Brief research report: Chest radiographic thoracic area in term ventilated infants without respiratory disease

Radiographic thoracic area in newborn infants with Down's syndrome

OBJECTIVES

Infants with Down's syndrome (DS) can suffer from lung hypoplasia. Our aim was to determine if the chest radiographic thoracic area (CRTA) on day one of life differed between infants with DS compared to term controls without respiratory disease and whether in infants with DS, the CRTA was related to a longer duration of ventilation and supplemental oxygen therapy.

METHODS

A review of infants with DS born between 2012 and 2023 at King's College Hospital NHS Foundation Trust, London, UK was conducted. The control group consisted of term, newborn infants matched for birth weight and ventilated for poor respiratory drive at birth. Chest radiographs on day one were analysed and the highest CRTA for each infant was included in the analysis.

RESULTS

The 40 infants with DS (18 male) had significantly lower median (IQR) CRTA [1,922 (1,571-2,261) mm2] compared to 80 controls [2,495 (2,108-2,908) mm2, p<0.001]. The CRTA was not related to a longer duration of invasive ventilation, a longer period of supplemental oxygen requirement and was not different in infants with DS with or without significant congenital heart disease or gastrointestinal atresia.

CONCLUSIONS

Newborn infants with Down's syndrome had lower chest radiographic thoracic area compared to healthy term controls, but this finding was not associated with clinical indices of lung disease severity.

Prediction of bronchopulmonary dysplasia by the chest radiographic thoracic area on day one in infants with exomphalos

OBJECTIVES

To determine if infants with exomphalos had abnormal antenatal lung growth as indicated by lower chest radiographic thoracic areas (CRTA) on day one compared to controls and whether the CRTA could predict the development of bronchopulmonary dysplasia (BPD).

METHODS

Infants with exomphalos cared for between January 2004 and January 2023 were included. The controls were term, newborn infants ventilated for absent respiratory drive at birth, without lung disease and had no supplemental oxygen requirement by 6 h of age. The radiographs were imported as digital image files by Sectra PACS software (Sectra AB, Linköping, Sweden). Free-hand tracing of the perimeter of the thoracic area was undertaken and the CRTA calculated by the software.

RESULTS

Sixty-four infants with exomphalos and 130 controls were included. Infants with exomphalos had a lower median (IQR) CRTA (1,983 [1,657-2,471] mm2) compared to controls (2,547 [2,153-2,932] mm2, p<0.001). Following multivariable regression analysis, infants with exomphalos had lower CRTAs compared to controls (p=0.001) after adjusting for differences in gestational age and male sex. In the exomphalos group, the CRTAs were lower in those who developed BPD (n=14, 1,530 [1,307-1,941] mm2) compared to those who did not (2,168 [1,865-2,672], p<0.001). Following multivariable regression analysis, the CRTA was associated with BPD development (p=0.021) after adjusting for male sex and gestational age.

CONCLUSIONS

Lower CRTAs on day one in the exomphalos infants compared to the controls predicted BPD development.