Lam B C, Yeung C Y, Fu K H, Wong K Y, Chan F L, Tsoi N S
Department of Paediatrics, University of Hong Kong, Hong Kong, China.
Biol Neonate. 2000;78(2):129-38. doi: 10.1159/000014261.
We evaluated the effect of tracheobronchial lavage with diluted surfactant solution (bovine lipid extract surfactant, bLES) in a rabbit model of meconium aspiration. All animals were anaesthetized, tracheotomized and given 3-4 ml/kg of 25% slurry of human meconium into the endotracheal tube and mechanically ventilated for 1 h. The animals were then randomly assigned to surfactant lavage (n = 12) with 15 ml/kg of diluted surfactant at a concentration of 5.4 mg phospholipid/ml administered in aliquots of 2 ml; or simple endotracheal suction (control n = 12) when the oxygenation index (OI) was >/=15. Changes in the arterial blood gases and the histomorphological and radiological appearances of the lungs were recorded. The OI and arterial/alveolar oxygen tension (a/A PO2) of the surfactant lavage group improved significantly at 5 min post-treatment, and these improvements were observed throughout the ensuing 4 h of ventilation. There was significantly more solid content recovered by surfactant lavage compared with the control group (p = 0.0001). Radiologically, the post-treatment air space opacification scores of the lavage group were significantly lower compared with the control (p = 0.002). The post-treatment radiographs of the lavage-treated rabbits were rated by the radiologist, who was blinded to the treatment groups, as much improved in 5 and improved in 4, whereas the control rabbits were rated as much worse in 3 and worse in 4. Histological examination showed the lungs of the lavaged rabbits had significantly more normal airway (p < 0.0001), more fields showing completely normal airspace (p = 0.0001) and less fields showing severe overdistension with meconium (p = 0.0005). We concluded that lavage with diluted surfactant solution effectively washed out the meconium, improved gases exchanges, and improved the histological and radiological appearances in the rabbit model of MAS.
我们在胎粪吸入兔模型中评估了用稀释表面活性剂溶液（牛肺表面活性剂提取物，bLES）进行气管支气管灌洗的效果。所有动物均接受麻醉、气管切开，并经气管内导管给予3 - 4 ml/kg的25%人胎粪混悬液，然后进行机械通气1小时。然后，当氧合指数（OI）≥15时，将动物随机分为表面活性剂灌洗组（n = 12），给予15 ml/kg浓度为5.4 mg磷脂/ml的稀释表面活性剂，分2 ml等份给药；或单纯气管内吸引组（对照组n = 12）。记录动脉血气变化以及肺的组织形态学和放射学表现。表面活性剂灌洗组在治疗后5分钟时OI和动脉/肺泡氧分压（a/A PO2）显著改善，并且在随后的4小时通气过程中一直保持这些改善。与对照组相比，表面活性剂灌洗回收的固体成分明显更多（p = 0.0001）。放射学上，灌洗组治疗后的气腔模糊评分显著低于对照组（p = 0.002）。由对治疗组不知情的放射科医生对灌洗治疗兔的治疗后X光片进行评分，结果显示灌洗组5只改善明显，4只有所改善，而对照组3只情况恶化明显，4只情况恶化。组织学检查显示，灌洗兔的肺有明显更多的正常气道（p < 0.0001）、更多完全正常气腔的区域（p = 0.0001）以及更少显示有严重胎粪过度膨胀的区域（p = 0.0005）。我们得出结论，在胎粪吸入综合征兔模型中，用稀释表面活性剂溶液灌洗可有效清除胎粪，改善气体交换，并改善组织学和放射学表现。
