Presented at the Neonatal Society 2002 Summer Meeting.
Greenough A1, Thomas M1, Johnson A2, Peacock J2, Marlow N3, Calvert S2
1 Department of Child Health, King’s College Hospital, London, UK
2 Department of Child Health, St George’s Hospital Medical School, London, UK
3 Department of Child Health, University Hospital, Nottingham, UK
Background: Chronic lung disease (CLD) occurs in more than 50% of infants born below 29 weeks of gestation and is associated with significant mortality and morbidity. Although, systemic administration of corticosteroids in the second week after birth can reduce the development of CLD and improve survival, this treatment may have long term adverse effects. It is, therefore, important only to treat those infants at highest risk of CLD.
Aim: To determine whether the chest radiograph (CXR) appearance at seven days predicted CLD development and was a better predictor than readily available clinical data.
Patients: Fifty-nine infants with a median gestational age of 26+1 weeks (range 24+0 to 28+5) and birthweight 768 g (528 to 1097) entered into the UKOS study and cared for at King’s College or St George’s Hospitals.
Methods: Chest radiographs taken at seven days were assessed using a scoring system for the presence of fibrosis/interstitial shadows, cystic elements and hyperinflation. Data were collected regarding gestational age, birthweight, use of antenatal steroids and postnatal surfactant and each infant’s oxygenation index was calculated at 120 hours.
Results: Thirty-nine infants developed CLD (oxygen dependency at 36 weeks PMA). Compared to the rest of the cohort, the CLD infants were not significantly more immature, but had a lower birthweight (p=0.03) and had a higher total CXR score (p=0.0003), with higher scores for fibrosis/interstitial shadowing (p=0.0002). Construction of receiver operator characteristic (ROC) curves revealed that the total CXR score compared to the clinical data had the highest area under the ROC curve (0.88) with regard to prediction of CLD. A CXR score greater than 3 had 85% sensitivity and 78% specificity in predicting CLD.
Conclusion: These results suggest the CXR appearance at seven days is an accurate predictor of CLD development in very immature infants.