Expiratory pressure curve analysis for estimation of lungs mechanics

The analysis of an expiratory pressure curve by using an extra small pneumatic compliance is presented in this paper. The investigations of dynamic courses were performed for a very short time (<200 ms), and basic mechanical parameters of lungs were calculated. For analysis of measurement signals and monitoring of measurement circuit a new computer system was used. The measurement circuit was based on mechanical lungs model. The results of studies have shown that the applied method can be used for estimation of lungs compliance but to determine an airway resistance from the time constant an additional measurement of the flow rate curve is needed. The discussed method of lungs mechanics estimation in independent of ventilatory support.