the height of inspiration at the time of maximum opening of the alveoli, the pleural friction noise is almost the same during inspiration and exhalation all along their length . The sound characteristics of the respiratory sounds heard are extremely diverse, they are often compared to the sound of various musical instruments (flute, double bass, etc.), so the whole gamut of these sounds can be combined into a group that could be figuratively called a kind of "respiratory blues", since the timbre is really , specific overtones of adverse respiratory sounds may resemble the play of some musical instruments. Thus, the stridor arising from stenosis of the larynx or trachea in the case of edema of the mucous membranes, ingress of foreign bodies, the presence of a tumor, etc., is sometimes associated with muffled sounds of playing on a pipe "under the mute". Dry bass rales, formed as a result of the narrowing of the lumen of the large bronchi (tumor, accumulation of viscous sputum in the form of "drops" or "strings"), are similar to low sounds of bow instruments, for example, cello or double bass; at the same time, the sounds of the flute can serve as an acoustic analogue of dry treble rales that arise in the bronchi of small caliber and bronchioles due to spasm or obstruction.

Wet bubbling large rales, for example, with bronchiectasis, or small bubbles, for example, in bronchitis or pulmonary edema, are comparable to crackling of large or small gas bubbles bursting on the surface of the liquid. Short sounds of the "falling drop" in the case of fluid accumulation in cavities with dense walls (long-term tuberculous cavern, abscess of the lung) are analogous to abrupt hammer strokes on the xylophone keys. Crepitation, i.e. The characteristic crackling that occurs in the alveoli, partially filled with exudate in pneumonia, fibrosing alveolitis, etc., at the time of their "explosive" expansion at the inspiration height, is traditionally compared with the cracking of cellophane. And, finally, uniform repetitive movements of the brush on the skin surface can give an idea of the nature and mechanism of the formation of pleural friction noise in the fibrinous inflammation of the pleural sheets.

[1]

Chryps

Chrypses are respiratory noises, mainly arising in the trachea and bronchi, in the lumen of which there is content, but sometimes in the cavities communicating with the bronchus (cavern, abscess), with the rapid movement of air, whose speed is known to be greater when inhaled (inhalation - always active, exhalation - a passive process), especially at the beginning of it, so wheezing is better heard at the beginning of inspiration and at the end of exhalation.

In addition to the presence in the lumen of bronchi of more or less dense masses, which are driven by an air stream, the condition of not only the lumen, but also the walls of the bronchi (primarily the inflammatory process and spasm, which lead to a narrowing of the lumen of the respiratory tube) is important for the development of wheezing. This explains the frequency of rales in bronchitis and bronchial obstructive syndrome, as well as bronchial asthma and pneumonia.

R. Laennek described the phenomenon described by him as wheezing and detected by auscultation of the lungs: "... In the absence of a more specific term, I used this word, denoting as rattles all the noises produced during breathing by the passage of air through all those liquids that may be present in the bronchi or lung tissue. These noises also accompany coughing when it is, but it is always more convenient to examine them when breathing. " At present, the term "wheezing" is used only in the above situations, which always reflects the presence of pathological changes.

According to the nature of sound characteristics, wheeze is divided into dry and wet, among the humid are small-bubbly, medium-bubbly and large-bubbly, among the small-bubbly, ringing and unvoiced rales.

Dry rales are formed when air passes through the bronchi, in the lumen of which there is a dense content - thick viscous sputum, bronchi narrowed due to the swollen mucous membrane or due to bronchospasm. Dry wheezes can be high and low, have a whistling and buzzing character and are always audible all through the inhalation and exhalation. The height of the wheezing can be judged by the level and degree of constriction of the bronchi (bronchial obstruction): a higher timbre of sound (bronchi sibilantes) is characteristic for the obstruction of small bronchi, a lower (ronchi soncri) is noted for bronchial lesions of medium and large caliber, which is explained by different degrees obstacles to the rapidly flowing air. Dry wheezing usually reflects a generalized process in the bronchi (bronchitis, bronchial asthma ) and therefore they are listened to by both lungs; if dry rales are determined over a localized area of the lung, this is usually a sign of the cavity, especially of the cavity, especially if such a focus is in the apex of the lung.

Wet rales are formed when less dense masses (liquid sputum, blood, edematous fluid) accumulate in bronchi, when an air stream moving through them produces a sound effect, traditionally compared with the effect of bursting air bubbles passing through the tube through a vessel with water. Sound sensations depend on the caliber of the bronchi (the place of their formation). There are finely bubbly, medium- and large-bubbling rales. Most often, wet rales are formed in chronic bronchitis, at the stage of resolving an attack of bronchial asthma, while small bubbles and medium bubbling rales are inadvertent, as their sonority decreases when passing through a heterogeneous environment. Very important is the detection of sonorous wet wheezing, especially small bubbles, the presence of which always indicates that there is a peribronchial inflammatory process, and in these conditions, the compressed pulmonary tissue best conducts sounds in the bronchi on the periphery. This is especially important for identifying infiltration sites in the apex of the lungs (for example, tuberculosis) and in the lower parts of the lungs (for example, foci of pneumonia against the background of blood stagnation due to heart failure). Serious and large bubbling sonorous rales are less common and usually indicate the presence of partially filled with fluid cavities (cavern, abscess ) or large bronchiectasises communicating with the respiratory tract. Their asymmetric localization in the region of the apexes or lower lobes of the lungs is characteristic precisely for these pathological states, whereas in other cases these rales testify to the stagnation of blood in the lungs; when the lung is swollen, moist, large bubbling rales are audible at a distance.

[2]

Crepitus

Creption - a kind of sound phenomenon that occurs in the alveoli most often if they have a small amount of inflammatory exudate. Listened crepitations only at the height of inspiration and does not depend on the cough thrust, resembles crackling, which is usually compared with the sound that occurs when rubbing the hair near the auricle. First of all, crepitation is an important sign of the initial and final stage of pneumonia, when the alveoli are partially free, air can enter them and at the height of the inspiration cause them to splinter; in the midst of pneumonia, when the alveoli are completely filled with fibrinous exudates (the stage of curation), crepitation, like vesicular breathing, is naturally not listened to. Sometimes crepitation is difficult to distinguish from finely bubbly sonorous wheezing, which, as it was said, has a completely different mechanism. When differentiating these two sound phenomena, which testify to various pathological processes in the lungs, it should be borne in mind that wheezing is heard during inspiration and exhalation, crepitation - only at the height of inspiration.

With some changes in the alveoli not of a pneumonic nature with deep inspiration, a sound alveolar phenomenon, completely resembling crepitus, may occur, this occurs in the so-called fibrosing alveolitis, the phenomenon persists for a long time (for several weeks, months and years) and is accompanied by other signs of diffuse pulmonary fibrosis (restrictive respiratory failure).

It should be cautioned against the use of the still misunderstood "crepitating wheeze", in which the phenomena "crepitation" and "wheeze" are completely different in origin and place of origin.

[3], [4], [5]

Noise of friction of the pleura

Noise of friction of the pleura - gross fluctuations, heard (and sometimes palpable) when rubbing against each other changes in the inflammatory process of the leaves of the visceral and parietal pleura. In the overwhelming majority it is a sign of dry pleurisy as a stage 1 of exudative pleurisy, as well as subpleurally located pneumonic focus, lung infarction, lung tumor, and also pleural tumors. The noise of friction of the pleura is heard equally in inspiration and exhalation, in contrast to wheezing, moreover, it does not change when coughing, it is better performed when the stethoscope is pressed onto the chest and is maintained when the front abdominal wall (diaphragm) moves in a breath-holding condition.

If the inflammatory process captures the pleura near the pericardium, there is a so-called pleuropericardial noise. The conditional nature of the term is explained by the fact that noise is associated with the friction of altered pleura sheets caused by heart pulsation, rather than pericarditis.

Auscultation allows you to determine the ratio of time (duration) of inspiration and expiration, which, as already noted, is normally represented as follows: the breath is heard all over, exhalation - only at the very beginning. Any elongation of exhalation (exhalation is equal to inhalation, exhalation is longer than inhalation) is a pathological sign and usually indicates a difficulty in bronchial patency.

With the help of the auscultatory method, it is possible to approximately determine the time of forced exhalation. To do this, the stethoscope is applied to the trachea area, the patient takes a deep breath and then a sharp quick vschoch. Normally, the time of forced expiration is no more than 4 s, it increases (sometimes significantly) with all variants of bronchial obstructive syndrome (chronic bronchitis, emphysema, bronchial asthma). At present, the method of bronhophony popular with old doctors is rarely used - listening to whisper speech (the patient whispering words like "a cup of tea"), which is well captured by the stethoscope over the densified part of the lung, since the vibrations of the vocal cords in such a quiet voice, normally not transmitted on the periphery, are performed better through pneumonic or other tight focus, associated with the airway to the bronchus. Sometimes bronchophony can detect small and deeply located foci of compaction, when increased vocal tremor and bronchial breathing are not detected.

It is possible to recommend a number of methodical methods that allow in some cases to more accurately assess the revealed auscultative phenomena. So, for a more accurate definition of the area over which these or other pathological sounds are heard, it is advisable to move the stethoscope with each breath from the zone of the normal to the zone of altered breathing. If there are pronounced pleural pains that impede deep breathing, first one should assess voice tremor and bronchophonia, then over the area where these phenomena are changed, one or two deep breaths make it easier to establish one or another auscultatory sign (for example, bronchial breathing in the area of enhanced vocal tremor ). Using single breaths, one can better hear crepitation after a short cough, bypassing a series of painful ones due to deep breathing in the pleura process.

Auscultation after coughing makes it possible to distinguish rales from crepitations and pleural friction noise, as well as to exclude false attenuation or even absence of respiratory noises over the pulmonary segment due to bronchial secretion (after coughing, respiratory noises are performed well).

Thus, the diagnostic significance of each of the four main methods of studying the respiratory system can not be overemphasized, although special attention is paid to percussion and auscultation when identifying diseases of these organs .

With all the variety of data obtained using these methods, it is necessary to distinguish the following key points:

1. When examining the most important is the detection of asymmetry of the shape of the chest and the participation of its departments in the act of breathing.
2. When palpation, the asymmetry of the involvement of various sections of the chest in breathing is clarified, and also features of voice jitter (amplification and attenuation) are revealed.
3. Percussion first of all allows to detect various deviations of clear pulmonary sound, depending on the prevalence of air or dense elements in this zone.
4. At auscultation determine the type of respiration and its changes, evaluate additional respiratory noises (wheezing, crepitation, pleural friction noise) and the ratio of inspiration and expiration.

All this together with the results of additional examination allows you to diagnose one or another pulmonary syndrome, and then make a differential diagnosis, and therefore, to call a specific nosological form.