Outcomes Of Initial Noninvasive Positive Pressure Ventilation In Muiti-center Very Preterm Infants

Objective:To analyze the outcomes of initial noninvasive positive pressure ventilation in very preterm infants after birth in Sina-northern Neonatal Network(SNN),so as to provide a basis for further improving the survival rate and quality of life of very preterm infants.Methods:Using a multi-center prospective observational cohort study,the perinatal data,clinical treatment and outcomes after birth of very preterm infants with gestational age<32 weeks born in 2019-2020 were prospectively collected from neonatal intensive care units of 23 third-class grade A hospital in SNN.According to the outcomes of noninvasive positive pressure ventilation,they were futher divided into failure group and success group.The differences in risk factors between the success group and the failure group were compared using the x2 test or the Fisher exact probability test and the non-parametric test.The risk factors with statistically significant differences were further analyzed by binary logistic regression.The outcomes were compared between the two groups with the x2 test or the Fisher exact probability test.P<0.05 was considered as statistically significant.Results:A total of 3,792 very preterm infants with gestational age<32 weeks were included in the study.After excluding 132 infants with incomplete respiratory management data,232 infants abandoning treatment,6 infants with severe congenital malformations,486 infants without requirement for respiratory support and 862 infants with initial invasive mechanical ventilation,a total of 2,074 infants receiving noninvasive positive pressure ventilation were enrolled finally.Among them,there were 1,147(55.3%)boys and 927(44.7%)girls;152(7.3%)infants had birth weight<1,000 g and 1,922(92.7%)had birth weight>1,000 g;105(5.1%)infants had gestational age of 25～27+6 weeks and 1,969(94.9%)infants had gestational age of 28～31+6 weeks;and 181(8.7%)infants in the failure group and 1,893(91.3%)infants in the success group.The failure rates of initial noninvasive positive pressure ventilation of the 25～27+6 weeks group and the 28～31+6 weeks group were 24.8%(26/105)and 7.9%(155/1,969),respectively.Multivariate logistic regression analysis showed that small gestational age,maternal pregnancy-induced hypertension,postnatal grade Ⅲ-Ⅳrespiratory distress syndrome(RDS),use of pulmonary surfactant(PS)≥2 times and inhaled oxygen concentration>0.30 were independent risk factors for the failure of initial noninvasive positive pressure ventilation(OR=0.678,1.628,2.283,4.402,3.920;95%CI:0.572～0.803,1.056～2.511,1.562～3.337,2.657～7.292,2.770～5.546;all P<0.05).Multivariate logistic regression analysis demonstrated that the mortality and the incidences of neonatal pulmonary hemorrhage,moderate and severe BPD,severe IVH and≥ stage 2 ROP in the failure group were significantly higher than those in the success group(OR=3.007,5.352,3.128,3.022,2.105;95%CI:1.299～6.964,2.993～9.571,1.821～5.374,1.024～8.924,1.325～3.344;all P<0.05).Conclusion:The risk factors for the failure of initial noninvasive positive pressure ventilation include the small gestational age of very preterm infants,maternal pregnancy-induced hypertension,grade Ⅲ-Ⅳ RDS after birth,PS use ≥2 times and inhaled oxygen concentration>0.30.The incidence of major adverse outcomes such as mortality of very preterm infants after failure of initial noninvasive positive pressure ventilation is high,and longer hospital stay and respiratory support.