%0 Journal Article %A Diane Gray %A Dorottya Czövek %A Lauren Willemse %A Ane Alberts %A Zoltán Gingl %A Heather J. Zar %A Peter D. Sly %A Zoltán Hantos %T Non-invasive measurement of respiratory impedance in unsedated healthy infants %D 2014 %J European Respiratory Journal %P 186 %V 44 %N Suppl 58 %X Background: Assessing lung mechanics non-invasively in healthy infants offers the potential to better understand lung growth and function. The forced oscillation technique (FOT) requires minimal co-operation from the patient, but has rarely been used in infants.Aim: To assess the feasibility of a modified FOT to measure respiratory mechanics in unsedated infants.Method: Infants enrolled in a birth cohort study in South Africa had lung function measured at 6 to 10 weeks of age using FOT. Respiratory impedance (Zrs) was measured in the frequency range 8-48 Hz via a facemask during natural sleep. Respiratory system resistance (R), compliance (C) and inertance (I) were calculated from the Zrs data.Results: Of the 219 infants tested, 198 (90%) infants had successful measurements. The mean (SD) values of R, C and I were 52.2 (18.1) hPa.s.L-1, 0.83 (0.4) mL.hPa-1 and 0.071 (0.041) hPa.s2.L-1, respectively. Gender was a determinant for R and C, while C was significantly affected by maternal smoking during pregnancy.View this table:Resistance (R), Compliance (C) and Inertance (I) by gender and maternal smokingConclusion: The modified FOT technique is a feasible method for measuring respiratory mechanics in healthy unsedated infants. The FOT has the potential to be used as a tool in the assessment of determinates of early lung function. %U