大鼠OSAHS模型的建立及其上气道流场特性的数值模拟分析

Modeling on rat model of OSAHS and its upper airflow characteristics simulation

目的研究大鼠上气道狭窄动物模型的构建方法及上气道狭窄后气流运动特性。方法将3月龄大鼠32只随机分为对照组和模型组,模型组每只大鼠在麻醉状态下给予0.1 mL透明质酸钠溶液软腭悬雍垂黏膜下注射处理。对照组和模型组在同等环境中饲养3月后,对两组动物分别进行CT扫描及呼吸检测。运用计算流体力学方法对比分析对照鼠和模型鼠上气道流场特性。结果 (1)模型组较对照组鼻咽部气道最小截面积明显减少,气道明显狭窄(P<0.05);(2)模型鼠呼吸急促、呼吸周期不稳定、咽腔呼吸波动较强;(3)在呼吸过程中,对照鼠鼻咽气道壁面最大剪应力分布较分散;而模型鼠鼻咽气道壁面最大剪应力分布较集中。结论软腭黏膜下注射透明质酸钠诱发了上气道狭窄,气道狭窄的动物模型与阻塞性睡眠呼吸暂停低通气综合征(OSAHS)病理学特征类似。上气道狭窄将导致呼吸困难,呼吸周期延长,且剪应力对咽部组织(特别是软腭及悬雍垂)的损伤作用更强,这加剧了咽部组织的力学重建。

Objective To study the modeling method of animal model on upper stenosis -airway of rats and its air flow characteristic. Methods Thirty-two 3-month old rats were randomly divided into two groups, the control group and the model group. For the model group, sodium hyaluronte of 0. l mL was injected into mucosa of the soft palate and uvula in each rat under the anesthetic state. After feeding under the same condition for 3 months, CT scans and respiratory experimental examinations were performed on the two groups, respectively. The com- putational fluid dynamic （CFD） method was then employed to simulate the airflow in upper airway. The flow char- acteristics were compared between the control rat and the model rat. Results （l） The minimum cross-sectional area of pharyngeal in the model group was reduced remarkably than that of the control group, showing that the airway of the model rats was significantly narrower than that of the control rats （ P 〈 0.05 ）. （2） The model rats became breathless, and their respiratory period became unsteady. The breath intensity of the model rat on the pharynx fluctuated more rapidly. （3） The maximum wall shear stress on the pharynx of the control rat was scattered at the respiratory phase while it was concentrated for the model rat. Cenclusieas The injection of sodium hyaluronte into mucosa of the soft palate and the uvula can induce the narrowness of the upper airway in the mod- el rat, which is similar to patients with obstructive sleep apnea-hypopnea syndrome （OSAHS） in pathology. The narrowness of the upper airway can cause dyspnea and extend respiratory period, The shear stress on the phar- ynx of the upper stenosis-airway induces stronger damage to the pharynx tissue, especially to the soft palate and uvula, which aggravates reconstruction of the pharynx tissue.