氩等离子凝固术和冷冻消融术对犬气管急性损伤的研究

Acute injury of the trachea by argon plasma coagulation and cryoablation in a canine model

目的 比较不同功率氩等离子凝固术（APC）及不同作用时间冷冻消融术对犬正常气管的急性损伤深度,以探讨不同处理方式的效果和安全性.方法 对8条杂种犬的气管行APC（功率分别为30和60W）和冷冻消融（时间分别为30和60s）处理,分为APC 30 W组、APC 60 W组、冷冻30 s组、冷冻60 s组及正常气管组,每组8例标本.48 h后行肉眼、组织病理和电镜观察,统计每种处理方式的损伤深度.结果 冷冻30 s组和冷冻60s组损伤深度均达气道软骨浅层,冷冻30 s组可见软骨细胞变性,冷冻60 s组软骨细胞变性增多,偶见软骨细胞坏死;APC 30 W组损伤深度达气道软骨浅层并可见部分软骨细胞坏死,APC 60 W组损伤深度达气道软骨深层及外膜层,可见多数软骨细胞坏死.前3组组织损伤深度8只动物均达到了软骨浅层,仅冷冻60 s组有2只达到了软骨深层;而APC 60 W组损伤深度8只动物均达到了软骨深层,与前3组处理方式比较差异有统计学意义（P＜0.05）.结论 常规参数的冷冻及APC消融对正常气管的损伤深度即可达软骨浅层,并导致软骨细胞变性,而APC 60 W组损伤深度可达气道软骨深层及外膜层,并造成软骨细胞坏死、气道壁不可逆的损伤.提示在气道腔内消融治疗中接近气管壁或消融管壁型病变时,应禁用APC消融治疗,而冷冻消融治疗最好控制在30 s以内.

Objective To observe the damage depth on normal canine trachea by using argon plasma coagulation （APC） at different power settings or cryoablation with different freezing duration,and to discuss the efficacy and safety of these different treatments.Methods APC （the power settings were 30 W and 60 W） and cryoablation （the freezing durations were 30 s and 60 s） were performed on the trachea of 8 dogs.The animals were killed 48 h after the treatment.The tracheal specimens were processed and divided into 5 groups：Cryoablation 30 s（Group A）,Cryoablation 60 s （Group B）,APC 30 W （Group C）,APC 60 W （Group D）and the control group.Gross observation,histopathological study and electron microscopic examination were performed.Results The tracheal injury in Group A and Group B reached the shallow part of airway cartilage layer,and 2 in Group B reached the deep part of airway cartilage layer.In Group A,cartilage cell degeneration could be seen,but in Group B,cartilage cell degeneration was worse and even necrosis was found.In Group C,the damage depth also reached the shallow part of the cartilage layer and necrosis of cartilage cells could be seen.In Group D,the damage depth reached the deep part of airway cartilage layer and even outer membrane of the trachea.More necrosis of cartilage cells was found.Conclusion When using cryoablation or APC with normal parameters,the injury in normal canine trachea could reach the shallow part of cartilage layer and cartilage cell degeneration could occur.When using APC 60 W,damage depth could reach the deep part of cartilage layer and even outer membrane of the trachea,leading to cartilage cell necrosis and even irreversible damage on airways.Therefore,it is highly recommended that,when managing lesions adjacent to or in the airway wall,APC ablation should be avoided and cryoablation time should be controlled within 30 s.