CPAP对OSAS小型猪上气道结构和功能的影响

The Effect of CPAP on the Structure and Function of Upper Airway of Mini Pig with OSAS

观察持续气道正压通气(Continuous positive airway pressure,CPAP)对阻塞性睡眠呼吸暂停综合征(OSAS)小型猪上气道结构和功能的影响。12只雄性成年小型猪随机分为A、B两组,给予连续22d、6h/d低压低氧处理。之后A组再给予30d、6h/d的CPAP治疗,B组饲养30d。低压低氧处理和CPAP治疗后,小型猪均行咽部CT扫描、口咽部呼吸压力检查,之后处死动物,取咽部组织行光镜检查。咽部CT扫描显示,A组CPAP治疗后舌骨前区,舌骨后区咽腔左右径显著增大(P<0.05),咽腔前后径无显著变化(P>0.05);舌骨前区后壁厚度较治疗前显著增加(P<0.05),侧壁厚度无显著差异(P>0.05);A组CPAP治疗后较B组咽腔前后径数值减小,左右径数值增大,但均无统计学意义(P>0.05)。A组CPAP治疗后软腭区、舌骨前区咽腔后壁显著较B组厚(P<0.05),侧壁厚度较B组无显著差异(P>0.05)。A组CPAP治疗后,咽部吸气负压较治疗前显著减小(P<0.05),亦低于B组(P<0.05)。光镜下,A组CPAP治疗后局部上皮组织增生,固有层炎症细胞浸润;咽肌横纹不清,局部肌纤维结构模糊,肌间隙有脂肪;B组病变程度较A组重。结果提示CPAP治疗使可OSAS小型猪上气道结构和功能趋于正常。

This study sought to assess the effect of CPAP on the structure and function of upper airway of mini pig with OSAS induced by altitude hypoxia. 12 adult male mini pigs were randomly assigned to 2 groups, named A and B. The mini pigs in group A were treated with altitude hypoxia 6 h per day for 22 days, and then with CPAP 6 h per day for 30 days. The mini pigs in group B were treated with altitude hypoxia only. Pharyngeal CT scanning and respiratory pressure testing were performed after the treatments . At last all mini pigs were sacrificed and their pharyngeal tissue was acquired for pathological examination. Result of pharyngeal CT scanning showed that, in group A , both of transverse diameters of pharyngeal cave in anterior and posterior areas of hyoid bone increased significantly after CPAP treatment（P〈0.05）,while the pharyngeal longitudinal diameters exhibited no significant change （P〉0.05）. The thickness of pharyngeal posterior wall of the anterior areas of hyoid bone increased significantly （P〈0.05） after CPAP, while the thickness of the lateral wall displayed no significant change. The pharyngeal longitudinal diameters of group A after CPAP were shorter than those of group B, and the transverse diameters were longer than those of group B, but these differences were not statistically significant （P〉0.05）. The pharyngeal posterior walls in soft palate area and anterior area of hyoid bone after CPAP were significantly thicker than those of group B（P〈0.05）, but there were no significant differences between the twogroups as far as lateral wall thickness was concerned （P〉0. 05）. After CPAP treatment ,the pharyngeal inspiration pressure in group A decreased significantly （P〈0. 05）, and the pressure was significantly lower than that of group B. Microscopic findings showed that the epithelium was proliferated partly after CPAP treatment. The muscle fibers of group A became fatter and were arranged disorderly with unclear transverse striation. The dropsied and congestive subcutaneous tissues were also infiltrated with inflammatory cells. These pathological changes were more obvious in group B. The results suggested that CPAP treatment could normalize the structure and function of pharyngeal tissue in OSAS mini pigs.