Hamaekers et al. A bench study of ventilation via two self-assembled jet devices and the Oxygen Flow Modulator in simulated upper airway obstruction. Anaesthesia. 2009 Dec;64(12):1353-8

To reduce the risk of air trapping and to increase oxygenation efficacy an emergency transtracheal ventilation device needs to allow both inspiration and expiration. In absence of such a device Prof. Enk and his co-workers determined the capability of two self-assembled, three-way stopcock based jet devices and the Oxygen Flow Modulator to function as a bidirectional airway in conjunction with a small lumen catheter.