Patent ID: 7040321

Claim:
In a method for controlling a flow of breathing gas in a ventilator for assisted or controlled ventilation of a patient as a function of a tracheobronchial airway pressure of the patient, having one of a ventilator tube, a tracheal tube and a tracheostomy tube, which can be introduced into a trachea of the patient and can be subjected to the breathing gas and which has an inflatable cuff and at least one lumen that is continuous from a distal end of the ventilator tube to a proximal end of the ventilator tube, and wherein an airway pressure is detected, the improvement comprising: determining the tracheobronchial airway pressure by one of continuous and intermittent detection and evaluation of an intra-cuff pressure prevailing in the cuff of the tube inserted into the trachea, and controlling the flow of the breathing gas in the ventilator as a function of a detected intra-cuff pressure, determining a pressure difference (ΔP) generated by the ventilator to overcome a flow resistance of the tube as a function of the pressure difference between the pressure at the proximal end of the tube and the tracheobronchial airway pressure at the distal end of the tube by measurement of the pressure at the proximal end of the tube and the intra-cuff pressure, and using a ΔP to calculate a compensatory constant, and adapting dynamically the compensatory constant from one breathing stroke to another breathing stroke during respiration by the ventilator, to a respective current flow resistance of the tube.