[Respiratory function and clinical outcome in infants after premature birth and chronic pulmonary disease]

The purpose of this study was to assess the clinical status and respiratory function of infants with premature birth-related pulmonary sequelae and their correlation.

We studied 23 patients with a mean postnatal age of 32 weeks. All infants were born prematurely and developed respiratory disease with radiological features of bronchopulmonary dysplasia. The neonatal clinical status and evolution were quantified by using clinical scoring systems described previously. Parameters of tidal flow volume curves were assessed by pneumotachography. Static compliance and resistance of the respiratory system were obtained using the single-breath occlusion technique. Results were compared with reference values available in the medical literature.

Both the neonatal and evolutive clinical status were given a score of moderate severity. Mean values for weight adjusted compliance and resistance and those for respiratory rate and tidal volume were within the normal range. The mean value for time to peak expiratory flow as a ratio of total expiratory time was under the normal range, showing obstructive airway disease. There was a significant correlation (p < 0.05) between the evolutive clinical score and neonatal clinical score (r = 0.48), compliance (r = 0.50) and respiratory rate (r = 0.67).

Measuring pulmonary function is useful in the follow-up of infants with respiratory disease, providing additional information about the clinical findings, evolution of the illness and subsequent outcome. The development of simple and noninvasive methods explains their increasing application to clinical uses and not exclusively research purposes.