移植肾上尿路结石的腔内治疗

目的评估内镜治疗肾移植术后尿路结石的疗效。方法 5例肾移植并发上尿路结石患者接受了内镜手术治疗。其中肾结石2例,输尿管结石3例（其中输尿管膀胱吻合口狭窄并结石1例,金属支架结石2例）。结石最大直径11~52mm,发病时间为接受肾移植术后10个月~6年。结果 2例肾结石及1例金属支架结石患者接受钬激光经皮肾镜碎石取石术成功,2例输尿管结石行输尿管镜取石成功。无一例患者出现严重并发症。结论微创内镜手术在治疗移植肾术后并发尿路结石具有良好的效果。     

移植肾尿路结石的腔内治疗

目的探讨腔内治疗移植。肾尿路结石的效果和策略。方法采用腔内技术治疗13例移植。肾尿路结石，其中。肾结石3例，金属支架结石1例，输尿管结石9例，合并输尿管口狭窄2例。结石最大直径8～48mm，接受肾移植的时间1个月～8年。结果3例。肾结石和1例金属支架结石行经皮微造瘘输尿管镜取石术成功取石。4例输尿管结石行逆行输尿管镜取石治疗；3例行经皮顺行输尿管镜取石成功，其中1例合并移植输尿管口狭窄者同时行内切开取石；1例移植输尿管口狭窄合并下端结石者，改行开放手术；1例输尿管结石直接行体外冲击波碎石术2次后排净结石。术后随访1～8年，人肾存活均良好，12例患者。肾功能恢复正常，无结石复发。结论移植肾尿路结石处理应选择创伤小、效果好的腔内微创治疗，尽可能保护。肾功能。     

肠膀胱重建术后尿路结石的微创治疗(附4例报告)

目的：探讨肠膀胱重建术后尿路结石的微创治疗效果。方法：报告4例膀胱癌膀胱全切肠代膀胱术术后并发尿路结石患者的临床资料。结果：1例行经皮肾穿刺肾盂输尿管造影定位下体外冲击波碎石术，结石粉碎并排至结肠膀胱；1例行经皮肾镜碎石术；另2例行经尿道输尿管镜下钬激光碎石术，结石粉碎并取出。结论：肠膀胱重建术后尿结石的发生与尿路感染和手术操作等因素有关，对可控膀胱术后上尿路结石可实施经皮肾镜取石术或尿路造影定位下ESWL治疗，原位回肠代膀胱术后尿路结石可实施腔内碎石治疗。     

移植肾上尿路结石治疗方法的比较

目的比较不同的治疗方法对肾移植术后上尿路结石的疗效。方法收集我院1996至2002年间肾移植术后发生移植肾输尿管肾盂结石的患15例，其中肾结石4例，输尿管结石11例；体外震波碎石(ESWL)3例，输尿管镜取石7例，开放手术5例。结果5例开放手术术后均发生切口感染、尿外渗，其中2例有一过性肾功能不全．2例术后发生输尿管狭窄。3例体外震波碎石后都出现不同程度肾功能受损，严重血尿，2例碎石后产生石街。输尿管肾镜取石顺利完成，几乎无任何并发症出现。结论在严格掌握适应证的情况下，移植肾上尿路结石的治疗应首选经输尿管肾镜取石。     

尿流改道术后尿路结石的治疗

目的 探讨尿流改道术后尿路结石的治疗方法.方法 选取20例既往因膀胱癌接受尿流改道的尿路结石患者(肾结石6例,输尿管结石5例,储尿囊结石9例),接受个性化的治疗:其中经皮肾取石术8例,经皮肾顺行输尿管软镜碎石术3例,储尿囊流出道入路手术5例,经皮膀胱穿刺人路手术3例,开放取石1例.结果 手术时间60～130min,平均104min;术后结石清除率90％(18/20);术后发热4例(20％o),其中l例经皮肾镜技术(PCNL)术后液胸,行胸腔闭式引流.结论 针对尿流改道术后的尿路结石患者,采取个性化治疗方案,能够有效的清除尿路结石.     

肾移植术后上尿路梗阻14例临床诊治体会

目的探讨肾移植术后上尿路梗阻的诊断及处理。方法回顾总结2000—2006年我院1090例肾移植患者中的14例移植后上尿路梗阻患者，其中输尿管膀胱吻合口狭窄9例，6例行膀胱输尿管二次吻合手术，1例移植肾周感染输尿管末段坏死采用移植肾近端新鲜存活输尿管与自体输尿管吻合，1例采用膀胱肌瓣代移植输尿管，1例采用输尿管镜下气囊扩张后放置双J管。出血相关性梗阻、输尿管扭曲和输尿管结石所致梗阻5例，均行开放手术。结果14例肾移植术后上尿路梗阻患者中2例切除移植肾，其余各例患者经开放手术及腔镜处理均成功挽救移植肾功能。再次手术后随访0．5—1年，血肌酐68-155μmol／L，B超未见移植肾扩张积水加重。结论新上尿路梗阻是肾移植术后常见亦是较为棘手的外科并发症，多数和外科手术操作有关，可以通过提高手术技巧避免。一旦发生上尿路梗阻，应根据梗阻原因采取相应的治疗方法及时处理。     

肾移植术后上尿路结石个体化治疗策略

目的:探讨肾移植术后移植肾上尿路结石的个体化治疗策略。方法:回顾性分析2003年12月～2017年9月于我院泌尿与碎石中心治疗肾移植后移植肾上尿路结石10例患者的临床资料。其中男6例,女4例,平均年龄(42.1±8.6)岁。6例移植肾及输尿管上段结石,4例移植肾输尿管中下段结石。单发结石4例,多发结石6例,平均结石负荷(1.0±0.6)cm。所有患者均有不同程度肾积水,8例肾功能异常,4例尿路感染。结果:6例移植肾及输尿管上段结石患者中,1例行体外冲击波碎石(ESWL)成功;5例行经皮肾镜取石术(PCNL)成功。4例移植肾输尿管中下段结石患者,1例输尿管支架更换术中膀胱镜下活检钳取石成功;1例输尿管镜取石术(URS)成功;1例URS失败改PCNL成功;1例URS和PCNL处理结石均失败,留置造瘘、透析治疗。所有患者术后肾积水得到缓解,肾功能恢复,感染得到纠正。无患者出现术后发热。3例患者接受输血治疗。结论:肾移植结石患者情况特殊且病情相对复杂,术者应根据患者具体情况决定个体化的治疗策略,从处理结石的多种方法中选择最适合患者的手术方式和治疗方案。虽然清除结石是重要治疗目标,但应充分考虑患者身体耐受程度,不可盲目追求结石的清除效果。     

上尿路结石并发真菌感染的微创经皮肾镜治疗

目的：探讨输尿管镜和微创经皮肾镜探察取石术，以及术后局部灌注抗真菌药治疗上尿路结石并发真菌感染的有效性。方法：对49例上尿路结石并发真菌感染患者，采用输尿管镜探察和微创经皮肾镜取石术后经皮肾微造瘘管或输尿管外支架管灌洗抗真菌药治疗。结果：49例真菌感染均得到较好控制，尿液真菌培养阴性；45例结石取净，术后肾功能有不同程度的恢复，无一例出现大出血和真菌败血症。结论：输尿管镜探察和微创经皮肾镜取石术，以及术后局部灌注抗真菌药治疗上尿路结石并发真菌感染，是一种微创安全并能同时取石和控制感染的可靠方法。     

微创经皮肾取石术(附92例报告)

目的 探讨微创经皮肾取石术治疗上尿路结石的疗效。方法 从2000年1月至2004年11月期间采用微创经皮肾取石术共治疗92例上尿路结石病人，其中单发肾盂结石47例（51％），多发性结石37例（40％）。输尿管上段结石8例（9％），有开放手术史11例。结果 一期穿刺取石86例（95％），一期造瘘、二期取石5例（5％）。单通道取石79例，多通道取石13例。12例术后复查KUB仍有残石，结石清除率87％。手术时间平均140min，术中、术后有明显出血6例（6．5％），均经保守治疗治敷，平均住院时间9d。结论 微创经皮肾取石术治疗上尿路结石安全、有效的方法，对病人创伤小，术后恢复时间短。     

经皮肾穿刺微造瘘输尿管镜治疗上尿路结石

目的 探讨经皮肾穿刺微造瘘输尿管镜治疗上尿路结石的方法及疗效。方法 采用经皮肾穿刺微造瘘输尿管镜下气压弹道碎石处理肾和输尿管结石20例。结果 20例均一期手术取石，单通道取石18例。双通道取石2例；其中1次取石12例，2次取石7例，3次取石1例。15例结石全部取尽，余5例有少许残留。术后行ESWL，结石基本排出。平均手术时间85min，平均出血量50mL，术后平均住院时间8．5d。所有病例均无明显并发症。结论 经皮肾穿刺微造瘘取石术治疗肾及输尿管上段结石具有创伤小、并发症少、疗效好、恢复快等优点，值得推广应用。     

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 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.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.