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31.
32.
Objective To observe the effects of dopamine in different doses on hemodynamics and cerebral oxygen metabolism in the early stage of post-resuscitation in rabbit with cardiac arrest. Methods Healthy adult rabbits were randomly(random number) divided into 4 groups according to the different doses of dopamine administration: control group (CG), low dose group (LG), medium dose group (MG), high dose group (HG), (n=15 in each group). Ventricular fibrillation (VF) was induced by electricity and cardiopulmonary resuscitation (CPR) was performed subsequently as the experiment designed. When 10 rabbits with restoration of spontaneous circulation (ROSC) were got each group, it was enough for experiment carried out. Cardiac output (CO), mean arterial pressure (MAP), heart rate (HR), systemic vascular resistance index (SVRI) and the cerebral local tissue blood oxygen saturation (TOI) were observed at 0 min, 15 min, 30 min, 60 min, 120 min after ROSC. The animals were sacrificed at 120 min after ROSC, brain tissues were harvested for study by using HE staining. Repeated measure analysis of variance was used to determine the statistical significance among the four groups at different intervals. Multi-group quantitative data was analyzed by one way ANOVA and then further by LSD test for multiple comparisons. Chi-square test or Fisher's exact probabilities was applied for multi-group binomial classification variable. Log-rank test was used for comparisons of survival curves in four groups. A two-tailed value of P<0.05 was considered statistically significant. Results There were no differences in the rate of ROSC among groups. Compared with CG and LG, ROSC time was shorter in MG (27715 vs. 19012, PO.01 ; 25216 vs. 19012, P=0.016 ) with higher 120 min survival rate ( 20% vs. 90%,∗2=9.899, P=0.005; 30% vj. 90%,∗2=7.5, P=0.02) . CO was higher in MG than that in other groups at all given intervals in the early stage of post-resuscitation(P<0.05). MAP levels were significantly higher in MG and HG compared with CG and LG at given intervals 15 min after ROSC (P相似文献
33.
右室流入道间隔部起搏对心脏血流动力学和心室激动顺序的影响 总被引:2,自引:0,他引:2
目的通过与右室心尖部(RVA)和右室流出道(RVOT)起搏比较,探讨右室流入道间隔部(RVIS)起搏对血流动力学和心室激动顺序的影响。方法选择24例阵发性室上性心动过速需行射频导管消融术(RFCA)且心功能正常和无室内传导阻滞的患者。在RFCA成功后,置入漂浮导管行血流动力学监测,用心室起搏电极以同一频率随机顺序起搏RVIS、RVOT和RVA,分别测定和比较各部位起搏时的心输出量(CO)、心脏指数(CI)、平均肺动脉压(mPAP)、肺毛细血管楔嵌压(PCWP)以及体表心电图上QRS波时限、JTc间期(经心率校正后的JT间期)和额面平均心电轴的变化。结果①RVIS、RVOT和RVA起搏时CO、CI、mPAP和PCWP等血流动力学指标均无差异(P>0.05)。②与正常窦性心律时QRS波时限比较,各部位起搏时QRS波时限均延长(P均<0.001),其中RVIS起搏时QRS波时限延长程度最小,RVA起搏时延长程度最大,各部位两两比较P均<0.05;JTc间期的变化有类似趋势,但各起搏部位之间比较无显著差异(P>0.05);与正常窦性心律时的额面平均心电轴比较,RVIS起搏时接近正常,RVOT起搏时电轴呈右偏趋势,RVA起搏时呈左偏趋势。结论①对心功能正常者RVIS起搏较RVOT和RVA起搏未表现出更佳的急性血流动力学效应。②RVIS起搏与RVOT和RVA起搏相比,能够保持相对正常的心室激动顺序。 相似文献
34.
Seyed Ahmad Samsamshariat Mehrnoosh Hashemzadeh Zahra Samsamshariat Mohammad-Reza Movahed 《Cardiovascular Revascularization Medicine》2005,6(2):70-72
BACKGROUND: Polyethylene Glycol (PEG) is a solvent and used in a wide range of biomedical applications. Many fatty-acid-based molecules cannot be administered without a solvent in vivo. PEG can be used to dissolve compounds to make them water soluble. However, the effect of PEG on the cardiovascular system has not been studied. In this study, we evaluated the effect of PEG on the cardiovascular system in rat models. METHODS: Twenty male Sprague-Dawley rats weighing 250-300 g were used in this study. The control group (10 rats) were injected intraperitoneally with 0.5 ml of 5% D/W in normal saline and the second group (10 rats) with PEG 400, 2 ml/kg ip, twice a day for 1 week. After 4 weeks, the rats underwent general anesthesia and a 1.4 French ultra miniature pressure volume catheter (Millar catheter) was placed in the left ventricle via the right carotid artery to measure comprehensive hemodynamic data. The data were analyzed with PVAN pressure-volume analysis software. RESULTS: All the systolic and diastolic parameters were similar in both groups except for the effective arterial elastance (Ea), which was decreased in the PEG group. There were no significant differences in maximum (dp/dt(max)) and minimum (dp/dt(min)) development of pressure stroke work, cardiac output, ejection fraction, end systolic volume (Ves), and end diastolic volume. CONCLUSIONS: We have demonstrated that PEG, as a solvent, decreases Ea in rats in comparison to a placebo. Therefore, PEG as a solvent should be used cautiously in the cardiovascular research. 相似文献
35.
观察右房左室起搏对充血性心力衰竭 (CHF)患者急性血流动力学的影响。 8例心功能II~IV级CHF患者 ,分别置入右房、右室和左室电极 (经冠状静脉窦 ) ,行不同部位组合起搏的急性血流动力学研究 ,其中 6例获得成功。使用Bitronic公司生产的双腔起搏分析仪 (ERA30 0 )分别行单纯右室心尖部 (RVA)、右房右室 (RA +RV)、右房左室 (RA +LV)、右房双室 (RA +BiV)起搏 ,同时用二维超声心动图测定上述四种起搏状况下的血流动力学参数 ,并进行比较。结果 :右房左室起搏和右房双室起搏血流动力学参数两者间无显著差异 ,但比单纯右室心尖部起搏和右房右室起搏有所改善。结论 :右房左室起搏似可使更多的CHF患者在得益于起搏治疗的同时明显降低医疗费用。 相似文献
36.
Dario Giugliano Federico Cacciapuoti Mario Verza Giuseppe Rosato Michele Varricchio 《Acta diabetologica》1979,16(4):331-337
Summary The aim of the present study was to evaluate possible hemodynamic effects of somatostatin in insulin-dependent diabetic subjects.
For this purpose, 7 insulin-requiring juvenile-onset diabetics were submitted to a short-term infusion of cyclic somatostatin
(250 μg/h, over 2 h) or saline in randomized order. Somatostatin infusion resulted in a progressive and significant decrease
in heart rate, stroke volume, cardiac index and velocity circumferential fiber; on the other hand, left ventricular ejection
time was augmented by somatostatin. None of these effects was seen in the saline control study. We conclude that somatostatin
exerts a negative inotropic effect in insulin-dependent diabetes. 相似文献
37.
Manfroi WC Caramori PR Zago AJ Melchior R Zen V Accordi M Gutierres D Noer C 《International journal of cardiology》2003,90(2-3):153-157
Background: Recently the new specific phosphodiesterase-5 inhibitor sildenafil was introduced into therapy for erectile dysfunction. The hemodynamic effects of sildenafil may be potentially hazardous for patients with cardiac disease. Sildenafil has been reported to augment the hypotensive effects of nitrates. There is sparse information regarding the systemic and pulmonary hemodynamic effects of a single oral dose of sildenafil in patients with stable angina. Methods: Male patients referred for coronary angiography with diagnosis of chronic stable angina were enrolled in this study to assess the acute hemodynamic effects of sildenafil. Patients receiving long-acting or sublingual nitrates for the last 6 h before the study were excluded. Hemodynamic measurement were taken during right and left heart catheterization in the basal state and 60 min after 50 mg of oral sildenafil. Results: Twelve patients (age 53±7 years) were studied. All had stable angina CCS class II or III. Four had previous myocardial infarction. By coronary angiography, seven patients had at least one coronary artery with >70% stenosis, four had at least one with 50–70% stenosis, and one had only intimal irregularities. There were no significant effects of sildenafil on systemic or pulmonary arterial pressure, left ventricle endiastolic pressure, cardiac output, and systemic or pulmonary vascular resistance (P>0.05 for all). No adverse events were observed. Conclusion: A single oral dose of sildenafil had no significant hemodynamic effect in supine patients with stable angina. Isolated administration of sildenafil does not appear to be associated to adverse cardiovascular effects. 相似文献
38.
目的探讨血红蛋白(Hb)对肝硬化大鼠血清一氧化氮(NO)含量及血流动力学的影响。方法应用57Co标记微球观察促红素长期治疗对肝硬化大鼠血流动力学参数的影响;应用荧光法测定大鼠血清NO含量。结果肝硬化大鼠全部出现高动力循环状态,且血清NO含量显著高于对照组、血Hb含量显著低于对照组;促红素治疗组,高动力循环状态明显改善,与未治疗组比较,Hb含量显著升高,血清NO含量显著降低。结论促红素致Hb增加,进而加速NO灭活对肝硬化高动力循环状态可能具有潜在治疗作用 相似文献
39.
颈内动脉中重度狭窄或闭塞患者同侧颈总动脉血流动力学的观察 总被引:1,自引:1,他引:1
目的观察颈内动脉(ICA)中、重度狭窄或闭塞患者同侧颈总动脉(CCA)血流动力学的改变,分析CCA血流动力学改变与ICA狭窄程度之间的关系。方法选择单侧ICA颅外段50%~99%狭窄或闭塞,且双侧CCA管径正常或狭窄率<50%的患者200例。按患侧ICA狭窄率将患者分为50%~69%狭窄组(50例)、70%~99%狭窄组(68例)及闭塞组(82例)。采用彩色多普勒超声测量双侧CCA的管径(ID)、收缩期峰值流速(PSV)、舒张末期流速(EDV)、平均流速(MV)及阻力指数(RI)。计算颈动脉血流量(BFV)、患侧的ICA与CCA峰值流速比值(PSVICA/PSVCCA)以及健侧与患侧CCA血流动力学各参数比值。结果①各组内患侧与健侧及各组间患侧CCA的ID比较,差异均无统计学意义。②与健侧比较,50%~69%组除患侧的PSVICA/PSVCCA增高外(1.90±0.36对0.88±0.23,P<0.001),其他参数差异均无统计学意义。③与同组健侧比较及与50%~69%组患侧比较,70%~99%组和闭塞组(闭塞组无PSVICA/PSVCCA)患侧的PSVICA/PSVCCA、RI增高(P<0.001);PSV... 相似文献
40.
经胸冠状动脉超声血流动力学参数评价冠状动脉狭窄程度 总被引:1,自引:1,他引:0
目的 探讨经胸冠状动脉超声(TTE)血流动力学参数评估冠状动脉狭窄程度的价值。方法 回顾性分析56例可疑冠心病患者的影像资料。测量冠状动脉正常组(无狭窄)、轻度狭窄组(狭窄率<50%)、中度狭窄组(狭窄率50%~69%)及重度狭窄组(狭窄率70%~99%)狭窄处TTE舒张期峰值流速(PDV),其远端最慢处流速(PDVDIS)及流速比值(PDV/PDVDIS)。并进行统计学分析。结果 TTE显示良好彩色血流的血管分支共113支;以CAG为金标准,其中冠状动脉正常组18支,轻度狭窄组19支,中度狭窄组30支,重度狭窄组46支。轻度狭窄组PDV、PDV/PDVDIS与冠状动脉正常组差异均无统计学意义(P均>0.05)。中度狭窄组PDV、PDV/PDVDIS高于冠状动脉正常组(t=5.13、7.11)和轻度狭窄组(t=4.45、6.59),重度狭窄组PDV、PDV/PDVDIS高于冠状动脉正常组(t=10.63、11.43)、轻度狭窄组(t=10.06、11.04)和中度狭窄组(t=7.07、5.17),差异均有统计学意义(P均<0.05)。PDV、PDV/PDVDIS与狭窄率呈正相关(r=0.82、0.87,P<0.01)。诊断冠状动脉中、重度狭窄时,PDV阈值分别为40.48、58.52 cm/s,敏感度分别为86.67%、86.96%,特异度分别为86.49%、92.54%;PDV/PDVDIS阈值分别为1.44、1.98,敏感度分别为90.00%、82.61%,特异度分别为97.30%、89.55%。结论 冠状动脉狭窄率与TTE血流动力学参数有关,PDV及PDV/PDVDIS可用以评价冠状动脉狭窄程度。 相似文献