Expiratory Ventilation Assistance and Ventilation through Narrow Tubes

A major challenge of airway management is safe care of the patient with a narrowed airway. Small tracheal tubes offer one solution but pose a problem with ventilation. While inspiration may be achieved by use of a high-pressure source to overcome airway resistance, two problems exist: first, the high-pressure source demands technical excellence and exposes the patient to a high risk of barotrauma; second, conventional (passive) exhalation through a narrow tube is slow and cannot achieve a normal minute ventilation with a tracheal tube of less than 4.5 mm diameter. Recently technical developments have led to the ability to assist expiration and make it, like inspiration, an active process. This technology is used in the Ventrain manual ventilator, the 2.4 mm wide Tritube tracheal tube and the Evone automatic ventilator. These new devices and the applied technology enable solutions for safe management of the narrowed upper airway.