Abstract: 【Abstract】 Objective To study the survival rate, incidence of complications and the risk factors affecting clinical outcomes for extremely preterm infants(EPI). Methods The clinical data of 311 cases of EPI discharged from department of neonatology, the Third Affiliated Hospital of Guangzhou Medical University from January 1, 2008 to December 31, 2017 were analyzed by retrospective analysis. The survival rate, mortality rate and incidence of complications were compared according to gestationalage(GA), birth weight(BW) and the year of discharge. Multivariate unconditional Logistic regression analysis was used to analyze the risk factors affecting EPI survival rate. Results In the 311 EPI, the average GA was (26.6±1.0) weeks and average BW was (923 ± 180)g, 117 (37.6%) infants survived, 38 (12.2%) infants died of treatment failure, and 156 (50.2%) infants died after giving up treatment for various reasons. There were no significant differences in composition ratio or overall survival rate for EPI ( GA=26 weeks, 26-26+6 weeks, 27-27+6 weeks or BW<750 g, 750-999 g, ≥ 1 000 g) between
2013-2017 and 2008-2012(P>0.05). However, there were significant differences in mortality of treatment failure, mortality of abandon treatment, and corrected survival rate( P<0.001). The survival rates of GA<26 weeks, 26-26+6 weeks, 27-27+6 weeks were 17.6% (12/68), 32.6% (30/92), and 49.7% (75/151), respectively. There were statistical significant differences among these groups (χ2=21.885，P<0.001). Similarly, the survival rates of BW<750 g, 750-999 g, and ≥ 1 000 g groups were 16.7%
(8/48), 35.8% (58/162), and 50.5% (51/101), respectively. There were statistical differences among these groups ( χ2= 16.342, P<0.001). The incidence of the top five complications in EPI was 92.0% (286/311)for neonatal respiratory distress syndrome, 81.3% (100/123) for bronchopulmonary dysplasia, 59.5%(78/131) for retinopathy of prematurity, 49.5% (107/216) for nosocomial infection, 44.1% (71/161) forperiventricular-intraventricular hemorrhage. Multivariate unconditional Logistic regression analysis showed that the independent risk factors affecting EPI survival were GA<27 weeks (GA<26weeks,
OR=3.122, 95%CI 1.443-6.752, P=0.004; 26-26+6 weeks, OR=1.834, 95%CI 1.035-3.250, P=0.038), BW<750 g(OR=2.769, 95%CI 1.078-7.109, P=0.034), asphyxia(OR=2.566, 95%CI 1.241-5.302, P=0.011) andpulmonary hemorrhage(OR=2.188, 95%CI 1.155-4.145, P=0.016), while the protective factor was antenatal corticosteroids(OR=0.449, 95%CI 0.244-0.827, P=0.010). Conclusions In China, the survival rate of EPI is still low while the rate of abandoning treatment is high, and the survival rate increase with the increase of gestational age. The independent risk factors affecting the survival of EPI treatment are GA<27 weeks,BW<750 g, asphyxia and pulmonary hemorrhage. The protective factor is antenatal corticosteroids.
2020, Vol. 8 
