Auscultation of the chest. Coursework: Animal Clinical Research

The study by tapping, with an assessment of the sounds arising from this, is called percussion.

Percussion as a method was proposed in 1761 by the Viennese physician L. Auenbrugger. For 47 years, Auenbrugger's discovery was considered of no practical importance. In 1808, Corvisart translated Auenbrugger's work into French and provided it with appropriate notes. After that, percussion became widespread. Further improvement and strengthening of the method is associated with the numerous works of a number of scientists and practitioners.

Of the authors who worked hard to improve percussion, one should name Piorri (1827), the inventor of the plessimeter (from the Greek Plesso - I strike and metron-measure) and Bury, who proposed a percussion hammer, further improved by Wintrich (1841).

In veterinary practice, percussion was applied in 1824 by Dupua from Alfort. Improved by I. Marek, who proposed a number of theories explaining the origin of percussion sound in normal and pathological conditions.

percussion technique. Distinguish between mediocre and direct percussion.

Direct percussion, proposed by the creator of this method, Auenbrugger, currently has only a minor application. It is performed with a bent index or middle finger of the hand, with which a short blow is applied to the underlying tissue. The sound in this case turns out to be very weak, and the determination of the properties of this sound presents considerable difficulties. In the study of the chest of animals, this method has been completely superseded by mediocre percussion. And only in the study of the frontal and maxillary sinuses, direct percussion is used with success to the present. Direct percussion can be used with palpation percussion, when it is necessary to obtain not only a sound representation of the organ under study, but also a tactile impression. Mediocre percussion can be of two types: digital and instrumental.

Digital percussion is performed by striking a finger on a finger. The index or middle finger of the right hand is used as a percussion hammer. The middle and index fingers of the left hand are tightly superimposed on the corresponding part of the body of the animal, at the same time, the remaining fingers are spread apart and do not touch the surface of the body. With a bent finger of the right hand, short blows are applied to the back of the plessimeter finger. The blow must be short and jerky and is made exclusively by the movement of the hand in the joint of the hand. The task of a finger-plesimeter, as well as a plesimeter, is reduced to a decrease in the propagation of sound over the surface and an increase in its propagation in depth. If during direct percussion, under the impact of a finger, an impression is formed in the soft parts and the energy of the percussion finger is partially lost, then with mediocre digital percussion, the hammer finger bounces off the plessimeter finger. All the energy when a finger strikes a finger goes deep and a louder percussion sound is obtained. Finally, the plessimeter protects the skin from pain during the examination.

The positive side of digital percussion is that the doctor is not dependent on the instrument and quickly accustoms his ear to the sound shades that are obtained during percussion. In long-haired animals, it is easier to push the hair apart with a plessimeter finger and to apply the finger more tightly to the skin of the animal. With digital percussion, the sound impression is combined with the tactile impression. The ability to determine underlying tissue resistance and low sound modification offer significant advantages over other methods. This should explain the fact that in medical practice, doctors percussion mainly with a finger on a finger. This method is also important when teaching beginners.

The disadvantages of digital percussion include relatively low sound intensity, soreness of the pessimeter finger during repeated examinations, and the inability to firmly apply the finger in some areas of the chest.

In veterinary practice, digital percussion can be successfully used in the study of small animals and young animals of large animals. As for adult horses and cattle, instrumental percussion is preferable when examining them. Digital percussion in large animals can be performed only in cases where there is no instrumentation at hand or when more precise localization of sound changes is necessary.

Instrumental percussion is performed using a percussion hammer and a plessimeter. Percussion with a finger on a plessimeter has not found wide application. The most common method is hammer percussion on a plessimeter.

As a plessimeter, plates of various shapes and sizes are used, made of metal, wood, bone and plastic. The shape of the plessimeter can be round, oval, quadrangular, in the form of a plate with curved ears and in the form of a goat's leg. Plessimeters with ears and in the form of a goat's foot are convenient in that they allow you to press them tightly against the surface of the body. The positive side of them is also the fact that they are portable and durable.

Percussion sound is highly dependent on the quality of the plessimeter. When choosing a plessimeter, it is necessary to be guided by the fact that it can be used for all animals. The most suitable are narrow plessimeters, in the form of a plate no more than 2 mm thick. The plessimeter must be firm and elastic. It should shrink a little and quickly return to its original shape. The energy loss of the percussion hammer in this case will be less. Plessimeters made of bone and hard rubber are recommended. Good sound is obtained when using wooden plessimeters. Plessimeters made of metal and glass, according to Marek, are less suitable, since they give a strong own sound. Less desirable gutta-percha plesimeters, as they are easily compressed, resulting in reduced sound penetration into the depths.

The percussion hammer for small and large animals differs in weight. If small hammers are used for percussion of small animals, then for large animals, medium or large weights are used. A mallet of medium weight, from 60 to 100 g, can be used for percussion of both medium and large, fat animals, and a mallet weighing from 200 to 400 g, although it is used for percussion of large and fat animals, has no particular advantages in terms of compared to medium weight hammers.

When choosing a percussion hammer, the elastic band is essential. The purpose of this rubber pad is to dampen the instrument's own sound. It should be taken into account that hard elastic bands give an almost metallic sound, which, joining the sound of tissues, greatly changes it, thereby making it difficult to assess. A rubber band that is too soft weakens the impact and creates popping noises. The best is considered to be an elastic band of medium elasticity with a rounded end. This rubber gives better sound quality. The handle of the hammer can be metal or wooden and should only meet the requirements for the convenience of fixing it in the hand.

Instrumental percussion is good in that it causes more significant and deep-reaching tremors of the percussed parts, and therefore is especially suitable for examining large and fat animals. This percussion is performed as follows: the pessimeter is pressed tightly against the part of the body to be examined with the left hand. With a percussion hammer, clamped in the right hand, short jerky blows are applied. The handle of the hammer should be slightly movable, and the movements of the hand are made only with the hand. Only in this case is it possible for the hammer to bounce off the plessimeter.

The force of impact with a percussion hammer must be changed depending on the thickness of the chest and the goals of percussion. The percussion of well-fed animals requires a stronger impact and gives better effect when using metal pessimeters; on the contrary, percussion of the chest of poorly fed animals is performed with less force and using bone or wooden plessimeters. The impact force also changes in cases where the foci are located at unequal depths. When detecting superficially located foci, weak percussion is used, and deep-lying lesions are recognized only when strong percussion is used. Obtaining a clean, unmodified sound requires a snug fit of the plessimeter to the skin of the animal. With incomplete contact, a significant layer of air between the plessimeter and the surface of the body changes the percussion sound, giving it a tympanic shade.

During percussion, the ear should be at the same level with the plessimeter. To do this, you have to give the necessary position to your body. It is best to percuss the chest on a standing animal, and only in forced cases, percussion is performed on an animal in a supine position. Impacts with a percussion hammer or finger should be applied perpendicular to the plane of the plessimeter. With an oblique hammer blow, a tympanic shade of percussion sound is obtained.

The most successful percussion is obtained in a small, closed room, if the animal is in the middle of this room. The sound in this case is clearer and cleaner, as it is amplified due to the air column and the reflections of sound waves from the walls of the room; in the open air there is neither resonance nor reflection of sound waves and, in addition, extraneous rustles and noises interfere. Percussion carried out in the open air often requires checking it indoors.

Distinguish between stokkato and legato percussion. Stokkato percussion is produced by jerky, short hammer blows, which instantly bounce off the surface of the plessimeter. This type is used to detect pathological changes in organs. Legato percussion, on the other hand, requires lazy movements, with a delay of the percussion hammer on the plessimeter. It is used for topographic research.

Percussion of light force provides a more accurate delineation of organs and an easier establishment of their boundaries. With delimiting-topographic percussion, the blow should be short, light, and the impact surface should be small. For this purpose, in medical practice, Plesh percussion is used, which consists in the fact that the finger-plessimeter is bent at the first interphalangeal joint at a right angle and the fingertip is applied to the surface. With this position of the plessimeter finger, the percussion area is significantly reduced.

Goldscheider suggests percussing the bent finger with a glass rod and so weakly that the sound is picked up only in places where there is tissue containing air under the plessimeter finger. This method is called percussion at the threshold of sound perception.

The best percussion method should meet the following requirements.

1. Prevent the spread of vibrations on the surface of the chest.

2. Facilitate access to the examined organ of the plessimeter and the hammer, reducing the thickness of the chest or abdominal wall.

3. Identify only the organ that is of interest at the moment.

The first condition can be fulfilled by the use of weak percussion in a limited place; the second is carried out by pulling the skin with subcutaneous tissue to the side and the third by delimiting the organ of interest from neighboring organs. With comparative percussion, it is necessary to choose symmetrical places on the chest and compare rib with rib, intercostal space with intercostal space and try to percussion in the same phases of breathing.

Percussion, like any other research method, requires constant practice and a certain amount of experience. It is necessary to carefully observe the conditions and basic rules of percussion. For a correct understanding of the various variations in the change in sound during percussion, one should not only master the technique of percussion, but also study various animals, taking into account the age and structure of the chest, as well as study the percussion sounds obtained from a healthy and sick animal.

Percussion theory. Percussion in the physical sense is a push that causes vibrations in the material environment. The resulting sound waves pass through a number of media, are transformed depending on the degree of elasticity of the latter, and are captured by our ear as sound (ear-receiver).

Experiments have shown that even with strong percussion, the area of ​​sound propagation over the surface does not exceed 2.5 cm, and in depth up to 7 cm. cm into the thickness of the lung, i.e., it allows you to detect changes only in areas located superficially. In large animals, foci located deep in the lung cannot be detected by percussion.

According to the Skoda classification, the qualitative differences in sounds obtained by percussion of various organs and tissues are divided into the following main types.

Clear or loud Dumb (dull) or quiet

Full or long Blank or short

High Low

tympanic

non-tympanic

These basic types of percussion sound can be combined; tympanic sound can be high and low, loud at the same time can be hollow and long, and quiet can be short and empty, etc.

Qualitative varieties of sound depend mainly on the airiness of the organ. Bodies devoid of air, when percussed, give a very short and quiet sound, which is called empty or dull. When percussion of organs containing air, the sound is long and loud. The degree of clarity of sound in this case depends not only on the airiness of the organ, but also on the strength of the percussion, the tension of the walls and the thickness of the chest or abdominal wall. A clear sound can be tympanic and non-tympanic (atympanic). It depends on the number of vibrations that form the sound. The difference is created by our own ear. The ear is not able to catch the pitch of the atympanic sound, to determine its low sound, while in the tympanic sound the pitch and its tone character are clearly distinguished.

By the properties of the emerging sounds, this method makes it possible to judge the physical state of the organs under study, i.e., the greater or lesser content of air in them. As for the conclusion about the anatomical and pathological changes that are made on the basis of percussion, not only percussion data are taken into account and compared, but also information obtained by other methods.

Percussion is the most difficult physical method of examination, requiring the most training. This is due to the fact that the researcher himself has to extract sounds, listen and evaluate them, be both active and passive and objectively evaluate what you hear.

The purpose of the lesson. To master the general methods of studying animals: examination, palpation, percussion, auscultation; master the technique of thermometry; familiarize yourself with special research methods.

Research objects and equipment. Horses, cows, dogs.

Percussion hammers, plessimeters, phonendoscopes, stethoscopes, sheets or towels for auscultation, thermometers.

Common methods of clinical examination include inspection, palpation, percussion, auscultation, and thermometry. Mastering these research methods is one of the main conditions that allow a specialist to identify pathology. In most cases, to clarify the diagnosis, along with general methods, it is additionally necessary to apply special research methods: instrumental and laboratory methods.

Inspection (from lat. inspection- examination, verification). This is the simplest and most affordable method of studying an animal. Inspection is preferably carried out in natural light (daylight) or in good artificial light. Inspection can be performed with the naked eye or with the use of special instruments. The animal is first subjected to a general and then a local examination. General inspection. It involves an examination of the entire body of the animal, regardless of the possible localization of the disease process. At the same time, it is possible to draw conclusions about the position of the body in space, fatness, physique, the condition of the skin and hair, superficial lesions, discharge from natural openings, the condition of the eyes, to identify excitation, depression or other signs characteristic of dysfunctions of organs and systems of the body.

Local inspection. This is an examination of the injuries or parts of the body found during a general examination of the animal, where the disease process is mainly localized.

Local examination can be divided into external, when the outer integuments of the animal’s body are examined, and internal, when areas located not on the surface of the body, but in depth, such as the cavity of the larynx, pharynx, etc., are subject to examination.

In the study, various instruments can be used, including those equipped with light sources. With the use of instruments, the following can be examined: oral and nasal cavities, pharynx, larynx, vagina, rectum, bladder, etc.

Palpation (from lat. .palpatio- feeling). The method in which groping is applied, i.e. based on the sense of touch. The method of palpation allows you to determine the physical condition of the organs and tissues of the body.

Palpation is carried out with fingertips (pads), without causing pain to the animal. In some cases, palpation can be performed with a fist, hand, back of the hand.

Palpation is divided into superficial and deep.

Superficial palpation is performed by placing the palm or fingertips on the study site, by gently pressing and sliding over the area under study. This method allows you to examine the skin, subcutaneous tissue, lymph nodes, superficial vessels, tendons, muscles, joints, etc. Palpation can determine the local temperature, soreness, configuration and size of the formation, consistency, nature of the surface, etc.

Palpation should always begin with a healthy area of ​​the body, gradually moving to the affected area. The movements of the fingers or palms should be smooth, soft, not causing additional pain to the animal.

Deep palpation is a method by which deeply located organs and foci are examined. Varieties of deep palpation include: penetrating; bimanual; jerky (balloting).

When conducting penetrating palpation with a fist or vertically placed fingers, a gradual but strong pressure is applied through the abdominal wall, reaching the organ under study and determining its physical condition. In this way, the scar, abomasum is examined.

Bimanual palpation(palpation with two hands) is performed on the stomach of small animals. The method consists in simultaneous, gradual pressure with both hands on both sides of the abdominal wall. Research is carried out while standing behind the animal. Bimanual palpation is also used in the study of the pharynx, especially in large animals.

If you suspect the presence of fluid, neoplasms or an enlarged organ in the abdominal cavity, apply jerky (balloting) palpation. With jerky palpation, studies are carried out with jerky movements of the fingers or fist. The palpation technique is as follows: they bring the fingers or fist to the wall of the abdominal cavity and perform a push, while at the end of the push the hand is not taken away from the abdominal wall (this is especially important if ascites is suspected), in the presence of a neoplasm or an enlarged organ, the hand immediately encounters this organ or neoplasm, and in the presence of fluid, a push through the abdominal wall is not felt immediately, but after some time (the return of the fluid that recoiled during the push).

Deep internal palpation allows diagnosing the state of organs located in cavities far from the surface of the body (pharynx, organs of the pelvic and abdominal cavities).

The study of the organs of the pelvic and abdominal cavities through the wall of the rectum is called rectal examination. In large animals, rectal examination is carried out with a hand inserted into the rectum, while in small animals it is possible to examine, at best, the organs of the pelvic cavity, as it is performed with a finger.

Percussion (from lat. percussio- tapping). The method is based on the ability of each tissue or organ to give a characteristic sound during percussion. Depending on the physical state of the organ, this sound can change, and by the nature of the changed sound, one or another state of the organs and tissues of the body is judged.

Percussion is best done indoors, so as not to interfere with extraneous noise. Distinguish between direct and mediocre percussion.

Direct percussion consists in the fact that blows to the place of study are applied directly with a finger or hammer. The maxillary and frontal sinuses are subjected to direct percussion. In other areas of the body, direct percussion is ineffective, since the conditions for the appearance of sounds are negligible.

Direct percussion, carried out with a finger, is called digital, and performed with the help of a percussion hammer - instrumental.

With mediocre percussion, blows to the place of examination are not applied directly to the skin, but through a finger (digital) or a plessimeter (instrumental).

According to the method of striking, topographic and research percussion are distinguished. When, after a blow, a finger or a hammer is slightly delayed on a finger or a plessimeter, this method is called topographic and is used to determine the boundaries of an organ or pathological focus. Jerky percussion, without delay of the hammer or finger, is called staccato and is used to study an organ or focus.

Digital percussion is of particular value in the study of small animals (dogs, cats, small cattle, rabbits, birds, calves, foals, piglets, lean adult pigs). In the study of large animals, digital percussion is not very informative, but can be used in the absence of instruments (plessimeter and hammer).

Digital percussion is carried out by pressing the middle finger of one hand to the place of study and applying short paired blows perpendicular to it with the middle finger of the other hand.

With instrumental percussion, instruments are used - a plessimeter and a percussion hammer. They can be different in shape, mass and performance (Fig. 1.12).

Rice. 1.12. Instruments for percussion of animals of different species: a- percussion hammers; b- plessimeters

The hammer is taken with the thumb and forefinger, and the handle is pressed to the palm with the remaining fingers. The arm is bent at the wrist joint.

Plessimeters with a narrow working platform are most convenient to use, and the size of the malleus depends on the size of the animal. For the study of large animals, large hammers are preferable, for small animals - small ones.

When carrying out instrumental percussion, the plessimeter is pressed tightly against the skin at the place of study (for example, if it is the chest wall, then strictly in the intercostal spaces) and with a percussion hammer, paired blows are applied to it with a small gap and always of the same strength. The blows must be directed perpendicular to the plessimeter. The plessimeter during percussion should be moved one step. In the study of small animals or animals of unsatisfactory fatness, the blows should be weaker. Percussion of the same strength is used when determining the boundaries of an organ or a pathological focus. However, it must be remembered that the percussion method can be used to examine the animal's organs to a depth of up to 7 cm from the body surface, i.e. more deeply located organs and their parts, as well as lesions are inaccessible to percussion examination.

When conducting percussion, the following conditions must be observed: silence, the ear of the researcher (doctor) must be at the same level with the place of percussion, the force of impact and pressure of the pessimeter throughout the percussion must be the same, the animal is recommended to be placed at a distance of no closer than 1 m to avoid sound resonation from the wall.

Percussion determines the boundaries of the organ and focus, which makes it possible to establish their size, as well as to identify changes in the physical properties of organs.

Auscultation (from lat. auscultatio- listening). With the help of auscultation, you can listen to sounds that occur in the organs and cavities of the body of the animal.

Distinguish between direct auscultation, when one or another organ is heard with the ear without instruments, and mediocre, when the organ is used with instruments (phonendoscope, stethoscope, stethophonendoscope) (Fig. 1.13).

Rice. 1.13.

• 1 - pelota; 2 - head of a phonendoscope; 3 - pilot holder;
• 4 - flexible sound duct; 5 - headband; 6 - membrane; 7 - horn of a stethoscope; # - phonendoscope head cover

Direct auscultation is performed as follows: the ear is applied through a sheet or towel (hygienic accessory) to the surface of the animal's body in accordance with the topography of the organs that need to be heard. The advantage of the method is that it can be performed under any conditions; the sounds emitted by the organs are not distorted; allows you to pick up sounds from a relatively large surface of the body (although this possibility is in some cases a disadvantage, since it makes it difficult to accurately determine the source of the sound).

Direct auscultation has found wide application in veterinary practice, especially in the study of large and calm animals.

Mediocre auscultation is carried out using stethoscopes, phonendoscopes, stethophonendoscopes. It allows you to listen to sounds from a more limited area than with direct auscultation. Stethoscopes are used to listen to individual components - heart sounds (for example, with defects), etc.

The narrow end of the cone-shaped extension is applied to the place of study, and the ear is applied to the wide end, the hand is taken away from the stethoscope.

If auscultation is carried out with a phonendoscope with a membrane, then it is necessary to press it tightly against the body of the animal in order to exclude friction of the membrane against the animal's hairline, which can introduce extraneous noise into the main ones coming from the organ under study. This should be especially remembered when examining the valvular apparatus of the heart.

Thermometry. This is a mandatory method of animal research, which is performed when an animal is received, regardless of the goals of the research.

Thermometry is a very important method of clinical research, since most diseases, especially infectious diseases, are initially manifested precisely by a change in body temperature.

To measure body temperature, you can use different thermometers (mercury, electronic). Each thermometer must be checked before use for correct readings. To do this, the tested thermometer is lowered into a vessel with water with a tested control thermometer, after 10 minutes they are removed and the readings of the tested and control thermometers are compared. A thermometer with incorrect readings is discarded.

The internal body temperature of the animal is measured in the rectal cavity. Before the introduction of the thermometer, the readings are checked, disinfected, lubricated with vaseline or vaseline oil. The animal is preliminarily fixed, the tail is lifted and the thermometer is inserted into the rectum with rotational movements, giving it an inclined position so that the tip of the thermometer comes into contact with the mucous membrane, after which it is fixed to the tail with a tail bag, clamp or ribbons.

To measure body temperature in birds, a special “bird thermometer” is used, in which the temperature reading scale is designed for digital values ​​greater than in animals.

Body temperature must be measured both at the initial reception of the animal, and at all subsequent examinations.

In cases where it is not possible to examine the body temperature in the rectum, the thermometer is inserted into the vagina, remembering that the temperature in the vagina is 0.3-0.5 ° C higher than the rectal temperature.

Special research methods. Special methods include: studies conducted in laboratories (laboratory) and performed using special tools and equipment (instrumental). Laboratory studies are subjected to body fluids and tissues. Among the instrumental studies, electrocardiography (ECG), ultrasound examination of the heart (EchoCG), X-ray diagnostics, ultrasound examination (ultrasound), endoscopy (many types), magnetic resonance imaging (MRI), computed tomography (CT), etc. are most often performed.

Special methods in any necessary combination are additional research methods and allow you to clarify the diagnosis.

Special research methods are described in the relevant chapters of this workshop.

In healthy animals, vesicular or pulmonary respiration, physiological bronchial respiration in the tops of the lungs, and laryngotracheal respiration in the larynx and trachea are distinguished.

In pathological processes, a number of additional sounds may occur in the bronchi, alveoli of the lungs, pleura and pleural cavity, such as are not found in the norm.

Identification and differentiation of the main and additional noises that occur during pathology gives an idea of ​​the physical state of the respiratory organs and often of their functional state. Changes in the work of the respiratory organs in pathology are sometimes so significant that they do not cause difficulties in their identification and diagnostic evaluation. However, it should be borne in mind that during auscultation of the respiratory organs, different animals have their own characteristics and difficulties.

auscultation technique. During direct auscultation, the animal's chest is covered with a towel. A towel is necessary not only for hygienic reasons, but also because it partly eliminates the friction noise of wool. To protect yourself from possible damage and reduce the movement of the animal, its head must be fixed, and in restless animals it is recommended to raise the thoracic limb.

The study of the left half of the chest is performed with the right ear, and auscultation of the right half with the left. The specialist in this case becomes facing the head of the animal, and only with auscultation of the posterior parts of the lung can one become facing the rear of the animal. In order to create closer contact, as well as for the purpose of self-defense, the appropriate hand is placed on the withers or back of the animal and held during the entire examination. In small animals, they usually stand behind the animal; this allows auscultation to compare the auscultatory phenomena of both sides during auscultation. With unilateral damage to the lungs and bronchi, this is of great practical importance.

Auscultation is best done in a closed, small room with a soft floor. Auscultation on the street, in the common stables and cowsheds is greatly hampered by extraneous rustles, and in the summer, by insects that disturb the animals.

Despite the fact that the lungs are adjacent to the chest wall of the animal throughout, auscultation is possible only in places less covered by muscles. Parts of the lung, covered with a scapula and powerful muscles of the shoulder, give sounds either sharply weakened, or they are not heard at all. This is especially pronounced in large animals, in which breathing on the chest is normally heard much weaker than in small animals. This encourages auscultation of those parts of the chest where sound phenomena are more pronounced, and then move on to areas where they are less intense and hard to hear.

In the horse, auscultation of the lungs begins with the middle section of the chest, located directly behind the shoulder blade. After listening to this area, they proceed to the study of the mid-posterior chest, then auscultate the upper-middle and upper-posterior segments in turn. Next, the lower-posterior section of the lung is examined. The sections of the lung, hidden under massive muscles, are examined at the end and, often, after comparing the right and left sides. In cattle, the study is carried out in the same order, although it must be said that auscultation through the scapula is much easier than in the horse. In cattle, in addition, the prescapular region is available for auscultation. The study of this area gives an idea of ​​the condition of the tops of the lungs. These departments often turn out to be the site of the development of tuberculous and peripneumonic processes. The area of ​​the oscultation in the prescapular region can be expanded by abducting the leg back. In small animals, all parts of the lung are available for auscultation, with the only difference being that in some places the breath sounds are heard better, while in others they are somewhat weaker.

2-3 phases of breathing are heard, and if no deviations from the norm are found, then they proceed to listening to another area. In case of detection of deviations from normal respiratory noise, it is necessary to establish the nature of these deviations. To do this, you can compare the breath noise with neighboring areas and with homologous points on the opposite side of the chest.

If breathing is not heard or heard very weakly, it is recommended to resort to increased breathing. In the horse, this can be achieved by leading, by lunging, or by closing the nostrils, turning off the breath for a while. In cattle, increased breathing is possible by closing the nostrils with a towel, hands, or using a Rautman clamp. This technique can cause an increase in respiratory noise and correctly assess the changes detected during auscultation.

During auscultation, it is necessary to establish the intensity of respiratory noises, their properties, and if there are pathological noises, to find out their nature and location.

All noises found on the chest from the side of the lungs are divided into main and adnexal. The main breath sounds include vesicular and physiological bronchial and laryngeal breathing; Airborne noises are subdivided into bronchopulmonary and extrapulmonary. Bronchopulmonary rales include dry and moist rales, crepitating rales, crepitus, bronchial pathological breathing, amphoric breathing, and the noise of a falling drop. Extrapulmonary, or pleural, in turn, are divided into pleural friction noise, splash noise and pulmonary fistula noise.

The main methods of clinical examination of the patient include: examination, palpation, percussion, auscultation and thermometry.
Inspection best done in daylight. If necessary, you can use strong white diffused light (artificial). The study of the contours of the body and its individual parts is carried out with side lighting. In some cases, lighting devices (mirror, reflector, endoscope) can be used.
The examination is carried out in a certain sequence: first, the head, neck, then the chest, the iliac region, the abdomen, pelvis, limbs, etc. are examined. At the same time, they try to notice the existing abnormalities in the position of the animal, the shape, size, color and properties of the body surface. In the evaluation of examination data obtained by the method of examination, one often resorts to comparing one part of the body with the corresponding opposite.
Inspection can be a very valuable way of mass animal research. So, for example, against the background of a healthy herd, it is easy to notice sick people who usually lag behind others, eat poorly feed, are depressed and show other symptoms or signs of illness.
Palpation(palpation) of organs and tissues establish the nature of their surface, temperature, consistency, shape, size and sensitivity. This method provides objective data in a comparative study of the healthy side with the patient. It is better to start palpation from healthy areas and from the healthy side, and then move on to the diseased side and to the diseased area. Palpation can be done directly with the fingers and with instruments (eg, trial hoof forceps, probes). There are deep and superficial palpation.
superficial palpation is performed by light touches and sliding on the skin of the palm. It can be used to determine the quality of the heart beat, chest vibration, skin surface temperature, pain reaction, muscle tension. It is used to study pulsating vessels.
Deep palpation is the palpation of tissues and organs with the ends of the fingers by gradually increasing pressure. This type of palpation is used in the study of organs located in the abdominal cavity (stomach, intestines, liver, spleen and kidneys), especially in small and medium-sized animals. A variety of deep palpation includes penetrating and jerky palpation.
Penetrating palpation is performed with vertically placed fingers with constant but strong pressure in a limited place (according to the topographic location of the organ under study).
Jerky palpation consists of short and strong jolts applied with the fingers. It is used to determine the fluid in the cavities, as well as in the study of the liver and spleen. In the presence of fluid in the abdominal cavity, swaying is observed, and in case of disease of these organs, their soreness is manifested.
Percussion(percussion) is the study of animals by the method of percussion. By the nature of the sounds resulting from percussion, it is possible to judge the state of the organs. Distinguish between direct and mediocre percussion.
Immediate percussion consists in short blows to the examined part of the body, applied by one or more fingers folded together and slightly bent.
In this way, the frontal and maxillary sinuses are often examined. It is also used in cases where it is necessary to obtain not only sound, but also tactile impressions. Mediocre percussion can be digital and instrumental.
Digital percussion is performed with a slightly bent middle finger of the right hand along the terminal phalanx of the index or middle finger of the left hand, tightly attached to the corresponding part of the body (it acts as a plessimeter). Blows should be short and jerky.
In veterinary practice, digital percussion is applicable to the study of small animals, calves and long-haired sheep and goats.
instrumental percussion - percussion with a percussion hammer and a plessimeter (Fig. 10). As a plessimeter, plates of various shapes and sizes are used, made of metal, wood, bone and plastic.

Percussion of the lungs in various animal species

Through percussion establish:

1) topography of the lungs;

2) the physical condition of the lungs and pleural cavity;

3) soreness of the costal wall and deeper lying organs.

Let's start with topographic percussion of the lungs, i.e. establishing the boundaries of the body. First of all, you need to know that only the posterior border of the lungs is of diagnostic value, since the upper and anterior are not the anatomical boundaries of the organ. The upper border of the lung is considered to be a horizontal line at a palm-width distance in large and 2-3 fingers in small animals from the spinous processes of the thoracic vertebrae. The anterior border is considered to be the line from the posterior angle of the scapula down along the anconeus line.

To determine the posterior border of the lung on the chest, mentally draw three horizontal lines.

The first is along the maklok line.

The second - along the line of the ischial tuberosity (in cattle, lines 1 and 2 coincide).

The third - along the line of the scapular-shoulder joint. Percussion is carried out strictly along the marked lines from front to back, i.e. begin immediately behind the scapula and move caudally along the intercostal space. In this case, mediocre instrumental percussion is used in the study of large animals and mediocre digital - in the study of small animals or young animals. The blows are not strong, the hammer lingers on the plessimeter (legato percussion).

The posterior border of the lung is determined by the transition of a clear pulmonary sound to any other (tympanic, dull). The last intercostal space, where a clear pulmonary sound is established, is considered the posterior border. So, in cattle and small cattle, the posterior border of the lung along the maklok line in the 11th intercostal space on the left and the 10th intercostal space on the right, and along the line of the scapular-shoulder joint - in the 8th intercostal space on both sides. In the horse: along the line of the maklok - 16, along the line of the ischial tuberosity - 14, along the line of the scapular-shoulder joint - 10th intercostal space.

The general displacement of the posterior border of the lung caudally or rollback of the lung indicates its increase. The most significant (on 1-2 ribs) it occurs in acute and chronic alveolar emphysema. A less pronounced shift is observed with interstitial emphysema. With pneumothorax, when air enters the pleural cavity, the posterior border passes along the line of attachment of the diaphragm or rolls away from it by 2-4 cm.

Partial displacement of the posterior border (along 1 or 2 lines) also indicates damage to the lung parenchyma and is noted with focal (vicarious) emphysema. It should also be borne in mind that the general and partial rollback of the lung can be one- or two-sided.

The displacement of the posterior border of the lung cranially (forward) most often does not indicate the pathology of the lung tissue itself. This condition is observed with pathology from the organs located in the abdominal cavity (gastric dilatation, tympania, hepatomegaly, neoplasms in the kidneys, hydronephrosis) or in females with deep pregnancy.

Assessment of the physical condition of the parenchyma is carried out by percussion of the pulmonary field. In most animals, there is only one lung percussion field - this is the area located behind the scapula (in the horse it is called the percussion triangle). Cattle have two of them: one is located behind the shoulder blade, and the other is in front of the shoulder blade. This prescapular percussion field is small, it is found in front of the scapular-shoulder joint, above the tubercle for 5-8 cm. In this case, the thoracic limb should be moved back.

Percussion technique in assessing the physical condition of the lung tissue: conduct instrumental mediocre percussion; inflict strong, short and jerky blows (stokkato percussion); percussion is carried out along the intercostal spaces from top to bottom, starting immediately behind the scapula, then shifted 1 intercostal space caudally, then another 1 intercostal space - and so on throughout the percussion field of the lungs.

A percussion blow penetrates to a depth of up to 7 cm. Considering that the thickness of the chest wall in large animals is 3-4 cm, it is actually possible to examine the organ to a depth of the same 3-4 cm, i.e. only superficial lesions are found.

When percussion of the pulmonary field in healthy animals, only one is found - a clear pulmonary sound. In pathology, other sounds can also be detected: dull, dull, tympanic, a sound with a metallic tinge, the sound of a cracked vessel (pot).

Dull and dull sounds have the same origin and differ from each other only in the degree of expression. A dull sound indicates the absence of air in the lung tissue or the accumulation of significant amounts of fluid in the pleural cavity. It is quiet, short and low.

A dull sound is somewhat stronger, higher and clearer than a dull sound, since it occurs if gases are present in the lung or pleural cavity along with liquid. Usually this is observed at the very beginning of the development of the disease or vice versa, at the end of the disease. Dull and dull sounds are established in the syndrome of infiltrative compaction of the lung tissue and the syndrome of fluid accumulation in the pleural cavity, which we will discuss in more detail later.

Tympanic sound is produced by percussion of air-filled cavities. It is loud, low and long. Tympanic sound is detected with pneumothorax (accumulation of gas in the pleural cavity), putrefactive pleurisy, the formation of cavities in the lung (cavities filled with air).

In addition, tympanic sound is found in alveolar and interstitial emphysema, when the alveoli are torn with the formation of significant air spaces or such cavities are formed in the interalveolar tissue. If such a cavity has dense, smooth walls and the air pressure in it is high, then a sound with a metallic tint can be established. It is installed in chronic alveolar or interstitial emphysema, valvular pneumothorax, diaphragmatic hernia.

The sound of a cracked vessel is a kind of rattling sound. It is installed in the presence of smooth-walled cavities in the lungs that communicate with large bronchi. It should be borne in mind that such a sound can also be obtained when the plessimeter is loosely applied to the chest wall, especially in animals of poor fatness.

Auscultation of the lungs

Basic (physiological) and adnexal (pathological) breath sounds. Auscultation of the lungs allows you to detect sound phenomena that occur in the lungs during breathing, evaluate their nature, strength, localization and relation to the phases of breathing. Listening in large animals can be carried out directly, but mediocre auscultation is much more convenient, using a phonendoscope, stethoscope or stethophonendoscope.

It is recommended to start auscultation from areas where breath sounds are best expressed, and then move on to places where breathing is less pronounced (draw a triangle with areas that are sequentially listened to). In cattle, one should also listen to the prescapular pulmonary percussion field. At each point, it is enough to listen to 3-4 respiratory movements (inhale-exhale), after which you should move the phonendoscope capsule to another place.

It is advisable to listen to the lungs in two steps. Initially, an approximate auscultation of the entire region of the lungs on the right and left is carried out. This allows you to get information about the condition of the entire lung and the presence of any abnormalities. Next, it is necessary to listen in detail to the areas where pathological sound phenomena are noted or where changes can be assumed based on the results of examination, palpation and percussion.

When auscultating the lungs, it is necessary to first determine the nature of the main (physiological) noise, and then the presence of possible adnexal (pathological) noises.

Basic (physiological) breath sounds. Above the lungs in healthy animals, two respiratory sounds are heard: vesicular and physiological bronchial. Bronchial murmur is absent on the chest in horses and camels; its presence in these animals always indicates lung pathology.

Vesicular breathing is heard over most of the surface of the lung and can also be called alveolar, because. occurs in the alveoli of the lung as a result of the rapid straightening of their walls when air enters during inhalation and their decline during exhalation. At the same time, the walls of the alveoli come into tension and, oscillating, produce a sound characteristic of vesicular respiration.

Vesicular noise has the following features:

1. It is soft in character, reminiscent of the sound when the letter "F" is pronounced and at the same time the air is slightly drawn in.

2. It is heard throughout the entire period of inhalation and only at the beginning of exhalation. This happens because inhalation is the active phase of breathing, in which the walls of the alveoli gradually straighten out. Exhalation is passive, the walls of the alveoli quickly subside and therefore the vesicular noise is heard only at the very beginning of exhalation.

In healthy animals, vesicular breathing on the chest is heard with unequal strength. It is most intense just behind the scapula in the middle part of the lung percussion field. In the horse, the vesicular murmur is gentle, soft, and weak. In large and small cattle it is rather rough and loud, in sheep and goats it is also heard on the shoulder blade. In dogs and cats - the most intense, sharp and close to bronchial breathing. It should also be borne in mind that the vesicular noise in young animals is louder and rougher than in adults, and even more so in older animals.

There are weakening and strengthening of vesicular respiration, which, in turn, can be physiological and pathological. Physiological weakening is a consequence of a deterioration in the conduction of sounds, for example, with above-average fatness or obesity of the animal. At the same time, breathing is weakened evenly over the entire surface of the lung. Physiological enhancement of vesicular respiration occurs during exercise, as well as in the presence of a thin chest wall (in young animals).

Pathological weakening of vesicular respiration occurs in diseases of both the lungs and the pleura. A pronounced uniform weakening occurs with emphysema, tk. the elasticity of the lung tissue decreases and the alveoli are filled with air. With focal (lobular) pneumonia, at the beginning of lobar pneumonia, part of the alveoli is turned off from the breath and breathing also weakens. The same picture is observed in the syndrome of fluid accumulation in the pleural cavity, when fluid accumulates (exudate - exudative pleurisy, transudate - dropsy, blood - hemothorax). Weakening, up to the complete absence, of vesicular breathing is observed with pneumothorax (accumulation of air in the pleural cavity), with chest injuries, especially with fractures of the ribs.

Pathological increase in vesicular respiration may be the result of a compensatory mechanism on the part of a healthy lung. This happens with unilateral croupous pneumonia, exudative pleurisy, hydro- or hemothorax, i.e. on the affected side, breathing is weakened, and on the healthy side, on the contrary, it is increased.

If there is a sharp and uneven narrowing of the lumen of the small bronchi and bronchioles due to inflammatory edema of their mucous membrane (bronchitis, bronchopneumonia), then breathing is heard both on inhalation and on exhalation. It acquires a rough, hard character and is called hard breathing. Bronchial physiological breathing is a kind of laryngotracheal, audible on the chest in the bronchi. This is a coarse respiratory noise resembling the sound "X m", which is heard both on inspiration and on expiration. Bronchial physiological respiration is heard in all animals (with the exception of a horse and a camel) in the area of ​​the shoulder girdle up to 3-4 intercostal spaces, and in dogs - throughout the chest.

Adnexal (pathological) breath sounds. Adnexal (pathological) noises include sounds that are formed in excess of the main respiratory noises in the lungs. There are bronchopulmonary adnexal noises that form in the lungs - wheezing, crepitation, crepitating wheezing, pathological bronchial breathing and extrapulmonary (pleural) noises that form outside the lungs - these are friction and splash noises.

Bronchopulmonary adnexal breath sounds. Adnexal (pathological) bronchopulmonary murmurs include, first of all, wheezing. These are additional breath sounds that occur in the airways of the lungs in pathology. They are formed in the following cases:

1) the presence of liquid content in the bronchi, alveoli or pathological cavities;

2) violation of bronchial patency (bronchospasm, swelling of the mucous membrane);

3) damage to the walls of the alveoli, or bronchioles.

According to the mechanism of formation and sound perception, wheezing is divided into dry and wet.

Dry rales are formed only in the bronchi. They occur when the lumen of the bronchi narrows or when there is a viscous secret in them, located in the form of threads, films and jumpers. Air, passing through these areas, forms eddies, cycles, etc. what is perceived as whistling, buzzing, buzzing, etc.

Dry rales are divided into low and high. Low ones are buzzing and buzzing, they are formed in large and medium bronchi. High - it's luminous, occur in the small bronchi and bronchioles. Dry rales are heard in both phases of breathing - on inhalation and exhalation, after physical exertion they become louder.

Moist rales occur when fluid accumulates in the airways (exudate, transudate, bronchial secretion, blood). They are caused by the formation of rapidly bursting air bubbles when air passes through a liquid secret. The sound accompanying the rupture of air bubbles on the surface of the liquid is heard during auscultation as wheezing. Wet rales are heard mainly on inspiration, because. during inhalation, the airflow velocity is the highest.

The size of the resulting air bubbles depends on the diameter (caliber) of the bronchi or the size of the pathological cavity in which wheezing is formed. If wet rales occur in the alveoli, bronchioles and the smallest bronchi, then they resemble the sound of bursting bubbles in a glass of carbonated water and are called fine bubbling. These rales are heard with bronchopneumonia, soaking of the lung with blood (pulmonary infarction), at the beginning of pulmonary edema (phase of auscultatory manifestations).

With the formation of moist rales in the bronchi of medium caliber or small cavities, they are perceived as the sound of air bubbles blown through the liquid through a thin straw. Such wheezes are called medium bubbling. They are detected in pneumonia with multiple small abscesses, pulmonary edema.

If rales are formed in the large bronchi, in the pulmonary caverns, which contain effusion fluids, then loud and prolonged sounds are heard, which are called coarse rales. They are detected most often with pulmonary hemorrhage, macrobronchitis.

The nature of both dry and wet rales can change under the influence of coughing, during the development of the pathological process. So, for example, with bronchitis, dry, wet, then again dry can be heard alternately.

Crepitus - the sound formed in the alveoli during inflammation, similar to a crackle or crunch. They listen to crepitus more often with inflammation of the lung, as a result of which the walls of the alveoli are compacted and covered from the inside with a layer of sticky exudate. In this case, on exhalation, the alveoli collapse and stick together. On inspiration (at its height), the walls of the alveoli are sticking and is accompanied by the formation of a peculiar sound resembling a crack.

Crepitant rales resemble a crunch, crackle. They are sharp, rough and appear with emphysema. In this case, the walls of the alveoli and bronchioles are damaged, air penetrates into the interstitial tissue, and the resulting air bubbles, when exhaled, move towards the root of the lung, destroying the lung tissue. The presence of crepitant wheezing is a sign of severe damage to the lung tissue.

In the differential diagnostic assessment of moist and crepitant rales, as well as crepitus, the following features should be taken into account:

1) moist rales are heard in both phases of breathing;

2) moist rales after coughing weaken or even disappear;

3) crepitant rales are heard during exhalation, do not change after coughing;

4) crepitus appears on inspiration.

Bronchial pathological breathing is bronchial breathing heard on the chest in animals behind (caudal) 3-4 intercostal spaces, and in horses on the entire chest. The cause of this noise is the compaction of the lung tissue with simultaneously free bronchi. It is noted with emphysema, in the initial stage of infiltration of the lung parenchyma, with narrowing of the bronchial lumen.

Amphoric respiratory noise is detected in the presence of cavities or cavities in the lungs (at least 5-6 cm in diameter) with smooth, even walls, which communicates with a large bronchus. According to the laws of resonance, this cavity amplifies sound phenomena, and its compacted walls conduct noise well, which resembles a puff of air over a vessel with a narrow neck, such as a bottle. Such noise occurs with tuberculosis, lung gangrene, extensive bronchiectasis.

Extrapulmonary (pleural) breath sounds. Pleural friction noise is a sound formed between the sheets of a pathologically altered pleura: with dry pleurisy, sharp dryness of the pleural sheets due to the rapid loss of a large amount of fluid by the body (diarrheal syndrome, exsicosis syndrome, dyspeptic neonatal syndrome, with massive blood loss). This noise is reminiscent of the creaking of skin or the creaking of freshly fallen snow in frosty weather. Pleural friction rub should be differentiated from crepitus and moist, finely bubbling rales. The main differences are as follows: the pleural friction noise is heard both on inspiration and on expiration; is heard directly under the capsule with a phonendoscope, i.e. superficial; aggravated by pressure with a phonendoscope; does not change when the patient coughs; often accompanied by severe pain and, as a consequence, saccaded breathing. Splashing noise occurs if there is fluid and some gas in the pleural cavity. It is noted with purulent-putrefactive pleurisy. The noise of a pulmonary fistula occurs when cavities form in the lung, which open into the pleural cavity below the level of fluid accumulated there. This noise resembles a gurgling or gurgling during the inhalation phase, it is rare in pulmonary gangrene in horses, with rampant pneumonia in cattle.

Special and functional methods for the study of the respiratory system

X-ray examination.

X-rays are used more often, and fluoroscopy is somewhat less common. In veterinary medicine, a special X-ray method has been developed - fluorography. The main radiological symptoms of the pathology of the lungs and pleura in animals are darkening and enlightenment of the lung field. When evaluating these symptoms, attention is paid to their location, size, shape, structure and contrast. Endoscopic methods. Rhinoscopy, laryngoscopy, bronchoscopy.

Graphic methods.

Pneumography is a graphical recording of breathing or respiratory movements of the chest. According to the pneumogram, you can set the frequency, strength and rhythm of breathing, the duration of the inhalation and exhalation phases. Rhinography is a graphic recording of a jet of exhaled air. Allows you to judge the ventilation of the lungs.

operational methods.

Tracheotomy, intracheal injections (tracheopuncture), thoracocentesis.

Functional methods for studying the respiratory system allow you to evaluate the function of the respiratory system. There are two main methods: the exercise test (designed for the horse) and the apnea test (for other animal species) - we will consider when studying the cardiovascular system.

Load test.

Calculate the frequency of respiratory movements in the horse at rest. Then trotting for 10-15 minutes and immediately count the number of respiratory movements again. In healthy people, breathing quickens to 20-24 per minute. and returns to the original after 7-10 minutes. With functional insufficiency of the respiratory system, the frequency increases to 45 and does not return to the original after 20-30 minutes or more.

Plegaphonia or tracheal percussion. Apply this method to assess the physical condition of the lung tissue and differential diagnosis of lobar pneumonia from exudative pleurisy. Technique: carried out together, one person (assistant) delivers rhythmic, moderate-strength short blows to the plessimeter applied to the trachea; the other (researcher) assesses the strength of the conducted percussion sounds through auscultation of the chest.

The main syndromes of respiratory diseases

The syndrome of infiltrative compaction of the lung tissue (pulmonary infiltration) is a pathological condition caused by the penetration into the tissues of the lung and the accumulation of cellular elements and fluids in them. Impregnation of lung tissues only with biological fluids, without admixture of cellular elements, is characteristic of pulmonary edema, and not infiltration. In pathology, infiltration of the lungs of inflammatory origin is more common. It can be macrophage, leukocyte (lymphocytic, eosinophilic), hemorrhagic, etc. It is accompanied by a moderate increase in the volume of lung tissue and its increased density.

The main symptoms of infiltration: cough; shortness of breath with polypnoea; fever; dullness of percussion sound; alveolar crepitus at the height of inspiration, dry and moist rales. At the beginning of the development of the process, the cough is dry. Subsequently, the cough becomes wet with the release of mucous, mucopurulent sputum, sometimes with blood. Foci of dullness are found in cases where the infiltrate is adjacent directly to the chest wall or is located at a depth not exceeding the resolving capabilities of deep percussion.

Fluid accumulation syndrome in the pleural cavity is a clinical and laboratory syndrome caused by fluid that accumulates in the pleural cavity due to damage to the pleura lining it or due to general disturbances in water and electrolyte metabolism in the body. In most cases, pleurisy and its nosological forms are not an independent disease, but a complication of diseases of the lungs, chest wall, diaphragm (with its perforation).

Symptoms of fluid accumulation in the pleural cavity: dullness of percussion sound on the chest with a horizontal upper border; mixed shortness of breath with a predominance of abdominal breathing; cyanosis; swelling of the jugular veins; sometimes splashing noise. With thoracocentesis - exudate, transudate, blood, chylous fluid.

The syndrome develops with exudative pleurisy (acute in horses and sheep, chronically in cattle and pigs), hydrothorax, hemothorax, chylothorax. Hydrothorax can be caused by heart failure of various origins: decompensated heart defects, compressive pericarditis, damage to the heart muscle. It occurs in diseases accompanied by severe hypoproteinemia (alimentary dystrophy, toxic liver dystrophy, severe anemia, nephrotic syndrome).

Pulmonary expansion syndrome (increased airiness of the lungs) is a pathological condition characterized by the expansion of either the air spaces of the lungs located distally to the terminal bronchioles, or the interlobular connective tissue when air enters it.

The appearance of symptoms and the development of the syndrome depend on the severity, severity, period of the underlying disease and the degree of involvement of the lungs in the process. The rollback of the posterior border of one lung can be compensatory in case of damage to the other as a result of obstructive and compression atelectasis, with unilateral pneumonia.

The developed syndrome includes the following main symptoms: expiratory or mixed shortness of breath; barrel chest; dry or wet cough; rollback of the posterior border of the lungs, a loud boxed percussion sound; weakening of vesicular respiration. The syndrome develops with chronic alveolar emphysema in working and sport horses, in hunting dogs, if there is no complete recovery from acute emphysema. It can occur as a complication in inflammatory, stenotic and spastic lesions of the larynx and bronchi, in chronic pneumonia and allergies.

In cattle, the syndrome often manifests itself with interstitial emphysema, which complicates chronic pulmonary tuberculosis, or as a result of injury to the lungs by foreign stabbing objects from the side of the proventriculus. Sometimes subcutaneous emphysema occurs in the neck and chest.

Respiratory failure is a pathological condition in which the respiratory organs are not able to provide normal gas exchange, or the gas composition of the blood is maintained due to the increased work of the lungs and heart. Respiratory insufficiency can be caused by damage to: - the bronchi and the lung parenchyma proper;

Pleura, muscles and bones of the chest wall;

Respiratory center of the brain.

In this case, acute and chronic respiratory failure are distinguished. Acute respiratory (pulmonary) insufficiency is a critical pathological condition of the body, in which the imbalance of the gas composition of arterial blood rapidly increases due to the cessation of oxygen supply to the blood and the removal of carbon dioxide from the blood. If intensive therapeutic (resuscitation) measures are not carried out during ARF, then this condition ends with cessation of breathing or asphyxia.

Symptoms of ARF - shortness of breath, central cyanosis, anxiety, alternating with lethargy, lack of consciousness, convulsions, warm skin. Cyanosis is a bluish discoloration of the skin and mucous membranes. It is caused by a high content of reduced hemoglobin in the blood. In this case, the following is characteristic of central cyanosis:

1) it is diffuse;

2) non-pigmented areas of the skin have an ash-gray tint;

3) the skin is warm due to accelerated blood flow.

Unlike central cyanosis, peripheral cyanosis is caused by a slowdown in blood flow and therefore the skin is cold to the touch, observed in diseases of the cardiovascular system. This cyanosis is often referred to as acrocyanosis and is most pronounced on the limbs and pinnae of animals.

The most common causes of ARF are:

Aspiration of foreign bodies;

Pulmonary embolism;

Inhibition of the respiratory center (in case of poisoning);

Extensive and severe injuries of the chest wall and pleura;

Laryngo- and bronchospasm.

Chronic DN is characterized by a gradual increase in gas exchange disorders. The most pronounced symptoms of CRF in animals appear after exercise. After work or a short run (even walking), shortness of breath (expiratory or inspiratory), cyanosis, polypnea, shallow breathing, symptoms of heart failure are established. These signs in the animal disappear only after a long rest. If these symptoms are detected in the animal even at rest, then this indicates decompensated pulmonary heart failure. This usually occurs with the development of a bronchopulmonary infection in a patient with emphysema.

Diagnostic value of the study of exudate and transudate

Fluids that accumulate in the pleural and other body cavities are divided into exudates and transudates. They are obtained for research through a puncture of the chest wall (thoracocentesis). It is performed according to all the rules of surgical technique with a special needle or trocar, which are equipped with a tap so that air does not enter the pleural cavity. You can also use an ordinary needle connected to a syringe.

The puncture site in ruminants and pigs is the 6th intercostal space on the left and the fifth on the right, in the horse, respectively, 7 on the left and 6 on the right, slightly above the external thoracic vein. The needle is injected to a depth of 3-4 cm in large animals and 1-2 cm in small animals, until the resistance suddenly decreases.

The effusive fluid thus obtained is placed in a clean, dry dish, stabilizers are added (sodium citrate - 1 mg / ml, heparin) and subjected to research. In this case, physical properties are determined, such as color, transparency, relative density. A chemical study is also carried out with the determination of protein and a Rivalta test is performed to differentiate exudate from transudate. Methods of microscopy and bacterioscopy have also been developed.

Transudates appear due to the following reasons:

changes in the vascular walls;

increase in capillary pressure;

hydrodynamic changes.

Usually transudate is a colorless or slightly yellowish, transparent liquid, watery consistency, odorless, slightly alkaline reaction. The relative density of the liquid ranges from 1.002 to 1.015 g/ml. The protein content in the transudate does not exceed 25 g/l (2.5%). Revolt's test is negative, the sediment is insignificant.

Exudates are formed as a result of inflammatory processes. The color depends on the type of inflammation, the liquid is cloudy, viscous and thick, often with an unpleasant putrid odor. The relative density of the exudate is more than 1.015 g/ml, the protein concentration is more than 25-30 g/l (2.5-3.0%). The Rivolta test is positive, abundant sediment, there are a lot of leukocytes and erythrocytes in the smears.

Serous exudates are transparent, yellow in color with a protein concentration of about 30 g/L. Purulent exudates are turbid, yellow-green in color, with a high relative density and a protein content of 70-80 g/l. Hemorrhagic exudates of brown-red color. In case of infection, there may be a combination of hemorrhagic exudate with purulent.

The protein content in effusion fluids is determined by refractometric or colorimetric method with sulfosalicylic acid. The Rivolta test is used for rapid differentiation of exudates from transudates. The principle is based on the fact that exudates contain seromucin, a substance of globulin nature, which gives a positive reaction. Sample setting: in a cylinder with 100 ml of distilled water, acidified with 2-3 drops of concentrated acetic acid, add 1-2 drops of the test liquid. If the resulting whitish cloud descends to the bottom of the cylinder, the sample is positive (exudate), if the cloud dissolves, it is negative (transudate).

Rivalta's test does not always allow distinguishing transudate from exudate when examining mixed fluids. Microscopic examination is of great importance for their difference. For this, a preparation is prepared from the liquid sediment (obtained by centrifugation), the cells are examined natively (without staining) or stained according to Romanovsky. At the same time, transudates contain few erythrocytes and leukocytes, and their number is significant in exudates. During bacterioscopy, preparations from the sediment of the liquid are stained according to Gram or Ziehl-Neelsen.