Source:http://linkedlifedata.com/resource/umls/id/C3203826
UMD: Tubes designed for insertion into an opening (i.e., stoma) performed in the neck and trachea (windpipe) to keep it open, facilitating breathing. Most of these devices (i.e., double-cannula tubes) consist of the following: (1) an external metallic or, more frequently, plastic or silicone curved tube (outer cannula) that fits directly into the tracheal stoma with a proximal flange (neck plate) designed to accommodate mechanisms for securing the tube (e.g., an external tracheostomy holder); (2) an obturator inserted into the outer cannula to guide the external tube during insertion into the trachea that is immediately removed after the outer cannula is in proper position; and (3) an internal cannula (including a lock to prevent it from being coughed out) that is inserted through the external tube after the obturator is removed. This cannula may have an adapter for use with ventilatory equipment. Some simpler and smaller devices (single-cannula tubes) used mainly in children do not include an internal cannul