Abstract: A respiratory device including a breathing gas source assembly, a flow change device, a breathing gas line assembly, a sensor assembly, and a control device with a data memory, the control device being connected for signal transmission to the data memory and to the sensor assembly, the control device being designed, in a normal respiratory operation, not to bring about a machine-triggered breathing stroke starting from a previous breathing stroke before a predetermined normal time interval has elapsed, the control device being further designed to identify, on the basis of data from the sensor assembly, a spontaneous respiratory effort of the patient, the control device being further designed, if it has identified at least a predetermined plurality of spontaneous respiratory efforts of the patient within a predetermined monitoring period, to switch to a challenge respiratory operation, in which, instead of the normal interval, a challenge interval lasting for a longer time is used.

Abstract: A method for determining a respiratory-gas content in a respiratory tract, which content is present in the respiratory tract of an at least partially artificially ventilated patient following a plurality of breaths performed with the involvement of a ventilation apparatus, wherein the plurality of breaths include at least one earlier number of breaths and at least one follow-up breath following the earlier number of breaths; wherein the earlier number of breaths include an earlier breath or a plurality of successive earlier breaths; wherein the method comprises quantitative detection of inspiratory and expiratory respiratory-gas flows by at least one respiratory-gas flow sensor and summation of detected inspiratory and expiratory flow values to form the respiratory-gas content in the respiratory tract; wherein a respiratory tract content starting value, at which the determination of the respiratory-gas content in the respiratory tract for the follow-up breath starts, depending on a difference in respiratory-g