生后院际转运时间对极早产儿临床特征及出院结局的影响

Clinical features and outcomes at discharge of outborn very preterm infants of different ages after interhospital transfer

目的分析国内院际转运极早产儿日龄分布情况,总结不同日龄转运极早产儿的围产期特征、出院结局以及住院期间治疗情况的差异。方法回顾性纳入2019年全年中国新生儿协作网(Chinese Neonatal Network,CHNN)极早产儿队列中胎龄24~31周^(+6)、在外院出生后转入CHNN新生儿重症监护病房(neonatal intensive care unit,NICU)救治的、排除严重先天畸形的极早产儿3405例。按照转运进入CHNN NICU的日龄分为早期转运组(≤1 d)、延迟转运组(>1~7 d)和晚期转运组(>7 d)。采用方差分析、t检验、χ^(2)检验(两两比较采用Bonferroni校正)、Kruskal-Wallis检验及Wilcoxon秩和检验比较3组极早产儿的一般临床情况、治疗情况及出院结局的差异。结果3405例极早产儿的中位胎龄为29.7周(28.3~31.0周),平均出生体重为(1321.0±316.5)g。早期转运组2031例(59.6%),延迟转运组406例(11.9%),晚期转运组968例(28.4%)。转运极早产儿产房内接受持续气道正压通气的比例为8.4%(237/2806),产房内气管插管比例为32.9%(924/2805)。共62.7%(1569/2504)的患儿母亲接受产前糖皮质激素治疗,早期转运组接受产前糖皮质激素治疗的比例为68.7%(1121/1631),高于延迟转运组[56.1%(152/271),χ^(2)=16.78,P<0.017]和晚期转运组[49.2%(296/602),χ^(2)=72.56,P<0.017]。转运极早产儿总死亡率为12.7%(431/3405),其中早期、延迟及晚期转运组患儿的死亡率分别为12.4%(252/2031)、16.3%(66/406)和11.7%(113/968),组间差异无统计学意义(χ^(2)=5.72,P=0.057)。延迟转运组和晚期转运组患儿重度脑室内出血、晚发型败血症、新生儿坏死性小肠结肠炎和纠正胎龄36周或出院时支气管肺发育不良的发生率高于早期转运组,晚期转运组患儿早产儿视网膜病变、接受治疗的早产儿视网膜病变和纠正胎龄36周或出院时支气管肺发育不良的发生率高于延迟转运组,差异均有统计学意义(Bonferroni校正法,P值均<0.017)。晚期转运组极早产儿出院日龄为66.0 d(51.0~86.0 d),出院纠正胎龄为38.9周(37.1~41.2周),均大于早期转运组[48.0 d(37.0~64.0 d),Z=260.83;36.9周(35.7~38.3周),Z=294.32]和延迟转运组患儿[52.0 d(41.0~64.0 d),Z=81.49;37.4周(36.1~38.7周),Z=75.97],差异均有统计学意义(P值均<0.017)。结论目前国内仍有大量极早产儿需要生后转院。转运日龄越晚、极早产儿并发症发生率越高。故建议可能发生极早产的孕妇宫内转运或生后尽早转运,可能有助于改善预后。

Objective To analyze the distribution of ages at the interhospital transfer of outborn very preterm infants in China and to compare their perinatal characteristics and outcomes at discharge and neonatal intensive care unit(NICU)treatment.Methods A total of 3405 outborn very premature infants with a gestational age of 24-31^(+6) weeks who were transferred to the NICUs of the Chinese Neonatal Network(CHNN)in 2019 were included in this retrospective study.According to the age at transfer,they were divided into three groups:early transfer(≤1 d),delayed transfer(>1-7 d)and late transfer(>7 d)groups.Analysis of variance,t-test,Chi-square test(Bonferroni correction),Kruskal-Wallis test and Wilcoxon rank-sum test were used to compare the general clinical condition,treatment,and outcomes at discharge among the three groups.Results The median gestational age was 29.7 weeks(28.3-31.0 weeks)and the average birth weight was(1321.0±316.5)g for these 3405 infants.There were 2031 patients(59.6%)in the early transfer group,406(11.9%)in the delayed transfer group and 968(28.4%)in the late transfer group.Infants who received continuous positive airway pressure ventilation and tracheal intubation in the delivery room accounted for 8.4%(237/2806)and 32.9%(924/2805),respectively.A total of 62.7%(1569/2504)of the mothers received antenatal glucocorticoid therapy and the ratio in the early transfer group was 68.7%(1121/1631),which was higher than that in the delayed transfer group[56.1%(152/271),χ^(2)=16.78,P<0.017]and the late transfer group[49.2%(296/602),χ^(2)=72.56,P<0.017].The total mortality rate of very premature infants was 12.7%(431/3405),and the mortality rates in the early,delayed and late transfer groups were 12.4%(252/2031),16.3%(66/406)and 11.7%(113/968),respectively(χ^(2)=5.72,P=0.057).The incidences of severe intraventricular hemorrhage,late-onset sepsis,necrotizing enterocolitis,and bronchopulmonary dysplasia at the corrected gestational age of 36 weeks or discharge were all higher in the delayed and late transfer groups than in the early transfer group,respectively.The incidences of retinopathy of prematurity,retinopathy of prematurity requiring treatment and bronchopulmonary dysplasia at the corrected gestational age of 36 weeks or discharge in the late transfer group were significantly higher than that in the delayed transfer group(Bonferroni correction,all P<0.017).In the late transfer group,the median age of very premature infants at discharge was 66.0 d(51.0-86.0 d),and the corrected gestational age at discharge was 38.9 weeks(37.1-41.2 weeks),and both were greater than those in the early transfer[48.0 d(37.0-64.0 d),Z=260.83;36.9 weeks(35.7-38.3 weeks),Z=294.32]and delayed transfer groups[52.0 d(41.0-64.0 d),Z=81.49;37.4 weeks(36.1-38.7 weeks),Z=75.97](all P<0.017).Conclusions Many very premature infants need to be transferred to higher-level hospitals after birth.The later the very premature infants are transferred,the higher the incidence of complications will be.It is suggested that intrauterine or early postnatal transport may improve the prognosis of very premature infants.