Fluctuations in Oxygen Saturation during Synchronized Nasal Intermittent Positive Pressure Ventilation and Nasal High-Frequency Oscillatory Ventilation in Very Low Birth Weight Infants: A Randomized Crossover Trial

Abstract

<b><i>Background:</i></b> Very low birth weight (VLBW) infants on noninvasive ventilation (NIV) experience frequent fluctuations in oxygen saturation (SpO<sub>2</sub>) that are associated with an increased risk for mortality and severe morbidities. <b><i>Methods:</i></b> In this randomized crossover trial, VLBW infants (<i>n</i> = 22) born 22+3 to 28+0 weeks on NIV with supplemental oxygen were allocated on two consecutive days in random order to synchronized nasal intermittent positive pressure ventilation (sNIPPV) and nasal high-frequency oscillatory ventilation (nHFOV) for 8 h. nHFOV and sNIPPV were set to equivalent mean airway pressure and transcutaneous pCO<sub>2</sub>. Primary outcome was the time spent within the SpO<sub>2</sub> target (88–95%). <b><i>Results:</i></b> During sNIPPV, VLBW infants spent significantly more time within the SpO<sub>2</sub> target (59.9%) than during nHFOV (54.6%). The proportion of time spent in hypoxemia (22.3% vs. 27.1%) and the mean fraction of supplemental oxygen (FiO<sub>2</sub>) (29.4% vs. 32.8%) were significantly reduced during sNIPPV, while the respiratory rate (50.1 vs. 42.6) was significantly higher. Mean SpO<sub>2</sub>, SpO<sub>2</sub> above the target, number of prolonged (>1 min) and severe (SpO<sub>2</sub> <80%) hypoxemic episodes, parameters of cerebral tissue oxygenation using NIRS, number of FiO<sub>2</sub> adjustments, heart rate, number of bradycardias, abdominal distension and transcutaneous pCO<sub>2</sub> did not differ between both interventions. <b><i>Conclusions:</i></b> In VLBW infants with frequent fluctuations in SpO<sub>2</sub>, sNIPPV is more efficient than nHFOV to retain the SpO<sub>2</sub> target and to reduce FiO<sub>2</sub> exposure. These results demand more detailed investigations into cumulative oxygen toxicities during different modes of NIV over the weaning period, particularly with regard to consequences for long-term outcomes.