Variablea Successful (n=268) Failure (n=92) p-value
Hemodynamically significant PDA: peri-extubation 67 (25%) 46 (50%) <0.001
GA (wks) 27 (25-28) 26 (24-27) <0.001
Birth Weight (gms) 920 (770-1090) 795 (690-914) <0.001
Highest RSS in first 6 hours 3.60 (2.50-4.95) 3.80 (2.58-6.15) 0.045
Gender: Male 129 (48%) 47 (51%) 0.63
Histologic chorioamnionitis 124/253 (49%) 53/84 (63%) 0.03
Complete ANS Course 168/266 (63%) 59/91 (65%) 0.77
Vaginal delivery 84 (31%) 28 (30%) 0.87
Age at extubation (days) 3 (2-10) 4 (2-10) 0.21
PMA at extubation (wks) 28 (27-29) 27 (26-28) <0.001
Weight at extubation (gms) 960 (800-1090) 815 (695-980) <0.001
Post extubation respiratory support (NIPPV/NCPAP vs othersb) 186 (69%) 73 (80%) 0.047
Caffeine use prior to extubation 222 (83%) 83 (90%) 0.09
Pre-extubation VI 5.88 (4.34-7.74) 5.56 (4.43-8.00) 0.83
Pre-extubation Fio2 23 (21-28) 25 (21-30) 0.001
Pre-extubation pH 7.36 (7.30-7.41) 7.34 (7.29-7.37) 0.004