Objective Airway resistance(R)and lung compliance(C)under non-invasive positive pressure ventilation(NPPV)conditions were measured using a brief pressure release at the end of expiration,and the measurement accuracy was also evaluated.Methods An NPPV respirator was developed by programming a method for calculating R and C.An experimental platform based on the active servo lung ASL5000 was designed.By simulating a healthy adult(R=5 cmH2 O and C=50 mL/cmH2 O,1 cmH2 O=0.098 kPa),an adult patient with acute respiratory distress syndrome(R=10 cmH2 O and C=30 mL/cmH2 O),and an adult patient with chronic obstructive pulmonary disease(R=20 cmH2 O and C=50 mL/cmH2 O),a series of experiments for calculating the R and C were conducted.Results The maximum relative error of R was-12.67%,which occurred in calculating the R of an average adult.The maximum relative error of C was 17.37%,which occurred when calculating the C values of patients with acute respiratory distress syndrome.Each group of data was analyzed using a paired t-test,which showed statistically significant differences(P>0.05).Conclusions The calculation method for R and C at the end of expiration during NPPV is feasible,and its realization and application will be beneficial for achieving precise and personalized respiratory ventilation.
non-invasive positive ventilationresistance in respiratory tractcompliance