Physiologic Outcomes of Prematurity
Bronchopulmonary dysplasia (BPD) is the most common short-term
complication of premature birth, and infants with BPD can continue to
have impaired lung function into adulthood [24]. Although there have
been studies comparing lung function between infants with BPD and those
without this diagnosis, there are limited data in preterm infants who
are born small for gestational age (SGA). Kim, et al investigated the
differences in airway obstruction in term, healthy neonates and preterm
neonates with and without BPD using MBW and TBA [25]. No significant
differences in Tpef/Te were observed between the term infants, preterm
infants with mild/moderate BPD, and preterm infants with severe BPD.
However, Tpef/Te was significantly lower in the severe BPD infants
compared to the mild/moderate BPD infants, consistent with worse airway
obstruction in the former group. LCI was significantly increased in
preterm infants compared to term ones, but it did not vary between the
infants with no BPD, mild BPD, or severe BPD, even when accounting for
SGA status. SGA infants with BPD had a significantly lower Tpef/Te than
average for GA matched infants, showing a negative effect of SGA in BPD.
These results suggest that SGA status is a risk factor for worse airway
obstruction in infants with BPD.
Sex differences in lung function and structure are well known, but
studies of sex differences in lung mechanics of preterm neonates are
lacking. Kim, et al measured airway pressure and flow in male and female
neonates requiring mechanical ventilation for neonatal respiratory
distress syndrome, and then used these data to generate a single
compartment model to calculate specific elastance (ES)
[26]. Male infants had higher ES compared to female
infants of matched gestational age and less breath-to-breath variability
in ES. This study suggests that ventilator strategies
may need to take sex into account, but further studies with larger
cohorts are needed.
0.5. There was no significant difference in any other
forced expiratory flow measurements, FRC, or respiratory system
compliance between the caffeine treated or untreated groups. When
further stratified by BPD diagnosis, differences in lung function were
only seen in infants without BPD who had received caffeine. These
results indicate that caffeine may have beneficial effects on lung
function in addition to its effect on reducing risk of BPD.