The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts


Kathy Grilliot, Terri Clark, Rosary Ossorio; Respiratory Therapy, Northern Virginia Community College, Springfield, VA

Background: One way speaking valves can be used during mechanical ventilation but use is limited by nuisance alarms and lack of known functional alternative alarms. Currently there are no valve use protocols available from ventilator manufacturers. This study assessed several brands of ventilators to determine how each ventilator performed with a closed position speaking valve inline, which modes were the most compatible and tested for disconnect alarms. Method: A bench study was performed using a Passy Muir® valve and the following ventilators: the Puritan Bennett 840, Philips Esprit, CareFusion Avea and Vela, Philips Trilogy 200 (active and passive circuits) and Maquet Servo-i. Each ventilator was set up with a standard circuit, closed suction catheter connected to a ventilation mannequin and a PMV 007. The ventilator modes evaluated were SIMV/PC, SIMV/VC, and/or NIV. Settings used were Vt 500 mls or pressure of 20 cmH2O, rate 12 breaths/min, FIO2 0.21, PEEP of 0 cmH2O and PS of 20 cmH2O. Ventilator alarms that activated upon disconnect were noted. Each ventilator was adjusted to a mode and alarm configuration which allowed use of the valve without nuisance alarms but offered a disconnect alarm in less than 15 seconds. Results: The AVEA, VELA, Trilogy 200 with the active circuit and Esprit ventilators each demonstrated compatibility in SIMV/VC and SIMV/PC modes with a functional disconnect alarm in less than 10 seconds. The PB840 and SERVO-i demonstrated compatibility in the NIV mode. The SERVO-i met expectations in less than 10 seconds using the high respiratory rate and high minute ventilation alarms as functional disconnect alarms. The PB840 alarmed low pressure as a yellow caution alarm at 15 seconds but did not reach a red priority alarm status. All ventilators tested met capabilities to cycle off a pressure support breath without returning volumes. Conclusion: The ventilators all functioned well with a closed position speaking valve in line with certain restrictions on the mode selected and alarm settings. A clinical study is warranted to support the results of this bench study. Sponsored Research – Some ventilators were provided by Passy Muir, Inc. and Philips Respironics Sponsored Research - Passy Muir paid the bill to rent the ventilators that we did not own. Philips Respironics lent a ventilator to us.