Experimental Assessment Of Variable Assisted Ventilation In Diseased Lungs: A Synchrotron Imaging Study

Mechanical ventilation is a life-saving intervention in acute respiratory failure, and routinely used for life-support under general anaesthesia. There is a considerable body of evidence however that prolonged positive pressure ventilation can induce or worsen injury to the lung tissue through exaggerated mechanical stress, a condition termed ventilator-induced lung injury (VILI). Experimental and clinical studies have shown that mechanical ventilation with some degree of variability, or so-called “noise” in the amplitude of individual breaths is beneficial, both for gas exchange and the mechanics of the respiratory system. However, the mechanisms responsible for the benefit of noise in positive-pressure ventilation are not fully understood. We recently described an imaging technique that allows mapping the dynamic changes in regional lung function as well as strain distribution, within a single respiratory cycle, under mechanical ventilation. The technique uses dual energy synchrotron radiation beams to image the quantitative distribution of contrast elements such as inhaled stable Xe gas within the airspaces, or injected iodine in blood. In this collaborative study between University of Geneva and Geneva University Hospital Dept. of Anaesthesiology and Intensive Care Medicine, and the University of Grenoble Alpes Synchrotron Radiation for Medical Research Laboratory (EA-7442), we propose to test the hypothesis that some degree of variability in assisted ventilation improve recruitment, reduce functional inhomogeneity and strain distribution, using this synchrotron imaging technique. We expect the insight into the impact of variable assisted ventilation gained from synchrotron imaging to help develop better protective ventilation modalities for patients with acute respiratory failure.

Participants

Prof. Walid Habre MD, Université de Genève, Hôpitaux Universitaires de Genève, Département d'Anesthésie

Dr Gergely Fodor MD, Université de Genève, Hôpitaux Universitaires de Genève, Département d'Anesthésie

Dr André Rocha Dos Santos MD, Université de Genève, Hôpitaux Universitaires de Genève, Département d'Anesthésie

Mr Xavier Belin, Université de Genève, Hôpitaux Universitaires de Genève, Département d'Anesthésie

Prof. Sam Bayat MD, Université Grenoble Alpes, Clinique de Pneumologie et de Physiologie

Mr Luca Fardin, Université Grenoble Alpes, Clinique de Pneumologie et de Physiologie