内镜腔内手术胃内通道的猪模型的实验研究

目的 探讨内镜腔内手术的可行性。 方法 4只家猪经皮建立胃内通道。结果 4只家猪均很好地耐受了手术。术后开腹检查所有胃壁缝合处无渗漏及其它脏器损伤。建立胃内通道时间为15-30min。 结论 内镜腔内手术胃内通道在技术上是可行的。     

双镜联合技术在胃间质瘤治疗中的应用体会

目的:总结双镜联合技术治疗胃间质瘤的临床价值及经验体会。方法:回顾分析为27例患者行双镜联合胃间质瘤手术的临床资料。结果:6例行腹腔镜辅助内镜手术,内镜下切除肿瘤,腹腔镜辅助暴露内镜术野、监视并处理内镜手术穿孔、出血等并发症。肿瘤均属腔内型,最大径平均(2.2±0.8)cm,术中出血量平均(20.5±15.5)ml,手术时间平均(90.5±30.0)min,肛门排气时间平均(20.5±12.6)h,术后平均住院(4.5±1.8)d,1例术中胃壁穿孔,腹腔镜下胃壁浆肌层缝合加固,无肿瘤残留、其他并发症发生。21例行内镜辅助腹腔镜手术,腹腔镜下切除肿瘤及部分胃壁,内镜辅助定位并检查吻合口或胃壁闭合口。肿瘤属腔外型12例、壁间型5例、腔内型4例,最大径平均(4.5±2.2)cm,术中出血量平均(60.8±25.4)ml,手术时间平均(102.3±32.4)min,肛门排气时间平均(24.8±15.2)h,术后平均住院(5.2±2.0)d,无肿瘤残留及并发症发生。内镜辅助腹腔镜手术组肿瘤大小、术中出血量显著高于腹腔镜辅助内镜手术组(P0.05),其余指标未见统计学差异。结论:双镜联合技术具有微创优势,其中内镜辅助腹腔镜手术在胃间质瘤治疗中应用更为广泛。     

用SilsPort行单一切口腹腔镜胃内手术的可行性研究

目的探讨SilsPort行单一切口胃内手术的可行性、安全性与有效性。方法 6头家猪作为实验对象,将SilsPort经腹壁切口置入胃内。3头猪用超声刀切开胃后壁黏膜层,切开长度3 cm,3-0可吸收线间断缝合;另3头猪用抓钳抓取胃后壁组织,用直线切割吻合器切除。结果所有模拟操作均顺利完成,无明显术中出血与并发症。放置SilsPort所用时间为8~40 min,（16.2±12.2）min。3头猪用直线切割吻合器行模拟切除总手术时间分别为75、45、38 min;另3头猪用超声刀模拟切除缝合所用时间分别为80、85、70 min。术后活检见胃前壁缝合良好,胃内模拟切除部位缝合（或钉合）满意,局部无出血。结论用SilsPort进行胃内手术可行、安全,提供了将腹腔镜与器械置入胃内进行手术操作简便、稳定的平台。     

腔镜用缝合器在腹腔镜下胃空肠吻合中的应用

目的探讨腔镜用缝合器在腹腔镜下胃空肠吻合中应用的安全性与可行性。方法采用描述性病例系列研究方法, 回顾性分析2022年10月至2023年1月期间, 空军军医大学第二附属医院实施的5例腹腔镜远端胃癌根治术(Billroth Ⅱ+Braun吻合)中应用腔镜用缝合器缝合关闭胃空肠共同开口患者的病例资料。手术适应证为:(1)年龄为18～75岁;(2)术前病理确诊为胃腺癌;(3)术前临床分期为Ⅰ～Ⅲ期;(4)肿瘤位于胃中下1/3处, 可行根治性远端胃切除术;(5)既往无上腹部手术史(腹腔镜胆囊手术除外)。手术步骤如下:在进行胃-空肠吻合时, 先以腔镜下直线切割闭合器进行胃空肠侧侧吻合, 然后以腹腔用缝合器缝合关闭共同开口。在缝合关闭共同开口时, 采用自下而上、先内进内出后垂直褥式缝合的方法, 实现胃壁与空肠壁黏膜-黏膜、浆膜-浆膜完整内翻闭合;第一层缝合结束后, 再自上而下行浆肌层缝合包埋胃空肠共同开口。结果 5例患者均顺利完成了腹腔镜下利用腔镜用缝合器关闭胃空肠共同开口。手术时间(308.6±22.6)min;胃空肠吻合时间(15.4±3.1)min;术中出血量(34.0±10.8)ml。均无...     

胸腔镜下建立小型猪慢性心肌缺血模型

目的 探讨应用胸腔镜技术建立小型猪慢性心肌缺血模型的效果及可行性.方法 23只中国实验小型猪,雄性,体重20～30 kg,平均(29.3±4.3)kg,年龄8～11个月,平均(9.3±1.8)个月.在完全胸腔镜下将Ameroid环置于回旋支主干,术前及术后6周分别进行冠状动脉造影及超声心动图检查.结果 23只猪中20只顺利完成手术,手术时间25～125 min,平均(46±9)min.术中出血量30～60 ml,平均(55±12)ml.术后6周内因肺部感染、二次造影时心律失常及麻醉意外死亡3只.术后6周行冠状动脉造影显示,7只动物回旋支完全闭塞,13只狭窄大于85%.超声心动图心肌收缩及舒张功能明显下降,术前射血分数(65.0±6.3)%,短轴缩短率(36.2±4.3)%;术后6周射血分数(41.0±9.3)%,短轴缩短率(34.2±2.3)%,均低于术前水平(P<0.05).结论 应用胸腔镜技术放置Ameroid环可以有效建立小型猪慢性心肌缺血模型.     

完全机器人手工缝合消化道重建技术在全胃切除术中的应用

目的:探讨完全达芬奇机器人手工缝合消化道重建技术在全胃切除术中应用的可行性和安全性.方法:回顾性分析2015年7月～2018年6月东部战区总医院胃癌患者行全胃根治性切除术的临床资料.根据手术方式分为完全机器人全胃切除(Robot-assisted total gastrectomy,RATG)组、腹腔镜辅助全胃切除(Laparoscopic assisted total gastrectomy,LATG)组.RATG组行机器人镜下腔内手工缝合消化道重建,采用Uncut Roux-en-Y重建方案;LATG组行体外吻合器消化道重建,采用传统Roux-en-Y重建方案.观察分析两组患者手术指标、术后康复指标、标本肿瘤学指标、经济学指标及术后并发症情况.结果:两组100例患者均顺利完成手术.RATG组较LATG组腹部切口短[(3.95±0.64)cm Vs(10.38±1.79)cm,P<0.001],术中出血量少[(57.10±20.55)ml Vs(98.20±?28.44)ml,P<0.001],但手术时间长[(201.66±16.59)min Vs(156.14±16.69)min,P<0.001],消化道重建耗时长[(56.70±8.78)min Vs(36.60±8.17)min,P<0.001],住院费用高[(8.55±1.78)万元Vs(6.39±0.86)万元,P<0.001].RATG组较LATG组术后住院时间短[(5.84±4.76)d Vs(6.98±4.31)d,P=0.213],但差异无统计学意义.两组患者在术后视觉疼痛评分(VAS)、术后TNM分期、淋巴结清扫数目、阳性淋巴数目、术后首次排气时间、首次下床活动时间、首次进食流质时间及术后并发症方面的差异均无统计学意义(P>0.05).结论:完全达芬奇机器人手工缝合消化道重建技术在全胃切除术中的应用是安全、可行的.     

猪主动脉腔内隔绝术经腹腔入路与腹膜外入路的效果比较

目的:比较经腹腔入路与腹膜外入路在解剖猪腹主动脉作为胸主动脉血管腔内隔绝术导入动脉的效果.方法:12头实验猪随机分为腹腔组和腹膜外组,每组6头,分别经腹腔入路和腹膜外入路两种方法解剖腹主动脉,并在胸主动脉腔内植入移植物.结果:两种入路均可暴露腹主动脉.腹腔组1头因肠缺血死亡,1头损伤膀胱;腹膜外组2头损伤腹膜.平均手术时间腹膜外组为(20.3±2.1)min,腹腔组为(26.2±7.6)min.术后排便时间腹膜外组为(18.8±12.4)h,腹腔组为(39.8±11.6)h.术后第3个月腹膜外组体质量为(44.4±2.4)kg,腹腔组为(39.4±1.7)kg.结论:经腹膜外入路解剖猪腹主动脉行血管腔内隔绝术手术时间更短,消化道功能恢复早,术后体质量增加明显,比经腹腔入路更为安全、有效.     

经自然腔道内镜手术在泌尿外科领域的应用

经自然腔道内镜手术(NOTES)[1]是指经胃、结肠、阴道、膀胱等人体自然开口与管腔,向体腔内置入内镜器械进行操作的手术类型.按是否建立辅助经皮工作通道可将NOTES分为混合经自然腔道内镜手术和完全经自然腔道内镜手术2大类.混合经自然腔道内镜手术需经皮途径设立辅助工作通道,手术主要操作则在自然腔道工作通道中完成.目前以经脐入路结合经自然腔道内镜手术和机器人辅助经自然腔道内镜手术(R-NOTES)多见.     

Cuff 套管技术在同系大鼠肺移植中的应用

目的 建立同系大鼠原位肺移植模型,评价Cuff 套管技术应用效果.方法 采取两名手术者同时、分别行供受体手术的方法,行左侧同系原位大鼠肺移植22例,肺动脉、肺静脉、主支气管吻合均采用非缝合的Cuff套管技术,评价其可行性和可靠性.结果 移植手术成功率90.9%(20/22),移植物缺血时间、热缺血时间和总的手术时间分别为(42.5±2.3)min,(17.1±3.6)min和(68.7±5.1)min.同系大鼠移植术后3周以内(12/22)通气和血流灌注良好,手术后6个月(3/22)、9个月(3/22)、12个月后(2/22)移植肺显示通气不良但吻合口开放.结论 大鼠原位肺移植模型采用非缝合的Cuff套管技术行支气管和血管吻合简便、快速和可靠,支气管吻合后能够保持较长时间的管腔开放.     

腹腔镜胃间质瘤切除术手工缝合胃创面30例报告

目的:探讨腹腔镜胃间质瘤切除术后手工缝合胃壁的临床效果。方法:回顾分析2011年1月至2013年12月为30例胃原发间质瘤患者行腹腔镜手工缝合手术的临床资料。6例患者肿瘤直径≤2.0 cm,19例为2.1~5.0 cm,5例5.0 cm。肿瘤位于贲门部2例、胃底8例、胃体前壁4例、胃体后壁5例、胃窦前壁5例、胃窦后壁2例、胃小弯侧4例。结果:30例手术均获成功。手术时间平均(90.0±20.37)min,术中出血量平均(15.0±12.85)ml;术后肠道功能恢复时间平均(36.0±9.44)h,术后恢复进食时间平均(3.0±1.21)d,无出血、胃瘘、腹腔感染等并发症发生。术后平均住院(8.0±1.61)d。术后随访6~12个月,无肿瘤复发及转移。结论:腹腔镜下采用手工缝合的方法治疗胃间质瘤体现了腹腔镜手术的优点。对于特殊部位的间质瘤可行腹腔镜手术。     

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.     

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.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.