An improved catheter is provided for insertion into a trachea, blood vessel, bladder or urinary tract of a patient. The self cleaning catheter can be easily inserted and removed from the patient without retained, solid components falling into a patient's trachea, blood vessels, bladder, or urinary tract when the catheter is removed from the patient. The self cleaning catheter has a flexible cylindrical sleeve on the exterior of a cylindrical member that can be withdrawn to the interior of the catheter prior to removal from the patient's body. Alternatively, the catheter has a design allowing an end of the catheter to fold inward on itself prior to removal from the patient's body.