A tracheostomy tube assembly has a flange arrangement (2) movable along the shaft (1) of the assembly and lockable at different positions. The flange arrangement has a gel-filled member (22) with a flexible conformable surface (26) providing substantially the entire surface contacting the skin. The flange has aperture (28) through which a tape can be extended for use in securing the assembly with the patients neck. The gel-filled member (122) may be provided separately for use on existing tube assemblies.
