大潮气量通气诱导幼猪呼吸机所致肺损伤并长期存活模型的建立

Establishing long-term surviving model of ventilator induced lung injury in piglets by large tidal volume ventilation

目的 建立幼猪呼吸机所致肺损伤模型并使其长期存活.方法 取健康幼猪21头,随机（随机数字法）分成预实验组（A组）9头、损伤组（B组）及对照组（C组）各6头.各组动物均予经口气管插管,颈内动脉及颈外静脉置管.预实验组予以60～80 mL/kg潮气量机械通气,损伤组子潮气量50 mL/kg,每小时行动脉血气分析,至动物死亡或血氧分压/吸人氧浓度（PaO2/FiO2）＜300mmHg（1 mmHg=0.133 kPa）停止通气,对照组自由呼吸.取不同时点（A,B组0 h-成模时;C组0～6 h）监测生命体征及各项呼吸力学、血气参数、血流动力学参数.实验数据行t检验或单因素ANOVA分析.实验结束后取左侧肺组织行病理检测.结果 大潮气量通气约6 h后,A,B组PaO2/FiO2值出现显著下降,与对照组相比较,差异具有统计学意义（P＜0.05）,肺形态学达急性肺损伤标准;给予50 mL/kg潮气量通气,动物可长期存活.结论 使用50 mL/kg大潮气量机械通气,成功建立幼猪呼吸机所致肺损伤模型,可长期存活.

Objective To establish a long-term surviving model of ventilator induced lung injury （ VILI） in piglets with large tidal volume ventilation. Methods A total of 21 piglets were randomly（ random number） divided into trial experiment group （group A,n =9）, injury group （ group B,n =6） and control group （ group C, n = 6）. Each piglet was intubated orotracheally and intravascular cannulae were inserted both into carotid artery and external jugular vein. The tidal volume in 60 - 80 ml/kg was given to rats of group A and 50 ml/kg to rats of group B, and free breath to rats of group C. Vital signs, pneumatic mechanics, blood-gas analysis and hemodynamics were monitored every hour （ group A and group B from just after the model established 0 h, group C from 0 ～6 h）. The t test or ANOVA test was used for statistical analysis. Left lung tissue was sent to biopsy after experiment. Results About 6 hours after mechanical ventilation with large tidal volume, PaO2/FiO2 lower significantly both in A and B group in comparison with control group （P 〈0.05 ） and histological changes hit the ALl criteria. Piglets ventilated with 50 ml/kg of tidal volume could survive for long-term. Conclusions The model of VILI in piglets made with 50 ml/kg of tidal volume ventilation was established successfully and survived for long-term.