Methods. The effect of heated humidified high-flow nasal cannula (HHHFNC), continuous positive airway pressure (CPAP), nasal intermittent positive-pressure ventilation (NIPPV), and nasal high-frequency oscillation ventilation (NHFOV) were compared in preterm infants with respiratory distress.

Results. Between December 2015 and February 2017, a total of 76 preterm infants (gestational age <32 weeks) with respiratory distress were enrolled in this study. Of the patients, 20 received HHHFNC, while 20 received nasal CPAP (NCPAP), 19 received NIPPV, and 17 received NHFOV for respiratory support. The primary outcome was intubation requirement during non-invasive respiratory support. The secondary outcome included duration of non-invasive ventilation, air leak syndrome, abdominal distension, intraventricular hemorrhage, necrotizing enterocolitis (NEC), nasal injury, increased secretions, agitation, and mortality rate. The intubation ratio was higher in the NCPAP (40%) and NHFOV (29.4%) groups when compared with the NIPPV (10.5%) and HHHFNC (11.8%) groups. More nasal injury had developed in the NIPPV (78.9%) and NHFOV (82.4%) groups when compared with the NCPAP (40%) and HHHFNC (35%) groups. Moreover, the viscous secretion that blocked the cannulas was higher in NIPPV (78.9%) and NHFOV (76.5%) groups than NCPAP (25%) and HHHFNC (40%) groups. There were no significant differences in the duration of non-invasive ventilation methods, abdominal distension, NEC, air leak syndrome or mortality in the 4 groups.

Conclusions. The NIPPV and HHHFNC methods can be useful as a primary mode of respiratory support for respiratory distress. However, doctors need to be careful with regard to the complications that may develop. Keywords : non-invasive ventilation, preterm, respiratory support, different techniques, efficiency