Compressed air control device for a CPAP device having: a pressure ascertaining device for ascertaining a pressure curve of the pressure in a hollow body of the CPAP device and for generating a corresponding pressure signal, a pressure curve-evaluating means (103, 104, 105) for evaluating the ascertained pressure curve of the pressure in accordance with at least one predetermined criterion and for generating a pressure modulation control signal based upon the result of the evaluation, and a pressure modulation device for receiving an essentially constant compressed air flow and for outputting a modulated compressed air flow to the CPAP device, said pressure modulation device being embodied in such a manner that it modulates in response to the pressure modulation control signal a pressure of the compressed air flow that is output to the CPAP device, characterized in that the pressure curve-evaluating means (103, 104, 105) is embodied in such a manner that during the evaluation procedure an apnoea phase is ascertained and in response to ascertaining said apnoea phase in this manner a pressure modulation control signal is output so as to trigger a pressure pulse in the modulated compressed air flow to the pressure modulation device, the pressure curve-evaluating means (103, 104, 105) for identifying an apnoea phase ascertains whether the pressure is essentially constant over a predetermined time period, wherein the predetermined time period is preferably in the region of 2 to 5 seconds, and the pressure curve-evaluating means (103, 104, 105) is embodied in such a manner that during the evaluation procedure it ascertains natural breathing reflexes and in response to ascertaining said breathing reflexes in this manner outputs a pressure modulation control signal so as to trigger a pressure pulse (12, 13) in the modulated compressed air flow to the pressure modulation control device, said pulse being correlated and synchronised with the natural breathing reflex. a pressure ascertaining device for ascertaining a pressure curve of the pressure in a hollow body of the CPAP device and for generating a corresponding pressure signal, a pressure curve-evaluating means (103, 104, 105) for evaluating the ascertained pressure curve of the pressure in accordance with at least one predetermined criterion and for generating a pressure modulation control signal based upon the result of the evaluation, and a pressure modulation device for receiving an essentially constant compressed air flow and for outputting a modulated compressed air flow to the CPAP device, said pressure modulation device being embodied in such a manner that it modulates in response to the pressure modulation control signal a pressure of the compressed air flow that is output to the CPAP device, characterized in that the pressure curve-evaluating means (103, 104, 105) is embodied in such a manner that during the evaluation procedure an apnoea phase is ascertained and in response to ascertaining said apnoea phase in this manner a pressure modulation control signal is output so as to trigger a pressure pulse in the modulated compressed air flow to the pressure modulation device, the pressure curve-evaluating means (103, 104, 105) for identifying an apnoea phase ascertains whether the pressure is essentially constant over a predetermined time period, wherein the predetermined time period is preferably in the region of 2 to 5 seconds, and the pressure curve-evaluating means (103, 104, 105) is embodied in such a manner that during the evaluation procedure it ascertains natural breathing reflexes and in response to ascertaining said breathing reflexes in this manner outputs a pressure modulation control signal so as to trigger a pressure pulse (12, 13) in the modulated compressed air flow to the pressure modulation control device, said pulse being correlated and synchronised with the natural breathing reflex.