High-frequency oscillatory ventilation for treating neonatal meconium aspiration syndrome

Objective The high frequency oscillatory ventilation (HFOV) has been proved effective both on maintaining gas exchange and decreasing the frequency of chronic lung diseases in neonates with respiratory distress syndrome. The present study aimed to evaluate the safety and effectiveness of HFOV along with the protocol of recruiting and maintaining the optimal lung volume in neonates with meconium aspiration syndrome. Methods Nine neonates (7 males and 2 females) with meconium aspiration syndrome were managed with HFOV. The median age was 12 h (2 40 h), the median gestational age was 41 weeks (40 42 weeks), and the median birth weight was 3 640 g (2 750 4 550 g). During HFOV, the lung volume recruitment strategy was performed, that is, to increase the mean airway pressure and lung volume, and to achieve the arterial oxygen saturation ≥90% and FiO 2 ≤0.4. Modulation of PaCO 2 was accomplished by either varying amplitude pressure or changing oscillatory frequency. The target PaCO 2 was 35 45 mmHg (1 mmHg=0.133 kPa). The heart rate, arterial blood pressure, transcutaneous oxygen saturation, arterial blood gas analysis and the oxygenation index were monitored during the course of the high frequency protocol. Results Eight neonates demonstrated effective with HFOV by improving oxygenation and maintaining gas exchange. The duration of HFOV varied from 2 to 8 (median 5) days. During 48 hours after initiating HFOV, there were steady reductions in both mean airway pressure and FiO 2 .The mean airway pressure decreased from (22±3) cmH 2O to (15±4) cmH 2O ( F =3.52, P 0.05), and FiO 2 decreased from 0 57±0 30 to 0 37±0 19 ( F =2.72, P 0.05). After application of HFOV, there was prompt improvement in oxygenation. The oxygenation index decreased from 13.7±3.1 to 6.1±2.2 ( F =3.58, P 0.05 ). No statistically significant changes was observed in the amplitude pressure, though the median amplitude pressure decreased from (48±7) cmH 2O to (41±7) cmH 2O ( F =1.98, P 0.05). No significant cardiac complication was observed. Conclusion HFOV showed both safe and effective in neonates with meconium aspiration syndrome. A lung volume recruitment strategy during HFOV produced improvement of gas exchange without significant compromise in cardiac function