Department of Pediatrics, Université de Sherbrooke, Sherbrooke, Canada.
Crit Care Med. 2011 May;39(5):1097-103. doi: 10.1097/CCM.0b013e31820ead1a.
To test the hypothesis that total liquid ventilation enables a more effective and better tolerated lavage than a bronchoalveolar lavage performed with diluted surfactant in a newborn ovine model of severe acute meconium aspiration syndrome.
Prospective, randomized, interventional study.
Animal research laboratory at the Faculté de médecine et des sciences de la santé de l'université de Sherbrooke, Sherbrooke, Canada.
Twenty-three newborn lambs, <4 days, 2.5-4.0 kg in weight.
Animals were intubated, anesthetized, and paralyzed. Catheters were placed in the femoral artery and jugular vein. Severe meconium aspiration syndrome was obtained by instillation of a 25% dilution of human meconium in saline (1 mL/kg × 2). Lambs were then randomized in 12 total liquid ventilation-bronchoalveolar lavage (minute ventilation of 160 mL/kg/min with perfluorodecalin) vs. 11 bronchoalveolar lavage performed with diluted surfactant (conventional ventilation + 30 mL/kg in two aliquots bronchoalveolar lavage with 5 mg/mL BLES surfactant). Surviving lambs were ventilated for a total of 4 hrs and euthanized.
Arterial blood gases, systemic and pulmonary hemodynamic parameters using the thermodilution method, percentage of recovered meconium, and lung histologic scores. Total liquid ventilation bronchoalveolar lavage enabled a significantly higher PaO2 throughout the experiment. PaCO2, pH, and hemodynamic parameters were comparable for both groups except for an increase in mean pulmonary arterial pressure during total liquid ventilation. Total liquid ventilation bronchoalveolar lavage allowed for 43 ± 14% of the instilled meconium to be removed vs. 28 ± 10% for bronchoalveolar lavage performed with diluted surfactant (p = .022). Lung histologic analysis showed no difference between total scores.
Total liquid ventilation bronchoalveolar lavage is well tolerated and more effective in terms of meconium washout and gas exchange than bronchoalveolar lavage performed with diluted surfactant in this experimental model of severe meconium aspiration syndrome. These positive results open the way to further experiments in our ovine model, ultimately aiming at a clinical trial with total liquid ventilation bronchoalveolar lavage to treat severe meconium aspiration syndrome.
检验以下假说，即在严重急性胎粪吸入综合征新生羊模型中，与使用稀释表面活性剂进行的支气管肺泡灌洗相比，全液体通气可实现更有效的灌洗，且患者耐受性更好。
前瞻性、随机、干预性研究。
加拿大舍布鲁克大学医学与健康科学学院动物研究实验室。
23 只新生羔羊，<4 日龄，体重 2.5-4.0kg。
对动物进行插管、麻醉和麻痹。在股动脉和颈内静脉放置导管。通过向盐水中注入 25%稀释的人胎粪（1 mL/kg×2）获得严重胎粪吸入综合征。然后，将羔羊随机分为 12 例全液体通气-支气管肺泡灌洗（分钟通气量 160mL/kg/min，使用全氟癸烷）和 11 例用稀释表面活性剂进行的支气管肺泡灌洗（常规通气+30mL/kg，分两次用 5mg/mL BLES 表面活性剂进行支气管肺泡灌洗）。存活的羔羊总共通气 4 小时后安乐死。
使用热稀释法测量动脉血气、全身和肺血流动力学参数、回收胎粪的百分比和肺组织学评分。整个实验过程中，全液体通气-支气管肺泡灌洗可显著提高 PaO2。两组的 PaCO2、pH 和血流动力学参数相似，但全液体通气期间平均肺动脉压升高。全液体通气-支气管肺泡灌洗可清除 43±14%的注入胎粪，而用稀释表面活性剂进行的支气管肺泡灌洗可清除 28±10%（p=0.022）。肺组织学分析显示总评分无差异。
在严重胎粪吸入综合征实验模型中，与用稀释表面活性剂进行的支气管肺泡灌洗相比，全液体通气-支气管肺泡灌洗耐受良好，在胎粪冲洗和气体交换方面更有效。这些积极的结果为我们的绵羊模型进一步实验开辟了道路，最终旨在进行全液体通气-支气管肺泡灌洗治疗严重胎粪吸入综合征的临床试验。
