Increased alveolar volume and lung diffusion capacity in preterm infants randomized to two extra weeks of continuous positive airway pressure.
In a recent study, Dr. Cindy McEvoy and colleagues present the findings from a six-month follow-up after discharge compared to their earlier research published in 2019 (PMID: 31519441). The original study enrolled infants born ≤ 32 GA who required at least 24 hours of respiratory support via CPAP. Once these infants were stable and no longer in need of respiratory support, they were randomized to be weaned off CPAP (dCPAP) or to continue receiving CPAP (eCPAP) for an additional two weeks. Functional residual capacity (FRC) was assessed in both groups using the nitrogen washout technique at the time of randomization, at the conclusion of the two-week extended CPAP treatment, and upon discharge. Results indicated that infants in the eCPAP group experienced a significant increase in FRC compared to those in the dCPAP group, both from randomization to the end of the two-week therapy (12.6 ml vs. 6.4 ml, p<0.03) and at discharge (27.2 ml vs. 7.1 ml, p<0.01).
In this follow-up study, the authors employed a similar design but extended the follow-up period to compare alveolar volume (VA) and diffusion lung capacity (DLCO) between the two groups at six months corrected gestational age. A total of one hundred infants were randomized into either the intervention or control groups. Successful measurements of VA and DLCO were obtained for 93 out of 99 infants (46 in the dCPAP group and 47 in the eCPAP group). There were no significant differences in GA, birth weight, sex, or race between the groups. Consistent with the original study findings, the new study revealed that FRC was significantly greater in the eCPAP group compared to the dCPAP group at both the end of the two-week treatment period and at discharge. Furthermore, VA was significantly higher in the eCPAP group (492 ± 185) compared to the dCPAP group (412 ± 149), and DLCO was also significantly elevated in the eCPAP group (3.4 ± 1.1) versus the dCPAP group (2.8 ± 0.9).
The authors concluded that given that premature infants often experience impaired alveolarization and vascularization, the observed increases in VA and DLCO may enhance respiratory health and improve lung function trajectories. This study is currently under review for publication in peer-reviewed journal.
These findings contribute to our understanding at the Bubble CPAP Institute and may elucidate results published in PMID: 31952073, which suggested that the improved incidence of chronic lung disease (CLD) in infants treated with bubble CPAP can be partly attributed to prolonged bubble CPAP use until the weaning of respiratory support.
Dr. Cindy T. McEvoy will be a guest speaker at the Bubble CPAP and Non-Invasive Respiratory Management Conference and Workshop, taking place in Washington, DC, on December 7-8, 2024.
Register today at https://lnkd.in/e2UjTk3B
