STENOSIS OF THE TRACHEA. 
191 
The course of the disease depends on the extent of the injuries and of 
the resulting bleeding. The animal may be completely restored to use¬ 
fulness, or difficulty in breathing may remain (asthma tracheale). The 
dyspnoea depends partly on the degree of stenosis, partly on the character 
of work performed. In spite of marked deformity, dyspnoea may be 
absent, whilst apparently unimportant changes sometimes produce 
greatly disturbed respiration ; indeed, Schwanefeld’s case shows that 
they may cause death. These diversities are explained by the fact that 
the respiratory difficulty is determined, not by the external deformity of 
the trachea, but by the degree of stenosis. The gravity of such cases is 
gauged by the state of the respiration during severe work. In stenosis 
of the upper portions of the trachea, tracheotomy usually affords relief, 
but is not available when the lower portions in the neck or thoracic 
cavity are affected. Such conditions, however, are often aggravated by 
lapse of time. 
Treatment. Where great dyspnoea follows fresh injuries of the tiacliea, 
tracheotomy not only removes the threatened danger of suffocation, but, 
if a tampon-canula is used, also prevents the entrance of blood into the 
trachea. A tampon-canula may be extemporised by carefully wrapping 
the stem of a Barthelemy’s tracheal tube with cloth, but care must be 
taken that the bandage material, tow, wadding, or piece of sponge used 
for this purpose does not fall into the trachea. Severe emphy¬ 
sema, although seldom endangering life, may sometimes necessitate 
tracheotomy. 
Stenoses of the trachea are only occasional reasons for direct treatment. 
In man it is possible to dilate the trachea with elastic tubes introduced 
from the larynx. In animals the use of tubes is more difficult, the time 
for tardy healing would be grudged, while frequently the cicatrices, as 
well as portions of the tracheal rings, are ossified. The position and 
extent of the stenosis must determine whether tracheotomy is applicable, 
or likely to be successful. It is generally serviceable when carried out 
below the stenosed spot. Richolson, by removing a dislocated portion 
of cartilage, permanently relieved the dyspnoea, Similar cases are rare. 
The interesting communication of Lalosse and Stickei show that 
“ tubage ” of the trachea is possible, and may be successful. Lafosse 
divided the trachea below the narrow point caused by tiaclieotomy, 
thrust a cork cylinder, bound round with tow, into the trachea, and fixed 
it with tape. In ten days the cylinder was replaced by a tube, the latter 
was removed after six weeks, the trachea being then so fai dilated as to 
admit of easy respiration without a canula. Sticker dilated the tiacliea 
and larynx by means of a metallic spiral, which was left permanently in 
position, and is said to have finally been covered by the tissues. 
