大鼠同种异体肢体移植急性排斥反应动物模型的制作

目的　建立同种异体肢体移植的动物模式。　方法　Wistar大鼠的肢体移植给SD大鼠 ,术后抗炎 ,显微外科常规护理 ,观察移植后宿主及移植物的变化。　结果　大鼠的异体肢体移植 8例 ,成功 6例 ;移植物的排斥反应再现稳定 ,生存时间为 (14± 2 )d。　结论　Wistar→SD大鼠的同种异体肢体移植模型的建立 ,为基础研究提供了动物模型     

大鼠原位异体睾丸移植模型的建立

目的 应用显微外科技术建立大鼠原位异体睾丸移植模型。方法 带供睾动脉的腹主动脉与受体腹主动脉端侧吻合，供睾静脉应用Cuff管技术与受体左髂总静脉端端吻合，供、受体输精管作端端吻合。结果 在施行的20例手术中，19例移植成功。结论 此种模型建立原位异体睾丸移植横至的方法是可行的。     

大鼠胰十二指肠肾脏联合移植模型的实验研究

目的：为了进行胰肾联合移植基础研究，建立一种简易可靠的大鼠胰十二指肠肾脏联合移植（SPKT）模型，方法：雄性SD大鼠作同品系异体移植的供受体，受体尾静脉注射链脲霉素（STZ）50mg/kg，建立大鼠糖尿病模型，在保存液中，移植物门静脉与肾下下腔静脉作袖套式吻合；移植物肾上腹主动脉，肾上下腔静脉分别与受体肾下腹主动脉，肾下下腔静脉显微缝合吻合，移植物十二指肠与受体十二指肠端侧吻合，移植物带输尿管的膀胱片与受体膀胱吻合。结果：血管吻合时间及受体手术时间短，手术成功率为88％，移植胰腺及肾脏功能良好。结论：此模型是一种简易可靠的大鼠胰十二指肠肾脏联合移植模型。     

大鼠肢体移植急性排斥反应动物模型的比较研究

目的 探讨建立更简便有效的大鼠肢体移植急性排斥反应动物模型.方法 以Wistar大鼠为供体,SD大鼠为受体,将Wistar大鼠的后侧(左侧或右侧)肢体移植给SD大鼠.实验分成两组,传统术式组:离断SD大鼠原有后侧肢体,将Wistar大鼠同侧肢体通过固定骨骼、吻合血管神经、缝合肌肉皮肤的方法移植给SD大鼠;改进术式组:保留SD大鼠原有后侧肢体,将供体Wistar大鼠的后侧肢体按照左肢配右肢或右肢配左肢的原则,通过缝合皮肤和肌肉的方法固定于SD大鼠后侧肢体的内侧,只吻合股动、静脉,不吻合神经、血管,不固定骨骼.记录两种模型的手术时间、手术前后的体重改变,术后显微外科常规护理,记录移植后宿主饮食量、体重变化、观察移植物变化、手术成功率.结果 两种肢体移植模型各50例,74例成活,移植物排斥反应再现稳定,生存时间均为(14±2)d.传统组和改进组的手术时间分别为(125±40)min、(70±21)min,手术前后平均体重减少量分别为(3.78±1.09)g、(2.05±0.90)g.术后3 d左右,改进组大鼠体重开始增加,传统组1周内体重均持续减少.手术成功率传统组为38%,改进组为90%.在以上4个方面,改进组明显优于传统组(P<0.05).结论 改良术式具有操作简单,成功率高,手术时间短,对大鼠创伤小,大鼠恢复快,值得借鉴和推广.     

大鼠原位肾脏移植模型的显微外科技巧

目的 探讨建立稳定、可靠的大鼠原位肾脏移植模型的显微外科手术技巧。方法供体手术经腹主动脉以4℃乳酸钠林格注射液对供肾进行原位灌洗。受体手术采用将供肾的血管与受体的同名的血管作端端吻合的大鼠原位左肾移植。结果 共施行大鼠原位肾脏移植手术120例，手术成功率为91．5％；非干预组中，同系移植大鼠1个月存活率为82．9％。结论 肾动、静脉和输尿管的重建均采用端端吻合法而无须阻断腹主动脉和下腔静脉，大大减少了对受体循环系统的影响。该模型稳定性强、重复性好，适合于移植免疫的基础研究。     

20%小体积的大鼠肝脏移植模型

目的 应用显微外科技术建立20%小体积移植物的大鼠原位肝脏移植模型.方法 原位移植建立20%小体积大鼠肝脏移植模型.雄性Lewis大鼠40只,供体20只,受体20只.供肝经门静脉用4℃ UW液灌注.肝上下腔静脉用端端吻合连续缝合的方法.肝下下腔静脉和门静脉分别用套管方法固定.套叠缝合法重建肝动脉.胆管重建采用内支架管端端连接的方法.观察移植物的存活率.免疫组化检测肝细胞摄取溴脱氧尿核苷的情况.结果 共施行肝脏移植手术20例,移植手术成功率为100%.20%小体积肝脏移植物的存活率为93.8%(＞14 d).组织学检查移植后的肝脏组织结构良好.移植术后72 h溴脱氧尿核苷染色阳性的肝细胞计数明显增多.结论 20%小体积大鼠肝脏移植物可启动完成移植后的肝脏再生.显微外科技术是移植模型成功的关键.该模型稳定性强,适合于部分肝脏移植领域的基础研究.     

大鼠同种异体喉移植模型的建立

应用现代显微外科手术，将双侧连接于体供喉的颈总动脉分别与受体一侧的颈总动脉和颈外静脉进行端－侧吻合，共对１３只大鼠实施喉异位移植。建立了同种异体喉移植的实验模型。移植动物全部存活，移植术后３天，移植物周围有纤维素粘粘连，７天后粘连加重，移植物表面附有灰白色的纤维结缔组织气管内     

三套管法建立大鼠原位全小肠移植模型

对于那些不能耐受肠外营养的终末期肠功能衰竭患者来说，小肠移植是最佳治疗方法。但是，由于肠道独特的生理特点使得小肠移植术后出现急慢性排斥、移植物抗宿主反应（GVHR）及感染等问题较其他实质脏器移植更为突出。大鼠原位小肠移植模型的制备，为深入研究上述问题提供了良机。以往报道的大鼠小肠移植模型由于显微外科操作复杂、手术成功率低等因素限制了其广泛应用。我们利用三袖套法吻合血管，简化了操作，提高了手术成功率。     

应用显微外科技术建立大鼠一期肝肾联合移植模型

目的 探讨应用显微外科技术建立稳定、可靠的大鼠一期肝、肾联合移植模型的手术技巧。方法 SD大鼠78只，39只作供体，39只作受体。供体经腹主动脉以4℃乳酸钠林格注射液同时对供肝和供肾进行原位灌洗。原位肝移植时除肝上下腔静脉缝合外，其余血管重建均采用袖套式吻合；肾移植采用将供肾的血管与受体的同名的血管作端端吻合的大鼠原位左肾移植。结果 共施行大鼠原位肝、肾联合移植手术39例，手术成功率为92．3％，术后最长存活的时间超过12个月。结论 娴熟的显微外科技术、细致的手术操作是建立肝、肾联合移植模型的先决条件。已建立的模型稳定性强、重复性好，适合于多器官移植中移植免疫的基础研究。     

大鼠的工作型与非工作型同种异体心脏移植模型比较

目的比较大鼠的工作型与非工作型同种异体心脏移植模型的优缺点。方法供者为Wistar大鼠（20只），受者为SD大鼠（20只），随机平均分为2组，建立工作型与非工作型腹部同种异体心脏移植模型。工作型移植模型为：供心肺动脉与受者左心房吻合，左心室血液经供心主动脉吻合口进入受者腹主动脉。非工作型移植模型为：供心肺动脉与受者下腔静脉端侧吻合，供心主动脉与受者腹主动脉端侧吻合。结果工作型与非工作型心脏移植模型手术成功率均为90％；总手术时间分别为（75．1±4．9）min和（85．8±7．4）mira术后恢复时间分别为（261．1±45．4）min和（387．8±39．6）min。工作型心脏移植模型总手术时间比非工作型约少10min，术后恢复时间明显缩短，差异有统计学意义。术后超声心动图显示工作型移植心有射血功能。结论大鼠的工作型腹部心脏移植模型总手术时间短、受者存活率高，更接近心脏的生理要求。     

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.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

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.     

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.     

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.     

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.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.