Comparison of nasal intermittent positive pressure ventilation and bubble CPAP with an in-line high-frequency interrupter in a premature infant lung model

Abstract

Introduction: Noninvasive ventilation has become a staple in the care of premature infants. However, failure rates continue to be high in this population. Modifications to noninvasive support, such as nasal intermittent positive pressure ventilation (NIPPV), are used clinically to reduce such failure. Previous in vitro studies have shown improved CO₂ clearance when superimposing high-frequency oscillations onto bubble continuous positive airway pressure (BCPAP).

Objective: To compare the CO₂ clearance of NIPPV to BCPAP with an in-line high-frequency interrupter (HFI) in a premature infant lung model.

Methods: A premature infant lung model was connected to either a Dräger VN500 for delivery of NIPPV or a BCPAP device with superimposed high-frequency oscillations generated by an in-line HFI. Change in end-tidal CO₂ (ETCO₂ ) and mean airway pressure at the simulated trachea were measured and compared for both noninvasive modalities.

Results: Superimposing HF oscillations onto BCPAP with an in-line HFI resulted in improved CO₂ clearance relative to BCPAP alone for all tested oscillation frequencies at all CPAP levels (p < 0.001). NIPPV also resulted in improved CO₂ clearance relative to nasal CPAP (NCPAP) alone (p < 0.001). Among the tested settings, BCPAP with an in-line HFI resulted in decreased ETCO₂ relative to BCPAP ranging from -14% to -36%, while NIPPV resulted in decreased ETCO₂ relative to NCPAP ranging from -2% to -12%.

Conclusion: Superimposing high-frequency oscillations onto BCPAP using a novel in-line HFI was found to be more effective at clearing CO₂ than NIPPV in a premature infant lung model.

Keywords: infant; neonatal pulmonary medicine; noninvasive ventilation; pulmonary function; respiratory technology.