Background Nasal flow-synchronized intermittent mandatory ventilation (NSIMV) is a new non-invasive ventilatory mode that delivers synchronized mechanical breaths through the nasal tube.

This study was conducted to compare the efficacy of NSIMV and NCPAP (nasal continuous positive airway pressure) in reducing reintubation of extubated preterm infants.

Methods This randomized clinical trial was conducted in Ghaem NICU of mass had medical university from September 2009 through June 2010.

Preterm infants who had respiratory distress syndrome and required endotracheal intubation within 48h of birth and met specific predetermined criteria for extubation by day 30 of life were recruited. Each infant was randomized to receive either NSIMV or NCPAP soon after extubation. Extubation was deemed successful if re-intubation was not needed for at least 48h. Brain sonography was done befor extubation and after 48^h.sample size was determined with 95% confidence and 90% power. Data was analyzed with spss 11.5 and Chi-square test.

Results There were no significant differences in clinical characteristics between the two groups at randomization.

Fifty-four percent (14/25) infants were successfully extubated to NSIMV compared with 52% (13/25) to NCPAP (p =0.78). Infants assigned to NCPAP had higher arterial CO₂ pressure level than those assigned to NSIMV (p=0.002).

Neither procedure induced major adverse effects despite more elevation in IVH grade during SIMV.

Conclusions NSIMV in the post-extubation period is safe, however it’s not more effective than NCPAP in preventing re-ventilation.