目的 探讨早产儿支气管肺发育不良（BPD）严重程度的影响因素。方法 收集2011 年1 月至2013 年12 月住院28 d 以上的明确诊断为BPD 的早产儿110 例，根据临床分度标准分为轻度BPD（52 例）、中度BPD（44 例）、重度BPD（14 例），探讨不同分度BPD 与出生胎龄、出生体重、窒息、吸氧、母亲妊娠并发症、宫内感染性肺炎及机械通气等因素的关系。结果 不同分度BPD 与出生胎龄、出生体重、母亲产前感染、吸氧浓度>40% 的持续时间、是否机械通气、机械通气参数、机械通气时间、持续气道正压通气（CPAP）时间、是否采用INSURE 模式及是否合并解脲脲原体感染、宫内感染性肺炎及动脉导管未闭有关。有序logistic 回归分析显示机械通气参数中的吸气峰压（OR=1.260，95%CI：1.096~1.448）、机械通气时间（OR=1.010，95%CI：1.005~1.016）为BPD 严重程度的独立危险因素，采用INSURE 模式为保护因素（OR=0.208，95%CI：0.060~0.923）。结论 早产儿BPD 严重程度与多种因素有关；避免低出生体重早产儿出生、缩短应用机械通气时间、防止和减少肺部感染以及尽量采用INSURE 技术是预防BPD 进展的重要措施。

Objective To explore the influencing factors for the severity of bronchopulmonary dysplasia (BPD) in preterm infants. Methods The clinical data of 110 preterm infants who were diagnosed with BPD and had a hospital stay of over 28 days between January 2011 and December 2013 were analyzed. These BPD infants were divided into 3 groups according to the clinical criteria: mild group (n=52), moderate group (n=44), and severe group (n=14). The relationship between the severity of BPD and the gestational age, birth weight, asphyxia, oxygen therapy, pregnancy complications, intrauterine pneumonia and mechanical ventilation was analyzed. Results The severity of BPD was correlated with the following factors: gestational age, birth weight, prenatal infection, duration of oxygen inhalation with a concentration of >40%, use of mechanical ventilation, parameters and duration of mechanical ventilation, duration of continuous positive airway pressure, adoption of intubation surfactant extubation (INSURE) approach, Ureaplasma urealyticum infection, intrauterine pneumonia and patent ductus arteriosus. Logistic regression analysis indicated that the mechanical ventilator parameter peak inspiratory pressure (OR=1.260, 95%CI: 1.096-1.448) and duration of mechanical ventilation (OR=1.010, 95%CI: 1.005-1.016) were independent risk factors for the severity of BPD, while the INSURE approach was a protective factor (OR=0.208, 95%CI: 0.060-0.923). Conclusions The severity of BPD is associated with various factors in preterm infants. The important measures for preventing BPD include avoiding the birth of preterm infants with a very low birth weight, shortening the duration of mechanical ventilation, preventing and reducing pulmonary infections, and applying the INSURE approach.