The respiration cannula (1) is sealed externally against an opening after tracheostomy by application of a seal compressed against the patient's neck. The seal is pref. a plate (2) and the compression device is formed by a cushioned plate, which comprises the sealing plate against an opening remaining after tracheostomy such that the cushion abuts the sealing plate. The cannula is inserted via the hole in the sealing plate into the trachea.
