We investigated the urinary output and the timing and degree of weight loss during the first four days of life in infants with respiratory distress syndrome (RDS), in order to see if there was an increased risk of developing chronic lung disease (CLD) associated with these factors. Seventy-four infants, 26 of whom did and 48 of whom did not develop CLD, were enrolled in the study. Urinary outputs, mean weight differences and serum sodium levels of the two groups were compared. There was no statistically significant difference between these two groups regarding risk factors that may affect the urinary output. Urinary output was significantly higher during the first and second days of life in Group 1, compared to Group 2. However, urinary output was significantly higher during the second and third days of life in Group 2. Weight loss was significant during the first and the second day in Group 1 and Group 2 infants, respectively. There was a signficant increase in serum sodium levels of Group 1 infants during the first two days. No significant serum sodium level differences were observed in Group 2 infants. In this study we observed that progression to CLD was associated with daily urinary output rather than with a delay in diuresis. This association was significant from the first day of life.

Keywords: respiratuar distres sendromu, kronik akciğer hastalığı, fizyolojik diürez, yenidoğan, respiratory distress syndrome, chronic lung disease, physiologic diuresis, newborn infant