肺泡表面活性物质对迷走神经性肺损伤肺功能和形态学的影响

The effect of pulmonary surfactant replacement on lung function in the acute lung injury induced by bilateral cervical vagotomy in guinea pigs

目的 观察气管内滴注肺泡表面活性物质 (pulmonarysurfactant,PS)对豚鼠迷走神经性肺损伤肺功能和形态学的影响。方法 2 4只豚鼠于颈部第 1气管软骨水平行双侧颈迷走神经切断术 ,吸纯氧PaO2 <2 0kPa时将动物分成 3组 :①表面活性物质治疗组 (PS组 )经气管内滴注内含 5mmol LCaCl2 的PS(5 0g L、10 0mg kg)混悬液 ;②生理盐水治疗组 (NS组 )经气管内滴注同体积生理盐水 (2ml kg) ;③机械通气治疗组 (MV组 )维持原通气状态 ,定压通气观察 2h。记录对血气分析、肺顺应性及组织形态学的影响。结果 PS组PaO2 、肺顺应性较NS组显著提高 (P <0 0 1) ,PaCO2 降低 (P <0 0 1) ;光、电镜结果提示PS组肺泡大部分复张 ,Ⅱ型细胞中板层体颗粒有部分释放。结论 外源性PS气管内滴注可提高迷走神经切断性肺损伤的肺顺应性 。

Objective To evaluate the effect of pulmonary surfactant(PS,50 g/L) 100 mg/kg instilled endotracheally on the lung function in acute lung injury induced by bilateral vagotomy. Methods In 24 adult guinea pigs bilateral cervical vagotomy at the level of the first tracheal ring was performed. When the PaO 2 was maintained at<20 kPa(F IO 2=1.0), the guinea pigs were randomly divided into 3 groups.In the surfactant group(group PS),100 mg/kg of the surfactant suspension(50 mg/ml) was instilled into the endotracheal tube. In the saline group(group NS),2.0 ml/kg of normal saline was instilled. In the control group(group MV),mechanized ventilation was kept on. Arterial blood gases,lung compliance,and morphology were studied during and after the experiment. Results A significant increase in PaO 2,lung compliance and decrease in PaCO 2 were noted after administration of surfactant.Histological examination of the PS treated lung showed alveolar expansion and partial release of lamellar bodies from typeⅡ epithelium cells. Conclusions Surfactant replacement can significantly improve lung compliance and gas exchange when lung injury is formed after bilateral vagotomy.