Abstract: An attachment for a tracheal cannula, the attachment surrounding a cavity, the attachment being open both in a coupling area of the attachment as well as in an orifice area of the attachment, differing in location from the coupling area, for providing an access to the cavity, the attachment having in the coupling area a latching formation, which is designed for the releasable connection to a mating latching formation of the tracheal cannula, the coupling area surrounding a section of the cavity, the section of the cavity surrounded by the coupling area being centrally penetrated by a virtual coupling axis, the coupling axis defining an axial direction along its path, defining a plurality of radial directions orthogonally to its path and defining a circumferential direction running around it, the coupling area having at least one support section, on which the latching formation and a force application area are situated in such a way that by exerting an actuating force on the force application area in the radia

Abstract: The invention relates to a patient treatment gas supply system having a nasal cannula having a cannula connection and a treatment gas outlet opening; a treatment gas supply line having a line connection which is designed to form a detachable treatment-gas-carrying connection in a connection region with the cannula connection, wherein the cannula connection and the line connection overlap along a flow path formed via the connection region; and a blocking assembly which can be moved between a blocking position and a release position, wherein a force necessary for releasing the connection between the cannula connection and the line connection is greater when the blocking assembly is in the blocking position than when the blocking assembly is in the release position.