The relationship of fluid restriction during the 1st month of life to the occurrence and severity of bronchopulmonary dysplasia in low birth weight infants: a 1-year radiological follow up

Abstract

One hundred consecutive low birth weight (LBW) infants (less than 1751 g) were randomized into a study group having a restricted fluid intake until 4 weeks of age and a control group following the fluid regimen conventionally used in the hospital. Chest X-ray films were examined on admission, at the ages of 3 days, 7 days, 2 weeks and 4 weeks and at 2-monthly visits to the outpatient clinic up to 1 year of age or until the chest examinations were normal. The severity of hyaline membrane disease (HMD) and typical radiological abnormalities of bronchopulmonary dysplasia (BPD) were assessed. Twelve patients succumbed, one in the study group and 11 in the control group. The study group seemed experience less severe HMD than the controls. Fifty-four percent of the former and 32% of the latter were alive and had no radiological signs of BPD at 4 weeks of age (P less than 0.05). The difference between the groups in the cumulative number of normal chest X-ray examinations during the follow up was even more significant. The percentage of normal X-ray films at 1 year of age was 92% in the study group and 72% in the control group. These results suggest that fluid restriction for the first 4 weeks of life can lower the incidence of radiological abnormalities typical of BPD obtained during the 1st year of life in LBW infants. Pulmonary oedema seems to be a significant aetiological factor causing HMD to develop into chronic lung disease.