Objective: To study the effect of bronchopulmonary dysplasia (BPD) on lung function in preterm infants.
Methods: According to the presence/absence or the severity of BPD, 72 preterm infants were divided into non-BPD group (n=44), mild BPD group (n=15) and moderate BPD group (n=13). Lung function was assessed by plethysmography on days 7, 14 and 28 after birth.
Results: The preterm infants in the three groups had gradual increases in tidal volume per kilogram (TV/kg), functional residual capacity (FRC), ratio of time to peak tidal expiratory flow to total expiratory time (%T-PF) and ratio of volume to peak tidal expiratory flow to total expiratory volume (%V-PF) on days 7, 14 and 28 after birth, while there were gradual reductions in effective airway resistance per kilogram (Reff/kg) and respiratory rate (RR) (P<0.05). Compared with the non-BPD group on days 7, 14 and 28 after birth, the mild and moderate BPD groups had significantly lower TV/kg, FRC, %T-PF, and %V-PF and significantly higher Reff/kg and RR (P<0.05). On day 7 after birth, the moderate BPD group had significantly higher airway resistance, Reff/kg and FRC/kg than the mild BPD group (P<0.05).
Conclusions: There is a certain degree of pulmonary function impairment in preterm infants with BPD. Dynamic monitoring of lung function by plethysmography is useful for assessing lung development in the neonatal period in these infants.
目的: 探讨支气管肺发育不良（BPD）对早产儿肺功能的影响。
方法: 根据是否发生BPD及BPD程度将72名早产儿分为3组：非BPD组（n=44）、轻度BPD组（n=15）、中度BPD组（n=13），采用体积描记术测定各组生后7 d、14 d及28 d的肺功能。
结果: 3组早产儿公斤体重潮气量（TV/kg）、功能残气量（FRC）、达峰时间比（% T-PF）、达峰容积比（% V-PF）在生后7 d、14 d及28 d均逐渐升高，而公斤体重气道阻力（Reff/kg）及呼吸频率（RR）则逐渐下降（P < 0.05）；轻度及中度BPD组在生后7 d、14 d、28 d的TV/kg、FRC、% T-PF、% V-PF均低于非BPD组，而Reff/kg及RR则高于非BPD组（P < 0.05）；中度BPD组在生后7 d的气道阻力（Reff）、Reff/kg、公斤体重功能残气量（FRC/kg）高于轻度BPD组（P < 0.05）。
结论: BPD患儿存在一定程度的肺功能受损；体积描记肺功能监测有助于评估BPD患儿在新生儿期的肺发育。