目的 探讨不同程度支气管肺发育不良（BPD）早产儿的临床特点及预后。方法 收集2014年3月至2016年3月入住NICU诊断为BPD且胎龄 < 32周的144例早产儿的临床资料，其中轻度组81例，中重度组63例，对轻度组与中重度组围生期高危因素及治疗情况、合并症及并发症、呼吸系统预后等情况进行比较和分析。结果 中重度组胎龄大于轻度组（P < 0.05），但小于胎龄儿比例高于轻度组（P < 0.05）。中重度组重度子癎前期比例高于轻度组（P < 0.05），先兆早产比例低于轻度组（P < 0.05）。中重度组生后2周仍需机械通气比例、机械通气时间、总氧疗时间、住院时间、肺炎及胆汁淤积综合症发生率高于轻度组（均P < 0.05），枸橼酸咖啡因应用率低于轻度组（P < 0.05）。多因素logistic回归分析显示，小于胎龄儿（OR=5.974）、肺炎（OR=2.590）、出生2周仍需机械通气（OR=4.632）是BPD程度较重的危险因素（P < 0.05）。纠正胎龄40周肺功能检测中，中重度组达峰时间比（TPTEF/TE%）、达峰容积比（VPEF/VE%）及25%潮气量时呼吸流速（TEF25%）均低于轻度组（P < 0.05）。随访至纠正胎龄1岁，中重度组因肺炎反复入院率及喘息发作率均高于轻度组（P < 0.05）。结论 小于胎龄儿、肺炎、机械通气时间较长与BPD的严重程度相关，可加重BPD程度。中重度BPD患儿肺功能较差，易出现反复感染、喘息等并发症，应关注其远期预后。

Objective To study the clinical features and prognosis of preterm infants with varying degrees of bronchopulmonary dysplasia (BPD). Methods The clinical data of 144 preterm infants with a gestational age of < 32 weeks who were admitted to the neonatal intensive care unit from March 2014 to March 2016 and were diagnosed with BPD were collected. According to the severity of BPD, these preterm infants were divided into mild group with 81 infants and moderate/severe group with 63 infants. The two groups were compared in terms of perinatal risk factors, treatment, comorbidities, complications, and prognosis of the respiratory system. Results Compared with the mild BPD group, the moderate/severe BPD group had a significantly higher gestational age and rate of small-for-gestational-age (SGA) infants (P < 0.05), as well as a significantly higher rate of severe preeclampsia and a significantly lower rate of threatened preterm labor (P < 0.05). Compared with the mild BPD group, the moderate/severe BPD group had a significantly higher percentage of infants who needed mechanical ventilation at 2 weeks after birth, longer duration of mechanical ventilation, total time of oxygen therapy, and length of hospital stay, and higher incidence rates of pneumonia and cholestasis (P < 0.05), as well as a significantly lower application rate of caffeine citrate (P < 0.05). The multivariate logistic regression analysis showed that SGA birth (OR=5.974, P < 0.05), pneumonia (OR=2.590, P < 0.05), and mechanical ventilation required at 2 weeks after birth (OR=4.632, P < 0.05) were risk factors for increased severity of BPD. The pulmonary function test performed at the corrected gestational age of 40 weeks showed that compared with the mild BPD group, the moderate/severe BPD group had significantly lower ratio of time to peak tidal expiratory flow to total expiratory time, ratio of volume to peak tidal expiratory flow to total expiratory volume, and tidal expiratory flow at 25% remaining expiration (P < 0.05). The infants were followed up to the corrected gestational age of 1 year, and the moderate/severe BPD group had significantly higher incidence rates of recurrent hospital admission for pneumonia and recurrent wheezing (P < 0.05). Conclusions SGA birth, pneumonia, and prolonged mechanical ventilation are associated with increased severity of BPD. Infants with moderate or severe BPD have poor pulmonary function and may experience recurrent infection and wheezing.