l8o PATHOLOGICAL RESPIRATORY SOUNDS. 



of the chest, the vesicular sound obscures the tubular or bronchial sound. If the 

 air-vesicles are deprived of their air, the tubular breathing becomes distinct. 



Bronchial respiration is produced chiefly in the larynx, owing to the formation of 

 air-eddies in consequence of the narrowing of the respiratory part of the glottis. 

 This " laryngeal stenosis sound " excites resonance of the tracheo-bronchial column of 

 air, and communicates to it the specific character of bronchial breathing which is 

 heard over the large tubes of the bronchial system (Dehio). 



It is asserted that, when lungs containing air are placed over the trachea, the tubular sound 

 there produced becomes vesicular. In this case, we must suppose that the vesicular sound 

 arises from the tubular breathing becoming weakened, and acoustically altered by being 

 conducted through the lung alveoli. A sighing sound is often produced at the apertures of 

 the nose and mouth during forced inspiration. 



117. PATHOLOGICAL RESPIRATORY SOUNDS. [The breath-sounds heard in disease may 

 be merely modifications of the normal vesicular or bronchial sounds, or new sounds, such as 

 friction sounds, rales, or rhonchi.] 



[Puerile Breathing is merely an exaggerated vesicular sound, so called because it resembles 

 the louder vesicular sound heard in children. It occurs when some part of the lung is unable to 

 act, and there is, as it were, extra work of the other parts to compensate, and thus the sound is 

 exaggerated.] 



(1) Bronchial or Tubular Breathing occurs over the entire area of the lung, either when the 

 air- vesicles are devoid of air, which may be caused by the exudation of fluid or solid constituents, 

 or when the lungs are compressed from without. In both cases vesicular sounds disappear, and 

 the condensed or solidified lung-tissue conducts the tubular sound of the large bronchi to the 

 surface of the chest. [The sound heard over a hepatised lobe of the lung in pneumonia is a 

 typical example.] It also occurs in large cavities, with resistent walls near the surface of the 

 lung, provided these cavities communicate with a large bronchus. [In this case it is termed 

 cavernous breathing.] 



(2) The amphoric sound is compared to that produced by blowing over the mouth of an 

 empty bottle. It occurs either when a cavity at least the size of the fist exists in the lung, 

 which is so blown into during respiration that a peculiar amphoric-like sound, with a metallic 

 timbre, called metallic tinkling, is produced ; or when the lung still contains air, and is capable 

 of expansion ; as there is still air in the pleural cavity, it acts as a resonator, and causes an 

 amphoric sound, simultaneous with the change of air in the lungs. [The amphoric sound or 

 echo and metallic tinkling are the only certain signs of the existence of a cavity in the lung.] 



(3) If obstruction occurs in the course of the air-passages of the lungs, various results may 

 accrue, according to the nature of the resistance :- (a) owing to various causes, e.g., in the 

 apices of the lungs, there may be partial swelling of the walls of the air-tubes, or infiltration 

 into the air-cells which hinders the regular supply of air. In these cases, parts of the lung 

 are not supplied with air continuously ; it only reaches them periodically, when a cogwheel 

 sound occurs. A similar sound may be heard occasionally in a normal lung, when the 

 muscles of the chest contract in a periodic spasmodic manner, (b) When the air entering large 

 bronchi causes the formation of bubbles in the mucus which may have accumulated there, 

 " mucous rales " are produced. They also occur in small spaces when the walls are separated 

 from their fluid contents by the air entering during inspiration, or when the walls, being adherent 

 to each other, are suddenly pulled asunder. The rales are distinguished as moist (when the 

 contents are fluid), or as dry (when the contents are sticky) ; they may be inspiratory, expiratory, 

 or continuous, or they may be coarse or fine ; further, there is the very fine crepitation, or 

 crackling sound, and, lastly, the metallic tinkling caused in large cavities through resonance. 

 [Crepitation or vesicular rales are fine crepitating sounds like those produced by rubbing a lock 

 of hair between the fingers near one's ear ; they occur only during inspiration, and are a proof that 

 some air is entering the air-vesicles. It is heard in its typical form during the first stage of 

 pneumonia, and seems to be produced by the bursting of minute bubbles of air in a fluid.] (c) 

 When the mucous membrane of the bronchi is greatly swollen, or is so covered with viscid 

 mucus that the air must force its way through, deep sonorous rhonchi (rhonchi sonori) may 

 occur in the large air-passages, and clear shrill sibilant sounds (rhonchi sibilantes) in the smaller 

 ones. [Rhonchi are usually due to catarrh or to affections of the bronchial mucous membrane 

 or bronchitis.] When there is extensive bronchial catarrh, not unfrequently we feel the chest- 

 wall vibrating with the rale sounds (bronchial fremitus). 



(4) If fluid and air occur together in one pleural cavity in which the lung is collapsed, on 

 shaking the person's thorax vigorously we hear a sound such as is produced when air and 

 water are shaken together in a bottle. This is the succussion sound of Hippocrates. Much 

 more rarely this sound is heard under similar conditions in large pulmonary cavities. 



(5) Pleural Friction. When the two opposed surfaces of the pleura are inflamed, have 

 become soft, and are covered with exudation, they move over each other during respiration, and 



