气管套囊对麻醉兔气管黏膜形态结构影响的研究

目的：探讨气管充气套囊对麻醉兔气管黏膜形态结构的影响。方法：家兔120只，按气囊压力不同随机分为A(30cmH2O维持1、2、4、5h)、B(20cmH2O维持1、2、4、5h)、C(20cmH2O维持2h气嶷放气10、20、30mm再充气2h)、D(对照组)4组，分别对气管黏膜作组织学和超微结构观察。结果：①气囊压力20cmH2O维持2h及气囊放气20min再充气2h光镜下黏膜结构未见异常，电镜显示纤毛细胞质及线粒体轻度肿胀；24h后光镜和电镜观察均未见异常；②气囊压力20cmH2O维持≥4h、30cmH2O≥2h气管黏膜充血、上皮细胞变性、坏死及脱落，拔管后24h黏膜表面有黏液及坏死物覆盖，病变程度随气囊压迫时间延长而加重。结论：①气囊压力以20cmH2O对气囊黏膜的损伤最轻；②气囊充气2h后放气≥20min再充气，可以减轻黏膜损伤。

Effect of inflated endotracheal tube on the tracheal mucosal morphology in anesthetized rabbits

Objective: To investigate the effects of inflating the cuff of endotracheal tube on tracheal mucosa in anesthetized rabbits.Methods:120 healthy adult rabbits were randomly divided into 4 groups according to the pressure of the cuff and time: A (30 cmH 2O for 1,2,4,5 h), B(20 cmH 2O for 1,2,4,5 h), C(2 h by 20 cmH 2O disinflat 10,20,30 min after reinflatly followed by 2 hours'reinflation) and D(control).Results: WT5BZ]Compared with the control group,abnormal structure of the epithelial lamina was not seen in the group with 2 hours endotracheal tube cuff inflated to 20 cmH 2O, 20 min disinflat and 2 hours reinflate, except slight mitochondrial swelling of ciliated epithelium cells. Over 4 hours of tube cuff inflation to 20 cmH 2O and 2 hours to 30 cmH 2O, histological and ultrastructural study showed the presence of congestion, epithelial degeneration, necrosis, exfoliation, acute inflammation, hemorrhage of mesenchyma of the mucosa of retropharynx and the upper part of trachea. The damages were more severe along with the time of tube cuff inflationConclusion:Damages of tracheal mucosa were minimal when the intracuff pressure was maintained for 2 hours by 20 cmH 2O, and the damages on the mucosa could be greatly decreased if the tube was disinflated for 20 min or more once two hours.