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51.
目的探讨异氟醚预处理对心肌缺血-再灌注损伤的保护效应及机制。方法择期行心脏瓣膜置换术的风湿性心脏瓣膜病病人32例,随机分为异氟醚组和对照组,每组16例。异氟醚组以1.5%~2%异氟醚吸入复合芬太尼维持麻醉,心肺转流(CPB)开始前洗脱10min,CPB后以芬太尼维持麻醉;对照组以芬太尼维持麻醉。分别于麻醉前(T0)、CPB前(T1)、CPB30min(T2)、术后8h(T3)、24h(T4)抽取中心静脉血测定一氧化氮(NO)、NO合酶(NOS)与心肌肌钙蛋白I(cTnI)浓度。结果两组病人T0时NO、NOS与cTnI浓度差异无显著意义;异氟醚组T1、T2时NO、NOS浓度明显高于对照组(P<0·05),T3、T4时cTnI浓度明显低于对照组(P<0·05)。结论异氟醚具有心肌预适应作用,其机制可能与增加NO释放有关。  相似文献   
52.
不同脑保护方法中炎症反应对脑组织的影响   总被引:1,自引:1,他引:0  
目的 通过观察体外循环中采用不同脑保护方法时脑组织中各种炎性细胞因子的变化,探讨脑保护对炎症反应的影响。方法 将18只健康成年杂种犬随机均分为3组:常温体外循环组(normothermic cardiopulmonary bypass,NCPB组),深低温停循环组(deep hypothermic circulatory arrest,DHCA组),深低温停循环+间断选择性顺行性脑灌注组(intermittent selective antegrade cerebral perfusion,ISACP,DHCA+ISACP组)。术后检测犬脑组织的含水量,分离并取出海马,制备脑组织匀浆,采用放射免疫法测定白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF—α)的含量。在透射电子显微镜(TE)下检测海马脑组织的细胞形态学变化。结果 DHCA组的IL-1β和TNF—α含量明显高于NCPB组和DHCA+ISACP组(P〈0.01),但NCPB组与DHCA+ISACP组间比较差别无统计学意义(P〉0.05);TNF—α和IL-1β含量与脑水肿的程度呈正相关(r=0.987,0.942;P〈0.01)。TE检查显示DHCA组超微结构破坏较严重,而NCPB组和DHCA+ISACP组破坏较轻。结论 长时间DHCA会造成脑损伤,DHCA+ISACP有一定的脑保护作用,IL-1β和TNF—α在长时间DHCA中对脑损伤起一定的作用。  相似文献   
53.
目的 观察非体外循环冠状动脉搭桥手术的麻醉方法、术中病人血液动力学和氧代谢的变化以及术后病人的早期.非体外循环冠状动脉搭桥手术闰人20例,麻醉用咪唑安定0.1-0.2mg/kg、芬太尼15-30μg/kg及0.5%-2%的吸入麻醉药等,在切皮前、开心包后、心脏操作中、操作完成后10min及术毕观察血液动力学指标及脑氧饱和度,同时采集桡动脉和肺动脉血,测定血气及动脉血乳酸(ABL),计算氧供DO2)、氧耗(VO2)和氧摄取率(ERO2)。术后早期观察术后拔除气管插管、ICU停留及术后住院时间、并发症及死亡等情况。结果 心脏操作中MAP、SV、SI下降,HR、CVP升高,MAP下降以搭回旋支时最明显(P<0.01),HR升高以搭右冠时最明显(P<0.01);心脏操作中DO2降低(P<0.05),VO2无变化,ERO2升高(P<0.01);操作后DO2、ERO2恢复至操作前水平;操作后ABL升高(P<0.01)。结论 本组麻醉方法使病人完全度过非体外循环搭桥术,在心脏操作期易出现血压、每搏量、心指数下降,伴心率、静脉压升高,但时间短暂无严重后果,氧代谢紊乱及缺氧程度较轻。  相似文献   
54.
Objective To evaluate the effect of two kind oxygenators on polymorphonuclear neutrophil (PMN) apoptosis, and to give a method of inhibting the systemic inflammatory response syndrome(SIRS) to cardiopulmonary bypass(CPB). Methods Sixty VSD patients undergoing open heart surgery with CPB were randomly divided into two groups(n = 30): group B(bubble oxygenator), group M(membrane oxygenator). Blood samples were drawn from the central venous line before starting CPB, at the end of CPB, 4, 8 and 24 h after CPB. The PMN counts were performed by blood cell counter. PMN apoptosis and the expression of CD11b were evaluated by flow eytometry. The plasma concentration of elastase was determined by enzyme linked immunosorbent assays. Results The rates of PMN apoptosis were significantly reduced (P<0.05) and the PMN counts, the expression of CD11b and the plasma con-centration of elastase were remarkably increased after CPB(P<0.05), but at the end of CPB, 4 h and 8 h after CPB the rate of PMN apoptosis was higher in group M than that in group B. PMN counts, the expression of CDI lb and the plasma concentration of elastase were higher in group B than in group M (P<0.05). The PMN counts were higher in group B than in group M 24 h after CPB (P< 0.05). Conclusion XiJian-Ⅱ membrane oxygenator can increase PMN apoptosis and depress systemic inflammatory response better than XIJing-90 bubble oxygenator.  相似文献   
55.
56.
目的探讨乌司他丁(UST)对伴有肺动脉高压的患者实施心内直视手术时的肺保护作用。方法30例伴有肺动脉高压拟行心脏瓣膜置换术的患者随机均分为乌司他丁组(U组)和对照组(C组)。U组在劈胸骨和升主动脉开放前分别给予UST 0.6kIU/kg;C组在同时点给予等量生理盐水。手术开始前(T1)和升主动脉开放后30min(鱼精蛋白拮抗肝素后,T2)进行右肺中叶灌洗,酶联免疫吸附法测定肺灌洗液(BALF)中白细胞介素8(IL-8)浓度。采集桡动脉血行血气分析计算肺泡-动脉氧分压差(PA-aDO2)和呼吸指数(RI)。结果C组T2时BLAF中IL-8浓度、PA-aDO2、RI均较T1时明显升高(P<0.01);U组T2时各参数较T1时虽有升高,但明显低于C组(P<0.05)。结论乌司他丁可通过抑制肺内细胞因子释放减轻肺动脉高压患者行心肺转流心内直视手术后的肺损伤。  相似文献   
57.
Background: Inhaled administration of milrinone reduces pulmonary artery pressure. Pulmonary hypertension (PH) and right heart failure are associated with difficult separation from cardiopulmonary bypass (CPB). Therefore, inhaled milrinone could facilitate separation from CPB. Objective: To determine the impact and timing of administration of inhaled milrinone. Methods: A retrospective analysis of our experience on high-risk patients receiving inhaled milrinone was conducted to evaluate the postoperative course after administration of the drug. Results: Seventy-three patients received inhaled milrinone from June 2002 to February 2005. Mean age was 64 ± 13 years, with a mean preoperative Parsonnet score of 27 ± 14. Inhaled milrinone (5 mg) was administered before (n = 30) or after (n = 40) CPB, three patients had off-pump procedures and were excluded. CPB time was 145 ± 78 min with cross-clamping times of 91 ± 56 min without any significant difference between groups. Fifty-four patients (74%) had difficult separation from CPB, 14 patients (19%) required an intra-aortic balloon pump and 10 patients (14%) needed emergency reinitiation of CPB for hemodynamic instability. Ten patients died in the perioperative period (13.7%). Patients receiving inhaled milrinone prior to CPB initiation had a lowering pulmonary artery pressure after CPB (p < .01) and had less emergency reinitiation of CPB after weaning (3% vs 23%, p = .02) as compared to those with administration after CPB. No detectable side effects were directly linked to the administration of the drug. Conclusion: In this high-risk cohort, use of inhaled milrinone was well tolerated. Administration before initiation of CPB could help weaning from CPB.  相似文献   
58.
目的 应用大鼠脾损伤非控制性出血性休克模型探讨低压及低压扩容复苏治疗非控制性出血性休克的可行性。方法 雄性Wistar大鼠 5 0只 ,在大鼠脾损伤模型复制成功后随机等分为 5组 ,组 1 :假手术组 ;组 2 :休克未处理组 ;组 3:常压复苏组 (急救期控制MAP在 80mmHg以上 ) ;组 4 :低压复苏组 (急救期控制MAP在 6 0mmHg±5mmHg) ;组 5 :低压扩容复苏组 (急救期输入硝普钠 5 μg·kg- 1 ·min- 1 ,同时输液控制MAP在 6 0mmHg± 5mmHg)。结果  1~ 5组平均存活时间 (min)分别为 1 80、73.5 0± 8.0 4、1 1 4 .30± 31 .33、1 4 6 .70± 2 8.0 7和 1 71 .6 0± 1 5 .74 ,除组1、组 5外 (P =0 .0 6 71 ) ,其余各组间比较均有统计学意义 (P <0 .0 5 ) ;2~ 5组的急救期出血量 (ml·kg- 1 )分别为 :3.79± 1 .39、1 7.4 1± 8.88、8.6 7± 4 .5 9、1 0 .33± 4 .31 ,其中组 3出血量明显高于其他各组 (P <0 .0 1 ) ;组 4、组 5与组 2比较出血量明显增多 (P <0 .0 5 )。结论 在非控制性出血性休克治疗中 ,低压及低压复合适量硝普钠扩容复苏方法可改善组织代谢 ,提高生存时间 ,是更为理想的复苏方法  相似文献   
59.
Objective: Endothelial dysfunction represents a critical early component of organ injury following cardiopulmonary bypass. Recent studies demonstrate that the treatment with atorvastatin is associated with a significant improvement of endothelial function independently of its efficacy on cholesterol levels. Therefore, we investigated the effects of preoperative atorvastatin treatment on endothelium function after coronary surgery. Methods: Forty patients undergoing coronary surgery were randomized to treatment with atorvastatin (20 mg/die; N = 20) or placebo (N = 20) 3 weeks before surgery. Twenty normal patients served as control group. The flow-mediated dilations (FMD) of the brachial artery after both reactive hyperemia (endothelium dependent) and nitroglycerin administration (endothelium independent) were evaluated at baseline, at 48 h, and 5 days postoperatively. Results: At baseline, the endothelium-dependent FMD was significantly attenuated in coronary versus normal patients (normal 10.3 ± 1.8% vs coronary 4.1 ± 1.6%, p < 0.01). At 48 h postoperatively all patients exhibited a reduced FMD compared with baseline values: the endothelium-dependent dilatation showed a drop of 60.1 + 15% in the patients of the placebo group compared with 45.8 + 16.6% (p < 0.05) those in the atorvastatin group. At the univariate analysis, no significant correlation was found between serum levels of either total cholesterol or HDL cholesterol and FMD. The nitroglycerin-induced dilation was not significantly influenced by extracorporeal circulation as well as by atorvastatin treatment. Conclusions: The endothelial dysfunction following cardiopulmonary bypass is improved by the treatment with atorvastatin, by a mechanism unrelated to the drug efficacy of controlling serum cholesterol levels.  相似文献   
60.
OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.  相似文献   
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