Meta-analysis of inhaled nitric oxide in gestational age ≤34 weeks preterm infants / 中国新生儿科杂志

ABSTRACT

Objective:To evaluate the effect of inhaled nitric oxide (NO) in gestational age ≤34 weeks preterm infants using meta-analysis.Method:A search from PubMed, Embase, Cochrane Central library, China National Knowledge Internet, China biomedical literature database, Wanfang and VIP database from establishment to June 2020.Result:A total of 17 randomized controlled studies were included. The subjects were premature infants (gestational age ≤34 weeks) who needed respiratory support. The total sample size was 4 033.Meta-analysis showed that no significant difference was found in mortality between treatment and control groups ( RR=1.00, 95% CI 0.89~1.11, P=0.930).Risk of bronchopulmonary dysplasia (BPD) at 36 w postmenstrual age (PMA) was significantly lower in preterm infants supplemented with iNO ( RR=0.89, 95% CI 0.82~0.97, P=0.006). Subgroup analysis showed the overall risk of mortality or BPD incidence was significantly reduced for birth weight >1 000 g infants treated with iNO ( RR=0.72, 95% CI 0.58~0.89, P=0.002). Risk of BPD incidence was significantly lower when beginning iNO in the first 7 d of life ( RR=0.83, 95% CI 0.70~0.98, P=0.030). Risk of BPD incidence was significant reduced in infants treated with 5 ppm or ≥10 ppm iNO ( RR=0.89, 95% CI 0.81~0.98, P=0.020; RR=0.90, 95% CI 0.81~0.99, P=0.030). There was a decrease in BPD incidence with iNO treatment time of either ≤7 d or >7 d ( RR=0.77, 95% CI 0.60～0.99, P=0.040; RR=0.87, 95% CI 0.77~0.97, P=0.010). There were no differences concerning mechanical ventilation duration and intracranial hemorrhage incidence ( P>0.05). Significant difference was found between treatment and control group with respect to reduction of oxygenation index (OI) ( WMD=-6.32, 95% CI -12.16~-0.48, P=0.030). Conclusion:For preterm infants born at less than 34 weeks who need respiratory support, iNO treatment may improve oxygenation and reduce the risk of BPD, but not decrease mortality, mechanical ventilation duration or intracranial hemorrhage incidence. A better treatment effect may be achieved if iNO treatment began in the first 7 d of life, and if the infant had a birth weight greater than 1 000 g.