体外膜肺氧合在原发性及继发性肺动脉高压肺移植中的应用

目的 探讨体外膜肺氧合(ECMO)在肺移植围手术期应用的方法及疗效.方法 2005年11月至2009年7月,对30例原发性及终末期肺病伴继发性肺动脉高压的患者在肺移植术中应用了ECMO辅助,完成单肺移植18例,不横断胸骨序贯式双肺移植12例.2例患者在术前经股动静脉切开置ECMO管道,分别维持19 d和6 d,术中仍在ECMO支持下进行肺移植;其余患者在麻醉完成后置ECMO管道,开始肺移植术.移植完成后,受者在氧合和血流动力学平稳后撤除ECMO.结果 所有受者均顺利完成移植.27例受者于移植手术结束后顺利撤除ECMO;3例受者术后继续使用ECMO,直至血流动力学稳定,其中2例分别于术后36 h和7 d时顺利撤除,另1例术后用ECMO维持5 d后出现急性肾功能衰竭,术后2周时死于多器官功能衰竭.术后股动静脉切开处伤口感染2例,股动脉血栓形成(中度)1例,经治疗后均好转出院.结论 体外膜肺氧合可安全有效地应用于伴有原发性或继发性肺动脉高压患者的肺移植手术.术中应用ECMO能控制肺动脉高压,同时进行呼吸和循环支持,减少了肺移植手术的并发症.     

体外膜肺氧合在器官移植领域中的应用进展

体外膜肺氧合(ECMO)是一种能代替心肺功能、维持器官持续灌注的体外循环技术。近年来,因其出色的心肺支持功能,ECMO被越来越多地运用于器官移植领域,从器官捐献供者器官的保护,到器官移植受者移植前的安全过渡、移植中生命支持及移植后呼吸循环系统并发症的处理。ECMO在扩大供者来源、提高移植手术安全性和移植受者存活率方面发挥了重要作用。本文就ECMO在器官移植领域中的应用研究进展进行综述。     

肺移植患者应用体外膜肺氧合的护理

目的 探讨肺移植患者体外膜肺氧合(ECMO)应用过程中的观察内容及护理要点.方法 对6例肺移植应用ECMO患者采取开始转流后的常规护理,ECMO管路的管理,生命体征与实验室指标观察,营养支持等护理措施.结果 4例患者在肺移植术后即撤离ECMO;1例房间隔缺损伴Eisemenger患者由于术后血流动力学不稳定,连续使用ECMO 34 h后顺利撤离;1例双肺移植因术中出血多,血流动力学不稳定,术中紧急行ECMO支持,术后第7天顺利撤离.全组患者未发生ECMO相关并发症.术后4例患者顺利出院,出院后生活质量良好;1例由于术后出现MODS于术后第9天死亡,另1例再次移植患者处于术后恢复中.结论 ECMO应用过程选择合理的护理方案及手段,可及时发现应用过程中存在的问题,为医生及时、正确的处理提供依据.     

体外膜肺氧合在临床肺移植中的应用

目的 总结体外膜肺氧合(ECMO)技术在临床肺移植中应用的经验.方法 45例肺移植受者,年龄(50.5±8.6)岁(16～74)岁.原发病为肺纤维化合并肺动脉高压32例,慢性阻塞性肺病4例,矽肺2例,肺结核2例,弥漫性细支气管炎1例,支气管扩张2例,以及原发性肺动脉高压2例.其中3例受者在术前经股动、静脉切开置ECMO管道,分别维持13、19和6d后,在ECMO支持下接受了肺移植手术;40例受者在术中应用了ECMO辅助;2例未在体外循环下接受肺移植的受者,因原发性移植物功能丧失(PGD)于术后行ECMO辅助支持.结果 40例术中应用ECMO者,37例于术毕顺利撤除ECMO,术中辅助流量为(2.8±0.6)L/min,辅助持续时间为(7.7±0.9)h,存活31例;3例术后继续使用ECMO,直至血流动力学稳定,其中2例分别于术后36 h和7d时顺利撤除,另1例术后使用ECMO维持5d后出现急性肾功能衰竭,术后2周时死于多器官功能衰竭.2例术中无体外循环辅助受者和其余3例术中辅助受者因术后发生PGD或急性心力衰竭,而初次或再次使用ECMO,辅助流量分别为(2.5±0.3)L/min和(2.6±0.4)L/min,辅助持续时间分别为(53.5±21.9)h和(88.7±45.9)h,其中3例治愈出院,2例因多器官功能衰竭而死亡.所有受者均未发生明确与ECMO相关的并发症.结论 ECMO是肺移植围手术期支持的重要辅助工具,对于降低等待肺移植过程中的死亡率、稳定术中血流动力学、改善术后严重呼吸功能障碍以及原发性移植物功能不良,可以提供良好的辅助功能.     

肺移植患者应用体外膜肺氧合的护理

目的探讨肺移植患者体外膜肺氧合（ECMO）应用过程中的观察内容及护理要点。方法对6例肺移植应用EC—MO患者采取开始转流后的常规护理。ECMO管路的管理，生命体征与实验室指标观察，营养支持等护理措施。结果4例患者在肺移植术后即撤离ECMO；1例房间隔缺损伴Eisetnenger患者由于术后血流动力学不稳定，连续使用EC—MO34h后顺利撤离；1例双肺移植因术中出血多，血流动力学不稳定，术中紧急行ECMO支持,术后第7天顺利撤离。全组患者未发生ECMO相关并发症。术后4例患者顺利出院，出院后生活质量良好；1例由于术后出现MODS于术后第9天死亡，另1例再次移植患者处于术后恢复中。结论ECMO应用过程选择合理的护理方案及手段，可及时发现应用过程中存在的问题，为医生及时、正确的处理提供依据。     

体外膜肺氧合作为肺移植术前移植桥梁的研究进展

等待行肺移植手术治疗的终末期肺病患者,常可见病情急性加重而没有合适的供体可移植。这种情况下,体外膜肺氧合(ECMO)系统可作为移植桥梁,辅助患者等候到合适的供体,以行肺移植手术。本文旨在从置管策略、适应证及禁忌证、并发症、预后及其影响因素、伦理学争论等方面介绍ECMO作为肺移植术前移植桥梁的最新研究进展。     

体外膜肺氧合辅助下序贯式双肺移植的麻醉管理

目的 总结体外膜肺氧合(ECMO)辅助下序贯式双肺移植的麻醉处理及术中运用ECMO支持的经验.方法 8例终末期肺病患者术前进行了充分的调整和准备,手术均为双侧前胸切口序贯式双肺移植.麻醉诱导常规采用咪唑安定、芬太尼、依托咪酯及维库溴铵诱导,肌肉松弛后行气管内插管;术中麻醉维持以静脉持续泵注丙泊酚和维库溴铵,间断静注芬太尼.术中严密监测各项生命体征,根据血气指标及生命体征调节机械通气参数,必要时行手控通气.所有患者于麻醉诱导后进行股动、静脉穿刺置管,并给予ECMO辅助,转流期间维持激活凝血时间(ACT)160～200s,血流量1.8～2.5 L·m-2·min-1.结果 所有患者在麻醉诱导机械通气下生命体征平稳,手术过程顺利.结论 ECMO是双肺移植术中心肺辅助的有效手段,可提高肺移植手术的麻醉成功率.     

体外膜式氧合在肺移植中的应用六例分析

2002年9月至2006年9月我院共完成临床肺移植51例。其中6例患者应用体外膜式氧合（extracorpreal membrane oxygenation，ECMO）代替常规体外循环（cardiopulmonary bypass，CPB）进行了单、双肺移植手术，现报告如下。     

肺移植研究现状及移植期的规范化管理

肺移植是终末期肺疾病患者唯一的治疗手段,该领域也是目前国际范围内的研究热点。相关研究既促进了肺移植的进步与发展,也改善了移植后患者的生活质量。随着肺移植技术的发展,适应人群相关指南不断修订,供体肺来源也一直是所有移植中心亟待解决的问题。移植期的规范化管理涉及麻醉诱导、术中液体管理、气道管理、重要步骤的处理及术后疼痛管理等方面。体外生命支持(ECLS)包括体外循环(CPB)及体外膜肺氧合(ECMO)。随着ECLS技术的发展,ECMO作为肺移植桥梁在术中及术后循环支持中的优更加突出,帮助受体患者顺利度过肺移植窗口期。虽然肺移植在基础科学和临床研究方面都有许多进展,但要提高移植后的生存率,还须克服包括如何成功完成肺移植、扩大肺供体库、诱导耐受、预防移植后并发症、原发性移植物功能障碍(PGD)、细胞和抗体介导的排斥反应以及感染等在内的诸多问题。     

体外膜肺氧合在肺移植麻醉中的应用

目的 总结肺移植麻醉中体外膜肺氧合(extracorporeal memberane oxygenation,ECMO)辅助的适应证及术中运用ECMO支持的经验.方法 58例终末期肺病患者在麻醉诱导气管插管后,常规给予非术侧单肺通气30 min,监测肺动脉压(PAP)、氧分压(PaO2)、二氧化碳分压(PaCO2)、肺泡气·动脉氧分压差(PA-aO2)和呼吸力学等指标,根据监测指标调节机械通气参数,必要时行手控通气.17例患者分别因肺动脉高压、低氧血症和高碳酸血症而给予ECMO辅助,转流期间维持激活凝血时间(ACT)160秒～200秒,流量控制在1.8 L·m-2·min-1～2.5 L·m-2·min-1.结果 所有患者ECMO转流后PAP及PaCO:下降明显,氧合改善.麻醉伞程生命体征平稳.手术经过顺利.结论 ECMO是肺移植术中肺辅助的有效手段,可提高肺移植手术的麻醉成功率.原发性肺动脉高压、肺纤维化合并肺动脉高压、严重的低氧血症和高碳酸血症是肺移植术中ECMO转流的适应证.     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Immunomodulation in Transplantation with Photopheresis

Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.