A device for providing ventilatory assist to a patient is disclosed. The device comprises a manifold having an inspiratory port to receive an inspiratory flow from an inspiratory supply line, an interface port connectable to an external end of an endotracheal tube inserted in a patient's trachea and an expiratory port configured to receive an expiratory flow from the endotracheal tube via the interface port. An inspiratory lumen has a distal end insertable in the endotracheal tube. A cross-section of the inspiratory lumen is smaller than that of the endotracheal tube to allow gas flowing in the endotracheal tube. The inspiratory flow is directed to the inspiratory lumen, or to the endotracheal tube, or at once to the inspiratory lumen and to the endotracheal tube. A ventilatory assist system and method using the device are also disclosed.
