Hyper-protective mechanical ventilation by gas exchange-optimizing ventilation profiles

• Applicant: Professor Dr. Stefan Schumann
• Subject Area: Anaesthesiology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 491044344

Mechanical ventilation is the main life-saving therapy when a patient is under general anaesthesia or suffers from a lung disease. High tidal volumes and associated high pressures, high flow rates, inhomogeneous gas distribution and tidal respiratory recruitment/de-recruitment of lung tissue lead to cyclic mechanical load that can overburden the lung parenchyma. Under conventional mechanical ventilation, mandatory or provided as augmented spontaneous breathing, the course of expiration follows a rapid exponential decay function, the time constant of which is determined by compliance and resistance of the (as the case may be pathologically altered) respiratory system. The "flow-controlled expiration" (FLEX) and the sinusoidal ventilation (SINE) developed in our research group are characterised by active control of the total ventilation period.In small and large animal models of the ventilated respiratory system, FLEX and SINE resulted in less lung damage and reduced focal inflammation, as well as improved compliance and more efficient gas exchange compared to conventional ventilation with passive expiration. Based on our preliminary work, we designed a new approach to optimise the temporal pattern of ventilation with the aim of improving pulmonary gas exchange. By combining a linear with a sinusoidal pattern we created the LINUS ventilation pattern. In this project we investigate the effects of the LINUS ventilation pattern with regard to improving gas exchange and its lung-protective potential. Thereby, the focus is on the reduction of tidal volume and respiratory rate as well as on the lung-protective effects of the decelerated ventilation pattern itself.In order to gain comprehensive insights into the underlying mechanisms and the lung-protective potential of the new ventilation pattern, series of experiments will be conducted in small animal models of the mechanically ventilated healthy respiratory system and the respiratory system in acute lung failure.

• DFG Programme: Research Grants