探讨极低出生体重儿(VLBWI)/超低出生体重儿(ELBWI)的临床特点、救治策略及转归，为VLBWI/ELBWI的临床救治提供参考。

选取2009年1月1日至2015年12月31日于四川大学华西第二医院新生儿科接受住院治疗的1 146例VLBWI/ELBWI为研究对象。将其按照胎龄分为：<28周组(n＝84)、≥28～32周组(n＝679)、≥32～37周组(n＝378)及≥37周组(n＝5)。分析各组VLBWI/ELBWI的临床特点，统计学比较各组受试者住院时间、存活率、呼吸机使用情况、主要并发症发生情况、放弃治疗情况等。

本研究纳入的1 146例VLBWI/ELBWI中，早产儿为1 141例，足月儿为5例，由于足月儿中VLBWI/ELBWI病例数太少，故未对其进行相关统计学分析。对于<28周组、≥28～32周组、≥32～37周组VLBWI/ELBWI进行统计学比较的结果显示：①3组受试者住院时间、存活率比较，差异有统计学意义(Z＝34.667，P<0.001；χ²＝71.012，P<0.001)，并且VLBWI/ELBWI胎龄越小，住院时间越长，存活率越低。②<28周组VLBWI/ELBWI的有创机械通气治疗率，显著高于≥28～32周组及≥32～37周组，并且差异均有统计学意义(χ²＝53.001、162.157，P<0.001)。<28周组及≥28～32周组无创辅助通气治疗率，均显著高于≥32～37周组，并且差异均有统计学意义(χ²＝21.872、74.418，P<0.001)，但是，<28周组与≥28～32周组呼吸暂停和宫内感染发生率分别比较，差异均无统计学意义(P>0.05)。3组无创辅助通气治疗时间两两比较，差异均有统计学意义(Z＝－4.077，P<0.001；Z＝－4.655，P<0.001；Z＝－2.879，P＝0.002)，并且胎龄越小，无创辅助通气治疗时间越高。③3组VLBWI/ELBWI常见并发症，如新生儿呼吸窘迫综合征(NRDS)、严重颅内出血(Ⅲ～Ⅳ级)、支气管肺发育不良(BPD)及早产儿视网膜病变(ROP)发生率分别比较，差异均有统计学意义(χ²＝111.662、74.639、58.076、70.049，P<0.001)，并且胎龄越小，上述并发症发生率越高。3组呼吸暂停与宫内感染发生率分别比较，差异均有统计学意义(χ²＝59.683、25.937，P<0.001)；而<28周组及≥28～32周组呼吸暂停及宫内感染发生率，均显著高于≥32～37周组，差异均有统计学意义(χ²＝19.586、57.893，P<0.001；χ²＝10.146、25.019，P<0.001)，但是<28周组分别与≥28～32周组呼吸暂停和宫内感染发生率比较，差异均无统计学意义(P>0.05)。④3组VLBWI/ELBWI放弃治疗率比较，差异有统计学意义(χ²＝18.636，P<0.001)，并且胎龄越小，放弃治疗率越高；死亡VLBWI/ELBWI中，放弃治疗后死亡者占73.8%(141/191)。

VLBWI/ELBWI中，胎龄越小，并发症发生率越高，呼吸机治疗率及治疗时间明显增加，VLBWI/ELBWI存活率下降。降低VLBWI/ELBWI放弃治疗率，可提高其存活率。

To study the clinical characteristics, treatment strategies and outcomes of very low birth weight infants (VLBWI) and extremely low birth weight infants (ELBWI), and to provide references for the treatment of them.

From of 1 January 2009 to 31 December 2015, a total of 1 146 cases of VLBWI/ELBWI who were hospitalized in Department of Neonatology, West China Second University Hospital, Sichuan University were recruited as research subjects. According to the gestational ages, the VLBWI/ELBWI were divided into 4 groups: <28 weeks group (n=84), and ≥28-32 weeks group (n=679), ≥32-37 weeks group (n=378), ≥37 weeks group (n=5). The clinical characteristics of each group were analyzed, and hospitalization time, survival rate, rate of using ventilator, rate of the main complications, and the situation of giving up treatment were statistically compared among groups.

Among 1 146 cases of VLBWI/ELBWI, there were 1 141 premature infants and 5 full-term infants. Because the number of full-term infants was too small, they were not analyzed by statistical methods, <28 weeks, ≥28-32 weeks, ≥32-37 weeks group were compared by related statistical methods. The results showed as follows. ①There were significant differences among 3 groups in hospitalization time and survival rate (Z=34.667, P<0.001; χ²=71.012, P<0.001). And the smaller of gestational age, the longer of hospitalization time, the lower of survival rate among those 3 groups. ②Rates of using invasive ventilation in <28 weeks group were higher than those in ≥28-32 weeks group and ≥32-37 weeks group, and both the differences were statistically significant (χ²=53.001, 162.157; P<0.001). Rate of using noninvasive assisted ventilation in <28 weeks group and ≥28-32 weeks group were higher than those in ≥32-37 weeks group, and both the differences were statistically significant (χ²=21.872, 74.418; P<0.001), but there was no significant difference between <28 weeks group and ≥28-32 weeks group in the rates of using noninvasive assisted ventilation (P>0.05). There were significant differences in durations of noninvasive assisted ventilation treatment among 3 groups by pairwise comparison (Z=-4.077, P<0.001; Z=-4.655, P<0.001; Z=-2.879, P=0.002), and the smaller of gestational age, the longer duration of noninvasive assisted ventilation treatment. ③There were significant differences among common complications, such as neonatal respiratory distress syndrome (NRDS), severe intracranial hemorrhage (Ⅲ-Ⅳ), bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP) in 3 groups (χ²=111.662, 74.639, 58.076, 70.049; P<0.001), and the smaller gestational age, the higher incidences of aboved complications among 3 groups. There were significant differences in the incidences of apnea and intrauterine infection in 3 groups (χ²=59.683, P<0.001; χ²=25.937, P<0.001), and the incidences of apnea and intrauterine infection in <28 weeks group and ≥28-32 weeks group were higher than those in ≥32-37 weeks group, and all the differences were statistically significant (χ²=19.586, 57.893, P<0.001; χ²=10.146, 25.019, P<0.001), but there were no significant differences between <28 weeks group and ≥28-32 weeks group in the incidences of apnea or intrauterine infection (P>0.05). ④There were significant difference in 3 groups of rates of abandoned treatment (χ²=18.636, P<0.01). The smaller gestational age, the higher rate of abandoned treatment among 3 groups. Among the dead of VLBWI/ELBWI, the percentage of death after abandoned treatment was 73.8% (141/191).

In the VLBWI/ELBWI, the smaller gestational age, the higher rate of complications, higher use rates and longer use time of ventilations, and the lower survival rate. Reducing the proportion of abandoned treatment can improve the survival rate of VLBWI/ELBWI.