480 



OPERATIONS ON THE RESPIEATOEY APPARATUS. 



Fig. 421.— Ordinary Tracheotomy Tube, front and back view. 



slit at each corner, for the attachment of bands or straps. These 

 tubes are generally made of silver or nickel-plated metal, though 

 gutta percha is the material sometimes used, its lack of sohdity, 

 however, rendering the instruments composed of it uncertain and 

 dangerous. Besides this ordinary tube, there is a long catalogue 

 of others, among which we have those invented by Dieterichs, 

 Gowiug, Spooner, Vachette, Pradat, Brogniez, Leblanc, Eenault, 

 Peuch, Imlin, Trasbot, and these do not exhaust the list. But 

 among all this host of instruments of this class there is probably 

 none which fulfils its purpose better than that of Director Degives, 

 somewhat modified by Professor Peuch (Pig. 430), which, by its 

 simpUcity, and especially from the fact of its being a self-holder, 

 has proved itself to be the most convenient of all for general prac- 

 tice. When once inserted and adjusted, this tube may be left in 

 place without danger of removal or dropping of itself, while the or- 

 dinary tube, which requires to be secured by strings tied over the 

 neck, can never be as safe as the self-retaining instruments, which 

 hold themselves. 



There are two methods of performing the operation, one of which 

 may be called the classical, and the other the immediate method. 

 In the former, two adjoiniug tracheal rings are divided, and re- 

 moved, in part or totally ; ia the latter, a longitudinal incision is 

 jnade through the rings without loss of substance (Pig. 433). In 



