Nasal High Frequency Oscillatory Ventilation Versus Nasal Continuous Positive Airway Pressure in Late-Preterm and Term Infants With Transient Tachypnea of the Newborn: a Randomized Controlled Trial

BACKGROUND: Non-invasive High Frequency Oscillatory Ventilation (nHFOV), aims to combine the efficacy of high frequency ventilation with the gentleness of non-invasive support and current evidence suggests that nHFOV may be superior to other non-invasive modes in terms of supporting alveolar ventilation. There are now several published neonatal studies of nHFOV therapy as a rescue mode even in the premature infants; however to date no studies have been published on the efficacy of nHFOV as a primary mode of non-invasive support. The investigators aim to assess the efficacy of nHFOV in late-preterm and term infants with transient tachypnea of the newborn as the primary mode of non-invasive support.

METHOD: The investigators propose to test the effectiveness of nHFOV in late-preterm and term neonates with transient tachypnea of the newborn (TTN) with a Silverman Score of 4 or above on admission who require non-invasive respiratory support. Nasal high frequency oscillatory ventilation may be effective in decreasing duration of non-invasive respiratory support and total oxygen therapy (H1 hypotheses).

The current literature estimates the incidence of transient tachypnea of the newborn to be 5.7 per 1000 births. Assuming that a 5% difference of the primary outcome between the groups is significant, when the alpha value is set at 0.05 and power of the study at 80%, 220 infants must be recruited for each arm (nCPAP and nHFOV) under investigation.

Chest X-ray, complete blood count, C-reactive protein and capillary blood gas analysis (as per unit protocol) will be obtained upon admission to the neonatal intensive care unit. A Silverman Score will be obtained for each participant upon admission and those with a score of 4 and above will be supported with one of the methods (with randomization).

Initial nHFOV settings are: MAP: 8cmH2O, Frequency:10 MHz, Amplitude:35 cmH2O (will be adjusted to achieve adequate chest wall vibration), I:E=1:1 and FiO2: adjusted to keep preductal sPO2 between %90-95. Initial nCPAP settings are: PEEP:6 cmH2O and FiO2: adjusted to keep preductal sPO2 between %90-95. Failure of the primary mode is defined as FiO2 requirement of >%60, capillary blood gas obtained at the 4th hour of therapy showing pH<7.20 or pCO2>65 cmH2O. When nCPAP or nHFOV failure occurs, nasal intermittent positive pressure ventilation (nIPPV) will be applied as a rescue therapy with the following settings: Frequency:30/min, PIP:18 cmH2O, PEEP:6 cmH2O, inspiration time:0.50 sec., inspiratory flow:10 L/min, FiO2:adjusted to keep preductal sPO2 between %90-95. If the rescue mode fails, the infant will be intubated and conventional mechanical ventilation will be initiated.