Rhonchi

Rhonchi (ronchi), abnormal respiratory sounds. They can occur throughout the entire bronchopulmonary system, starting from the larynx and ending with the alveoli. Rhonchi are formed due to the movement of liquid and semi-liquid masses (mucus, blood, edema fluid) caused by the air stream during the breathing process. For listening to rhonchi, calm, even breathing is recommended; sometimes rhonchi are better detected with enhanced breathing. Very often, rhonchi are first detected and become clear only after coughing. The abnormal respiratory sounds detected by auscultation should be divided into 3 groups: 1) those occurring in the bronchi, 2) those occurring in the lung parenchyma, and 3) those occurring in the pleura. The character of rhonchi occurring in the bronchi depends on the caliber of the bronchus and on the quantity and quality of the secretion. If the secretion released by the inflamed mucous membrane is sticky and viscous, and is difficult to separate from the bronchial wall, conditions are created in which the bronchial lumen becomes narrowed in places. The inhaled air, passing forcefully through the narrowed opening, causes the appearance of dry, whistling rhonchi. Sometimes mucus in inflamed bronchi is arranged in the form of long, dense threads, which are set in motion by the air passing through the bronchi. The vibrations of the mucus threads are accompanied by whistling sounds. Depending on the caliber of the bronchi, two types of dry rhonchi are distinguished: lower-pitched, gurgling-ronchi sonores, and higher-pitched, whistling-ronchi sibilantes. Often both types of dry rhonchi occur together. Such a combination with predominant localization in the lower parts of the lungs is observed in bronchitis. Limited localization of dry rhonchi at the apex of the lungs suggests tuberculous involvement. In cases where dry rhonchi are detected under the angle of the scapula or along the edge of the lung upon repeated examinations, the presence of bronchiectasis or an area of unresolved pneumonia can be assumed. Detailed auscultation sometimes reveals dry rhonchi only during exhalation. Scattered throughout the lung, they are characteristic of emphysema and bronchial asthma. Such rhonchi during exhalation are often found over the apex of the lung in old tuberculous scars in the center of the apex with compensatory emphysema around the focus. If a prolonged whistling rhonchi is accompanied by difficulty in inspiration and is heard throughout the entire lung, then stenosis in the upper respiratory tract should be suspected. The group of dry rhonchi should also include short, crackling, sometimes gurgling crepitation, simulating the sound of pleural friction. Turban, describing this abnormal sound, calls it Knattern (crackling, rustling). Rubel calls these rhonchi ronchi stertorosi. Over cavities, bronchiectases, these crackling rhonchi acquire a metallic tint; over cavities, one can also hear sobbing and squeaking, reminiscent of the yelping of puppies. These varieties of dry rhonchi occur in old scarred processes, which is why Deyke called them 'old rhonchi.' As already indicated, the character of rhonchi is determined by the viscosity of the secretion. Liquid secretion from the bronchial mucosa creates conditions for the appearance of wet rhonchi. In these cases, air bubbles move in the liquid contents of the bronchus, and depending on the caliber of the bronchus, 'wet' large-, medium-, and small-bubble rhonchi are obtained. The latter are otherwise called crepitant rhonchi (see Crepitation). Wet rhonchi are audible in both phases of respiration, but they are still more distinctly heard during inspiration, as the latter occurs more energetically. Rhonchi acquire a ringing, resonant character if the surrounding lung tissue is condensed, and thus conditions are created for resonance. Skoda called resonant rhonchi consonant rhonchi. In non-consonant, non-resonant rhonchi, the bronchial network is surrounded by airy lung tissue. When listening to consonant, resonant rhonchi, the impression is created that they form directly under the stethoscope. Thanks to resonance, they are close to the ear. It should be noted that large rhonchi are few in number, and conversely, the smaller the rhonchi, the more numerous they are in the same place. A change in the caliber of rhonchi is also accompanied by a change in the pitch of the sound. Small rhonchi have a higher pitch than large ones. In tuberculous pneumonic infiltration of lung tissue, one can trace how the quantity and quality of rhonchi change over weeks and months. At first, small-bubble rhonchi are heard, sometimes of a crepitant nature, then as the process develops, the rhonchi become larger, and with the formation of a cavity, they acquire a resonant character. A similar evolution of rhonchi can be observed in lobar pneumonia over several days (see Pneumonia). It should also be noted that in the initial period of tuberculous infiltration, auscultatory phenomena are determined earlier than percussion findings, and a characteristic property of rhonchi is their persistence with which they are always found in the same place. When such auscultatory phenomena are localized in the lower lobe, chronic pneumonia or bronchiectasis should be suspected. In the presence of a cavity with smooth walls, resonant rhonchi acquire a metallic tint. Very rarely in pyopneumothorax or a large cavity, the sound of a falling drop-gutta cadens can be heard. This phenomenon is obtained with a dense exudate when the patient is turned. Settling on irregularities, strands covering the pleura, the fluid falls in drops onto the horizontal level of the exudate and causes this rare phenomenon. If the strands running in the pneumothorax cavity are fused with the pericardium, then the tension of the strand with each heartbeat in the air cavity is sometimes accompanied by the appearance of a metallic-sounding tone of a taut string. With a certain tension of the air bubble in left-sided artificial pneumothorax, the heart tones also acquire a metallic character. In left-sided tuberculous processes, small disintegrating foci are often located in the lingula of the lung, covering the heart. With adhesions to the pericardium, an increase in rhonchi can be detected with each heartbeat. These rhonchi are heard outside the respiratory phase. In the intercostal space on the left, a fine, pleuro-pericardial friction noise resembling crepitation can sometimes be heard. When listening to the a. pulmonalis, this scraping sound is difficult to distinguish from a systolic murmur, but its intensification during exhalation and the presence of tender points suggest limited pleural involvement. Such limited dry pleurisy in young people in most cases has a tuberculous etiology. The only rhonchi occurring in lung tissue are crepitation (see). These rhonchi in the lung parenchyma are sometimes very difficult to distinguish from the sound of pleural friction. Differentiation is usually carried out according to the following signs: 1) when pressing with the stethoscope, the sound of pleural friction intensifies; 2) when coughing, the sound of friction does not change, while rhonchi change-they disappear or intensify; 3) the sound of pleural friction is heard during both respiratory phases with equal intensity; 4) typical for the sound of friction is the intensity of the noise, increasing toward the end of exhalation. Depending on the nature of changes in the pleura, the most diverse shades are found in the sound of friction-from rough, resembling skin friction, to the gentle rustling of silk. The latter sound impression resembles crepitant, or small-bubble, rhonchi. Neumann calls such a sound pleural rhonchi. In places remote from the hilus, the sound of pleural friction is heard especially distinctly. This is explained by the large amplitude of lung movement in these areas. Over cavities, the sound of pleural friction acquires a resonant, sometimes metallic character.