Effect of Volume Guarantee in Preterm Infants on High-Frequency Oscillatory Ventilation: A Pilot Study.

Objectives  Although adding volume guarantee (VG) to conventional ventilation has been a well-established respiratory management for preterm infants, the evidence of VG combined with high-frequency oscillatory ventilation (HFOV) has not been studied well. The aim of this study was to investigate the effect of VG added to HFOV on respiratory and other physiological parameters. Methods  We conducted a pilot study in extremely low-birth-weight infants ventilated with HFOV + VG with stable pulmonary status after 28 days of age. VG was applied for 6 hours and removed for the following 6 hours, and data were collected during these 12 hours. Results  Six neonates were included in this study (gestational age: 22w5d-23w6d, birthweight: 424-584 g). High-frequency expired tidal volume per weight and amplitude were similar between periods with and without VG. Fluctuation of SpO2 , but not heart rate, was significantly smaller when babies were ventilated with VG than without VG. Fluctuation of minute volume and carbon dioxide diffusion coefficient significantly increased after VG removal. The proportion of time with SpO2  < 80% was decreased by VG overall, especially in three cases. Conclusion  This pilot study suggests VG combined with HFOV attenuates fluctuation of SpO2 and CO2 clearance, which may prevent hypoxemia and hypocapnia.