Various embodiments of a tracheal tube having a suction lumen are provided. For example, the suction lumen may be associated with two spaced apart pressure transducers, whereby a pressure drop between the transducers indicates that the suction lumen is free of blockages and a characteristic lack of pressure drop and/or particular pressure curve is indicative of a blockage. In addition, embodiments may include a tracheal tube with sensors configured to sense a buildup of secretions. The sensors may be located proximate to an opening in the suction lumen. In other embodiments, a blockage-clearing system for a suction lumen may be provided that blows air into the suction lumen to clear blockages. In particular, in certain embodiments, the blockage-clearing system may operate to create its own pressurized air source by utilizing the pressure change created in the suction line by a blockage.