Preload changes by positive pressure ventilation can be used for assessment of left ventricular systolic function

BACKGROUND: Assessment of preload independent left ventricular function with conductance volumetry is traditionally accomplished by inflating a balloon in the inferior caval vein. Our aim was to investigate if a similar change in preload could be achieved by positive pressure ventilation with large tidal volume. METHODS: Conductance volumetry generating left ventricular pressure-volume loops was used in seven pentobarbital-anesthetized pigs. Changes in preload recruitable stroke work were studied, comparing the effects of inferior vena cava occlusion (IVCO) or large tidal volume (LTV). Cardiodepression was induced by halothane anesthesia and halothane + phenylephrine, and stimulation by epinephrine infusion. RESULTS: Although the decreasis in left ventricular end diastolic volume was slightly less with LTV (16.5 +/- 1.7 ml, mean +/- SEM) than with IVCO (22.4 +/- 1.7 ml) (P < 0.0001) the PRSW-slopes showed a high degree of correlation (r=0.80, P < 0.0001). Although peak tracheal pressures increased significantly to 27.8 +/- 0.9 mmHg during LTV, esophageal pressures (used as an indicator of pericardial pressure) were unchanged. CONCLUSIONS: Positive pressure ventilation with LTV is similar to IVCO in creating transient changes in preload, necessary for assessment of left ventricular systolic function. This observation was valid also during drug-induced cardiac depression and stimulation. The preload recruitable stroke work used for this validation was shown to be a reliable and stable method.     

“气至病所”对相关皮瓣浸泡液内5-羟色胺、肾上腺素、去甲肾上腺素含量的影响

为研究“气至病所”的外周神经体液机制 ,本课题借用福尔马林试验 ,在大鼠一侧足底皮下注射 5%福尔马林 50 μL作为局部病灶 ,观察电针“阳陵泉”、“外丘”穴 (刺激参数为 1～ 3V ,4～1 6Hz,3 0min)对大鼠自发痛行为反应、相关皮瓣浸泡液内 5 羟色胺 ( 5 HT)、肾上腺素 (E)、去甲肾上腺素 (NE)含量的影响。结果表明 ,大鼠一侧足底注射福尔马林后 0～ 80min出现明显的自发痛行为反应 ,电针能显著减少大鼠福尔马林试验后的自发痛行为反应 ;大鼠一侧足底注射福尔马林后60min相关皮瓣浸泡液内 5 HT、NE、E含量显著增加 ,电针能拮抗大鼠福尔马林试验后相关皮瓣浸泡液内 5 HT、NE、E含量的上升。结果提示 ,循经电针可通过外周神经体液机制促使“气至病所” ,减少局部炎症介质的释放和交感传出导致的痛过敏反应     

氧气驱动雾化吸入肾上腺素在减轻新生儿机械通气拔管后喉水肿中的应用

目的观察氧气驱动吸入肾上腺素对减轻新生儿机械通气拔管后喉水肿的疗效。方法88例机械通气的新生儿随机分为两组,对照组43例,在拔管前1h静脉注射地塞米松0.5mg/kg,拔管后予以地塞米松2mg加生理盐水2ml,用6L/min氧气驱动雾化吸入,2h1次。治疗组45例,拔管后立即予以肾上腺素1mg加生理盐水2ml,用6L/min氧气驱动雾化吸入,2h1次,雾化4~5次后改用常规雾化吸入。两组均予以吸氧、吸痰、抗感染等处理。结果治疗组总有效率86.6%,明显优于对照组(总有效率67.4%)(P<0.05)。结论氧气驱动雾化吸入肾上腺素对减轻新生儿机械通气拔管后喉水肿效果明显,值得临床推广应用。     

Comparison of Epinephrine to Salbutamol in Acute Bronchiolitis

Objective

An appropriate treatment of acute viral bronchiolitis can reduce the symptoms, hospitalization duration and exorbitant costs which is imposed on the families and insurance organizations. This study was conducted to determine the efficacy of epinephrine in comparison with salbutamol in the treatment of the disease.

Methods

Forty infants aged one month to 2 years with acute bronchiolitis in Amin and Al-Zahra hospitals, during 2008, were enrolled in this study. The participants were randomized in two treatment groups to receive epinephrine 0.1 ml/kg or salbutamol 0.15 mg/kg. Three doses of each medication were prescribed at intervals of 20 minutes and continued every 10 minutes after the third dose. The patients in both groups were monitored and rated by RDAI, number of the hospitalized days in the hospital, level of oxygen saturation and vital signs.

Findings

Mean hospitalization duration was 3.3±1.1 and 3±0.9 in the patients receiving salbutamol and epinephrine, respectively (P=0.03). There was a significant difference in assessing RDAI index between the two groups (P=0.03). There were no differences in SPO2, PR, or RR variables in the studied intervals in both groups (P>0.05).

Conclusion

Regarding the effect of epinephrine on reduction of hospitalization duration and the RDAI index in patients with acute bronchiolitis, it seems that using epinephrine instead of salbutamol could be more effective in the management of the disease.     

肾上腺素对氯普鲁卡因硬膜外阻滞患者药效学和药代动力学的影响

目的观察1:20万肾上腺素对3％盐酸氯普鲁卡因硬膜外阻滞患者药效学和药代动力学的影响。方法择期行下腹部手术患者20例,ASAⅠ或Ⅱ级,随机分为2组(n=10):盐酸氯普鲁卡因组(C组)和盐酸氯普鲁卡因加肾上腺素组(CE组)。分别用3％氯普鲁卡因6 mg·kg-1(C组)和含 1:20万肾上腺素3％氯普鲁卡因6 mg·kg-1(CE组)硬膜外阻滞,记录局麻药的起效时间、运动阻滞起效时间和给药后20min时运动阻滞程度;分别在给药前及给药后3、6、9、11、13、15、17、20、30、45、60、 90min采取桡动脉血1．5ml,高效液相色谱法检测血浆氯普鲁卡因浓度,经计算机软件拟合血药浓度 -时间曲线,并计算各项药代动力学参数。结果两组局麻药的起效时间、运动阻滞起效时间和运动阻滞程度差异无统计学意义。C、CE组血药浓度峰值(Cmax)分别为0．49±0．47、(0．32±0．22)mg· L-1,达峰值时间(Tmax)分别为8±3、(9±4)min;血药浓度曲线下面积(AUC)分别为10±6、(7±4)μg· min·ml-1;清除速率常数(K)分别为0．32±0．21、(0．36±0．32)min-1;两组间Cmax、Tmax、AUC及K比较差异无统计学意义(P>0．05)。结论 1:20万肾上腺素对3％盐酸氯普鲁卡因硬膜外阻滞的药代动力学和药效学没有影响。     

右美托咪定对乳腺癌根治手术患者应激反应及细胞免疫的影响

目的：探讨右美托咪定对乳腺癌根治手术患者围手术期应激反应及术后细胞免疫的影响。方法选择2012年1月至2015年6月在我院择期全身麻醉下行乳腺癌根治术的患者108例,采用随机数字表法分为右美托咪定组（D 组）和对照组（C 组）,每组54例。D 组麻醉前15 min 内静脉滴注右美托咪定1．0μg／kg,麻醉诱导插管后,以0．5μg．kg －1．h －1维持至术毕。C 组给予等容量的生理盐水代替右美托咪定,其余麻醉同 D 组。分别测定麻醉前（T0）、术后4 h（T1）、术后1 d（T2）、术后3 d（T3）和术后7 d（T4）的血浆去甲肾上腺素（NE）、肾上腺素（E）、皮质醇（COR）、血清白细胞介素（IL）-6、T 淋巴细胞亚群（CD3＋、CD4＋、CD8＋、CD4＋／CD8＋）及 NK 细胞的水平。结果与 T0时比较,D 组各点血浆 NE、E、COR 及血清 IL-6水平差异无统计学意义（均 P ＞0．05）。C 组 T1～T3时血浆 NE、E,T2、T3时血浆COR,T2～T4时血清 IL-6水平均显著升高（均 P ＜0．05）。与 C 组比较,D 组 T1～T3时血浆 NE、E,T2和T3时血浆 COR,T2～T4时血清 IL-6水平均明显降低（均 P ＜0．05）。与 T0比较,T1～T3时两组 CD3＋及NK 细胞水平明显降低（均 P ＜0．05）。与 C 组比较,D 组 T1～T3时 CD3＋、NK 细胞明显升高,D 组 T2～T3时 CD4＋及 CD4＋／CD8＋明显升高（P ＜0．05）。结论全身麻醉期间持续静脉滴注右美托咪定可有效减轻乳腺癌根治术患者围手术期的应激反应,改善机体免疫状态。     

Lack of influence of glucagon on glucose homeostasis after prolonged exercise in rats

Summary The significance of glucagon for post-exercise glucose homeostasis has been studied in rats fasted overnight. Immediately after exhaustive swimming either rabbit-antiglucagon serum or normal rabbit serum was injected by cardiac puncture. Cardiac blood and samples of liver and muscle tissue were collected before exercise and repeatedly during a 120 min recovery period after exercise. During the post-exercise period plasma glucagon concentrations decreased but remained above pre-exercise values in rats treated with normal serum, while rats treated with antiglucagon serum had excess antibody in plasma throughout. Nevertheless, all other parameters measured showed similar changes in the two groups. Thus after exercise the grossly diminished hepatic glycogen concentrations remained constant, while the decreased blood glucose concentrations were partially restored. Simultaneously concentrations in blood and serum of the main gluconeogenic substrates, lactate, pyruvate, alanine and glycerol declined markedly. During the post-exercise period NEFA concentrations in serum and plasma insulin concentrations remained increased and decreased, respectively, while plasma catecholamines did not differ from basal values. Muscle glycogen concentrations decreased slightly. These findings suggest that in the recovery period after exhaustive exercise the increased glucagon concentrations in plasma do not influence gluconeogenesis.     

利多卡因混合不同剂量肾上腺素局部浸润麻醉对全麻下鼻内窥镜手术患者血液动力学的影响

目的 观察利多卡因混合不同剂量肾上腺素局部浸润麻醉对全麻下鼻内窥镜手术患者血液动力学的影响。方法 69例拟在全身麻醉下行鼻内窥镜手术的患者随机分为3组（n=23），采用含不同剂量肾上腺素的1％利多卡因进行鼻粘膜下多点浸润注射。Ⅰ组：含1：20万肾上腺素的1％利多卡因4ml（20μg）；11组：含1：10万肾上腺素的1％利多卡因4ml（40μg）；Ⅲ组：1％利多卡因4ml（不含肾上腺素）。采用阻抗心动图（ICG）测量并记录浸润麻醉开始前（基础值）、浸润麻醉开始后0．75、1．5、2．25、3、3．75、4．5、5．25、6min平均动脉压（MAP）、心率（HR）、心脏排血指数（CI）、外周血管阻力指数（SVRI）和加速度指数（ACI），同时评价术中出血状况。结果与基础值比较，Ⅰ组和Ⅱ组在浸润麻醉开始后1．5min时MAP下降，HR增快（P〈0．01）；从浸润麻醉开始后1．5minSVRI下降，CI、ACI上升，到浸润麻醉开始后6min时仍未恢复（P〈0．05或0．01）。与Ⅱ组比较，Ⅰ组在浸润麻醉开始后2．25、3、3．75minMAP下降，从2．25min起CI下降（P〈0．01或〈0．05）。与Ⅲ组比较，Ⅰ组、Ⅱ组出血较少（P〈0．01）；Ⅰ组和Ⅱ组之间差异无统计学意义。结论 全身麻醉下鼻内窥镜手术中局部浸润麻醉时，局麻药中肾上腺素的吸收会引起明显的血液动力学变化，推荐在鼻内窥镜手术中使用含有5μg/ml肾上腺素的利多卡因。     

肾上腺素在慢性阻塞性肺病伴急性左心衰竭病人的疗效分析

目的观察肾上腺素在慢性阻塞性肺病（COPD）加重期急性左心衰竭病人的治疗效果。方法将COPD加重期急性左心衰竭病人26例随机分为肾上腺素治疗组和西地兰治疗组，肾上腺素组12例，给予不少于1／3支（每支1mg）的肾上腺素肌注治疗（心音弱者1／3支，极弱1／2支，消失1支）；西地兰组14例，给予西地兰0．2mg＋5％葡萄糖10ml在5分钟内推入，以用药开始后15分钟为时间点监测心音强弱的改善程度，明显增强为显效，增强为有效，无变化为无效。结果肾上腺素组中显效10例，有效1例，无效1例；西地兰组中显效4例，有效6例，无效4例，两组急性左心衰治疗效果差异有显著性（P〈0．01）。结论肾上腺素可以用作COPD加重期伴急性左心衰竭病人的心衰改善药物。     

脊髓蛛网膜下腔内注射肾上腺素在横断脊髓大鼠中的中枢性升压效应

脊髓蛛网膜下腔内注射肾上腺素(1～4μg)引起横断脊髓的大鼠血压升高,并有量效关系,这一效应可被静脉注射神经节阻断药溴化六甲双铵(1mg)所消除。脊髓蛛网膜下腔内注射酚妥拉明(30μg)和哌唑嗪(15μg)预处理可对抗肾上腺素的作用;普萘洛尔(30μg)和育亨宾(15μg)则无效。结果提示,肾上腺素作用在脊髓内的肾上腺素能α_1受体上,具有中枢性升压作用。