A device for a respirator. A tube is operative to be introduced into a trachea of a patient and supply and discharge gas from the patient's lungs. A first conduit connects the tube to the respirator to discharge exhalation gas. A second conduit extends between the tube and a source of sub-pressure. The second conduit is connected to an exhalation tube of the tube. A third conduit connects the tube to the respirator and supplies inhalation gas. In an active position a valve arrangement keeps the second conduit open and connects the exhalation tube to a source of sub-pressure. In an inactive position the valve arrangement keeps the second conduit closed and the first conduit open. A controller moves the valve arrangement from the inactive position to the active position for a period of time to simulate coughing to cause a gas flow to support transport of secretions.