Ventilator sharing for two patients : individualisation of tidal volumes in volume and pressure-controlled ventilation modes

The COVID-19 outbreak leads to a rapid global increase in the number of patients requiring mechanical ventilation. A potential mismatch between the number of ventilators available and the number of patients requiring one could be avoided by using the same ventilator for ventilation of two patients. This is what is called ventilation sharing. By adding medical-grade filters, valves, and sensors, to this ventilation sharing set-up, it could be possible to provide individualised ventilation. This master thesis aims to test this assumption. Specifically, this work investigates the possibility of individualising tidal volumes for two patients undergoing differential multi-ventilation in volume and pressure-controlled ventilation mode. The ultimate goal is to answer to the medical validation of this way of ventilation sharing. This work contributed to the characterisation of the volume distribution between patients. Firstly, the multi-ventilation differential circuit was set up and volume and pressure sensors were implemented. Secondly, characterisation of different valves, to select the one to be used in the set-up, was performed. Thirdly, a study on the distribution of volumes between two patients was carried out for two different ventilation modes, to determine if volume individuation was possible. A first clinical simulation was also performed. The results of the tests show that the individualisation of tidal volumes is possible in both ventilation modes. However, the use of the pressure-controlled ventilation mode is safer.