or indirectly with the expansion of the lung, or which diminishes the elasticity of its tissue. Of the first condition we have illustrations in affections which restrain the movements of the thoracic walls, as pleuritic pain, rheumatism, paralysis, etc.; or when there is some obstruction to the entrance of air into the lungs, such as in diseases of the larynx, trachea, or bronchial tubes, or again when a pleuritic effusion or a tumor presses the lungs back from the chest walls, though not to a degree sufficient to prevent all air from entering them. Of the second condition we have examples in pulmonary emphysema, and in incipient tubercular deposits. Absent or Suppressed Respiration occurs whenever, from some cause, the play of the lung is suspended; and this may be either from external pressure, as when the lung is forced against the spinal column by the presence of fluid or air in the pleural cavity; or, on the other hand, when a complete obstruction of the main bronchi prevents the air from either entering or leaving the lungs. Alterations in Mhythni, Interrupted Respiration. — In health the respiratory and expiratory sounds are even and continuous, with a brief interval between each respiratory act; but this may be altered in disease, and both sounds, especially the inspiratory, may have an interrupted or jerking character, termed by some 'cog-wheel respiration.' We have examples of this kind of respiration in asthma, pleurodynia, first stage of pleurisy, and incipient phthisis. It is most frequently associated with tubercle, and may be due probably to some gelatinous mucus adhering to the walls of the finer bronchial tubes, which, though not sufficient to produce rale, still obstructs the free ingress and egress of the air. Prolonged Interval between Inspiration and Expiration.— Instead of these two sounds closely succeeding one another, they may be separated by a distinct interval. When this occurs, either the inspiratory sound is shortened, or the expiratory sound is delayed in its commencement. In the first instance it is the result of pulmonary consolidation, as in tubercle; in the second, the elasticity of the pulmonary tissue is impaired, as in emphysema, no sound being heard during the first portion of the expiratory act. Prolonged Expiration.— Here the ratio between normal inspiration and expiration is inverted. The expiration at times is twice or three times as long as the inspiration. It is always due to a want of freedom in the egress of air from the lungs. The most common, and therefore, practically speaking, the most important cause of prolonged expiration is tubercular deposit in the lung. Excessively prolonged expiration is to be met with in vesicular emphysema, and this is to be distinguished from the prolonged expiration of phthisis by its pitch, which in emphysema is low, lower than the inspiration, while in phthisis it is high, higher than the inspiration, and tubular in quality. Alterations in Quality. Rude Respiration.— This is termed (by Prof. A. Flint) broncho-vesicular respiration. In this variety both inspiratory and expiratory sounds lose their natural softness; the breezy or vesicular quality is lost; the sounds are higher pitched and more tubular in character, while the expiration has more intensity, higher pitch, and longer duration than the inspiration. Rude respiration always indicates more or less consolidation of lung tissue. In normal vesicular respiration, the sounds produced by the vibrations of the air in the air cells and finer bronchi obscure that produced in the trachea and larger bronchial tubes (healthy lung substance being a poor conductor of sound); but so soon as any portion of lung becomes consolidated, the vesicular element of the respiratory sound is diminished and the bronchial element 40 PHYSICAL DIAGNOSIS. becomes prominent; this change constitutes rude respiration. It embraces every degree of modification between complete bronchial respiration on the one hand, and normal vesicular breathing on the other; the increase in bronchial characters corresponding with the degree of consolidation. Rude respiration is of practical value, principally in the diagnosis of incipient phthisis. Bronchial Respiration is characterized by an entire absence of all vesicular quality. The inspiratory sound is high pitched and tubular in character; the two sounds are separated by a brief interval; the expiratory is still higher pitched and more intense than the inspiratory, is as long or longer, and of the same tubular quality. Whenever this modification of the respiratory sound is present, where in health normal vesicular murmur should be heard, consolidation of lung substance may be inferred. Consequently it is an important diagnostic sign in many pulmonary affections such as pneumonia, phthisis pulmonalis, pulmonary apoplexy, etc. Cavernous Respiration.— In some respects this resembles bronchial respiration, and it is often difficult to distinguish one from the other. Some distinguished auscultators declare that this sign does not exist. Its distinguishing characteristics are, on inspiration, a soft, blood-<Callout type="important" title="Critical Diagnostic Sign">Cavernous respiration indicates significant lung pathology such as advanced tuberculosis or pneumothorax.</Callout>ing, low-pitched sound, non-vesicular in character: as a rule, the expiratory sound is lower pitched than the inspiratory, and is always prolonged and puffing. For its production, there must be a cavity of considerable size in the lung substance, having free communication with a bronchial tube. The cavity must be empty and near the surface, its walls must be sufficiently flaccid to expand with inspiration, and collapse with expiration. This sign is most frequently met with in the third stage of phthisis. Amphoric Respiration.— Whenever the respiratory sound has a musical intonation or metallic quality, resembling that produced by blowing gently into the mouth of an empty bottle, it is called amphoric. The amphoric character accompanies both acts of respiration, especially the expiratory. It may be due to tubercular or other excavations in the lung substance, or to an opening from the bronchial tube into the pleural cavity, giving rise to pneumo-thorax. In both cases the sound is produced by vibrations of air in a cavity, which are excited by a current of air from a bronchial tube. The cavity in the lung substance which gives rise to amphoric respiration must be of large size, empty, with tense, firm walls, so as not to collapse with expiration, and it must communicate freely with a large bronchial tube. This sign is mainly of importance in the diagnosis of advanced phthisis and pneumo-thorax. This completes the history of the most important alterations in the natural respiratory sounds produced by disease. With few exceptions they are no new sounds, but are heard in the healthy chest, and become significant of disease only when heard in unnatural locations.
Key Takeaways
- Respiratory sound alterations can indicate various lung diseases such as emphysema, pneumonia, and tuberculosis.
- Different types of respiration like rude, bronchial, cavernous, and amphoric have specific diagnostic significance.
- Understanding the natural respiratory sounds is crucial for identifying pathological changes.
Practical Tips
- Listen carefully to the intervals between inspiration and expiration; alterations can indicate serious conditions.
- Use a stethoscope to detect subtle changes in sound quality that may not be audible otherwise.
- Be aware of the pitch, duration, and character of respiratory sounds for accurate diagnosis.
Warnings & Risks
- Misdiagnosis due to overlooking subtle sound changes can delay necessary treatment.
- Ignoring prolonged expiration or cavernous respiration can lead to untreated severe lung conditions.
- Failure to distinguish between normal and pathological sounds may result in incorrect medical decisions.
Modern Application
While the diagnostic techniques described here are foundational, modern medicine has advanced with imaging technologies like X-rays and CT scans. However, understanding these historical methods remains crucial for interpreting patient symptoms accurately and making informed clinical judgments.
Frequently Asked Questions
Q: What does 'rude respiration' indicate?
Rude respiration indicates more or less consolidation of lung tissue, often associated with early stages of tuberculosis. It is characterized by higher pitched and tubular sounds during both inspiration and expiration.