Pressure controller and leak detector for tracheal tube cuff

摘要

An inflation control system for the cuff of a tracheal tube includes an adjustable pressure relief valve with an inlet and an outlet connected in series between the cuff and a source of pressurized gas, and a valved exhaust port urged toward the closed condition. When the tracheal tube is connected to an exhalation valve and a volume ventilator with a pulsed exhalation valve drive line, two relief valves are preferred: a low pressure valve in series with a high pressure valve. The low pressure relief valve is controlled by the exhalation drive line, preferably by means of an inflatable balloon in communication with the exhalation drive line. A flow detector in the cuff inflation line produces an electrical output signal indicative of airflow to activate an alarm signifying a continuous airflow condition due to cuff leak. The airflow detector preferably includes a mechanical flow meter in combination with a photoelectric sensor.