Percussion of the heart. Medical diagnostic methods
Percussion of the heart and to this day retains its importance in identifying diseases of internal organs, despite the emergence of more modern diagnostic procedures and manipulations.
It refers to objective methods of examination and is based on the physical ability of different in density and elasticity of media to emit sound vibrations that are different in timbre.
The term "percussion" originated from the Latin word "hit, knock." Even the doctors of ancient times tried to investigate the appearance of pathological fluids and gases in the abdomen using a similar method.
Already later, in the mid-18th century, Auenbrugger developed a whole method of applying such a physical technique in the diagnosis of diseases of internal organs.
Percussion of the heart, its modification and improvement began to be made in the early 20th century, when a plysimeter and a special percussion hammer were offered as auxiliary means.
The basis of the method is as follows.When percussion on a certain part of the body with the ear, you can listen to different sound vibrations. Density, elasticity and other specific properties of the fabric directly affect the pitch of the sound produced. The lower and shorter it is, the denser the underlying medium, the higher and longer it is, the more airy the body. Loudness is directly proportional to the strength of the strikes.
Percussion above the lungs in the norm gives a clear sound. In the presence of pathological processes in them, for example, atelectasis, infiltration, the sound becomes dull and quiet.
The next variation that can be identified with percussion is the tympanic sound. Appears over areas of cavities filled with air, both in normal above the stomach and in pathology, for example, over the area of exposed lung abscess.
Blunt sound is typical when defining the boundaries of the heart, as well as the liver, muscles, bones and other dense formations.
There are direct and indirect methods of percussion. The first is carried out by applying short strokes on the study surface with pads of end phalanges.In the second method, a finger-gauge or auxiliary metal, wood and other plates are used to replace the latter.
By force, there are quiet, medium and loud variants of percussion, each of which carries its own diagnostic load in a particular case. For example, when conducting a method such as heart percussion, the first two kinds of it are used. In determining the relative dullness of the heart, the medium is used, and in identifying the absolute - the quiet and the quietest.
Borders, size and configuration of the heart, as well as its vascular bundle are the main purpose of this examination.
As mentioned earlier, the heart normally has 2 dullness due to the appearance of a dull percussion sound over these areas. They are divided into absolute and relative.
The first is represented by the right ventricle, the surface of which is normally not covered by the lungs, and is manifested by the appearance of a dull sound in a given place.
The second corresponds to the present heart boundaries and is heard as a dulling of sound vibrations due to increased airiness against the background of the presence of lung tissue around.
Rules of conducting
Heart percussion should be performed according to the canons established for it. First of all it concerns the position of the doctor and the patient. The pose of the subject is vertical, the arms are located along the body. If this is not possible, the study is carried out in a horizontal position.
The position of the doctor should also be appropriate for the patient - standing or sitting, for more convenient execution of manipulations. To minimize the results of the error in the room should be warm and quiet.
Percussion of the heart is applied finger method. There are some subtleties in conducting the survey.
The first is that the finger, which will be applied intermittent blows, must fit snugly to the percussion surface.
The second nuance is its location. The finger is always parallel to the intended boundary of the body.
The third feature - the step of the finger should be directed from a clear sound to a blunt one. With reference to such a method as percussion of the heart, the boundaries of the organ should be determined by transferring a pleesimeter from the side of the lungs, which covers all relative cardiac dullness.Accordingly, in determining these boundaries, which will be considered true, a pulmonary sound with a dullness should be heard.
In contrast, a dull sound is revealed over the absolute cardiac dullness due to the absence of lung tissue in this area. As mentioned above, they use the quietest and quietest versions of the method.
The fourth feature - the order of. Borders should be defined strictly in the generally accepted sequence. At the very beginning, the right, left, and upper boundaries of relative stupidity are revealed. Then go to its absolute value.
The fifth important point is that the boundaries are marked on the outer edge of the finger - the plysimeter, oriented towards the clear sound.
The study also includes determining the configuration of the organ and the parameters of its vascular bundle, which can be of great importance for such a clinical method as heart percussion.
The norm for borders is generally accepted in accordance with the parameters of average surveys. In accordance with it, the right relative border is made by the right atrium and is located along the same edge of the sternum.Can speak for him, but not more than 1 cm.
The left relative circuit is represented by the left ventricle. It is determined to the left at the level of the apical impulse inwards from the midclavicular line by 1–1.5 cm.
The upper limit is the left atrium, more precisely, its ear. It is defined on edge 3 edges, also at the left.
Heart percussion continues to reveal the contours of his absolute stupidity. In practice, this is done as follows. The previously marked boundaries are reference points from which to begin to be percussed. The technique is completely identical to that described above.
Borders are normally located 1-2 cm inwards from relative dullness and fully correspond to the right ventricle.
Along with percussion, palpation of the heart, or rather, its apical and cardiac impulses, is also performed. The second should not be, and the first corresponds to the left relative border of cardiac dullness in the 5th intercostal space.
Definition of violations
Interpretation of the results makes it possible to evaluate not only cardiac pathology, due to which cardiac boundaries displacements can appear both upward and downward.This may be due to valvular pathologies, myocardial diseases.
Extracardiac causes can include both types of constitution and disorders of other internal organs, including tumor, inflammatory and other pathological processes.
In such cases, a different physical examination method, auscultation, may come to the aid of the diagnosis.
Thanks to him, with a high degree of probability one can suspect the cause of the revealed deviations. Percussion and auscultation of the heart when correctly used are indispensable assistants to the practitioner.
What else can be determined using the method
The diameter of the heart is determined by measuring the length between the right and left borders of the relative dullness of the heart. Its normal size is 11–13 cm.
When conducting percussion, the size of the vascular bundle, represented by the aorta, superior vena cava and pulmonary artery trunk, is also detected. Its norm is 5–6 cm at level 2 of the intercostal space on both sides. The deviation of its parameters indicates the presence of changes on the part of the heart, and as a result of other extracardiac pathology.