Expiratory trigger setting in pressure support ventilation: From mathematical model to bedside

Abstract

A significant correlation was observed between predicted values of V'ti/V'peak and those values measured in patients undergoing pressure support. These findings should stimulate further research into the possible applications of this mathematical model to optimize expiratory trigger setting. Furthermore, our findings suggest that expiratory trigger should be adjustable and provide a wider range of cutoff levels than that which is currently available.

Patient-Ventilator Interaction During Noninvasive Ventilation in Simulated COPD

“…Furthermore, our results show that the cycling setting must be individualized, since response time of the respiratory system, the interface, amount of pressure support, breathing frequency, and leakage will probably affect how a patient responds. 14,15 Careful analysis of flow and pressure tracings and derived parameters are necessary. We recommend raising cycling criteria above the conventional level as long as parameters suggesting delayed cycling (non-supported inspirations, prolonged mechanical inspiration time, and flow curve analysis) are detectable.…”

“…4 As has been shown for invasive ventilation, adjustment of cycling criteria improves patient ventilator synchronization and reduces intrinsic PEEP. 13,14 However, studies assessing cycling in depth 15 are lacking. The purpose of this lung model study with COPD settings was to systematically investigate how patient ventilator synchronization during NIV with 2 different interfaces (face mask and ventilation helmet) can be improved by adjusting cycling.…”

Cycling of the Mechanical Ventilator Breath

“…[9][10][11][12][13][14][15][16] The reason for multiple studies of flow cycling is attributed to the universal adoption of spontaneous breathing modes such as pressure-support ventilation (PSV). 17 During PSV the patient both triggers and cycles the breath (Fig.…”

ICU mechanical ventilators, technological advances vs. user friendliness: the right picture is worth a thousand numbers

“…Over the last two decades, technological developments have lead to significant improvements of the performances by ICU ventilators [1][2][3][4]. At the same time, the presentation of data and the interface of the ventilator with the clinician have also changed dramatically.…”

“…All parameters were controlled by simple, and in most cases, easily accessible knobs that the clinician simply turned to the desired setting or mode. Today's ICU ventilators are composed primarily of a series of microprocessors controlling a gas delivery platform [1][2][3][4][5]. As a result, the capabilities of today's ICU ventilators are markedly greater than previous generations of ventilators.…”