| Variable | Group I (n=10) | Group II (n=38) | p |
|---|---|---|---|
| Gestational age at birth (weeks) | 25.8 (1.2) | 26.4 (1.5) | NS |
| Birth weight (g) | 788 (138.3) | 801 (126.7) | NS |
| Age at ligation (d) | 40 (26, 56.2) | 49.7 (30.1, 59.2) | NS |
| PDA size (mm) | 2.85 (2.6, 3) | 3.4 (3.1, 3.8) | 0.03 |
| Left atria/aorta ratio | 1.95 (1.7, 2) | 2.6 (2.3, 2.9) | 0.02 |
| ↑Mean airway pressure by 2 cm H2O | 1/10 (10%) | 13/38 (34%) | 0.03 |
| ↑FiO2>20% | 2/10 (20%) | 12/38 (32%) | 0.04 |
| ↑RSS>50% | 3/10 (30%) | 20/38 (52%) | 0.04 |
| MBP<3rd centile | 1/10 (10%) | 12/38 (31.5%) | 0.03 |
| Post-op inotropes/hydrocortisone | 0 | 8/38 (21%) |
MBP, mean blood pressure; PDA, patent ductus arteriosus; RSS, Respiratory Severity Score