Clinical Analysis Of Respiratory Distress Syndrome(RDS) In Neonates Among Different Gestational Ages

Background:Although with the rapid development of use of pulmonary surfactant and mechanical ventilation in neonatal intensive care technology,the case fatality rate of neonatal respiratory distress syndrome(NRDS)has declined,but it is still the most common respiratory diseases in NICU,mostly in premature infants,and the rate of onset is higher when smaller the gestational age.In recent years,some studies have pointed out that the incidence of RDS in full-term or near term infants has increased significantly,which may be related to the increase of elective cesarean section rate.The risk factors,clinical manifestations,treatment and complications of full-term or near term infants with RDS are significantly different from those of premature infants.Therefore,it is necessary to carry out further studies to guide the clinical prevention and treatment.Objective:This study was designed to compare cases according to different gestational ages 1)To provide a new basis for clinical therapy through investigate the different clinical characteristics and incidence of early preterm infants,late preterm infants and full-term infants with RDS;2)To understand the relevance between different risk factors,clinical features and treatment effects of Respiratory Distress Syndrome(RDS)at different gestational ages such as early preterm(<34weeks of gestation),late preterm(34-36+6weeks of gestation)and full-term infants(? 37 weeks of gestation)admitted to neonatal care intensive unit(NICU)and to provide the basis for assessing the curative effect and prognosis.Materials and Methods:1.Objects and grouping:All case records of 524 neonates with final diagnosis of NRDS were retrospectively analyzed who had been admitted to NICU of Zhongda Hospital affiliated to Southeast University from January 2011 to December 2014.These cases were divided into three groups according to gestational age,which included early preterm infants group(<34weeks,228 cases),late preterm infants group(34?36+6weeks,162 cases)and full-term infants group(? 37 weeks,134 cases).2.Methods:All of the 524 RDS cases with different gestational ages were analyzed by the following aspects:(1)Incidence:The percentage of preterm infants and RDS cases in all NICU patients,the constituent ratio of RDS infants with different gestational age in each year;(2)General situation:including gender,Apgar score(1min,5min),birth weight,gestational and maternal age,antenatal corticosteroids usage before delivery and length of hospitalization;(3)Risk factors:elective cesarean section,intrauterine distress,birth asphyxia,premature rupture of membranes,placenta and amniotic fluid abnormality,twins,maternal diseases in pregnancy;(4)Treatment:including the time and usage of CPAP,invasive ventilation(CMV/HFOV)and the application and repeated doses of pulmonary surfactant(PS);(5)Complications:Pneumonia,sepsis,pneumothorax,ICH,HIE,ROP,BPD,CHD,jaundice,anemia,hypothyroidism,etc.(6)Prognosis:including treatment outcome such as improve or cure,abandonment and mortality.3.Statistical analysis:All statistical data were analyzed by SPSS 20.0 software,quantitative data were presented as mean ± standard deviation(x± s).One-way analysis of variance analysis was used to compare the means during groups.Qualitative data were presented as rate(%)and compared with Chi-square test.P<0.05 was considered as statistically significant.Results:RDS mainly occurred in the preterm infants.The proportion of RDS infants in all admitted patients during the recent four years(2011-2014)was 13.1%,15.5%,8.6%and 11.6%respectively.The prevalence of RDS in early preterm infants was increasing every year.The proportion of RDS in male was higher than that in females,especially when the gestational ages and weight are greater in different groups.The proportion of antenatal corticosteroids and length of hospitalization was higher among the early preterm infants group(p<0.05)than the other two groups.In this study,with the comparison of risk factors among the three different gestational groups of neonates with RDS,elective cesarean section,intrauterine distress,twins or triplets,PROM,amniotic fluid abnormalities showed statistically significant difference(P<0.05)between three groups.The incidence of Cesarean section was high among the three groups,especially the full-term(78.4%)and late preterm group(72.2%).The risk factors of preterm RDS were closely relevant to the birth asphyxia,PROM,placental abnormality,women with pregnancy-induced hypertension,twins and while the full-term newborns with RDS were mainly related to elective cesarean section,infection and male gender.The proportion of PS application and repeated administration in early preterm group was higher and showed significant difference(P<0.05).The treatment with conventional mechanical ventilation in full-term RDS infants was significantly higher than that in the preterm infants,but with more pneumonia,PPHN,HIE and pneumothorax occurred(p<0.05).Early preterm infants group had higher rates of ICH,ROP,sepsis,jaundice,anemia,hypothyroidism and mortality rate than other two groups.No significant differences were found in pulmonary hemorrhage,bronchopulmonary dysplasia,PDA and abandonment rate between groups.Conclusion:Neonatal RDS predominantly occurred in the preterm infants.The risk factors,complications,treatment and prognosis of RDS in neonates among three groups were different,so gestational ages should be considered for diagnosis and treatment.The common risk factors of full-term infants were elective cesarean section,infection and male gender,so the elective caesarean section should be strictly controlled,in order to reduce the incidence of RDS.