老年腰椎管狭窄症的手术治疗策略

目的分析老年腰椎管狭窄症的特点,探讨老年腰椎管狭窄症的手术治疗策略,提高手术疗效。方法 2003-02-2009-02,对67例65岁以上的老年性腰椎管狭窄症患者,针对引起狭窄和症状的不同因素,分别采取椎板开窗、全椎板切除椎管减压、全椎板切除椎管减压并植骨融合等手术方式,并注重围手术期治疗,参照中华骨科学会脊柱学组腰背痛手术标准进行疗效评定。结果67例患者均顺利完成手术和度过围手术期,术后随访64例,平均18月。治疗效果优良率90.63%。结论年腰椎管狭窄症具有其本身的特点,应针对不同的病变情况,采用个体化手术治疗措施,注重椎管有效减压和脊柱稳定性的平衡,并重视围手术期治疗,可取得满意手术效果。     

高龄退变性腰椎管狭窄症的临床特点及手术治疗

目的 探讨高龄退变性腰椎管狭窄症患者的临床特点和疗效.方法 对272例高龄退变性腰椎管狭窄症行手术治疗,椎板问开窗减压55例(A组),全椎板或半椎板切除减压69例(B组),全椎板切除减压结合椎弓根螺钉内固定结合横突间自体植骨148例(C组).结果 244例获得随访似6～45个月,平均25.8个月,A、B、C组优良率分别为78.8%、75.9%、81.3%.结论 高龄退变性腰椎管狭窄症具有特殊的临床特点,手术风险高,应合理选择手术方法,可减少并发症.     

两种手术方法治疗腰椎管狭窄症182例的临床研究

目的：通过精确责任神经根定位微创开窗减压和全椎板切除椎管减压椎弓根钉内固定术治疗腰椎管狭窄症的临床疗效,讨论两种方法的优缺点及适应证。方法：2007年3月～2013年3月收治的腰椎管狭窄症患者182例,男97例,女85例;年龄46～82岁,平均58．6岁。所有患者均行腰椎正侧、双斜、过伸、过屈位片及CT、MRI检查。中央管狭窄17例,侧隐窝狭窄95例,混合性狭窄70例,合并腰椎假性滑脱或不稳定者56例。患者分为：微创开窗减压治疗组88例,全椎板切除椎管减压椎弓根钉内固定术治疗组94例。结果：按NAKAI疗效评定标准,优良率：微创开窗减压组90．9％（80／88）,全椎板切除椎弓根钉内固定术治疗组92．6％（87／94）,两组优良率差异无显著性。微创开窗减压治疗组,手术时间、术中失血量、镇痛药使用、术后下床活动时间、住院时间均少于全椎板切除椎管减压椎弓根钉内固定术治疗组（P〈0．01）,两组间脑脊液漏的发生率和术后疗效优良率差异无显著性（P〉0．05）。腰椎失败综合证3例发生于全椎板切除椎弓根钉内固定术治疗组。结论：微创开窗减压与全椎板切除椎管减压椎弓根钉内固定术治疗腰椎管狭窄症疗效无明显差异,微创开窗减压治疗腰椎管狭窄症创伤小,术后恢复快,疗效确切。全椎板切除椎管减压椎弓根钉内固定术应用于合并腰椎假性滑脱或不稳定患者更为合理。     

小切口椎板有限切除和椎管扩大治疗腰椎管狭窄症

目的探讨小切口椎板有限切除和椎管扩大治疗腰椎管狭窄症的疗效。方法本组36例患者根据腰椎管狭窄症的病变特点,施行病变节段有限手术。结果患者均获随访,时间7个月～5年,优良率91．7％。缩论采用小切口椎板有限切除和椎管扩大治疗腰椎管狭窄症,损伤小,即可获得减压作用又能保持脊柱的稳定性,临床疗效满意。     

腰椎管狭窄症患者行椎管成形术中保留腰椎后柱结构对疗效的影响

正随着老年人口的增长,腰椎管狭窄症发生率呈逐年增长的趋势[1]。全椎板切除减压术是该病的主要治疗方案,但是由于切除了腰椎后柱结构,容易引发脊柱不稳、瘢痕填充椎管压迫神经、腰背痛等并发症[2]。因此,本文主要针对腰椎管狭窄症患者行椎管成形术中保留腰椎后柱结构对临床疗效的影响展开分析,报道如下。1资料与方法1.1临床资料选取2010-01-2014-12收治的100例腰椎管狭窄症患者作为观察对     

椎板间隙入路椎间盘镜治疗腰椎管狭窄症

目的：探讨在椎板间隙入路椎间盘镜下有限化手术治疗退行性腰椎管狭窄症。方法：选取退行性腰椎管狭窄症病例，在椎板间隙入路椎间盘镜下行椎管有限减压。咬除病变间隙上位椎板下缘、肥厚的黄韧带和下位椎板上缘，摘除突出椎间盘髓核，松解神经根粘连，侧隐窝减压，必要时切除部分关节突。结果：应用椎板间隙入路椎间盘镜治疗迟行性腰椎管狭窄症，行椎管有限减压87例，减压彻底。82例得到随访，优良串92．7％，手术效果满意。结论：单纯腰椎间盘膨出或突出、黄韧带肥厚和小关节增生引起的退行性腰椎管狭窄症是椎板间隙入路椎间盘镜下椎管有限减压的适应证。满意的手术效果取决于：病人选择适当，术中操作精细，减压彻底。     

全椎板切除术治疗腰椎管狭窄症

目的 了解全椎板切除术治疗腰椎管狭窄症的远期效果。方法 对156例腰椎管狭窄症施行全椎板切除,突出髓核除,神经根管扩大,椎管减压。结果 对资料完整89例获得2～6年随访分析,平均随访3年8个月,优良78例,可8例,差3例。结论 全椎板切除术治疗腰椎管狭窄症3年疗效最佳,优良率87．6％。     

影响腰椎管狭窄症术后效果和椎间不稳定性的因素

腰椎管狭窄症手术治疗分为全 (半 )椎板扩大切除和椎板开窗减压术 2种。 1981年以前作者主要采用全椎板扩大切除术 ,1985年以后采用开窗减压术。但是这些手术均不能预防术后椎管再度狭窄的发生。特别是随着患者年龄的增长 ,骨性退变的加重 ,可引起椎管再度狭窄。引发骨性退变的     

有限椎板切除减压治疗退行性腰椎管狭窄症

退行性腰椎管狭窄症(LSS)的治疗一般采用传统的全椎板切除减压，切除范围较大，包括棘突、双侧椎板及部分关节突等，术后易引起脊柱不稳、硬膜外广泛瘢痕粘连继发医源性椎管狭窄等腰椎术后失败综合征。自1995年9月～2001年3月应用有限的椎板切除(保留棘突、棘上韧带、棘间韧带)椎管减压治疗退行性腰椎管狭窄症61例，其中9例同时行后路内固定植骨融合术，取得了满意效果。     

椎间融合器联合椎弓根钉系统内固定治疗腰椎间盘突出伴椎管狭窄症

目的 探讨椎间融合器联合椎弓根钉系统内固定治疗腰椎间盘突出伴椎管狭窄症的疗效.方法 在2005-01-2009-02期间对18例腰椎间盘突出伴椎管狭窄症的患者采用了经椎弓根固定,全椎板切除椎管减压、单枚或双枚椎间融合器植入融合术(内固定组).并随机抽取18例同期单纯椎板切除椎管减压及髓核摘除的此类患者作为对照组(非内固...     

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.