DISEASES OF THE LARYNX. 141 



run a very rapid course. It has also been met with as 

 the result of the inhalation of poisonous acrid vapours 

 and hot air. Sometimes, in a few hours, the swelling and 

 infiltration become very considerable and the breathing 

 much disturbed. The pulse is accelerated, the temperature 

 elevated, and the visible mucous membranes become of a 

 purplish hue, owing to deficient aeration of the blood. The 

 nose is protruded, the superior air-passages being thus 

 made to approach as near as possible a horizontal line. 

 The glottis is indeed sometimes so occluded through exces- 

 sive infiltration of the structures bounding the orifice as to 

 cause imminent danger to life from suffocation. 



Rapid eff'usion into the submucous tissue and swelling 

 of the mucous membrane is termed ' oedema glottidis.' 

 In these cases the respiration becomes suddenly difficult, 

 and the inspiratory act is especially prolonged, and accom- 

 panied with a peculiar harsh sound succeeded by a short 

 expiration. The alae of the nostrils are dilated to their 

 full extent, the face has an anxious expression, and there is 

 great distress. The extremities are cold, and sweats bedew 

 the body. The animal stamps with its feet, and the distress 

 becomes increased ; the visible mucous membranes become 

 more livid, prostration ensues, and the horse, unless relieved, 

 soon succumbs. 



Sequelae of Laryngitis. — Thickening of the mucous 

 membrane ; atrojDhy and degeneration of the laryngeal 

 muscles -, and ulceration of the structures bounding the 

 rima glottidis. 



Treatment of Laryngitis. — In severe cases the treatment 

 should be as prompt as possible. Inhalations of hot- water 

 vapour, medicated or not, and hot fomentations should be 

 applied, but if the general distress and difiiculty in breath 

 ing continue, tracheotomy may be necessary in order to 

 avert suffocation. The hot-water vapour may be generated 



