Short Term Effects of Synchronized vs. Non-synchronized NIPPV in Preterm Infants: Study Protocol for an Unmasked Randomized Crossover Trial.

Respiratory problems are one of the major issues to deal with in preterm newborns.

Because of the immaturity of respiratory mechanisms and structures, the use of supporting devices is often necessary. These include both conventional mechanical ventilation (MV) techniques, which require the use of an endotracheal tube, as well as non-invasive ventilation (NIV) techniques that use softer ventilator-patient interfaces. Increasing attention is payed to the latter ones as less aggressive and associated with better outcomes both in terms of mortality and short and long-term complications, such as bronchopulmonary dysplasia (BPD).

Nasal intermittent positive pressure ventilation (NIPPV) is a NIV technique in which newborn airways are kept open between two pressure levels: peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP). The frequency and duration of each phase are defined by setting the inspiratory and expiratory times or the ventilation rate.

This technique has already shown its superiority in terms of reduced duration of MV, reduced necessity of intubation, decreased failure of extubating and reduced prevalence of BPD if compared with non-invasive techniques based on continuous pressure support, such as continuous positive airway pressure (CPAP). Recent meta-analyses of studies where NIPPV has been used as an alternative to CPAP following extubation show that it reduces need for re-ventilation and air leaks but without any reduction in BPD: there is insufficient evidence to recommend NIPPV as primary mode of respiratory support in the delivery room.

It should be specified that the ventilation rate on NIPPV does not reflect the real respiratory rate (RR) of the newborn, as the ventilator supplies the PIP regardless of newborn respiratory efforts. To reproduce a more physiological and gentle ventilation new devices able to detect newborn respiratory efforts and consequently supply a PIP have been developed to synchronize the ventilation rate with RR of the newborn.