ABSTRACT
<p><b>OBJECTIVE</b>To investigate the efficacy of heated humidified high-flow nasal cannula (HHHFNC) and nasal continuous positive airway pressure (nCPAP) in preterm infants aged 26-31(+6) weeks with respiratory distress syndrome after ventilator weaning.</p><p><b>METHODS</b>A total of 161 preterm infants were randomly divided into two groups after ventilator weaning: HHHFNC treatment (n=79) and nCPAP treatment (n=82). The two groups were subdivided into 26-28(+6) weeks and 29-31+6 weeks groups according to the gestational age. The treatment failure rate, reintubation rate within 7 days after extubation, incidence of complications, and mortality during hospitalization were compared between the two groups.</p><p><b>RESULTS</b>The treatment failure rate and reintubation rate showed no significant differences between the HHHFNC and nCPAP groups. The preterm infants aged 26-28(+6) weeks in the HHHFNC group had a significantly higher treatment failure rate than those in the nCPAP group (P<0.05), while the reintubation rate showed no significant difference. As for the preterm infants aged 29-31(+6) weeks, the treatment failure rate and reintubation rate showed no significant differences between the two groups. The incidence of complications and mortality showed no significant differences between the HHHFNC and nCPAP groups.</p><p><b>CONCLUSIONS</b>In preterm infants aged 29-31(+6) weeks, HHHFNC has a similar efficacy as nCPAP after ventilator weaning, while in those aged less than 29 weeks, HHHFNC should be used with great caution if selected as the first-line noninvasive respiratory support.</p>