Sandberg K, Edberg K E, Benton W, Silberberg A, Sladek M, Sundell H W
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
Pediatr Res. 1991 Aug;30(2):181-9. doi: 10.1203/00006450-199108000-00012.
Prophylactic treatment with ovine surfactant was evaluated in preterm lambs at risk for development of hyaline membrane disease. Eight mechanically ventilated newborn lambs were treated before delivery and 10 served as controls (gestational age 129-131 d). Lung mechanics, functional residual capacity, alveolar ventilation, efficiency of ventilation, and distribution of ventilation were tested using pressure, flow, and nitrogen elimination (nitrogen washout during 100% oxygen breathing) measurements in the endotracheal tube. The surfactant-treated animals showed significantly improved gas mixing efficiency in the lung with improved alveolar ventilation. Single exponential washout pattern dominated in both groups. Adequate functional residual capacity was established earlier after birth in the treated lambs than in the control animals. Lung mechanics in the treated group showed significant improvement in dynamic lung compliance. Surfactant treatment also improved gas exchange and reduced respirator pressure requirement. We speculate that the main functional effect of surfactant treatment in preterm lambs at risk to develop hyaline membrane disease is to maintain the patency of the peripheral airways in the lung, which improves diffusive gas mixing, alveolar ventilation, and gas exchange. The techniques used in this study should also be useful to evaluate lung function in preterm human infants after specific adaptation of the equipment size.
对有发生透明膜病风险的早产羔羊进行了羊肺表面活性物质预防性治疗的评估。八只机械通气的新生羔羊在分娩前接受了治疗，十只作为对照（胎龄129 - 131天）。使用气管内插管中的压力、流量和氮清除（100%吸氧期间的氮洗脱）测量来测试肺力学、功能残气量、肺泡通气、通气效率和通气分布。接受表面活性物质治疗的动物肺内气体混合效率显著提高，肺泡通气改善。两组均以单指数洗脱模式为主。治疗后的羔羊出生后比对照动物更早建立了足够的功能残气量。治疗组的肺力学显示动态肺顺应性有显著改善。表面活性物质治疗还改善了气体交换并降低了呼吸机压力需求。我们推测，表面活性物质治疗对有发生透明膜病风险的早产羔羊的主要功能作用是维持肺外周气道的通畅，这改善了扩散性气体混合、肺泡通气和气体交换。本研究中使用的技术经过设备尺寸的特定调整后，也应有助于评估早产人类婴儿的肺功能。
