Table 1. Baseline characteristics of the enrolled infants.
| PPHN (N = 55) | non-PPHN (N = 57) | z/χ2 | P | |
|---|---|---|---|---|
| Male sex (%) | 31(56.36) | 36(63.16) | 0.538 | 0.463 |
| Gestational age (wk) | 37.58 ± 2.06 | 37.18 ± 2.05 | 1.197 | 0.232 |
| Birth weight (g) | 2986.1 ± 564.3 | 2880.6 ± 559.9 | 1.304 | 0.192 |
| Age at enrollment (d) | 2.4 ± 1.4 | 2.1 ± 0.9 | 0.782 | 0.434 |
| Cesarean section delivery (%) | 40(74.07) | 42(73.68) | 0.002 | 0.963 |
| Ventilation time (d)* | 5.4 ± 3.2 | 4.3 ± 3.9 | 3.333 | 0.001 |
| Maximal oxygenation index* | 22.335 ± 23.803 | 6.961 ± 4.078 | 6.169 | 0 |
| Inhaled nitric oxide (%)*Ψ | 25(45.5) | 0 | 33.354 | 0 |
| Vasoactive agents therapy (%)*Ψ | 528(50.91) | 1(1.75) | 35.246 | 0 |
| Mortality (%)Ψ | 5(9.1) | 1(1.75)) | 2.971 | 0.110 |
| Primary diagnosis*Ψ | ||||
| Hyaline membrane disease | 28 | 22 | 7.761 | 0.173 |
| Transient tachypnea of the newborn | 13 | 21 | ||
| Perinatal asphyxia | 9 | 8 | ||
| Meconium aspiration syndrome | 4 | 1 | ||
| Pneumothorax | 1 | 2 | ||
| Pneumonia | 0 | 3 | ||
*P < 0.05 for the comparison between groups. Ψχ2-Fisher’s Exact test.