改良超滤对犬体外循环肺功能的影响

目的 通过观察改良超滤对犬体外循环肺功能的影响,探讨应用超滤对肺的保护作用.方法 选择18只健康成年犬随机分成对照组、CPB组和改良超滤组三组.三组动物均腹腔内注射戊巴比妥,麻醉生效后,仰卧位固定,气管插管,监测心电图、舌粘膜氧饱和度(SpO2)等,行右侧股动、静脉置管分别测平均动脉压(MAP)及中心静脉压(CVP).开胸时接麻醉工作站行机械通气,三组分别在开胸未行机械通气前、停机时、停机60 min采集动脉血行血气分析,计算犬RI和OI；取肺组织行HE染色观察病理学变化.结果 (1)肺组织病理学变化:对照组犬肺组织未见明显的病理变化,CPB后肺组织见大量的炎性细胞浸润,肺泡间隔增宽,甚至肺泡腔内有水肿波;改良超滤组肺组织改变明显轻于CPB组.(2)RI和OI的变化:开胸未行机械通气前三组犬RI和OI比较差异无统计学意义(P＞0.05).组内比较:A组各时间点RI、OI差异无统计学意义;B组、C组T2、T3时点的RI明显高于T1,而OI相反,差异有统计学意义(P＜0.05).组间比较:与对照组比较,CPB组、超滤组RI均增大、OI均减小；改良超滤组与CPB组比较在T3时点RI值减小、OI值增大,差异均有统计学意义(P＜0.05),T2时点差异无统计学意义.结论 体外循环中应用改良超滤可提高氧合指数,降低呼吸指数,减轻肺组织炎症反应,从而改善术后肺功能.

Effects of modified ultrafiltration on pulmonary tissue during cardiopulmonary bypass

Objective To search for the protect reaction of ultrafitration on pulmonary tissue through the observation of modified ultrafiltration on pulmonary tissue during cardio pulmonary bypass(CPB). Methods 18 adult hybrid healthy dogs were randomly divided into three groups(n=6) which were control group(group A),CPB group(group B) and modified ultra-filtration group(group C).All the dogs were anesthesitized with sodium pentobarbital.The trachea was inserted with a cuffed endotracheal tube.Detect ECG and Tongue mucosa oxygen saturation(SpO2).A femoral artery catheter was placed for mean arterial pressure(MAP) monitoring and blood sampling.A femoral vein catheter was placed for central venous pressure(CVP) monitoring and transfusion.Samples of arterial blood were repeatedly collected at the following time points: Before transfer(T1),end of CPB(T2),60min after the end of CPB(T3).Samples of lung tissue and 5ml of arterial blood were collected for detecting respiratory index and Oxygenation index.To check the pathological changes of lung tissue with HE stain. Results The pathological changes of lung tissue.There were no obvious pathological changes in control group of the dog lung tissue.After CPB the lung tissue infiltrated with massive inflammatory cell,alveolus capillary dilating and congesting,alveolar wall congesting obviously,alveolar septum widening,massive erythrocyte appearing in alveolar space and focal atelectasis.The changes of lung tissue in modified ultra-filtration group were statistically light than the group CPB.The changes of RI and OI,There were no statistics significant difference between RI and OI in all groups before transfer(T1)(P>0.05).There was no significant difference between RI and OI in A groups at different time points.(P>0.05).RI in group B and C at T2 and T3 were obviously higher than at T1,but OI was opposite.Comparing with A group,RI in group B and C were significantly higher,whereas OI were lower.RI was decreased in ultra-filtration group than the CPB at T3.OI was increased in ultra-filtration group compared with the CPB group at T3(P<0.05).There was no difference at T2. Conclusion Cardiopulmonary bypass can improve oxygenation index,reduce respiratory index,Reduce the lung tissue inflammation,so the postoperative lung function were improved.