Motoyama E K, Fort M D, Klesh K W, Mutich R L, Guthrie R D
Am Rev Respir Dis. 1987 Jul;136(1):50-7. doi: 10.1164/ajrccm/136.1.50.
Pulmonary function during the early development of bronchopulmonary dysplasia (BPD) in premature infants is not well understood. Furthermore, it is not known how early airway reactivity appears in BPD. During a 14-month period we studied 32 infants (mean gestational age, 27.3 wk; mean birth weight, 1.02 kg) with respiratory distress syndrome in whom BPD eventually developed. We obtained maximal expiratory flow-volume (MEFV) curves by manual inflation of the lung followed by forced deflation with a negative pressure on 64 occasions (mean postnatal age, 43.1 days). At each test MEFV curves were obtained in 3 conditions: baseline; after normal saline aerosolization with manual ventilation as a control; and after bronchodilator. Maximal expiratory flow at 25% of FVC (Vmax25) was markedly decreased at baseline and remained decreased after saline control. The FVC also was decreased in both baseline and saline control studies. After bronchodilator there was a marked (p less than 0.001) increase in Vmax25 (+214% above saline control) together with a significant (p less than 0.001) increase in FVC (+21%). Of 23 infants studied after 3 wk of postnatal age, 21 exhibited a more than 30% increase in Vmax25 above control (defined as airway reactivity). The remaining 2 infants were already receiving bronchodilator therapy. The most premature infant with demonstrable airway reactivity was 26 wk postconception, and the youngest was 12 days old. In 13 infants who were studied initially before 3 wk of age, there was a highly significant correlation (r = 0.91 p less than 0.001) between the degree of airway reactivity and the severity of respiratory disease as determined by the duration of ventilator dependence. Airway reactivity may play an important role in the development and severity of BPD.
早产儿支气管肺发育不良（BPD）早期的肺功能尚未完全明确。此外，BPD中气道反应性何时出现也不清楚。在14个月期间，我们研究了32例最终发展为BPD的呼吸窘迫综合征婴儿（平均胎龄27.3周；平均出生体重1.02千克）。我们通过手动给肺充气，然后在64次情况下（平均出生后年龄43.1天）用负压进行强制呼气，获得了最大呼气流量-容积（MEFV）曲线。每次测试时，在3种情况下获得MEFV曲线：基线；用手动通气进行生理盐水雾化后作为对照；以及使用支气管扩张剂后。在基线时，用力肺活量（FVC）25%时的最大呼气流量（Vmax25）显著降低，生理盐水对照后仍保持降低。在基线和生理盐水对照研究中，FVC也降低。使用支气管扩张剂后，Vmax25显著增加（比生理盐水对照增加214%，p<0.0)，FVC也显著增加（增加21%，p<0.001）。在出生后3周后研究的23例婴儿中，21例的Vmax25比对照增加超过30%（定义为气道反应性）。其余2例婴儿已经在接受支气管扩张剂治疗。具有可证实气道反应性的最早产婴儿是孕龄26周，最年幼的是12天。在最初于3周龄前进行研究的13例婴儿中，气道反应性程度与根据呼吸机依赖持续时间确定的呼吸系统疾病严重程度之间存在高度显著相关性（r = 0.91，p<0.001）。气道反应性可能在BPD的发生和严重程度中起重要作用。
