AUSCULTATION in the early stage re veals diminished breath-sounds, and very shortly the crepitant rale is to be de tected, especially at the termination of a full inspiration. In addition to this sig nificant rale various riles, some coarse, some fine, moist as well as dry, are to be heard over both lungs; these sounds are evidences of the acute bronchial catarrh which so frequently accompanies pneu monia.
When solidification of the exudate oc curs the crepitant rale disappears and the breath-sounds become bronchial. Should the main bronchus leading to the con solidated area be obstructed with mucus, however, bronchial breathing as well as riles may be absent. Over the consoli dated area the voice-sounds assume those peculiarities known as bronchophony. This may be modified to the extent that the voice-sounds possess the bleating and nasal qualities termed regophony. Dur ing the stage of consolidation numerous bronchial riles, both dry and moist, are usually to be detected. As the exudation
undergoes liquefaction with the occur rence of resolution numerous moist riles of marked intensity are to be heard. Bronchial breathing and bronchophony become less and less distinct; and the crepitant rale, somewhat coarser in char acter than that which has accompanied the stage of congestion, is again to be heard: the crepitus redux. This, how ever-, does not occur in all cases.
Over the unaffected portion of the in volved lung, as well as over the unaffected lung, the breath-sounds remain vesicular, but intensified, constituting the so-called puerile breathing.
In central pneumonia bronchial breathing and the crepitant rale may not be detected, for the reason that these sounds are muffled by the surrounding healthy lung.