选择性剖宫产与足月儿呼吸窘迫综合征回顾性分析

Retrospective analysis of elective caesarean section and respiratory distress syndrome in the term neonates

目的探讨选择性剖宫产对足月儿呼吸窘迫综合征（RDS）发生的影响，并比较两中心足月儿RDS发生情况及相关影响因素。方法以2006年6月至2008年6月，在浙江大学附属儿童医院NICU及新生儿病房（A中心）和浙江大学附属妇产科医院NICU（B中心）收治的足月儿RDS为研究对象，分析选择性剖宫产RDS的胎龄分布、所有病例有并发症组与无并发症组的比较，以及两中心临床资料的分析比较。计数资料行x。检验，计量资料行t检验。结果90例足月儿RDS中88例为选择性剖宫产，占97．8％，39、40周以后的RDS构成比明显低于37周及38周时。经logistic回归分析，开始上机时间〉12h是足月儿RDS发生并发症的主要危险因素（DR=12．667，P=0．021）。两中心的病例在入院年龄（t=11．833，P=0．001）、胸部X线分期（X2=4．85，P=0．028）、PS应用（t=11．911，P=0．002）、开始上机时间（t=10．051，P=0．018）、上机前PaO2／FiO2（X2=4．184，P=0．005）、OI〉25（t=4．737，P=0．03）、用氧时间（X2=10．475，P=0．001）、并发低血压（t=11．020，P=0．01）以及住院时间（t=9．872，P=0．002）等均存在显著性差异。结论选择性剖宫产是足月儿RDS发生的重要影响因素，早期诊断、早期干预可以减少足月儿RDS的并发症。

Objective Severe respiratory distress syndrome （RDS） caused by pulmonary surfactant （PS） deficiency is described not only in preterm infants but also in term babies delivered via caesarean section, especially before the onset of labour （elective caesarean section）. Once RDS of term neonates happened, mechanical ventilation is needed, and the infants were at high risk of developing further complications such as persistent pulmonary hypertension of neonates （ PPHN ）, pulmonary air leak and cardiovascular instability, even fatal outcome cannot be avoided. The present study aimed to analyze the association between the elective caesarean section and respiratory distress syndrome （RDS） in term neonates, and to determine the related factors and outcomes of RDS cases in neonatal intensive care unit （NICU） and neonatology ward. Methods A retrospective study was conducted at the NICU and the Neonatology Ward of A center （ Children＇ s Hospital of Zhejiang University ） and the NICU of center B （Obstetrics and Gynecology Hospital of Zhejiang University） on 90 term infants who were diagnosed as RDS between June 2006 and June 2008. The general clinical data, mode of delivery, severity of the radiological sign, pulmonary surfactant （PS） application, the onset time and duration of mechanical ventilation, the ratio of PaO2 to FIO2 before mechanical ventilation, oxygenation index （OI）, duration of oxygen supplementation, the length of hospital stay and complications including pulmonary air leaks （pneumothorax, pulmonary interstitial emphysema）, PPHN, systemic hypotension and ventilator-associated pneumonia （VAP） were collected. The gestational age distribution was studied in RDS cases delivered by elective caesarean section, and the comparative analysis and non-conditional logistic regression analysis were performed for clinical characteristics and risk factors between the RDS cases with or without complications. P 〈 0. 05 was considered to be significant. Results There were 88 episodes of elective caesarean section in 90 RDS patients. The proportion of elective caesarean section was 97.8% （88/90）. The number of RDS cases was reduced gradually with the increase of gestational age and the constituent ratio of RDS at 39 w and at 40 w was significantly lower than that at 37 w and 38 w. By logistic regression analysis, the onset time of mechanical ventilation 〉 12 h independently predicted complications in RDS of term neonates （ odds ratio 12. 667, 95% confidence interval, i.e. , CI 1. 455 to 110. 300, P = 0. 021 ）. Moreover, there was a significant difference in the admission age （t = 11. 833, P = 0. 001 ） , severity of the radiological findings （ t = 4. 85, P = 0. 028 ）, PS application （ t = 11. 911, P = 0. 002 ）, the onset time of mechanical ventilation （t=10.051, P = 0.018）, the ratio of PaO2 to FIO2 before mechanical ventilation （X2 = 4. 184, P = 0. 005 ）, OI 〉 25 （t = 4. 737, P = 0. 03 ） , duration of oxygen supplementation （ X2 = 10. 475, P = 0. 001 ）, systemic hypotension （ t = 11. 020, P = 0. 01 ） and the length of hospital stay （ t = 9. 827, P = 0. 002 ） between the two centers. Conclusion Severe RDS can occur in term babies after elective caesarean section, gestational age at the time of elective caesarean section may also be important for RDS in term neonates. The onset time of mechanical ventilation 〉 12 h independently predicted complications in RDS of term neonates. The main complications of RDS in term neonates were PPHN, pulmonary air leaks and systemic hypotension. Early diagnosis, early intervention can significantly reduce the complications, alleviate the severity and shorten their time for oxygen therapy and their length of stay in NICU in term RDS infants.