Lung function and respiratory health at school age in ventilated very low birth weight infants.

OBJECTIVE: To investigate respiratory health and lung function in school-aged children without broncho-pulmonary dysplasia (BPD), who were very low birth weight (VLBWi) and randomized at birth to high frequency oscillatory ventilation (HFOV) or volume guarantee (VG) ventilation for severe respiratory distress syndrome (RDS).

METHODS: In this observational study, 7-y-old ex-preterm infants with severe RDS, randomly assigned at birth to receive assisted/control ventilation + VG (Vt = 5 mL/kg, PEEP = 5 cmH2O)(VG group; mean GA 27 ± 2 wk; mean BW 1086 ± 158 g) or HFOV (HFOV group; mean GA: 27 ± 2; mean BW: 1090 ± 139 g) (both groups were ventilated with Drager Babylog 8000 plus) were recalled. Neonatal clinical data and outcome were known. Actual outcomes were investigated with an interview; lung function was measured by whole-body plethysmography.

RESULTS: Twenty five children were studied (VG group, n = 13 vs. HFOV group, n = 12). There were no differences in anthropometric data, drugs (steroids/bronchodilators and antibiotics) or hospital readmission for respiratory disorders. Compliance to the test was adequate. The authors found a similar obstructive deficit (elevated values: airway resistance (RAW), residual volume (RV), total lung capacity (TLC) with near-normal spirometry) in both groups suggesting a persistent airflow limitation even in absence of BPD.

CONCLUSIONS: VLBW infants even in absence of BPD, need long term respiratory follow-up, because they frequently show an impairment of lung function, independent from initial respiratory support, even if at birth the choice is a lung protective approach (e.g., HFOV or VG ventilation).