Am. J. Respir. Crit. Care Med., Volume 164, Number 11, December 2001, 2092-2097

Noninvasive Ventilator Triggering in Chronic Obstructive Pulmonary Disease
A Test Lung Comparison

IAN M. STELL, GRAHAM PAUL, KALOK C. LEE, JOSE PONTE, and JOHN MOXHAM

Departments of Accident and Emergency Medicine, Anaesthetics, and Respiratory Medicine, Guy's, Kings and St. Thomas' School of Medicine, King's College Hospital; and Department of Mechanical Engineering, King's College, London, United Kingdom

To be most effective, noninvasive ventilation (NIV) ventilators should synchronize well with patients' breathing. However, the speed with which different ventilators can respond to the transitions between inspiration and expiration may vary, and abnormal respiratory mechanics and mask leaks may exacerbate this problem. This study explored synchronization using a new test lung model designed to simulate acute exacerbations of chronic obstructive pulmonary disease (COPD). Thirteen ventilators were tested against different combinations of tidal volume (VT), airways resistance (Raw), FRC, and mask leak. These combinations ranged from those of a severe exacerbation of COPD, to a mild condition reflecting the optimal triggering conditions a ventilator is likely to encounter. The triggering delays from the beginning and end of "inspiration" of the test lung, to the appropriate responses from the ventilators were measured. Three of the ventilators had trigger delays less than approximately 120 ms at both the beginning and end of expiration under all conditions. Trigger delays of other ventilators were mainly in the range of 120 to 300 ms, although exceptionally as long as 500 ms. Varying the conditions had a variable but generally small effect on triggering times, suggesting that there is a largely unavoidable element to the triggering delays intrinsic to the design of the ventilators.

This article has been cited by other articles:

				J. C. Borel, A. Sabil, J.-P. Janssens, M. Couteau, L. Boulon, P. Levy, and J.-L. Pepin Intentional Leaks in Industrial Masks Have a Significant Impact on Efficacy of Bilevel Noninvasive Ventilation: A Bench Test Study Chest, March 1, 2009; 135(3): 669 - 677. [Abstract] [Full Text] [PDF]

				M. Ferrer, M. Valencia, J. M. Nicolas, O. Bernadich, J. R. Badia, and A. Torres Early Noninvasive Ventilation Averts Extubation Failure in Patients at Risk: A Randomized Trial Am. J. Respir. Crit. Care Med., January 15, 2006; 173(2): 164 - 170. [Abstract] [Full Text] [PDF]

				R. Costa, P. Navalesi, M. Antonelli, F. Cavaliere, A. Craba, R. Proietti, and G. Conti Physiologic Evaluation of Different Levels of Assistance During Noninvasive Ventilation Delivered Through a Helmet Chest, October 1, 2005; 128(4): 2984 - 2990. [Abstract] [Full Text] [PDF]

				R. Farre, S. J. Lloyd-Owen, N. Ambrosino, G. Donaldson, J. Escarrabill, B. Fauroux, D. Robert, B. Schoenhofer, A. Simonds, and J. A. Wedzicha Quality control of equipment in home mechanical ventilation: a European survey Eur. Respir. J., July 1, 2005; 26(1): 86 - 94. [Abstract] [Full Text] [PDF]

				M. Ferrer, A. Esquinas, M. Leon, G. Gonzalez, A. Alarcon, and A. Torres Noninvasive Ventilation in Severe Hypoxemic Respiratory Failure: A Randomized Clinical Trial Am. J. Respir. Crit. Care Med., December 15, 2003; 168(12): 1438 - 1444. [Abstract] [Full Text] [PDF]

				S. Parthasarathy and M. J. Tobin Effect of Ventilator Mode on Sleep Quality in Critically Ill Patients Am. J. Respir. Crit. Care Med., December 1, 2002; 166(11): 1423 - 1429. [Abstract] [Full Text] [PDF]

				B. Schonhofer and S. Sortor-Leger Equipment needs for noninvasive mechanical ventilation Eur. Respir. J., October 1, 2002; 20(4): 1029 - 1036. [Abstract] [Full Text] [PDF]

				M. J. TOBIN Critical Care Medicine in AJRCCM 2001 Am. J. Respir. Crit. Care Med., March 1, 2002; 165(5): 565 - 583. [Full Text] [PDF]