摘要目的 评价七氟醚后处理对体外循环(CPB)下心脏瓣膜置换术患者心肌中性粒细胞浸润的影响.方法 择期行CPB下心脏瓣膜置换术的风湿性心脏病患者24例,年龄20 ～ 50岁,体重指数19 ～ 25 kg/m2,ASA分级和NYHA分级Ⅱ或Ⅲ级.采用随机数字表法,将患者随机分为2组(n=12):对照组(C组)和七氟醚后处理组(S组).静脉注射咪达唑仑、芬太尼、依托咪酯和罗库溴铵麻醉诱导,气管内插管后行机械通气.静脉输注芬太尼、咪达唑仑和维库溴铵维持麻醉.S组在主动脉及上腔静脉和下腔静脉开放时吸入5.0％七氟醚,当呼气末七氟醚浓度达1.7％时调整吸入浓度,维持该呼气末浓度5 min.分别于术前及主动脉开放后1、2、4h时采集桡动脉血样,测定血浆心肌肌钙蛋白T浓度.分别于打开心包时及主动脉开放后1h时取右心耳组织,测定髓过氧化酶表达水平,光镜下观察病理学结果.结果 与C组比较,S组主动脉开放后血浆心肌肌钙蛋白T浓度降低,心肌组织髓过氧化物酶表达下调(P＜0.05),主动脉开放后1h时心肌组织中性粒细胞浸润及心肌病理学损伤明显减轻.结论 七氟醚后处理可减轻CPB下心脏瓣膜置换术患者心肌损伤,其机制与抑制中性粒细胞浸润有关.

abstractsObjective To investigate the effects of sevoflurane postconditioning on myocardial neutrophil infiltration in patients undergoing cardiac valve replacement under cardiopulmonary bypass (CPB).Methods Twenty-four ASA Ⅱ or Ⅲ patients (NYHA Ⅱ or Ⅲ ) of both sexes aged 20-50 yr with BMI of 19-25 kg/m2 undergoing cardiac valve replacement under CPB were randomly divided into 2 groups ( n =12 each):group control (group C) and group sevoflurane postconditioning (group S).Anesthesia was induced with midazolam,fentanyl,etomidate and rocuronium and maintained with iv infusion of fentanyl,midazolam and vecuronium.The patients were intubated and mechanically ventilated (VT 8-10 ml/kg,RR 10-14 bpm,I∶E 1∶2,FiO2 100％ ).PETCO2 was maintained at 35-40 mm Hg.In group S sevoflurane was inhaled immediately after aorta and vena cava were unclamped.The end-tidal sevoflurane concentration was maintained at 1.7％ for 5 min.Arterial blood samples were collected before surgery and at 1,2 and 4 h after aortic unclamping for determination of plasma cardiac troponin T concentration.Myocardial specimens were obtained from right auricular appendage after opening of pericardium and at 1 h after aortic unclamping for microscopic examination and determination of myocardial myeloperoxidase expression.Results Sevoflurane postconditioning significantly decreased plasma cardiac troponin T concentration and myocardial myeloperoxidase expression and ameliorated histo-pathological damage in group S as compared with group C.Conclusion Myocardial neutrophil infiltration is involved in the protective effect of sevoflurane postconditioning against myocardial injury in patients undergoing cardiac valve replacement under CPB.