肠道通透性测定及其临床意义

胃肠道是具有重要的免疫、内分泌和屏障功能的脏器。肠屏障的生物学研究已进行了近40年．随着研究的深入．人们对肠屏障衰竭的病理生理过程及其后果都有了较清楚的了解。肠屏障功能包括肠道黏膜的完整、正常肠道通透性、内脏血流、胃肠道激素的刺激、免疫功能、蠕动、黏液、泌酸及胃肠道正常菌群等．其中肠黏膜的完整性和通透性是最常用来代表肠屏障功能改变的两个因素。正常情况下，     

谷氨酰胺对胃癌术后化疗患者肠屏障功能的影响

目的观察谷氨酰胺对胃癌术后化疗患者肠屏障功能的影响。方法40例胃癌术后第4次化疗患者随机分为对照组和试验组,化疗方案为氟尿嘧啶(5-FU)、四氢叶酸(CF)加奥沙利铂(FOLFOX方案)。试验组化疗同时口服谷氨酰胺(30g/d),对照组化疗时未口服谷氨酰胺,检测两组患者化疗前后血浆谷氨酰胺浓度、二胺氧化酶(DAO)、D-乳酸水平及粪便中肠道菌群情况。结果化疗后对照组血浆谷氨酰胺浓度较化疗前明显降低(P0.05),试验组增加并明显高于对照组(P0.01);化疗后两组血浆DAO水平较化疗前均明显升高(P0.01),对照组较试验组升高更为明显(P0.05);对照组D-乳酸水平化疗后升高(P0.05),与试验组比较差异有统计学意义;试验组患者各肠道菌群总数化疗前后无明显变化,肠道菌群接近正常比例;对照组双歧杆菌、乳杆菌较化疗前明显下降(P0.01),大肠埃希菌、肠球菌明显升高(P0.01)。结论口服谷氨酰胺可提高胃癌术后化疗患者血浆谷氨酰胺浓度,有减轻损伤、调节肠道菌群微生态平衡、保护肠屏障功能的作用。     

重组人生长激素对肠道屏障功能的保护作用

目的探讨重组人生长激素对肠道屏障功能的保护作用及其机理。方法复习近年来国内、外相关文献并进行综述。结果重组人生长激素能使肠黏膜细胞和免疫细胞增殖、防止细胞凋亡,对抗NO、细胞因子及内毒素对屏障功能的损伤,增加肠道对谷氨酰胺的摄取和利用来维持肠黏膜的完整性和功能,以此维持肠道的屏障功能。结论重组人生长激素通过不同的途径保护肠道屏障功能。     

镇痛泵在妇产科病人术后的临床应用

目的：分析妇产科手术后白控硬膜外镇痛的效应。方法：采用布比卡因、芬太尼硬膜外连续阻滞麻醉，对219例妇产科术后患者镇痛作为观察组，未使用PCEA泵的同期妇产科术后病人为对照组，比较两组镇痛效果，生命体征功能恢复、排尿及副反应情况。结果：采用白控型镇痛泵病人，术后伤口疼痛时间及强度显著低于对照组（P〈0．01），两组副作用、肠功能恢复、排尿等，差异无显著性（P〉0．05）。结论：连续硬膜外阻滞麻醉后用自控镇痛泵于妇产科术后病人的镇痛，疼痛阻滞完善，方法简便，无明显不良影响。     

四君子汤加味对胃肠道手术后肠粘膜屏障功能的作用

目的:探讨中药四君子汤加味对胃肠道手术后病人肠粘膜屏障功能的保护作用及机理.方法:将40例胃肠道手术后病人随机分为对照组、肠内营养组和肠内营养加中药研究组.观察术前1 d、术后1 d和术后8 d的病人的营养指标(血清转铁蛋白、前白蛋白、视黄醇结合蛋白),免疫指标(IL-2、IL-6、sIL-2R),肠粘膜通透性指标(循环D-乳酸)的变化.结果:研究组病人术后8 d前白蛋白、视黄醇结合蛋白、IL-2等指标显著高于对照组和肠内营养组(P＜0.05),IL-6、sIL-2R、D-乳酸等指标显著低于对照组和肠内营养组(P＜0.05).结论:四君子汤加味可改善术后病人的营养状况,提高机体免疫机能,降低肠粘膜通透性,对肠粘膜屏障功能有明显的保护作用.     

超剂量氮芥体外循环区域灌注治疗下肢恶性肿瘤的麻醉体会

作者对20例下肢恶性肿瘤患者进行超剂量氮芥体外循环区域灌注治疗的麻醉进行了回顾性分析。认为麻醉方法以连续硬膜外阻滞较为理想,但应注意术中肝素化能使硬膜外腔出血或血肿形成的机会增多。麻醉操作应由技术熟练的麻醉医师进行,采用正中法穿刺,并选用较软的导管轻轻放入硬膜外腔,以尽量减少硬膜外腔血管的损伤,每次注药前,要测试感觉和运动功能的恢复情况,术后要及时随访病人,以便尽早发现有无     

肠黏膜生物屏障的研究现状和进展

肠黏膜屏障是指肠道能够防止肠内的有害物质如细菌和毒素穿过肠黏膜进入人体内其他组织、器官和血液循环的结构和功能的总和,包括机械屏障、生物屏障、免疫屏障和化学屏障。肠黏膜生物屏障是肠道黏膜屏障的重要组成部分,在保护人体肠道免于致病菌的侵袭、阻止肠道内细菌及内毒素移位中发挥着重要作用,肠道内益生菌与致病菌之间相互依赖相互制约,使肠道内微生态环境处于动态平衡,一旦平衡遭到破坏则出现肠黏膜生物屏障     

左旋布比卡因复合芬太尼术后硬膜外自控镇痛对细胞免疫功能的影响

左旋布比卡因是一种新型长效酰胺类局麻药。它是现今麻醉中常用药物布比卡因的左旋体。国外研究表明．左旋布比卡因中枢神经系统和心脏毒性明显低于布比卡因．且具有几乎与布比卡因相同的临床麻醉效能，现已广泛用于产科手术的麻醉、无痛分娩及术后镇痛。但左旋布比卡因复合芬太尼术后硬膜外自控镇痛对细胞免疫功能的作用尚未定论．本研究通过观察围术期病人细胞因子的变化．旨在探讨左旋布比卡因复合芬太尼术后连续硬膜外自控镇痛对机体细胞免疫功能的影响。     

肠内早期中药干预对肠粘膜屏障的保护作用

长期以来 ,人们对肠道的认识偏重于营养物质的消化、吸收功能。肠粘膜还具有屏障功能 ,这是肠道粘膜所具有的特定功能 ,能阻止肠道内细菌及其分解产物经肠壁逸至机体内。下面就肠粘膜的屏障功能及中药的作用做一综述1　肠粘膜屏障的组成及临床意义胃肠道不仅是一个传输、消化和吸收营养物质的消化器官 ,其粘膜还是一道分隔内外环境 ,保护机体免受细菌、毒素等有害物质侵袭的内在屏障。肠道具有近于网球场大小的人体最大的膜结构 ,凭这一层薄的柱状上皮将腔内存在的大量细菌及毒素和体内环境隔开。肠粘膜屏障是肠道防御机制最重要的环节 ,是…     

烧伤后细胞凋亡对肠黏膜屏障的影响

较大面积烧伤不仅引起皮肤或其深层组织的损伤，还会引起机体各个脏器和系统功能、代谢和形态学发生明显变化。其中严重烧伤后肠道病理变化的致病作用已得到广泛重视。过去人们认为严重创伤后肠道缺血、缺氧导致肠黏膜细胞坏死脱落，造成肠道内细菌和内毒素移位。近几年来，细胞凋亡的研究不断深入，创伤后缺血、缺氧条件下肠上皮细胞凋亡与肠黏膜屏障损伤的关系已引起了各国学者的关注，认为细胞凋亡在维持肠黏膜上皮细胞稳态中起重要作用。现将烧伤后细胞凋亡对肠黏膜屏障功能与结构的影响综述如下。     

Bacterial translocation secondary to small intestinal mucosal ischemia during cardiopulmonary bypass. Measurement by diamine oxidase and peptidoglycan.

OBJECTIVES: To demonstrate that small intestinal mucosal ischemia occurs during cardiopulmonary bypass by measuring serum diamine oxidase activity, an index of small intestinal mucosal ischemia, in perioerative patients undergoing cardiovascular surgery with and without cardiopulmonary bypass. METHODS: Twelve successive patients who underwent coronary artery bypass grafting with cardiopulmonary bypass (Group I) were compared to 10 patients who underwent off-pump coronary artery bypass grafting (Group II). Serum diamine oxidase activity, blood lactate concentration, and serum peptidoglycan concentration were measured perioperatively. RESULTS: Serum diamine oxidase activity rose after the start of cardiopulmonary bypass and continued to rise throughout cardiopulmonary bypass in Group I, while activity was unchanged in Group II. The serum lactate concentration mirrored the change in the diamine oxidase activity in both groups. The peptidoglycan concentration in Group I rose after the start of cardiopulmonary bypass and returned to near normal concentrations after surgery. CONCLUSIONS: The parallel rise in diamine oxidase activity and the serum lactate concentration in Group I implies that ischemic injury to the mucosa of the small intestine occurs during cardiopulmonary bypass, and the rise in the serum peptidoglycan concentration indicates that bacteremia did occur. Thus, cardiopulmonary bypass causes hypoperfusion of small intestinal mucosa and consequently bacterial translocation.     

Localization and changes of diamine oxidase during cardiopulmonary bypass in rabbits

BACKGROUND: We previously observed increased serum diamine oxidase activity during clinical cardiopulmonary bypass, indicating small intestinal mucosal ischemia followed by bacterial translocation. MATERIALS AND METHODS: In seven female rabbits undergoing cardiopulmonary bypass for 1 h, we analyzed the localization of diamine oxidase immunohistochemically, and measured its activity in serum and abdominal organs before and after cardiopulmonary bypass (CPB). RESULTS: Preoperatively, diamine oxidase activity and immunoreactivity were high in the small intestine, localized to villus tips. Serum activity increased significantly after CPB, whereas small intestinal diamine oxidase decreased with mucosal injury. CONCLUSIONS: In this model serum diamine oxidase activity appeared to reflect CPB induced intestinal mucosal injury.     

Cardiopulmonary bypass in humans--jejunal mucosal perfusion increases in parallel with well-maintained microvascular hematocrit

BACKGROUND: An imbalance between splanchnic oxygen supply and demand occurs during cardiopulmonary bypass (CPB) in man, which might disrupt the intestinal mucosal barrier function. The aim of the present study was to evaluate the effects of mild hypothermic CPB on intestinal mucosal perfusion in man undergoing cardiac surgery. Additionally we aimed to identify variables, which independently could predict changes of intestinal mucosal microcirculatory variables during CPB. METHODS: Jejunal mucosal perfusion (JMP), jejunal mucosal hematocrit (JMHt), red blood cell (RBC) velocity and arteriolar vasomotion using endoluminal jejunal laser Doppler flow metry were studied in eight cardiac surgical patients before and during CPB at a temperature of 34 degrees C. RESULTS: Cardiopulmonary bypass and the accompanied hemodilution (25-30%) induced a 44% increase in JMP (P < 0.05) and a 42% increase in RBC velocity (P < 0.01), with no change in JMHt. The oscillation amplitude of JMP, at a fundamental frequency of 2.8 cycles min(-1), increased with 175% (P < 0.05) during CPB. Splanchnic oxygen extraction increased by 64% during CPB (P < 0.05). Stepwise multiple regression analysis identified systemic hematocrit, arterial O2 and CO2 tension and splanchnic oxygen extraction as independent predictors of RBC velocity during CPB (R2=0.63, P < 0.001). The oscillation amplitude of JMP was predicted by RBC velocity and splanchnic oxygen extraction (R2= 0.68, P <0.0001). CONCLUSIONS: The increase in RBC velocity and enhanced arteriolar vasomotion, as well as maintained jejunal mucosal hematocrit, are microcirculatory, compensatory mechanisms for the splanchic oxygen supply/demand mismatch seen during cardiopulmonary bypass in humans.     

Anesthetic management of concomitant coronary artery bypass grafting without cardiopulmonary bypass and left lower lobectomy

This case report describes an anesthetic management of a patient who received successful concomitant coronary artery bypass grafting without cardiopulmonary bypass and left lower lobectomy. A 66-year-old man presented for left lower lobectomy. His medical history included angina pectoris under control with isosorbide and nifedipine. Preoperative coronary angiography revealed multiple stenosis [100% at right coronary artery (# 2), 99% at left anterodescending artery (# 7) and 90% at left circumflex artery (# 11)]. Concomitant coronary artery bypass grafting without cardiopulmonary bypass and left lower lobectomy were scheduled. Anesthesia was maintained with combined total intravenous anesthesia (propofol and fentanyl) and continuous thoracic epidural anesthesia. Postoperative pain was well controlled with continuous epidural analgesia (TEA) and patient control analgesia (PCA). There were no signs of postoperative respiratory complications and myocardial ischemia. Combined total intravenous and continuous thoracic epidural anesthesia has multiple benefits for concomitant coronary artery bypass grafting without cardiopulmonary bypass and left lower lobectomy.     

Monitoring oxygenator expiratory isoflurane concentrations and the bispectral index to guide isoflurane requirements during cardiopulmonary bypass

OBJECTIVE: The purpose of this study was to measure the changes in isoflurane requirements during the rewarming phase of cardiopulmonary bypass with moderate hypothermia. DESIGN: An observational study. SETTING: University hospital, single center. PARTICIPANTS: Forty patients undergoing elective coronary artery bypass surgery with cardiopulmonary bypass. INTERVENTIONS: Isoflurane requirements were quantified by measuring the concentrations in the oxygenator expiratory gas. Anesthesia was guided by bispectral index monitoring. MEASUREMENTS AND MAIN RESULTS: Isoflurane concentrations required to maintain the bispectral index between 40 and 50 during the rewarming phase of cardiopulmonary bypass were measured. There was a progressive increase in expiratory isoflurane requirements during rewarming from 30 degrees C to 37 degrees C, with a Pearson correlation coefficient of 0.78. There was a significant difference in the concentration required at 30 degrees C (0.41% +/- 0.14%) compared with 37 degrees C (1.00% +/- 0.12%). CONCLUSION: Isoflurane requirements are reduced during hypothermic cardiopulmonary bypass. Monitoring anesthetic concentrations in the oxygenator expiratory gas may be a useful adjunct to monitoring the depth of anesthesia.     

Conscious off pump coronary artery bypass surgery--an audit of our first 151 cases.

PURPOSE: An audit of our first 151 cases of conscious off pump coronary artery bypass (COPCAB) surgery with epidural anesthesia as sole anesthetic. METHODS: Patients underwent conscious off pump coronary artery bypass (OPCAB) surgery using high thoracic epidural anesthesia. The epidural catheter was inserted on the day before the surgery. RESULTS: There were 118 male and 33 female patients. The incision was via midsternotomy except in 3 patients. Single graft was performed in 25 patients, double in 61, triple in 46, quadruple in 19. Twenty-nine patients developed pneumothorax. Three patients required conversion to general anesthesia. In one patient cardiopulmonary bypass (CPB) was instituted. There was no mortality in the group. CONCLUSION: Our experience shows that conscious OPCAB surgery can be performed safely in selected patients.     

双歧三联活菌预处理对体外循环后大鼠肠黏膜屏障功能的影响

目的 探讨双歧三联活菌预处理对体外循环(CPB)后大鼠小肠黏膜屏障功能的影响.方法 成年雄性SD大鼠24只,体重350～450 g,随机分为3组(n=8):假手术组(S组)、CPB组和双歧三联活菌预处理组(P组).CPB开始前7 d,P组每天用双歧三联活菌2 ml(含活菌数1×10~7 CFO)灌胃,S组和CPB组用生理盐水2 ml灌胃.第8天进行CPB 60 min.CPB结束后2 h时处死大鼠,抽取门静脉血,采用分光光度法测定血浆二胺氧化酶活性和D-乳酸浓度,鲎试验偶氮显色法测定内毒素浓度,放免法测定血浆TNF-α和IL-6的浓度.取腔静脉血,肝、肺、肾组织及肠系膜淋巴结,分别接种于血平皿上培养,24 h后鉴定细菌生长情况及细菌种类,光镜下观察小肠上皮组织病理学.结果 与S组相比,CPB组和P组血浆D-乳酸、内毒素、TNF-α和IL-6的浓度、二胺氧化酶活性及细菌易位率升高(P<0.05);与CPB组相比,P组上述各指标降低(P<0.05).病理结果显示P组小肠上皮组织损伤程度较CPB组明显减轻.结论 双歧三联活菌预处理可在一定程度上抑制炎性反应,保护CPB后大鼠小肠黏膜屏障功能.     

Molecular mechanisms transducing the anesthetic, analgesic, and organ-protective actions of xenon

The anesthetic properties of xenon have been known for more than 50 yr, and the safety and efficacy of xenon inhalational anesthesia has been demonstrated in several recent clinical studies. In addition, xenon demonstrates many favorable pharmacodynamic and pharmacokinetic properties, which could be used in certain niche clinical settings such as cardiopulmonary bypass. This inert gas is capable of interacting with a variety of molecular targets, and some of them are also modulated in anesthesia-relevant brain regions. Besides these anesthetic and analgesic effects, xenon has been shown to exert substantial organoprotective properties, especially in the brain and the heart. Several experimental studies have demonstrated a reduction in cerebral and myocardial infarction after xenon application. Whether this translates to a clinical benefit must be determined because preservation of myocardial and cerebral function may outweigh the significant cost of xenon administration. Clinical trials to assess the impact of xenon in settings with a high probability of injury such as cardiopulmonary bypass and neonatal asphyxia should be designed and underpinned with investigation of the molecular targets that transduce these effects.     

Resection of tracheal carcinoma using partial cardiopulmonary bypass--report of a case]

A 43-year-old male was admitted to our hospital with chief complaints of stridor and dyspnea. Bronchoscopy revealed a tumor obstructing almost the whole lumen of the trachea. As it was impossible to insert an endotracheal tube into the distal site of the stenosis in the mediastinum, we used partial cardiopulmonary bypass to maintain gas exchange. The axillary artery and the femoral artery and vein were cannulated for the bypass using local anesthesia. During 105 minutes of bypass, the PaO2 value was good but the PaCO2 value increased up to 70 mmHg. After the trachea was opened, the anesthetic gas was administered across the operative field through the endotracheal tube and the cardiopulmonary bypass was discontinued. Tracheolaryngectomy and permanent tracheostomy with relocation to the right and caudal side of the brachiocephalic artery was performed successfully. The post operative course was very smooth. The patient has been well for 6 months since the surgery. Partial cardiopulmonary bypass proved to be useful for maintaining gas exchange during reconstructive surgery of the trachea. We treated a case of tracheal carcinoma by resection while using partial cardiopulmonary bypass. We believe this is the ninth such case reported Japanese literature.