659 - Response to Aerosolized Calfactant in Preterm Infants with Respiratory Distress Syndrome; A Post Hoc Analysis of AERO-02 trial

Monday, May 1, 2023

9:30 AM – 11:30 AM ET

Poster Number: 659
Publication Number: 659.442

Dinushan C. Kaluarachchi, University of Wisconsin - Madison, Madison, WI, United States; Henry Zapata, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; Heather L. Becker, Madison College, Waunakee, WI, United States; Michael R. Lasarev, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; Prem Fort, Johns Hopkins All Children's Hospital, St. Petersburg, FL, United States; Scott O. Guthrie, Monroe Carell Jr. Children's Hospital at Vanderbilt, Jackson, TN, United States

Presenting Author(s)

Dinushan C. Kaluarachchi, MBBS (he/him/his)

Associate Professor
University of Wisconsin - Madison
Madison, Wisconsin, United States

Background: Aerosolized surfactant treatment is the least invasive method of administering exogenous surfactant for neonates with respiratory distress syndrome (RDS). The largest randomized control trial of aerosolized surfactant (AERO-02 trial) demonstrated a reduction in need for intubation by nearly 50%.

Objective: To determine the oxygenation response and to identify predictors of improved oxygenation after aerosolized Calfactant treatment in moderate to late preterm infants with RDS.

Design/Methods: We conducted a post-hoc analysis of preterm neonates 28 0/7 to 36 6/7 weeks gestation in the AERO-02 trial. Trends in hourly fraction of oxygen (FiO2), mean airway pressure (MAP) and respiratory severity score (RSS) for 72 hours after randomization were compared between the aerosolized surfactant (AS) and usual care (UC) groups. Change in FiO2 before and 4 hours after each aerosolized calfactant was compared. Change in FiO2 after first aerosolized calfactant treatment was analyzed by gestational age (GA), birthweight (BW), age at randomization, and RSS subgroups.

Results: Final study cohort consisted of 189 subjects in AS group and 164 in UC group. Forty-eight percent of subjects in the UC group required intubation at median age of 5 hours compared to 24% subjects in the AS group at a median age of 22 hours (Figure 1). FiO2, MAP and RSS were lower in the UC group for the 72 hours from randomization (Figure 2). Respiratory support at 7 days, pneumothorax, BPD status and length of stay were similar between the two groups. FiO2 decrease was seen after the first aerosolized calfactant dose (p< 0.001), but it did not defer after second (p=0.08) or third doses (p=0.14) (Table 1). There was no evidence to suggest that changes in FiO2 after first aerosolization differed by subgroups of gestational age (p=0.99), birth weight (p=0.52), age at randomization (p=0.56) or RSS at the time of randomization (p=0.20).

Conclusion(s): We noted that FiO2, MAP and RSS were lower in the UC group. This is most likely due to early and higher rate liquid surfactant administration in the UC group leading to improved oxygenation. A modest decrease in FiO2 was noted in the AS group after the first aerosolization but importantly no elevation in FiO2 which required liquid surfactant treatment. Despite higher FiO2, MAP and RSS, the AS group had similar short term respiratory outcomes while avoiding intubation and liquid surfactant.