经交通支腔内血管成形术治疗膝下动脉闭塞病变

目的评价经交通支血管腔内成形术治疗膝下动脉闭塞性病变的可行性与疗效。方法回顾性分析7例因常规腔内成形术失败而接受经交通支血管腔内成形术的膝下动脉闭塞病变患者的临床及影像资料,比较术前与术后踝-肱指数(ABI)变化,观察患者临床症状改善、术后并发症及随访情况。结果对7例均成功经膝下交通支逆向开通膝下病变血管。术后第3天ABI(0.86±0.10)明显高于术前(0.47±0.17),差异有统计学意义(P0.05)。术后患者静息痛症状均消失,围手术期无严重并发症。随访1~21个月[平均(8.43±7.35)个月],5例患者临床症状较术前明显改善,2例患者术后15、21个月时因静息痛再次接受腔内治疗。3例足部溃疡或坏疽的患者伤口均于随访期间愈合,所有患者均无需截肢。结论对于远端无明显流出道的膝下动脉闭塞病变患者,经交通支血管腔内成形术切实可行。     

膝下动脉狭窄或闭塞血管腔内成形术的治疗

目的探讨血管腔内成形术(PTA)治疗膝下动脉狭窄或闭塞的临床疗效。方法回顾性分析2007年6月至2009年7月我科采用PTA治疗的34例(38条患肢)膝下动脉狭窄或闭塞患者的临床资料。结果 35条患肢PTA治疗成功,技术成功率为92%(35/38),平均随访8(3～18)个月,踝肱指数(ABI)由术前的0.41±0.12上升至0.82±0.05(P0.01),总的肢体保全率为91.4%。无住院死亡,并发症发生率为13%(5/38)。结论 PTA治疗膝下动脉狭窄或闭塞短期内具有较好的临床疗效,可以明显减少截肢率,是一种治疗膝下动脉病变至下肢缺血有效且安全的方法。     

腔内介入治疗膝下动脉缺血性疾病

目的 回顾性分析血管腔内介入治疗膝下动脉缺血性疾病的疗效,初步总结其技术要点、主要并发症防治与应用价值.方法 对2004年11月至2007年7月期间收治的60例(65条肢体)膝下动脉缺血性疾病的患者行膝下病变段动脉球囊扩张(percutaneous transluminal angioplasty,PTA)和/或支架植入(stenting)治疗,观察症状的改善,踝肱指数(ankle/brachial index,ABI)的变化,保肢率以及近期通畅率.结果 60例患者(65条肢体)中,技术成功51例,成功率83.3%;临床成功53例,成功率88.3%.症状完全缓解40例(66.7%),部分缓解13例(21.7%),无改善7例(11.6%);ABI从术前0.40±0.18增加到术后0.91±0.22,两者差异有统计学意义(P＜0.01).2例膝下截肢,4例足趾截趾,出院时保肢率为91%.随访54例,随访时间10 d至30个月,平均(14.5±1.2)个月.2例膝上截肢,2例膝下截肢,2例足趾截趾,保肢率88.9%(48例/54例);症状复发5例,复发率9.2%,血管再闭塞或再狭窄10例,通畅率81.5%,1年累积通畅率为57.3%.结论 腔内介入治疗膝下动脉缺血性疾病安全、可行,近期疗效确切,是该类疾病重要的治疗选择.     

膝下动脉闭塞的腔内治疗

目的 总结40例膝下动脉闭塞腔内治疗的疗效.方法 2006年11月至2007年12月期间40例下肢膝下动脉闭寨患者41条患肢行44次腔内治疗,平均年龄(76±6)岁,治疗前踝/肱指数(ankle brachial index,ABI)足背动脉0.39±0.20,胫后动脉0.39±0.23,严重下肢缺血(criticallimb ischemia,CLI)占80.49%(33/41).结果 治疗后ABI足背动脉提高了 0.43±0.22(P<0.01),胫后动脉提高了0.43±0.25(P<0.01).35例36条肢体获随访,平均随访(6±3)个月,Fontaine Ⅰ级与Fontaine Ⅱ A级肢体共计28条,占77.78%,CLI降至19.44%(7/36),显著低于治疗前(P<0.01),随访时ABI足背动脉0.63±0.22,胫后动脉0.56±0.22,与治疗前相比差异均有统计学意义.治疗后及随访时患肢的足背动脉与胫后动脉ABI比较差异无统计学意义.全组围手术期截肢率为0,围手术期死亡率2.5%,总死亡率15%,保肢率100%.结论 膝下动脉腔内治疗后疗效和平均随访6个月的疗效均令人满意;膝下动脉腔内治疗可以成为膝下动脉闭塞治疗的首选方法.     

膝下动脉腔内成形术治疗严重下肢缺血

目的观察膝下动脉腔内成形术治疗严重下肢缺血的疗效。方法对2004年10月至2006年5月采用腔内成形术治疗的41例患者共48条患肢的资料进行回顾性分析。26条患肢有静息痛(54.2%);9条患肢发生足部溃疡(18.7%),13条患肢合并有足趾或足部组织坏疽(27.1%)。19条患肢踝肱指数(ankle/brachial index,ABI)为0,22条患肢在0.1～0.5之间,7条患肢在0.51～0.6之间。结果技术成功率为93.8%。术后33条患肢疼痛缓解(73.3%),其中27条患肢无疼痛(64.3%)。10条患肢症状减轻(22.2%),其中3条复发。足部溃疡的9条患肢中,1条患肢足部小溃疡愈合。13条足趾或足部组织坏疽的患肢,2条行膝下截肢,2条行半足截除。24条患肢术后ABI增加0.5以上,12条增加0.31～0.5,7条增加0.1～0.3。42条患肢被随访,随访率为93.3%;时间平均为8.5个月(1～18个月)。本组共截肢5条患肢,总救肢率为88.1%。结论膝下小动脉腔内成形术在无法接受动脉旁路移植的严重下肢缺血的患者可以作为首选治疗方法。     

膝下血管微球囊扩张成形术在糖尿病足治疗中的应用

目的探讨膝下血管微球囊扩张成形术在糖尿病足治疗中的应用价值。方法选择我院2005年10月-2006年9月收治的以膝下动脉闭塞为主的糖尿病足患者33例，共44条肢体，均采用单纯球囊扩张成形术治疗膝下血管病变。结果44条肢体中技术成功40条（90．91％），临床成功42条（95．45％）。术后平均随访6个月（2～12个月），所有患者的肢体症状均未见加重或复发。结论膝下血管微球囊扩张成形术可以有效改善肢体远端血供，有效防止糖尿病足病发展，促进肢端创面愈合，提高患者生活质量，近期疗效显著，远期疗效尚待进一步观察。     

膝下动脉球囊血管成形术治疗重症下肢缺血的临床研究

目的 评价膝下动脉闭塞首选球囊血管成形术的临床治疗效果.方法 2005年12月至2009年5月,对于连续收治且符合手术指征的54例(61条肢体)膝下动脉重度狭窄或闭塞的重症下肢缺血患者,采用膝下动脉球囊血管成形术进行治疗.其中男性37例,女性17例,平均年龄66岁.术前踝肱指数平均0.43±0.27.根据病变部位选择手术方法,膝下动脉病变首选球囊血管成形术,合并髂股动脉病变同时进行血管重建(支架置入或动脉旁路术).结果 髂股动脉重建(28条肢体行支架置入,5条肢体行动脉旁路术)均一期成功.膝下动脉球囊血管成形术57条肢体获得一期成功,技术成功率93.4%.围手术期主要并发症为小腿血肿3例(4.9%),膝下截肢2例(3.3%).术后踝肱指数增加至0.86±0.21,与术前相比差异有统计学意义(P<0.01).本组平均随访时间(16±11)个月,一期通畅率61.1%,21条肢体发生再狭窄(38.9%),其中10条肢体再次接受外科干预,二期通畅率75.9%.截肢3条肢体,总的救肢率91.8%.结论 球囊血管成形术是治疗重症下肢缺血安全有效的方法,可以作为膝下动脉病变首选的外科干预手段.     

经皮腔内血管成形术治疗膝下动脉粥样硬化闭塞症的评价

目的 评价经皮腔内血管成形术(percutaneous transluminal angioplasty,PTA)治疗膝下动脉粥样硬化闭塞症(arteriosclerosis obliterans,ASO)的疗效.方法 回顾性研究2007年1月至2011年6月我科收治的累及膝下动脉ASO并行PTA治疗的患者的临床资料.结果 138例患者,平均年龄(77.31±7.52)岁,治疗膝下动脉所用球囊平均直径 2.8mm(2～4mm),平均长度110.6mm(40～170mm),术中及术后无严重并发症.术后早期治疗肢体临床症状明显改善率为100%,无截肢患者.平均随访24.1个月(4～58个月),治疗肢体术后2年临床症状明显改善率78.4%,救肢率93.9%.结论 PTA治疗膝下动脉ASO可有效改善临床缺血症状并提高救肢率.     

下肢动脉硬化闭塞症腔内治疗后支架内再狭窄的治疗

目的:探讨下肢动脉硬化闭塞症(ASO)腔内治疗后支架内再狭窄的治疗体会。方法:回顾性分析2012年6月至2014年12月收治的支架内再狭窄的31例下肢ASO患者(49条肢体)资料,其中狭窄病变37条肢体,闭塞病变12条肢体;病变长度8.5~35 cm,平均(25.2±7.5)cm。结果:所有患者均接受腔内治疗,包括单纯球囊扩张成形术35例,球囊扩张后导管溶栓术3例,球囊扩张后支架植入术3例,导管溶栓后球囊扩张术7例,斑块旋切术1例。术后所有患者症状均不同程度缓解,平均踝肱指数较术前明显升高(P0.05)。28例获得随访3~32个月,平均(16.2±5.8)个月,期间出现再狭窄6例(21.4%),均再次行球囊扩张成形术,无截肢及死亡病例。结论:结合其他腔内疗法,球囊扩张术治疗下肢动脉支架内再狭窄疗效满意。     

腔内血管成形术治疗膝下动脉缺血性疾病

腔内血管成形术适用于膝下动脉缺血性疾病的治疗。本文阐释腔内血管成形术术后再狭窄的发生及其临床意义,评价腔内血管成形术治疗膝下动脉缺血性疾病的安全性及有效性。     

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.     

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.     

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.     

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.