Special report on diseases of the horse / by Drs. Pearson [and others].

Date:
1903
Catalogue details

Licence: In copyright

Credit: Special report on diseases of the horse / by Drs. Pearson [and others]. Source: Wellcome Collection.

    26/690 (page 20)
    painful, as a rule, in the chronic diseases of the respiratory tract. The force of the cough is considerable when it is not especially pain- ful and when the lungs are not seriously involved. When the lungs are so diseased that they can not be filled with a large volume of air, and in heaves, the cough is weak, as it is also in weak, debilitated animals. If mucus or pus is coughed out, or if the cough is accom- panied by a gurgling sound, it is said to be moist; it is diy when these characteristics are not present—that is, wThen the air in passing out passes over surface not loaded with secretion. In the examination of the chest we resort to percussion and aus- cultation. When a cask or other structure containing air is tapped upon, or percussed, a hollow sound is given forth. If the cask con- tains fluid, the sound is of a dull and of quite a different character. Similarly, the amount of air contained in the lungs can be estimated by tapping upon, or percussing, the walls of the chest. Percussion is practiced with the fingers alone or with the aid of a special percussion hammer and an object to strike upon known as a pleximeter. If the fingers are used, the middle finger of the left, hand should be pressed firmly against the side of the horse and should be struck with the ends of the fingers of the right hand bent at a right angle so as to form a hammer. The percussion hammer sold by instrument makers is made of rubber or has a rubber tip, so that when the pleximeter, which is placed against the side, is struck the impact will not be accompanied by a noise. After experience in this method of exami- nation one can determine with a considerable degree of accuracy whether the lung contains a normal amount of air or not. If, as in pneumonia, air has been displaced by inflammatory product occupy- ing the air space, or if fluid collects in the lower part of the chest, the percussion sound becomes dull. If, as in emphysema or in pneu- mothorax, there is an excess of air in the chest cavity, the percussion sound becomes abnormally loud and clear. Auscultation consists in the examination of the lungs with the ear applied closely to the chest wall. As the air goes in and out of the lungs a certain soft sound is made which can be heard distinctly, especially upon inspiration. This sound is intensified by anything that accelerates the rate of respiration, such as exercise. This soft, rustling sound is known as vesicular murmur, and wherever it is heard it signifies that the lung contains air and is functionally active. The yesicular murmur is weakened when there is an inflammatory infiltration of the lung tissue or when the lungs are compressed by fluid in the chest cavity. The vesicular murmur disappears when air is excluded by the accumulation of inflammatory product, as in pneu- monia, and when the lungs are compressed by fluid in the chest cavity. The vesicular murmur becomes rough and harsh in the early