Noninvasive approach to estimate ventilatory mechanics in spontaneous breathing with different PEEP and pressure support values: Validation with mechanical simulation

Abstract

Measuring or estimating the state of the ventilatory mechanics, expressed in airway resistance and compliance of ventilatory system, and muscles effort are useful in mechanically ventilated patients to identify the level of obstruction or restriction in lung diseases and if the presence of respiratory muscle weakness is evident, the decision making concerning right time for extubation is a clinical issue of interest. Traditionally, the ventilatory mechanics has been estimated in sedated patients under controlled ventilation modes. However the available approaches are not appropriate in the case of spontaneous ventilation during the weaning test. This article presents an approach to evaluate ventilatory mechanics and respiratory muscle effort under spontaneous ventilation in different levels of positive end-expiratory pressure and pressure support, that has been tested using an advanced breathing mechanical simulator. This procedure allowed proper estimation of ventilatory mechanics and respiratory muscle effort in line with simulator settings.