IPFT | IPFT indices | Unit | Children with ARI episode(s) during infancy (n=173), median (IQR) | Children without documented ARI episode during infancy (n=52), median (IQR) | P-value |
TBFVL | VT/kg | mL/kg | 11.3 (9.7–13.5) | 11.6 (10.2–13.8) | 0.7 |
MTEF | mL/s | 130 (107–157) | 120 (98–138) | 0.05 | |
tPTEF/tE | % | 39.6 (30.5–50.1) | 37.7 (29.6–46.8) | 0.19 | |
TEF25 | mL/s | 153 (124–185) | 135 (110–173) | 0.02 | |
TEF10 | mL/s | 121 (97–148) | 107 (82–139) | 0.04 | |
TEF25/PTEF | % | 79.7 (72.1–85.9) | 76.1 (68.6–83.8) | 0.04 | |
TEF50/PTEF | % | 89.8 (86.1–93.1) | 87.3 (85.5–89.2) | 0.002 | |
RTC | Vʹmax,FRC | mL/s | 57.5 (0–105) | 50 (0–95) | 0.8 |
RVRTC | FEV 0.5 | mL | 58.2 (41.6–81.6) | 68 (45.3–101.8) | 0.04 |
FEV 0.75 | mL | 79.4 (58.1–106.9) | 89.9 (69.6–125.1) | 0.02 | |
FEV1.0 | mL | 96.8 (74.4–124.8) | 112.5 (77.3–139.7) | 0.04 | |
FEV | ml | 119.4 (85.6–144.3) | 137 (117.9–164.5) | 0.004 | |
MEF25 | mL/s | 125 (90–185) | 177.5 (100–310) | 0.01 | |
MEF10 | mL/s | 80 (60–135) | 130 (70–260) | 0.003 | |
FEF25–75 | mL/s | 154.7 (103.6–216.2) | 212.5 (123.2–301.9) | 0.01 | |
PEF | mL/s | 252.5 (180–355) | 282.5 (205–400) | 0.14 |
FEF25-75, forced expiratory flow between 25-75% of FVC; FEV, forced expiratory volume; FEV0.5/FEV0.75/FEV1.0, forced expiratory volume in 0.5/0.75/1.0 sec, maximum expiratory flow at 25% or 10% of FVC (MEF25/MEF10); IPFT, infants pulmonary function test; MTEF, mid tidal expiratory flow; PEF, peak expiratory flow; RTC, rapid thoracoabdominal compression; RVRTC, raised volume rapid thoracoabdominal compression; TBFVL, tidal breathing flow-volume loop; TEF10 or TEF25 or TEF 50/PTEF, ratio of TEF10, TEF25 or TEF50 to peaked tidal expiratory flow; TEF 10/TEF25/TEF50, tidal expiratory flow when 10/25 50 % of VT remaining for expiration; tPTEF/tE, the ratio of time to peak tidal expiratory flow to total expiratory time; Vʹmax, FRC, maximal flow at functional residual capacity; VT/Kg, tidal volume per unit bodyweight.