No LRTI (n=86) | Viral negative LRTI (n=15) | RSV LRTI (n=27) | Other viral LRTI (n=31) | p Value | |
Postmenstrual age (weeks) | 35.9 (35.3–36.5) | 36.1 (35.7–37.1) | 35.9 (35.3–36.6) | 36.1 (35.6–37.5) | 0.16 |
Weight (g) | 2115 (1871–2418) | 2178 (1978–2477) | 1972 (1830–2170) | 1970 (1829–2336) | 0.10 |
FRC (ml/kg) | 25.9 (23.4–28.0) | 24.7 (21.4–27.4) | 23.8 (21.3–27.8) | 24.2 (22.1–28.6) | 0.54 |
FRC (ml) | 58 (48–65) | 56 (47–63) | 52 (42–61) | 51 (43–55) | 0.10 |
Crs (ml/cm H2O/kg) | 1.55 (1.31–1.71) | 1.47 (1.19–1.53) | 1.35 (1.08–1.59) | 1.23 (1.08–1.73) | 0.11 |
Crs (ml/cm H2O) | 3.2 (2.6–3.6) | 3.4 (2.5–3.9) | 2.8 (2.1–3.6) | 2.9 (2.2–3.2) | 0.031 |
Rrs (cm H2O/l/s) | 70 (60–84) | 69 (62–83) | 74 (64–81) | 82 (67–92) | 0.12 |
Data are expressed as median (range).
Crs, compliance of the respiratory system; FRC, functional residual capacity; LTRI, lower respiratory tract infection; Rrs, resistance of the respiratory system; RSV, respiratory syncitial virus.