Open AccessLongitudinal Evaluation of Pulmonary Function in Premature Infants
Author(s) -
Abigail Settle,
Christina Tiller,
Jeffrey Bjerregaard,
Marylyn Robinson,
James E. Slaven,
Robert S. Tepper
Publication year - 2021
Publication title -
proceedings of imprs
Language(s) - English
Resource type - Journals
ISSN - 2641-2470
DOI - 10.18060/25703
Subject(s) - medicine , dlco , gestational age , pulmonary function testing , air trapping , pediatrics , full term , premature birth , bronchopulmonary dysplasia , demographics , lung function , lung , pregnancy , diffusing capacity , demography , sociology , biology , genetics
Background:
Infants born premature have decreased pulmonary function compared to full-term infants. Longitudinal infant studies are needed to determine whether impaired pulmonary function following premature birth demonstrates catch-up growth. This study measured airway and parenchymal function in infants born premature at approximately 6 months and 1 year of age to assess growth and the effects of gestational age (GA) and sex.
Methods:
37 infants born premature participated in two study visits (V1 and V2) at Riley Hospital in Indianapolis, IN. While sleeping, forced expiratory maneuvers were preformed to measure airway function. DLCO, diffusion capacity of the lung, and VA, alveolar volume, were measured under conditions of room air. Z scores were calculated to compare infants born premature and full-term, adjusting for size, race, and sex.
Demographics:
The subjects consisted of 21 females and 16 males. There were 7 subjects born at 24 – 28 weeks, 6 at 29 – 31 weeks, and 24 at 32 – 36 weeks.
Pulmonary Testing Results:
Variable
Z Score
V1
V2
V2-V1
Male
Female
GA
DLCO
-0.17
(-0.59, 0.26)
*-0.75
(-1.18, -0.31)
*-0.58
(-1.03, -0.12)
*-0.86
(-1.42, -0.30)
-0.05
(-0.53, 0.43)
*0.13
(0.001,0.28)
VA
0.06
(-0.24, 0.45)
-0.24
(-0.70, 0.23)
-0.30
(-0.72 ,0.14)
-0.14
(-0.71, 0.43)
-0.04
(-0.53, 0.45)
0.09
(-0.05, 0.23)
FVC
*-0.38
(-0.60, -0.17)
**-1.05
(-1.36, -0.74)
**-0.67
(-0.98, -0.36)
**-0.71
(-1.04, -0.38)
**-0.72
(-1.01, -0.44)
0.07
(-0.01, 0.15)
FEF50
**-0.88
(-1.15, -0.62)
**-1.36
(-1.63, -1.08)
*-0.47
(-0.80, -0.14)
**-1.12
(-1.44, -0.79)
**-1.12
(-1.40, -0.84)
**0.15
(0.07,0.23)
FEF75
**-0.57
(-0.88, -0.26)
**-1.16
(-1.48, -0.83)
*-0.59
(-0.93, -0.24)
**-0.76
(-1.16, -0.35)
**-0.97
(-1.32, -0.62)
**0.21
(0.11,0.31)
* = p < 0.05 ** = p < 0.001
DLCO was decreased in male subjects compared to female subjects and male full-term infants. VA was not significantly different between subjects and full-term infants. Compared to full-term infants, subjects had decreased forced vital capacity (FVC) and forced expiratory flow at 50% and 75% vital capacity (FEF50 and FEF75). DLCO, FVC, FEF50, and FEF75 exhibited a significant decrease in pulmonary function from V1 to V2 among subjects. Gestational age showed a positive relationship for DLCO, FEF50, and FEF75.
Conclusion and Potential Impact:
The subjects did not exhibit catch-up growth, or an increase in z score from V1 to V2, in parenchymal and airway function for DLCO, FVC, FEF50, and FEF75. Gestational age and sex were factors affecting pulmonary function. As premature infants are born with lower pulmonary function than full-term infants, it is important to understand how lungs continue to develop after release from the NICU.