Regional and overall ventilation inhomogeneities in preterm and term-born infants.
OBJECTIVE
We compared ventilation inhomogeneity assessed by electrical impedance tomography (EIT) and multiple breath washout (MBW) in preterm and term-born infants. We hypothesised that EIT measurements in spontaneously breathing infants are repeatable and that differences in regional ventilation distribution measured by EIT can distinguish between preterm and term-born infants.


METHODS
Cross-sectional group comparison study.


METHODS
Lung function laboratory at a University Children's Hospital.


METHODS
Seventeen healthy term-born and 15 preterm infants at a matched postmenstrual age of 44 weeks.


RESULTS
We concurrently measured ventilation inhomogeneity by EIT, ventilation inhomogeneity (LCI) and functional residual capacity (FRC) by MBW and tidal breathing variables during unsedated quiet sleep. EIT measurements were highly repeatable (coefficient of variation 3.6%). Preterm infants showed significantly more ventilation of the independent parts of the lungs compared to healthy term-born infants assessed by EIT (mean difference 5.0, 95 CI 1.3-8%). Whereas the two groups showed no differences in lung volumes or ventilation inhomogeneities assessed by MBW, EIT discriminated better between term and preterm infants. (FRC/kg: mean difference 1.1 mL, 95% CI -1.4-3.8 mL; LCI: mean difference 0.03, 95% CI -0.32-0.25).


CONCLUSIONS
EIT shows distinct differences in ventilation distribution between preterm and term-born infants, which cannot be detected by MBW. Although preterm infants are capable of dynamically maintaining overall functional residual volume and ventilation distribution, they show some spatial differences from fullterm infants.
Riedel
Thomas
T
Paediatric and Neonatal Intensive Care, Department of Paediatrics, Inselspital, University Children's Hospital, University of Bern, 3010, Bern, Switzerland. thomas.riedel@insel.ch
Kyburz
Manuela
M
Latzin
Philipp
P
Thamrin
Cindy
C
Frey
Urs
U
D005260:Female; D005652:Functional Residual Capacity; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D012123:Pulmonary Ventilation; D012890:Sleep / Q000502:physiology