Comparison of methods for tracheal pressure estimation during HFPV

Intubation and mechanical ventilation are frequently used in case of impaired gas exchange. High-frequency percussive ventilation (HFPV) is a nonconventional ventilation modality, which has been proven highly useful in the treatment of several different pathological pulmonary conditions. The pressure measured by the ventilator represents the sum of the tracheal pressure and of the pressure dissipated by endotracheal tube. Given that HFPV is not an intuitive ventilatory modality, the possibility to know the real value of tracheal pressure will be very helpful to optimize the treatment. This study compares two different methods for the estimation of the tracheal pressure in order to ascertain the applicability and limitations of these approaches in the clinical practice. The two models are based on fluid dynamics and on genetic programing. The simple former model for estimation of tracheal pressure showed to be effective and easily applied in everyday clinical practice.