483 - Lung Recruitment After Birth in Infants with Congenital Diaphragmatic Hernia

Poster Number: 483
Publication Number: 483.231

K. Taylor Wild, CHOP, Philadelphia, PA, United States; Leny Mathew, The Children's Hospital of Philadelphia, Philadelphia, PA, United States; Holly L. Hedrick, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States; Natalie Rintoul, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Anne Ades, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Leane Soorikian, Childrens Hospital of Philadelphia, chester springs, PA, United States; Kelle J. Matthews, Children's Hospital of Philadelphia, Huntingdon Valley, PA, United States; Erin M. Kesler, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Michael Posencheg, Children's Hospital of Philadelphia, Philadelphia, PA, United States; K. Taylor Van Hoose, Children's Hospital of Philadelphia, Philadelphia, PA, United States; John Flibotte, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Howard B. Panitch, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Elizabeth Foglia, Perelman School of Medicine at the University of Pennsylvania, Swarthmore, PA, United States

Background: The delivery room management of infants with congenital diaphragmatic hernia (CDH) is primarily based on expert opinion. Limited data guide delivery room interventions, and ventilatory outcomes are highly variable. Respiratory function monitoring during initial lung aeration may provide insights into the postnatal physiology during initial stabilization after birth.

Objective: To characterize the transitional pulmonary physiology of infants with CDH.

Design/Methods: Single center observational study of all inborn infants with an antenatal diagnosis of CDH. Per hospital protocol, all infants were intubated immediately after birth, and intermittent positive pressure ventilation was initiated with peak inspiratory pressures of 20-25 cm H2O, positive end expiratory pressure of 5 cm H2O, and FiO2 of 0.3-0.5. Respiratory function monitor (RFM) measurements were recorded with a Philips NM3 Respiratory Profile Monitor with VentAssistTM with the sensor placed between the endotracheal tube and respiratory device until the infant was transitioned to a ventilator. Expiratory tidal volume (TV), peak inflation pressure (PIP), peak end expiratory pressure (PEEP), and end-tidal carbon dioxide level (ETCO2) were simultaneously recorded. Statistical analysis included summary statistics of demographic data. RFM parameters were summarized for each minute after birth. A non-parametric regression with a locally weighted scatterplot smoothing (LOWESS) line was developed for TV per birthweight and ETCO2 values at each minute after birth. These values were compared for infants in subgroups defined by liver position on antenatal imaging (thoracic vs abdominal) and extracorporeal membrane oxygenation (ECMO) treatment at any time during the hospitalization.

Results: There were 50 infants with CDH studied from August 2020-December 2021 (Table 1). RFM data were available for 50 infants from the time of intubation until a median of 9 (IQR 7-14) minutes after birth. Tidal volumes per birthweight and ETCO2 values for each minute are shown in Figures 1 and 2. Both values increased for the first 10 minutes of life, but absolute values were heterogenous across the population. Tidal volumes were overall lower and ETCO2 values higher in infants with the liver in the thoracic cavity and infants who were ultimately treated with ECMO.Conclusion(s): Respiratory function immediately after birth is heterogenous for infants with CDH. Lung recruitment, as evidenced by expired tidal volumes and ETCO2 levels, appears to be ongoing throughout the first 10 minutes after birth during invasive positive pressure ventilation.
Table 1: Characteristics of Infants with Congenital Diaphragmatic Hernia (Nf50)
Tidal Volume by time since birthTidal volume (per birthweight) over time for the first ten minutes after birth. Top panel shows the entire cohort, lower panels demonstrate subgroups based on antenatal liver position and postnatal ECMO treatment. A locally weighted scatterplot smoothing (LOWESS) line with 95% confidence interval band in gray is shown.