Table 1– Airway impedance biomarkers
Airway impedance biomarkerClinical interpretation
R20Mean level of airway constriction
R5–R20Heterogeneity of airway constriction
AXHeterogeneity of airway closure
SampEn R20Fluctuation of the mean level of airway constriction over time
SampEn R5–R20Fluctuation of the heterogeneity of airway constriction over time
SampEn AXFluctuation of the heterogeneity of airway closure over time

  • R20: resistance at 20 Hz; R5–R20: resistance at 5 Hz minus R20; AX: reactance area; SampEn: sample entropy.