endotracheal       
adjective  medical specialized uk/ˌen.dəʊ.trəˈkiː.əl/ us/ˌen.doʊˈtreɪ.ki.əl/
 气管内的;经气管腔的
inside or passing through the trachea (= the tube that carries air from the throat to the lungs)
  An anesthesiologist inserts an endotracheal tube into the windpipe. 麻醉师把一条气管内导管插入气管中。