Exhaled ntric xxide in nonates wth and wthout hypoxemic respiratory failure / 中华急诊医学杂志

ABSTRACT

ObjectiveTo establish a method for measuring exhaled nitric oxide (eNO)concentrations in neonates with and without hypoxemic respiratory failure ( HRF), and to investigate the relationship between eNO and respiratory parameters in neonates with HRF. Methods Twenty-two newborn infants with HRF and 26 control neonates were included within the first 24 hours of postnatal life.Their eNO levels were detected with a rapid-response chemiluminescence analyzer daily during the first week of their postnatal life, and lung mechanics and gas exchange efficiency were monitored at the same time, such as pulse oxygen saturation ( SpO2 ), inspired fraction of oxygen ( FiO2 ) and other parameters.Wilcoxon Mann-Whitney U tests were used to compare eNO, SpO2/FiO2 and eNO/ ( SpO2/FiO2 × 100) in two groups. Pearson's correlation analyses were used to determine the relationships between eNO levels and indices of hypoxemic respiratory failure. ResultsDuring the first two days of postnatal life, eNO values of HRF neonates were higher than those of the control neonates[day 1,(7. 9 ± 3.2 )× 10-9 vs. (5.8 ±1.8)×10-9, P＜0.05;day2, (8.8±3.2)×10-9vs. (6.0±2.4)×10-9, P＜0. 05], butthere were no significant differences in the following days. With SpO2/FiO2 increasing, difference of eNO values between the HRF and non-HRF controls became narrowed, but there was still two fold difference of eNO/(SpO2/FiO2 × 100) on day 5-7. ConclusionsA method for measuring eNO was established and there was difference in neonates with and without HRF, which diminished with prolonged postnatal days, reflecting pathophysiological characteristics of HRF.