异种膀胱无细胞基质替代尿道的研究

目的探讨异种膀胱无细胞基质(ACM)管状替代尿道的可行性。方法19只成年雄性新西兰白兔分成3组：A组3只，为假手术对照组；B组10只，切除一段1．0cm尿道；C组6只，切除一段3．5～4．0cm尿道，之后应用已经事先制备好的异种膀胱ACM制成相当长度的管状替代被切除的尿道。术后1、2、4、8、16周动态观察替代尿道的尿道上皮、平滑肌和血管的再生情况。结果所有实验动物在术后7d拔除尿管后都恢复了自主排尿，没有排斥、尿瘘、感染等并发症发生。组织学检查显示实验组术后2周尿道上皮再生良好，4周完全覆盖尿道内腔，术后8周平滑肌见于近吻合口处，平滑肌生长缓慢，观察期内未能覆盖全长尿道。尿道造影未见明显尿道狭窄和憩室。结论异种膀胱ACM是一种良好的尿道修复和替代的材料。     

腔镜下钬激光内切开加定期尿道扩张治疗男性尿道狭窄及闭锁

目的探讨腔镜下钬激光内切开治疗男性尿道狭窄及闭锁的效果及安全性。方法我院2007年4月～2009年11月收治男性尿道狭窄或闭锁病人17例,狭窄段长0.5～3.0cm,平均1.4cm,采用腔镜下钬激光狭窄段内切开治疗。术后留置尿管2～4周。拔除尿管后根据随访排尿状况定期作尿道扩张。结果 17例病例均取得手术成功,手术时间30～90min,平均40min,术后排尿显著改善,最大尿流率(Qmax)由术前平均6.5(2.8～11.5)ml/s提高到术后20.4(16.6～25.3)ml/s,无尿失禁、阳痿、尿瘘并发症。术后随访3～18个月,均排尿良好,无再狭窄发生,B超检查剩余尿<20ml。结论腔镜下钬激光内切开加定期尿道扩张治疗男性尿道狭窄及闭锁安全有效,近期治疗效果良好,手术创伤小,并发症少,值得推广应用。     

脱细胞尿道细胞外基质修复尿道缺损的临床研究

目的 总结新型替代材料修复尿道缺损的临床经验.方法 采用组织工程学材料脱细胞尿道细胞外基质(ECM)修复男性长段尿道缺损8例.患者平均年龄56岁.病程3～60个月,平均16.7个月.其中陈旧性前尿道狭窄4例、球部尿道狭窄2例、狭窄段从前尿道延伸到后尿道2例.狭窄长度3～8 cm,平均5 cm.结果 8例随访3～21个月,平均12.5个月.术后6周拔除尿管2例,8周拔管6例.无狭窄、尿瘘,排尿通畅7例,1例排尿不畅者定期行尿道扩张.术后8周尿道造影显示尿道通畅,未见吻合口狭窄.结论 脱细胞尿道细胞外基质为机体提供了良好的供宿主组织爬行替代的框架,在修补后可有效地与宿主组织融合,修补后的尿道愈合良好.     

口腔内黏膜尿道成形治疗前尿道狭窄10年经验总结

目的 探讨口腔内黏膜尿道成形治疗尿道狭窄的长期效果. 方法 2001年1月至2010年12月,应用口腔内黏膜(颊黏膜和舌黏膜)尿道成形治疗前尿道狭窄255例.尿道狭窄段长度3 ～18 cm,平均6 cm.尿道成形采用保留原尿道板的扩大尿道成形术或埋藏黏膜条背侧替代尿道成形术.对49例尿道狭窄段≥8 cm者采取双侧颊黏膜拼接、颊粘膜与舌黏膜拼接或双侧连续长条舌黏膜尿道成形. 结果 术后随访8 ～120个月,平均37个月.230例患者排尿通畅,尿线粗,最大尿流率为16～51 ml/s,平均26 ml/s.尿道造影显示重建段尿道管腔通畅.总成功率90.2％.25例患者于术后1年内发生并发症,其中尿道再次狭窄17例,尿道皮肤瘘8例.17例尿道再狭窄患者中15例再次行口腔内黏膜尿道成形,2例吻合口狭窄行尿道内切开,术后排尿通畅;8例尿道皮肤瘘均接受尿瘘修补术后治愈. 结论 口腔颊黏膜和舌黏膜均是良好的尿道替代物,舌黏膜取材较颊黏膜更为便利;口腔内多种黏膜的组合移植重建尿道是治疗长段前尿道狭窄( ≥8 cm)的有效方法.     

结肠黏膜重建尿道治疗复杂性超长段尿道狭窄

目的:探讨结肠黏膜重建尿道治疗复杂性超长段尿道狭窄的应用价值与疗效.方法:对既往已有平均2.5次不成功的尿道修复史的35例患者,采用结肠黏膜一期尿道成形术,治疗其复杂性超长段尿道狭窄.所用结肠黏膜重建的尿道长10～20cm,平均14.6cm.术后分别行尿道造影,检测尿流率,部分患者行尿道镜检查.结果:患者术后随访3～60个月,平均28.5个月.31例术后排尿通畅,最大尿流率大于15 ml/s.1例因结肠黏膜新尿道与前列腺部尿道吻合区血供较差,术后继发尿道狭窄;1例在术后3个月并发尿道外口狭窄,经手术矫正后排尿通畅;2例分别在术后46,20个月时发生与重建尿道无关的球膜部尿道狭窄,采用口腔黏膜尿道成形术后排尿通畅.结论:利用结肠黏膜重建尿道治疗复杂性超长段尿道狭窄或闭锁,是一种可行而有效的方法,尤其是适合在较多常规方法治疗失败者.     

结肠粘膜重建尿道治疗复杂性尿道狭窄的探讨

目的 探讨结肠粘膜替代尿道治疗复杂性较长段尿道狭窄或闭锁的可能性。方法 采用结肠粘膜重建尿道一期尿道成形术治疗6例复杂性较长段尿道狭窄，患者术前有平均3次不成功的尿道修复史，用结肠粘膜重建的尿道长10－15cm，平均12.7cm。术后随访时分别行逆行尿道造影，尿道镜和尿流率检查。结果 术后随访3－14个月，平均7.8个月。1例在术后3个月并发尿道外口狭窄性，经手术矫正后排尿通畅，术后1年随访时最大尿流率28.7ml/s。余5例术后排尿通畅，最大尿流率大于15ml/s。术后6个月4例经尿道镜检查，肉眼较难将尿道的结肠粘膜与正常的尿道粘膜相区别。结论 结肠粘膜重建尿道治疗较长段尿道狭窄或闭锁是一种可行而有效的方法，适合阴茎皮肤或膀胱粘膜利用有困难时的尿道重建。     

输尿管镜联合S形尿道扩张器在男性尿道狭窄治疗中的应用

目的探讨输尿管镜联合S形尿道扩张器在男性尿道狭窄治疗中的临床价值。方法采用输尿管硬镜直视下置入斑马导丝,用套入法通过S形尿道扩张器进行尿道扩张并留置相应尿管治疗男性尿道狭窄27例,术后留置尿管1～4周,定期门诊随访并行尿道扩张,观察患者排尿情况。结果全部病例拔除尿管后排尿症状明显改善,术后尿道扩张期间排尿通畅,无并发症出现。结论输尿管镜联合S形尿道扩张器在男性尿道狭窄尿道扩张中具有一定优势,选择合适的病例采用此法治疗尿道狭窄是安全有效的。     

前尿道替代膜部尿道治疗男性后尿道狭窄52例报告

目的：探讨长段后尿道狭窄手术治疗方法。方法：同顾性总结前尿道替代膜部尿道端端吻合治疗狭窄段〉2cm的后尿道狭窄患者52例。结果：一次手术成功49例,成功率94．2％,3例术后尿线细,排尿不畅经内窥镜切除0．3～0．5cm瘢痕后排尿通畅。随访5～20年,全部排尿通畅,最大尿流率20～25ml／s,平均22ml／s。结论：切除狭窄段瘢痕前尿道替代膜部尿道端一端吻合治疗后尿道狭窄成功率高,远期效果好。术中彻底切除瘢痕,满意的无张力外翻端一端吻合及术后预防感染是手术成功的关键。     

睾丸鞘膜移植治疗前尿道长段狭窄的远期疗效分析

目的 探讨睾丸鞘膜替代尿道治疗前尿道长段狭窄的方法.方法 40例前尿道长段狭窄患者采用带蒂的睾丸鞘膜代尿道一期尿道成形术治疗,术后随访时分别行逆行尿道造影和尿流率检查.结果 本组40例手术一次性成功,术后3周拔除尿管,平均随访24个月,术后测定平均最大尿流率明显高于术前.结论 带蒂睾丸鞘膜可作为良好的尿道替代物,手术创伤小,取材方便,组织修复快,对长段前尿道狭窄是一种行之有效的方法.     

游离黏膜尿道成形治疗硬化性苔藓样病所致尿道狭窄的疗效观察

目的 提高对硬化性苔藓样病( lichen sclerosus,LS)导致尿道狭窄的认识,观察游离黏膜尿道成形治疗LS所致尿道狭窄的疗效. 方法 2007年1月-2010年12月收治LS所致前尿道狭窄患者36例,年龄27～75岁,平均41岁.尿道狭窄段长5.0 ～20.0 cm,平均11.5 cm.根据尿道狭窄段长短和严重程度选择不同的黏膜组织,其中行口腔内黏膜(舌、颊黏膜)尿道成形27例,结肠黏膜尿道成形8例,另1例老年患者行前尿道劈开.在行尿道重建术前对病变累及的阴茎头、尿道口、尿道行病理学检查. 结果 36例患者术后3周拔除导尿管,排尿通畅;活检结果提示上皮基底部特征性病变,过度角化,上皮层变薄,淋巴细胞浸润等.术后随访6 ～ 50个月,平均22个月.出现尿道外口狭窄3例(8.3％),其中口腔内黏膜尿道成形者2例,结肠黏膜重建尿道者1例,行尿道外口切开后排尿通畅.余患者术后排尿通畅,最大尿流率17.2～47.0 ml/s,平均23.4 ml/s. 结论 采用游离黏膜尿道成形治疗LS所致尿道狭窄疗效较好,但需密切随访,因病变迁延可致尿道再狭窄,尤其是尿道口再狭窄.     

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.     

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.     

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.