Analysis Of Risk Factors And Short-term Clinical Outcome Of Bronchopulmonary Dysplasia Complicated With Pulmonary Hypertension In Premature Infants

Objective: Pulmonary hypertension(PH)is a serious complication of bronchopulmonary dysplasia(BPD)in premature infants,and it is also an important factor leading to high mortality and adverse outcome of BPD,but the risk factors of BPD-PH are not completely clear.The purpose of this study is to explore the risk factors and short-term clinical outcome of BPD complicated with PH in premature infants,in order to provide reference for clinical management,diagnosis,treatment and prevention of BPD-PH.Methods: This is a retrospective case-control study,and a total of 85 infants with BPD whose gestational age was less than 32 weeks were selected from the first Neonatal Ward of Shengjing Hospital affiliated to China Medical University from January 2021 to December 2022.(1)According to the grading criteria of BPD,85 premature infants with BPD were divided into mild BPD group,moderate BPD group and severe BPD group.According to the elevated pulmonary artery pressure confirmed by echocardiography at 36 weeks of gestational age,the incidence of PH in the three groups was statistically analyzed.(2)85 premature infants with BPD were divided into BPD plus PH group(BPD-PH)and BPD without PH group(BPD-non-PH).Statistics were made on the general data,perinatal data,clinical treatment and related diseases of premature infants of the two groups.Univariate analysis was carried out at first,and then all the statistically significant differences in univariate analysis were incorporated into multivariate Logistic regression to identify the independent risk factors of BPD-PH.The hospitalization time,hospitalization expenses and family oxygen therapy of the two groups were analyzed in order to compare the short-term clinical outcome of the two groups.Results:(1)Among the 85 cases of BPD,there were 53 cases(62%)in mild BPD group,17 cases(20%)in moderate BPD group and 15 cases(18%)in severe BPD group.The incidence of PH was 9 cases(17%),8 cases(47%)and9 cases(60%)in mild BPD group,moderate and severe BPD group,respectively.The incidence of PH in moderate and severe BPD was significantly higher than that in mild BPD.The incidence of PH in all BPD children was 31%.(2)59 cases(69%)in BPD-non-PH group and 26 cases(31%)in BPD-PH group.Univariate analysis showed that compared with the BPD non-PH group,the BPD-PH group had longer time of invasive mechanical ventilation and oxygen inhalation,and higher proportion of retinopathy and septicemia of prematurity.Other factors include sex,gestational age,birth weight,advanced parturient,gestational diabetes,pregnancy induced hypertension,prenatal use of hormones,mode of delivery,twins / multiple births,abnormal placenta(including placenta previa,placental abruption),premature rupture of membranes,oligohydramnios,meconium stained amniotic fluid,small gestational age infants,1-minute and5-minute Apgar scores,maximum FiO2 ≥ 40% within 6 hours after birth,non-invasive ventilation time,PS use ≥ 2 times,There was no significant difference in neonatal respiratory distress syndrome,patent ductus arteriosus,neonatal necrotizing enterocolitis,intracranial hemorrhage,white matter injury,metabolic bone disease,neonatal cholestasis,gastroesophageal reflux disease and Ureaplasma Urealyticum infection between the two groups(P >0.05).The results of Logistic regression analysis showed that long-time invasive mechanical ventilation was an independent risk factor for BPD complicated with PH(OR=1.003,95%CI:1.000-1.005,P=0.037).Compared with BPD non-PH group,BPD-PH group had longer hospitalization time,higher hospitalization cost and higher proportion of home oxygen therapy.Conclusion:(1)In BPD,moderate to severe BPD is more likely to be complicated with PH,and long-time invasive mechanical ventilation is an independent risk factor for BPD-PH.(2)BPD combined with PH can prolong hospital stay and increase hospitalization costs,and children with BPD-PH are more likely to need home oxygen therapy.(3)For children with moderate to severe BPD and those who can not leave the machine for a long time,we should be highly vigilant against the occurrence of PH.