A ventilator (6) intended to be connected to a patient (4) for breathing therapy comprising a control unit (28) comprising an input for receiving EMG signals from an EMG detector (34) and an output for an EMG based control signal and a pneumatic unit (10) for generating breathing gas flows in dependence of the EMG based control signal is described. Its function is ensured in a better way in that the ventilator (6) comprises a detector (12, 14, 22, 24) for determining a parameter related to breathing dynamics for the patient (4), said detector (12, 14, 22, 24) being connected to the control unit (28), wherein said control unit (28) is arranged to control the pneumatic unit (10) in dependence of the parameter related to breathing dynamics in the case of loss of EMG signals on the input.