Lung function in infants with congenital diaphragmatic hernia.

<bold>Introduction:</bold> Long-term pulmonary outcomes of congenital diaphragmatic hernia (CDH) have shown airflow obstruction in later childhood, while there are few data in early childhood. We studied lung function in the first months of life in a contemporary cohort of CDH survivors. <bold>Methods:</bold> Prospective study. Exclusion criteria: complex congenital malformations, palliative care. Lung function tests (LFT) were scheduled every 3-6 months. Tidal breathing flow volume loop and multiple-breath nitrogen washout were performed using the Exhalyzer D (EcoMedics, Switzerland) during spontaneous sleep according to current guidelines. Variables were compared to published predicted values for age at assessment. Associations with perinatal data were explored. <bold>Results:</bold> 8 children (5M,3F) underwent LFT (4 twice, 1 four times). Mean birth weight: 3200 g; median age at surgery: 4 days; median days on endotracheal ventilation: 10.5; 6 infants had pulmonary hypertension. Median age at 1st evaluation: 2 months (2 infants were assessed at 12 months for the first time), median age at 2nd evaluation: 5 months; 2 infants had wheezing requiring steroids and salbutamol before the 2nd test. Table 1 shows the results. We found no associations between abnormal LFT and other factors. <table-wrap><object-id>erj;64/suppl_68/PA4096/T1</object-id><object-id>T1</object-id><object-id>t1</object-id><table><colgroup><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td><bold>1st test</bold></td><td><bold>2nd test</bold></td></tr><tr><td>Low TV, n</td><td> 6/8 </td><td>1/4</td></tr><tr><td>High RR, n</td><td>4/8</td><td>0/4</td></tr><tr><td>Low tPTEF/tE, n</td><td>1/8</td><td>3/4</td></tr><tr><td>Low MV, n</td><td>2/8</td><td>2/4</td></tr><tr><td>Abnormal FRC, n</td><td> 3/3 (1 low, 2 high) </td><td> 1/1 (high) </td></tr><tr><td>High LCI₅, n</td><td>0/3</td><td>0/1</td></tr><tr><td>High LCI_2.5, n</td><td>1/3</td><td>1/1</td></tr></tbody></table></table-wrap> <bold>Conclusion:</bold> Many survivors of CDH had abnormal LFT in early childhood: TV increased whereas tPTEF/tE, RR and MV decreased over time. FRC was high in most cases, ventilation inhomogeneity often evident. <bold>References</bold> Willemse L, et al. AnnalsATS 2016;13:2099-2101 Lu Z, et al. ERJ Open Res 2021;7:00301-202