A system (1) for ventilating patients includes a gas passage unit (2), which has a first inlet opening (6) with a fluid-communicating connection to a pressurized gas source (12, 13) and an outlet opening (9) connected to the first inlet opening (6) in a manner. A patient interface (3), for ventilation, includes an interface inlet opening (10). A gas line element (4) has a fluid-communicating connection to the outlet opening (9) and to the interface inlet opening (10). A controllable pressure change element (5) is provided between the first inlet opening (6) and the interface inlet opening (10). A second inlet opening (8) has a fluid-communicating connection to the gas line element (4). A control unit (7) controls the controllable pressure change element (5). A device or a system (1), which provides fully adequate ventilation with high performance with minimal expenditure for hardware, is provided.
