282 BEOXCIIITIS. 



BRONCHITIS. 



This may be produced by several causes, sucb as sudden clianges of 

 temperature from hot to cold, and vice versa. Excitement as a result of 

 over-exertion "will sometimes cause it, but it is not generally a primary 

 disease. That inflammation of the superior respiratory passages, con- 

 stituting catarrh, gradually creeps downwards and involves the larynx 

 and the trachea, and at length, possibly, the farthest and the minutest 

 ramifications of the air-tubes. When it is found to be thus advancing its 

 progress should be carefully watched by the assistance of auscultation. 

 The distant murmur of the healthy lung cannot be mistaken, nor the cre- 

 pitating sound of pneumonia; and in bronchitis the blood may be heard 

 filtering or breaking through the divisions of the lobuli, and accounting 

 for that congestion or filliug of the cells with mucus and blood, which is 

 found after intense inflammation. Inflammation precedes this increased 

 discharge of mucus. Even that may be detected. The inflamed mem- 

 brane is thickened and tense. It assumes an almost cartilaginous struc- 

 ture, and the murmur is not only louder, but has a kind of snoring sound. 

 Some have imagined that a sound like a metallic ring is mingled with it ; 

 but this is never very distinct. 



The interrupted whizzing sound has often and clearly Indicated a case 

 of bronchitis, and there are many corroborative symptoms which should be 

 regarded. The variable temperatnre of the extremities "will be an important 

 guide — not intensely cold as in pneumonia, nor of increased temperature as 

 often iu catarrh, but with a tendency to coldness, yet this varj-ing "much. 

 The pulse will assist the diagnosis. It will be quick, but feeble, from 70 

 to 80 per minute, — more rapid than in catarrh, much more so than in the 

 early stage of pneumonia ; not so hard as in pleui-isy, more so than in 

 catarrh, and not oppressed as in pneumonia. The respiration should next 

 be examined, abundantly raore rapid than in catarrh, pneumonia, or 

 pleurisy ; geaerally as rapid and often more so than the pulse, and accom- 

 panied by a wheezing sound, heard at some distance. Mr. Percivall 

 relates a case in which the respiration was more than one hundi'ed in a 

 minute. Mr. C. Percivall describes an interesting case in which the re- 

 spii'ation "was quick in the extreme ; and he remarks, that he does ' not 

 remember to have seen a horse "with his respu^ation so disturbed.' 



In addition to these clearly characteristic symptoms, will be observed a 

 haggard countenance, to which the anxious look of the horse labouring 

 under inflammation of the lungs cannot for a moment be compared ; also 

 an evident dread of sufibcation, expressed, not by inability to move, as in 

 pneumonia, but frequently an obstiuate refusal to do so ; cough painful in 

 the extreme ; breath hot, yet no marked pain in the part, and no looking 

 at the side or flanks. 



As the disease proceeds there will be a short, frequent, pectoral cough, 

 with considerable discharge from the nostrils, much more than in catarrh, 

 because greater extent of membrane is afiected. It will be muco-purulent 

 at first, but "\\all soon become amber-coloured or gTeen, or greyish green ; 

 and that not from any portion of the food being returned, but from the 

 peculiar hue of the secretion from ulcers in the bronchial passages. Small 

 organised portions Avill mingle "with the discharge, — shreds of mucus con- 

 densed and hardened, and forced from the inside of the tube. If the 

 disease proceeds, the discharge becomes bloody, and then, and sometimes 

 earlier, it is foetid. 



The termination of this disease, if unchecked, is frequently pneu- 

 monia. Although we cannot trace the air-tubes to theii" termination, 

 the inflammation will penetrate into the lobuli, and afi"ect the 



