Factors associated with successful extubation
Infants who failed extubation had a higher incidence of hemodynamically significant PDA at extubatio. These infants were also noted to have a lower gestational age, lower birth weight, higher RSS in first 6 hours of age, and higher incidence of histological chorioamnionitis. These infants also had a lower post-menstrual age, lower weight at extubation, higher receipt of nasal CPAP or non-invasive positive pressure ventilation (NIPPV) as post extubation respiratory support, lower pre-extubation pH, and higher pre-extubation Fio2 (Table 1) .
On logistic regression analysis successful extubation was significantly associated with absence of hemodynamically significant PDA (Odds Ratio 0.32, 95% Confidence Interval 0.17-0.61) after adjusting for gestational age, age at extubation, sex, pH at extubation, Fio2 at extubation and highest RSS in first 6 hours of age.