Effect of NO inhalation on ECMO use rate and mortality in infants born at or near term with respiratory failure

BACKGROUND: The molecular studies showed that Nitric oxide (NO) is an essential factor which regulates pulmonary artery tension. However, the conclusions of existing clinical studies were inconsistent. OBJECTIVE: This meta-analysis is aimed to determine whether the inhalation of NO could improve oxygenation and reduce rate of death and use of extracorporeal membrane oxygenation (ECMO). METHODS: The strategies used to search PubMed, The Cochrane Central Register of Controlled trials in the Cochrane Library, Embase, Web of science, Clinical Trials Registry, and China Biology Medicine disc, from inception to February, 2018. The primary outcomes were death or use of ECMO, death before hospital discharge, use of ECMO before hospital discharge, change in PaO2 after treatment. We assess the risk of bias in each included study by Cochrane Handbook, and calculated typical estimates of RR, each with its 95% CI, and for continuous outcomes, WMD or a summary estimate for SMD, each with its 95% CI. RESULTS: Nine randomized controlled trials (RCTs) with a total of 856 participants were included in this meta-analysis. This meta-analysis revealed that the experimental group had significantly lower death or use of ECMO (RR 0.66, 95% CI 0.57–0.77, I(2) = 0%, P < .00001) and lower use of ECMO before hospital discharge (RR 0.89, 95% CI 0.50–0.71, I(2) = 0%, P < .00001) compared to control group. And in the infants without diaphragmatic hernia, experimental group had significantly higher change in PaO2 after treatment (MD 50.40, 95% CI 32.14–68.66, P < .00001). The meta-analysis also showing a tendency to improve in the death before hospital discharge (RR 0.89, 95% CI 0.60–1.31, I(2) = 0%, P = .55) and the change in PaO2 after treatment of the infants with diaphragmatic hernia (MD 6.70, 95% CI −2.32 to 15.72, P < .00001, P = .15), but no difference between experimental group and control group. CONCLUSION: We found that NO inhalation can improve oxygenation and reduce rate of death and use of ECMO in this meta-analysis. Therefore, we recommend the use of NO inhalation for infants born at or near term with respiratory failure.