Low birth-weight nfants (n = 22) recovering from respiratory distress syndrome and requiring CPAP for greater than 24 hours were randomized to receiving CPAP either with bi-level nasal CPAP or conventional nasal CPAP (there was no blinding of interventions). Their average age was 33 days, and they were, on average, receiving around 30% supplemental oxygen with a CPAP level of 6 cms of water. No differences were noted between the two groups in oxygen saturation, transcutaneous CO2, other physiological parameters, frequency of apnea, bradycardia or desaturations.

Bi-level CPAP does not improve gas exchange when compared with conventional CPAP. Lampland et al, 2015