Two Distinct Controllers for Pressure Regulation in Total Liquid Ventilation

Total liquid ventilation is an experimental method of mechanical assisted ventilation in which lungs are totally filled and then ventilated with a tidal volume of perfluorochemical liquid by using a liquid ventilator. However to apply this approach to humans, liquid ventilators must reach the same level of reliability as conventional mechanical gas ventilators. In control terms, the problem is to design a controller to perform pressure regulated ventilation in spite of large uncertainties on physiological parameters, and nonlinear behavior of the lungs. The presented pressure controlled ventilation mode is similar to those used in conventional gas ventilator excepted that the airway pressure and the positive end-expiratory pressure require two distinct controllers. Simulations, in-vitro experiments and in-vivo results with 5 healthy term newborn lambs have validated the presented controllers.