腹腔镜辅助下胃癌D2根治性远端胃大部切除术安全性与有效性的系统评价

目的 评价腹腔镜辅助下胃癌D2根治性远端胃大部分切除术的安全性与有效性.方法 检索Pubmed、Medline、EMBASE和中国生物医学数据库(CBM)2001年1月至2010年2月间发表的D2根治性远端胃大部分切除术治疗胃癌的对照试验研究,用Revman 5.0统计软件进行分析.结果 共纳入7个对照试验,其中1项研究为随机对照试验,6项为非随机对照研究.腹腔镜辅助远端胃大部分切除组(LADG)与开腹远端胃大部切除术(ODG组)相比,术中出血量少[加权均数差(WMD)=-132.04,95% CI:-207.32～-56.77],术后第1次排气时间早(WMD=-0.82,95% CI:-1.20～-0.45),术后并发症发生率低[相对危险度(OR)=0.45,95%CI:0.26～0.78],术后住院时间短(WMD=-3.63,95%CI:-4.19～-3.07),清扫的淋巴结数目多(WMD=1.93,95%CI:0.36～3.50);但术后复发率、转移率和近期(3年内)生存率差异无统计学意义(P＞0.05).结论 腹腔镜辅助下胃癌D2根治性远端胃大部分切除术的短期效果优于开腹手术.     

新辅助放化疗后行腹腔镜手术与开腹手术治疗进展期直肠癌的meta分析

目的:应用meta分析评价新辅助放化疗后行腹腔镜手术与开腹手术治疗进展期直肠癌的可行性及疗效。方法:利用计算机检索Pub Med、Embase、Cochrane Library等数据库,检索新辅助放化疗后行腹腔镜手术对比开腹手术治疗进展期直肠癌的英文文章,采用Rev Man 5.3软件进行meta分析。结果:共纳入2篇随机对照试验、7篇非随机对照试验,共1 338例患者,其中腹腔镜组691例,开腹组647例,meta分析结果显示,新辅助放化疗后,两组患者环周切缘阳性(OR=1.24,95%CI:0.74~2.08,P=0.42)、淋巴结摘除数量(WMD=-0.35,95%CI:-1.48~0.78,P=0.54)差异均无统计学意义;腹腔镜组手术时间长于开腹组(WMD=26.26,95%CI:4.59~47.92,P=0.02),但术中出血量(WMD=-46.48,95%CI:-72.85~-20.11,P=0.0006)、术后住院时间(WMD=-1.80,95%CI:-2.85~-0.74,P=0.0009)、术后并发症(OR=0.77,95%CI:0.60~0.99,P=0.04)均少于开腹组;二次手术(OR=1.30,95%CI:0.61~2.77,P=0.49)两组差异无统计学意义。结论:短期疗效、病理学结果显示,新辅助放化疗后行腹腔镜手术与传统开腹手术治疗进展期直肠癌是安全、有效的。     

腹腔镜Nissen胃底折叠术治疗胃食管返流病的长期效果

目的:评价腹腔镜Nissen胃底折叠术(laparoscopic Nissen fundoplication,LNF)治疗胃食管返流病的长期效果。方法:从MEDLINE、EMBASE、中国生物医学数据库(CBM)及Cochrane试验注册中心检索纳入了1991年到2007年10月发表的LNF治疗返流性食管炎的随机对照实验,并对纳入研究的方法学质量(随机方法、分配隐藏、盲法)进行评价,最后用Rev-Man4.2.9软件进行分析。结果:纳入4个随机对照实验(RCT),包括440例患者,纳入随访研究共387例。术后主观结果如满意度[OR0.5095%CI(0.25,1.00)]、术后抑酸药物的使用[OR0.4595%CI(0.08,2.53)]、返酸和烧心症状差异无统计学意义,吞咽困难LNF发生率高于传统胃底折叠术(conventional Nissen fundoplicationm,CNF)[OR4.1695%CI(1.51,11.50)]。客观结果如再手术率[OR1.7795%CI0.78,4.72)]、食管测压和24h pH检测两组间差异无统计学意义。结论:本研究中LNF治疗胃食管返流病的长期效果和传统胃底折叠术差异无统计学意义,但LNF术后吞咽困难发生率可能较高。     

腹腔镜胃底折叠术治疗胃食管反流性疾病临床分析

目的　探讨腹腔镜胃底折叠术治疗胃食管反流性疾病的可行性及安全性。　方法　回顾性分析 2 0 0 1年 6月至 2 0 0 1年 10月对 5例行腹腔镜胃底折叠术的胃食管反流性疾病的临床资料。　结果　 3例行腹腔镜Nissen胃底折叠术 ,2例腹腔镜Toupet胃底折叠术。术后症状完全缓解。食道下段压力由 (7 32± 1 34)mmHg提高到 (18 2 0± 3 4 3)mmHg(t=12 2 3,P <0 0 1) ,2 4 -小时PH值监测评分由183 36± 96 76降低到 8 0 4± 2 12 (t=8 4 7,P <0 0 1) ,较手术前有明显改善 ,并达到正常范围。无手术并发症 ,无中转开腹及死亡病例。　结论　对于严重的胃食管反流性疾病 ,腹腔镜胃底折叠术是一种安全、有效的治疗方法。     

腹腔镜与开放式无张力疝修补术治疗成人复发性腹股沟疝疗效Meta分析

目的 评价腹腔镜与开放式无张力疝修补术治疗成人复发性腹股沟疝的临床疗效。 方法 计算机检索PubMed、EMbase、Cochrane Library、Web of Science、中国生物医学文献数据库、中国学术期刊网全文数据库、中文科技期刊数据库和万方数据库,同时辅以其他检索。检索时间均从建库至2014年5月,语种不限。收集所有比较腹腔镜与开放式无张力疝修补术治疗成人复发性腹股沟疝的随机对照试验（RCTs）。由两名评价员独立按照纳入标准提取数据并交叉核对,采用Cochrane协作网推荐软件RevMan 5.2版进行统计分析。结果 最终纳入11个RCT,共1039例病人。Meta分析结果显示：与开放无张力组相比,腹腔镜技术在慢性疼痛（OR=0.40,95%CI：0.20~0.82,P=0.01）、切口感染率（OR=0.28,95%CI：0.10~0.81,P=0.02）、术后住院时间（国外：MD=-4.54,95%CI：-5.59~-3.49,P<0.00001;国内：MD=-2.46,95%CI：-2.83~-2.08,P<0.00001）和手术时间（MD=16.74,95%CI：14.69~18.80,P<0.00001）方面差异有统计学意义,而在术后再复发率（OR=0.73,95%CI：0.44~1.20,P=0.22）、急性疼痛（OR=0.74,95%CI：0.14~3.76,P=0.71）、血肿或血清肿（OR=0.73,95%CI：0.48~1.11,P=0.14）与尿潴留（OR=0.97,95%CI：0.46~2.07,P=0.94）方面差异无统计学意义。结论 与开放无张力手术相比,腹腔镜手术不可以降低术后再复发率但可以降低术后慢性疼痛与切口感染发生率;可以缩短术后住院时间但手术时间较长。两组在急性疼痛、血肿或血清肿与尿潴留方面的差异均无统计学意义。     

腹腔镜和机器人Roux-en-Y胃旁路术治疗病态肥胖有效性和安全性的meta分析

目的系统评价机器人和腹腔镜Roux-en-Y胃旁路术(RYGB)治疗病态肥胖的安全性和有效性。方法计算机检索PubMed、Embase、Cochrane Library、万方数据、CBM、CNKI等数据库,收集机器人和腹腔镜RYGB治疗病态肥胖的相关研究。由2名研究者独立进行文献筛选和数据提取,采用R软件进行统计学分析。结果共有19篇文献177 766例肥胖患者进行了RYGB,其中172 234例进行了腹腔镜RYGB(腹腔镜组)、5 532例患者进行了机器人RYGB(机器人组)。与腹腔镜组比较,机器人组手术时间更长[MD=27.84,95%CI(12.85,42.83)]、死亡率更高[OR=2.05,95%CI(1.03,4.08)];2组间的住院时间[MD=-0.01,95%CI(-0.24,0.23)]、术中失血量[MD=-2.01,95%CI(-4.80,0.78)]、术中中转率[OR=1.00,95%CI(0.16,6.33)]、术后30 d再手术率[OR=1.34,95%CI(0.38,4.74)]、术后30 d再入院率[OR=0.86,95%CI(0.47,1.58)]、总并发症率[OR=0.93,95%CI(0.75,1.15)]及具体并发症如吻合口漏[OR=0.92,95%CI(0.38,2.19)]、伤口感染[OR=1.17,95%CI(0.45,3.08)]、肺栓塞[OR=1.97,95%CI(0.93,4.17)]、吻合口狭窄[OR=1.01,95%CI(0.53,1.93)]、吻合口边缘溃疡[OR=1.30,95%CI(0.61,2.76)]方面比较差异均无统计学意义。结论机器人RYGB是一种安全、有效的手术方式,但其在减少并发症及术后疗效方面并未优于腹腔镜RYGB。     

腹腔镜辅助下胃癌D2根治性远端胃大部切除术安全性与有效性的系统评价

目的 评价腹腔镜辅助下胃癌D2根治性远端胃大部分切除术的安全性与有效性.方法 检索Pubmed、Medline、EMBASE和中国生物医学数据库（CBM）2001年1月至2010年2月间发表的D2根治性远端胃大部分切除术治疗胃癌的对照试验研究,用Revman 5.0统计软件进行分析.结果 共纳入7个对照试验,其中1项研究为随机对照试验,6项为非随机对照研究.腹腔镜辅助远端胃大部分切除组（LADG）与开腹远端胃大部切除术（ODG组）相比,术中出血量少[加权均数差（WMD）=-132.04,95% CI：-207.32～-56.77],术后第1次排气时间早（WMD=-0.82,95% CI：-1.20～-0.45）,术后并发症发生率低[相对危险度（OR）=0.45,95%CI：0.26～0.78],术后住院时间短（WMD=-3.63,95%CI：-4.19～-3.07）,清扫的淋巴结数目多（WMD=1.93,95%CI：0.36～3.50） 但术后复发率、转移率和近期（3年内）生存率差异无统计学意义（P＞0.05）.结论 腹腔镜辅助下胃癌D2根治性远端胃大部分切除术的短期效果优于开腹手术.     

机器人与腹腔镜手术治疗胃癌的围手术期效果Meta分析

目的:系统性分析达芬奇机器人胃切除术(robotic gastrectomy,RG)与腹腔镜胃切除术(laparoscopic gastrectomy,LG)治疗胃癌的围手术期效果。方法:计算机检索Pub Med、Embase、Cochrane Library、中国知网、中国生物医学文献数据库、万方数字化期刊全文数据库及中文科技期刊全文数据库,收集2017年12月前发表的关于比较RG与LG治疗胃癌围手术期效果的中文文献与英文文献,使用Rev Man 5.3软件进行Meta分析。结果:最终纳入30项研究,共9 889例患者,其中RG组2 950例,LG组6 939例。Meta分析结果显示,与LG组相比,RG组手术时间长(MD=38.76,95%CI=30.45~47.06,P0.05),术中出血量少(MD=-37.25,95%CI=-49.20~-25.31,P0.05),淋巴结清扫数量多(MD=2.19,95%CI=0.59~3.80,P0.05),术后住院时间、首次排气时间、首次进食时间短(MD=-0.77,95%CI=-1.25~-0.29;MD=-0.13,95%CI=-0.24~-0.03;MD=-0.17,95%CI=-0.30~-0.04;P0.05),两组近端切缘距离、远端切缘距离、术后并发症发生率、中转率及病死率差异无统计学意义(MD=0.02,95%CI=-0.25~0.29;MD=0.17,95%CI=-0.31~0.65;OR=0.90,95%CI=0.76~1.07;OR=2.00,95%CI=0.27~14.77;OR=1.07,95%CI=0.63~1.81;P0.05)。结论:与LG相比,RG治疗胃癌安全、可行,可取得与LG相近或更好的围手术期效果。     

老年人腹股沟疝腹腔镜与开腹手术的疗效及安全性评价:Meta分析

目的分析腹腔镜与开腹手术对于治疗老年人腹股沟疝的疗效与安全性。方法检索万方、中国知网、PubMed、EMBASE、Cochrane Library等电子数据库,并人工检索相关电子期刊,针对筛选出的临床随机对照试验,运用Meta分析的方法综合比较相关指标并做综合评价。结果最终纳入8篇文献,共计818例老年病人。腹腔镜组与开腹组相比,在手术时间上差异无统计学意义(SMD=0.00,95%CI:-1.41~1.41,P=0.99);但住院时间更短(SMD=-1.64,95%CI:-2.06~-1.22,P0.01);并发症数量也较少(RR=0.31,95%CI:0.19~0.50,P0.01);治疗有效率更高(OR=3.17,95%CI:1.06~9.49,P=0.04)。结论腹腔镜治疗老年人腹股沟疝具有明显优势,应成为主要术式。     

达芬奇机器人与腹腔镜手术治疗胃癌疗效比较的Meta分析

目的:系统评价达芬奇机器人胃癌手术的有效性、安全性与近远期疗效。方法:检索国内外数据库,收集比较达芬奇机器人胃癌手术与传统腹腔镜胃癌手术的文献,对获得的数据用Rev Man5.2软件进行Meta分析。结果:纳入17篇文献,共5787例患者,其中机器人手术1676例,传统腹腔镜手术4111例。Meta分析结果显示,与传统腹腔镜手术比较,机器人手术所用时间延长(WMD=43.51,95%CI=34.14~52.88,P0.05)、术中失血量减少(WMD=-30.17,95%CI=-42.83~-17.51,P0.05)、淋巴结清扫数目增加(WMD=1.95,95%CI=0.07~3.84,P0.05)、首次进食时间提前(WMD=-0.22,95%CI=-0.32~-0.12,P0.05),而其他指标包括近远端切缘距离、R0切除率、中转率、术后首次排气时间、术后住院时间、并发症发生率、病死率、3年生存率均相似(均P0.05)。结论:达芬奇机器人胃癌手术安全、有效,且有较好的近远期疗效。     

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.     

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.