(pneumosclerosis) after acute or chronic inflammatory processes, such as acute lobar pneumonia (with subsequent carnification of the lung), lung infarction, pulmonary abscess, tuberculosis, etc.; (3) resection of a part or the entire lung; (4) atelectasis (collapse of the lung or its portion) that may occur due to closure of the lumen in a large bronchus by a foreign body or a tumour growing into the lumen of the bronchus and causing its obturation. The closure of the air passage into the lung with subsequent resorption of air from the alveoli and a decrease in the volume of the lung diminish the corresponding half of the chest. The chest thus becomes asymmetrical, the shoulder of the affected side lowers, the clavicle and the scapula lower as well, and their movements during deep respiration become slower and limited; the supra-and subclavicular fossae become more depressed, the intercostal spaces decrease in size or become invisible. The marked depression of the supraclavicular fossa on one side often depends on the diminution of the apex of a fibrosis-affected lung.
Dynamic survey of the chest
Respiratory movements of the chest should be examined during dynamic survey of the chest. In physiological conditions they are performed by the contraction of the main respiratory muscles: intercostal muscles, muscles of the diaphragm, and partly the abdominal wall muscles. The socalled accessory respiratory muscles (mm. sternocleidomastoideus, trapezius, pectoralis major et minor, etc.) are actively involved in the respiratory movements in pathological conditions associated with difficult breathing.
The type, frequency, depth and rhythm of respiration can be determined by carefully observing the chest and the abdomen.
Respiration can be costal (thoracic), abdominal, or mixed type. Thoracic (costal) respiration. Respiratory movements are carried out
mainly by the contraction of the intercostal muscles. The chest markedly broadens and slightly rises during inspiration, while during expiration it narrows and slightly lowers. This type of breathing is known as costal and is mostly characteristic of women.
Abdominal respiration. Breathing is mainly accomplished by the diaphragmatic muscles; during the inspiration phase the diaphragm contracts and lowers to increase rarefaction in the chest and to suck in air into the lungs. The intraabdominal pressure increases accordingly to displace of the abdominal wall. During expiration the muscles are relaxed, the diaphragm rises, and the abdominal wall returns to the initial position. This type of respiration is also called diaphragmatic and is mostly characteristic of men.
Mixed respiration. The respiratory movements are carried out simultaneously by the diaphragm and the intercostal muscles. In
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physiological conditions this respiration sometimes occurs in aged persons and in some pathological conditions of the respiratory apparatus and the abdominal viscera. For example, in women with dry pleurisy, pleural adhesion, myositis, and thoracic radiculitis, the contractile activity of the intercostal muscles decreases and the respiratory movements are carried out by the accessory movements of the diaphragm. In extensive pleural adhesion, lung emphysema, and in strong pain in the chest due to acute inflammation of the intercostal muscles or nerves, respiration is temporarily carried out by the diaphragmatic muscles exclusively. Mixed respiration occurs in men with underdeveloped diaphragmatic muscles, in diaphragmatitis, acute cholecystitis, perforating ulcer of the stomach or the duodenum. Respiration in such cases is sometimes carried out only by the intercostal muscles.
Respiration rate. Respiration rate can be determined by counting the movements of the chest or the abdominal wall, with the patient being unaware of the procedure. The pulse rate should first be taken and then the respiration rate. The number of respiratory movements in a healthy adult at rest should be 16 to 20 per minute, in the newborn 40-45, this rate gradually decreasing with age. The respiration rate decreases during sleep to 12—14 per minute, while under physical load, emotional excitement, or after heavy meals the respiration rate increases.
The respiration rate alters markedly in some pathological conditions. The causes of accelerated respiration may be (1) narrowing of the lumen of small bronchi due to spasms or diffuse inflammation of their mucosa (bronchiolitis occurring mostly in children), which interfere with normal passage of air into the alveoli; (2) decreased respiratory surface of the lungs due to their inflammation and tuberculosis, in collapse or atelectasis of the lung due to its compression (pleurisy with effusion, hydrothorax, pneumothorax, tumour of mediastinum), in obturation or compression of the main bronchus by a tumour, in thrombosis or embolism of the pulmonary artery, in pronounced emphysema, when the lung is overfilled with blood or in a case of lung edema in certain cardiovascular diseases; (3) insufficient depth of breathing (superficial respiration) which can be due to difficult contractions of the intercostal muscles or the diaphragm in acute pain (dry pleurisy, acute myositis, intercostal neuralgia, rib fracture, or tumour metastasis into the ribs), in a sharp increase in the intra-abdominal pressure and high diaphragm (ascites, meteorism, late pregnancy), and finally in hysteria.
Pathological deceleration of respiration occurs in functional inhibition of the respiratory centre and its decreased excitability. It can be due to increased intracranial pressure in patients with cerebral tumour, meningitis, cerebral hemorrhage, or edema of the brain, and also due to the toxic effect on the respiratory centre when toxic substances are
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accumulated in the blood, e.g. in uremia, hepatic or diabetic coma, and in certain acute infectious diseases.
Respiration depth. The depth of breathing is determined by the volume of the inhaled and exhaled air at rest. This volume varies in an adult from 300 to 900 ml (500 ml on the average). Depending on depth, breathing can be either deep or superficial. Superficial (shallow) breathing often occurs in pathologically accelerated respiration when the length of the inspiration and the expiration phases becomes short. Deep breathing is, on the contrary, associated in most cases with pathological deceleration of the respiration rate.
Deep and slow respiration, with marked respiratory movements, is sometimes attended by noisy sounds. This is Kussmaul's respiration occurring in deep coma accompanied by decompensated acidosis (diabetic hyperglycemic-hyperketonemic coma, uremic coma). In some pathological conditions, however, rare respiration can be shallow, while accelerated breathing deep. Rare superficial respiration can occur in sharp inhibition of the respiratory centre, pronounced lung emphysema, and sharp narrowing of the vocal slit or the trachea. Respiration becomes accelerated and deep in high fever and marked anemia.
Respiration rhythm. Respiration of a healthy person is rhythmic, of uniform depth and equal length of the inspiration and expiration phases. Rhythm of the respiratory centre can be inhibited in some types of cerebral edema. Derangement of the respiratory function can cause disorders in which a series of respiratory movements alternates with a pronounced (readily detectable) elongation of the respiratory pause (lasting from a few seconds to a minute) or a temporary arrest of respiration (apnea). This respiration is known as periodic respiration.
Biot's respiration is characterized by rhythmic but deep respiratory movements which alternate (in approximately regular intervals) with long respiratory pauses (from few seconds to half a minute). Biot's respiration occurs in meningitis patients and in agony with disorders of cerebral circulation.
Cheyne-Stokes respiration is characterized by periods (from few seconds to a minute) of cessation of respiration, followed by noiseless shallow respiration, which quickly deepens, becomes noisy to attain its maximum at the 5-7th inhalation, and then gradually slows down to end with a new short respiratory pause. During such pauses, the patient often loses his sense of orientation in the surroundings or even faints, to recover from the unconscious condition after respiratory movements are restored. This respiratory disorder occurs in diseases causing acute or chronic insufficiency of cerebral circulation and brain hypoxia, and also in heavy poisoning. More frequently this condition develops during sleep and is more characteristic of aged persons with marked atherosclerosis of the cerebral
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arteries.
Undulant (wave-like) Grocco's respiration somewhat resembles Cheyne-Stokes respiration except that a weak shallow respiration occurs instead of the respiratory pause with subsequent deepening of the respiratory movement, followed by slowing down. This type of arrhythmic dyspnea can probably be regarded as the early stages of the same pathological processes which responsible for Cheyne-Stokes respiration.
Palpation of the chest
Palpation is used as an additional means of examination to verify findings of observation (the shape of the chest, its dimensions, respiratory movements), for determining local or profuse tenderness of the chest, its elasticity (resistance), vocal fremitus, pleural friction and sounds of fluid in the pleural cavity.
Palpation should be done by placing the palms on the symmetrical (left and right) parts of the chest. This examination helps follow the respiratory excursions and deviation of the chest movements from their normal course. The epigastric angle is determined by palpation as well. The thumbs should be pressed tightly against the costal arch, their tips resting against the xiphoid process.
Palpation is used to locate pain in the chest and its irradiation. For example, in rib fracture, pain is localized over a limited site, namely at the point of the fracture. Displacement (careful) of bone fractures will be attended in this case by a specific sound (crunch). Inflammation of the intercostal nerves and muscles also causes pain, but it can be felt during palpation over the entire intercostal space. Such pain is called superficial. It is intensified during deep breathing, when the patient bends to the affected side, or lies on this side.
Resistance (elasticity) of the chest is determined by exerting pressure of the examining hands from the front to the sides of the chest or on the back and the sternum, and also by palpation of the intercostal spaces. The chest of a healthy person is elastic. The chest of a healthy person may be compressed on 2-3 cm under the moderate pressure in both the anteroposterior and lateral directions. In the presence of pleurisy with effusion, or pleural tumour, the intercostal space over the affected site becomes rigid. Rigidity of the chest increases in general in the aged due to ossification of the costal cartilages, development of the lung emphysema, and also with filling of both pleural cavities with fluid. Increased resistance of the chest can be felt during examining the chest by compression in both the anteroposterior and lateral directions.
Palpation is used for determining the strength of voice conduction to the chest surface (fremitus vocalis s. pectoralis). The palms of the hands are placed on the symmetrical parts of the chest and the patient is asked to utter
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loudly a few words (with the letter 'r' in them to intensify vibration). The voice should be as low as possible since voice vibrations are better transmitted by the air column in the trachea and the bronchi to the chest wall in this case. Fremitus vocalis can also be determined by one hand as well: the palm of the examining hand should be placed alternately on the symmetrical parts of the chest. Fremitus vocalis is not determined at the region of the heart below the third rib on left parasternal and midclavicular lines.
Vocal fremitus is of about the same intensity in the symmetrical parts of the chest of a healthy person. Vocal vibrations are louder in the upper parts of the chest and softer in its lower parts. Moreover, voice conduction is better in men with low voice and thin chest; the vibrations are weaker in women and children with higher voice (and also in persons with the well developed subcutaneous fat tissues). Vocal fremitus can be stronger or weaker (or in some cases it can even be impalpable) in pathological conditions of the respiratory organs. In focal affections, vocal fremitus becomes unequal over symmetrical parts of the chest.
Vocal fremitus is intensified when a part of the lung or its whole lobe becomes airless and more uniform (dense) because of a pathological process. According to the laws of physics, dense and uniform bodies conduct sound better than loose and non-uniform. Induration (consolidation) can be due to various causes, such as acute lobar pneumonia, pulmonary infarction, tuberculosis, accumulation of air or fluid in the pleural cavity, etc. Vocal fremitus is also intensified in the presence in the pulmonary tissue of an air cavity communicated with the bronchus.
Vocal fremitusbecomes weaker (1) when liquid or gas are accumulated in the pleural cavity; they separate the lung from the chest wall to absorb voice vibrations propagating from the vocal slit along the bronchial tree; (2) in complete obstruction of the bronchial lumen by a tumour which interferes with normal conduction of sound waves to the chest wall; (3) in asthenic emaciated patients (with weak voice); (4) in significant thickening of the chest wall in obesity.
Low-frequency vibrations due to pleural friction (friction fremitus) in dry pleurisy, crepitation sounds characteristic of subcutaneous emphysema of the lungs, vibration of the chest in dry, low (low-pitch buzzing) rales can also be determined by palpation.
Percussion of lungs
Percussion
Percussion (L percutere to strike through) was first proposed by an Austrian physician Auenbrugger in 1761. Tapping various parts of the human body produces sounds by which one can learn about the condition of
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