A ventilatory system which may be operated in an invasive and a non-invasive mode is provided utilizing a graphical user interface for presenting only those controlled parameters utilized for that specific mode of operation. Volume and pressure ventilatory support parameters are included for invasive ventilation and non-invasive ventilation control parameters are provided for non-invasive ventilatory assistance. The graphical user interface enables an operator to select the desired mode of operation wherein only those parameters related to that specific mode of operation are presented. Furthermore, a blower is provided for providing an air source to the ventilator enabling the ventilator to be self sufficient.