中文摘要：

目的改进实验大鼠经口气管插管定位技术,提高气管插管效率,减少并发症。方法采用临床套管针和静脉留置针组合,设计自制的气管插管定位防逆流装置。60只成年雄性SD大鼠随机分成A、B两组,A组40只,用于定位效果测试,B组20只用于防逆流测试。A组进一步分为A1组采用自行设计的定位装置,A2组采用雾气法,A3组采取棉纤维法进行定位判断。B组分为B1、B2两个亚组,均采取气泡逸出作为定位观察手段,不同的是B1使用圆台状防逆流装置,B2组不使用。采用透光法经口气管插管,观察并记录定位时间、呼气相定位效果、吸气相逆流水柱长度。A1组进一步行气管切开术在直视下明确定位状况。结果在呼气周期内,观察出泡口连续逸出3个以上的气泡,可以确定插管在位良好并通畅。定位时间：A1组需要（1.75±1.02）个呼吸周期,A2组需要（3.30±0.95）个呼吸周期,A3组需要（4.10±0.99）个呼吸周期。A2组与A3组两组间比较差异无显著性（P〉0.05）,A1组明确定位需要的时间明显少于A2、A3组,差异有显著性（P〈0.01）。B1组最长逆流水柱长度为（3.23±0.53）cm,B2组最长逆流水柱长度为（8.48±1.01）cm。结论自制实验大鼠经口气管插管的定位评估防逆流装置结构简单,使用方便,能有效提高气管插管的定位效率,有较好的实验应用价值。

英文摘要：

Objective To improve the orotracheal intubation verifying technique and reduce the complication of backflow in rat experiment. Methods A new position evaluation of anti-backflow device was designed and made of safety IV catheter and closed IV catheter system.60 adult male Sprague Dawley rats 216±20 g were randomly assigned to two groups：group A（n=40）for verifying placement,group B（n=20）for anti-backflow test.Group A was further divided into group A1 using self-designed positioning device,group A2 using aerosol,group A3 taking cotton fiber for positioning judgment.The group B was divided into two subgroups,B1 and B2,counting escaped bubbles as a means of positioning observation,the difference is that group B1 using frustum of a cone shape anti-backflow device,while the group B2 using common airway tube.Routine endotracheal intubation was performed to observe and record the time of positioning,the location of exhalation phase,and the length of inspiratory phase countercurrent water column.The group A1 further performed tracheotomy under direct vision clearly to confirm the anatomic positioning status.Results During the exhalation cycle,three or more bubbles were observed to escape continuously,indicating that the intubation tube was properly placed and open in the airway.Positioning time：It took 1.75±1.02 respiratory cycles in group A1,3.30±0.95respiratory cycles in group A2 and 4.10±0.99 respiratory cycles in group A3 to complete the assessment the positioning status.There was no statistically significant difference between groups A2 and A3（P〈0.05）.The time needed for group A1 was significantly shorter than that of groups A2 and A3（P〈0.01）.The longest countercurrent water column length in group B1 was 3.23±0.53 cm,and 8.48±1.01 cm in the group B2.ConclusionsThe new designed anti-backflow positioning evaluation device is a simple and convenient appliance to evaluate the location of orotracheal intubation in rat experiment.It can effectively improve the positioning efficiency and has pr