Objective: Elevated pulmonary vascular resistance and poor ventilation-perfusion matching are commonly found in preterm infants with severe respiratory distress syndrome (RDS) and respiratory failure. Inhaled nitric oxide (iNO) can improve gas exchange and decrease pulmonary vascular resistance. This study was conducted to determine whether iNO therapy improves oxygenation in such infants.Study Design: Between July 2000 and 2006, 65 preterm infants (birth weight, <1500 g; gestational age, <31 weeks) with severe RDS and respiratory failure requiring mechanical ventilation and an oxygenation index (OI)X25 were randomly divided into two groups. Group A infants (n ¼ 32) received iNO therapy. iNO was started at a dose of five parts per million (p.p.m.). The maximal dose of NO was 20 p.p.m. Group B infants (n ¼ 33) did not receive iNO therapy, receive inhaled oxygen placebo only, was served as control group. Mechanical ventilation and iNO therapy were managed by neonatologists who were not involved in safety monitoring, data analysis and interpretation, or manuscript preparation. This study was randomized but not blinded. Result:The OI was significantly lower (P<0.01) in the iNO therapy group than in the control group at 30 min, 3, 12 and 24 h after initiating iNO therapy. Six infants in the iNO-treated group and 10 infants in the control group died. Post hoc analyses did not reveal any significant differences in the incidences of chronic lung disease (CLD), intracranial hemorrhage (ICH), patent ductus arteriosus (PDA), retinopathy of prematurity (ROP) or duration of intubation between the iNO-treated and the control groups. Conclusion:We conclude that iNO therapy leads to an improvement in oxygenation without short-term side effects (such as pulmonary hemorrhage, intracranial hemorrhage, pneumothorax or acute deterioration) in premature infants with severe RDS and respiratory failure. However, iNO therapy does not significantly reduce mortality rate or the incidences of CLD, ICH, PDA or ROP.

The aim of this study was to establish the normal values and evaluate associated factors of gallbladder volume and contractility in term and preterm neonates by using ultrasonography. Sonographic measurement of gallbladder volume was performed by using the ellipsoid method in 50 preterm and 46 term infants. We collected data soon after delivery and at 6‐h fasting, and at 3‐h and 6‐h fasting following regular milk feeding. Serial postprandial changes of gallbladder volume and contractility were collected at 15‐min intervals for one hour. Gallbladder contraction index (C.I.) was determined as percentage decrement of postprandial size from initial size. Fasting gallbladder volume was larger in term group (p < 0:05). Term neonates more readily showed significant contraction (C.I. > 50%;p < 0:05). In preterm infants significant contraction was clearly observed at postconceptional age > 31 weeks or body weight > 1300 g. The presence of hepatobiliary diseases might be detected by evaluating serial changes of gallbladder volume and contractility under ultrasonography in the neonatal stage.