后路椎间盘镜在治疗腰椎管狭窄症中的应用

目的：探讨后路椎间盘镜在治疗腰椎管狭窄症中的应用。方法：2000年2月--2001年12月退行性腰椎管狭窄症142例行后路椎间盘镜下椎管有限减压、全椎板或半椎板切除减压、开窗减压术。结果：应用后路椎间盘镜行椎管有限减压87例，减压松解充分。82例随访平均18月，优良率92．7％(优58例，良18例)。无并发症。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后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。     

后路椎间盘镜显微治疗腰椎椎管狭窄症

目的 报道显微后路椎间盘镜治疗退行性腰椎椎管狭窄症的临床效果。方法 选取退行性腰椎管狭窄症病例，椎板间隙入路椎间盘镜下行椎管减压，单侧单节段开窗减压23例，双侧单节段开窗减压12例，单侧双节段开窗减压9例，单侧双节段半椎板切除减压4例。结果 除1例术中硬膜破裂改常规手术外，其余病例均在手术显微镜下完成腰椎管减压术。所有病例获得5～18个月随访，平均8．3个月，优良率92％。结论 显微后路椎间盘镜治疗退行性腰椎管狭窄症具有手术创伤小、神经根减压彻底、术后恢复快的特点；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其适应证。     

腰椎间盘突出症合并椎管狭窄23 例治疗分析

目的探讨经后路椎间盘镜手术治疗合并腰椎管狭窄症的椎间盘突出症的临床应用。方法采用后路椎间盘镜进行单侧开窗减压术。通过术前标记腰椎正侧位片定位，于定位棘突间隙后正中偏患侧作长约1.5 cm小切口，逐级扩张后置入工作通道管，钻除部分椎板，置入内窥镜，于电视监视器下显露椎板、增生内聚的关节突、肥厚的黄韧带及突出的椎间盘髓核组织，彻底解除其对硬脊膜、神经根的压迫。结果本组共治疗合并腰椎管狭窄症的腰椎间盘突出症23例，平均随访7个月，按Prolo标准评定，治愈20例，有效2例，无效1例。结论本术式在严格掌握适应证前提下对合并腰椎管狭窄症的腰椎间盘突出症患者效果明显。     

椎间盘镜治疗合并腰椎管狭窄症的椎间盘突出症23例分析

目的 探讨经后路椎间盘镜手术治疗合并腰椎管狭窄症的椎间盘突出症的临床应用。方法 采用后路椎间盘镜进行单侧开窗减压术。通过“C”形臂X线机或摄侧位X线片定位，于后正中作长约1.5cm小切口，逐级扩张后置入工作通道管，钻除部分椎板，置入内镜，于电视监视器下显露椎板，增生内聚的关节突、肥厚的黄韧带及突出的椎间盘髓核组织，彻底解除其对硬脊膜、神经根的压迫。结果 本组共治疗合并腰椎管狭窄症的腰椎间盘突出症23例，平均随访7个月，按Prolo标准评定，治愈20例，有效2例，无效1例。结论 本术式在严格掌握适应证前提下对合并腰椎管狭窄症的腰椎间盘突出症的患者效果明显。     

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。     

可动式椎间盘镜下单侧开窗双侧减压治疗腰椎管狭窄症

目的 探讨可动式椎间盘镜下单侧开窗双侧减压治疗腰椎管狭窄症的疗效.方法 2007年6月至2009年6月采用可动式椎间盘镜下单侧开窗双侧减压治疗退行性腰椎管狭窄症32例,男14例,女18例;年龄56～74岁,平均65岁.均为双侧椎管狭窄合并椎问盘突出,有间歇性跛行和坐骨神经痛等症状,双下肢症状以一侧为重.在症状严重侧行棘突旁2 cm纵切口,在可动式椎间盘镜下行单侧椎板间隙开窗,神经根通道减压、突出髓核摘除;在棘突和椎板腹侧分别向上、下方用棉片压低保护硬膜囊,潜行咬除棘突基底部,在棘突基底、椎板腹侧与硬膜囊背侧之间形成工作空间,经此空间潜行咬除对侧椎板下缘和增厚的黄韧带,直至显露松解对侧神经根起始部.结果 术中无神经损伤发生,无中途转开放手术病例.发生硬膜囊撕裂2例,用棉片将其压低后完成手术.手术时间5～100min,平均70min;术中出血量50～350ml,平均150ml.术后CT示减压充分,中央椎管和对侧椎管扩大,对侧椎板、关节突和椎旁肌等结构保留完好.全部病例随访6～24个月,平均12个月.根据Macnab标准,优21例,良11例.结论 可动式椎间盘镜下单侧开窗双侧减压治疗腰椎管狭窄症操作简便,能保留对侧结构,达到双侧减压目的 ,早期随访结果优良.对双侧严重骨性狭窄者应慎用.     

腰椎管狭窄症的治疗(综述)

腰椎管狭窄症的发生,是由于腰椎管、神经根管或椎间孔这些管腔的一个或全部发生狭窄时,压迫椎管内的马尾或脊神经根而造成的。造成狭窄的原因,常由于骨质或软组织的变化,如椎管中心型狭窄,主要由于椎板肥厚、黄韧带肥厚或伴有椎间盘突出,或由于小关节骨关节炎,增生的关节突向椎管内挤压。而周缘型狭窄(指在神经根管内或椎间孔发生的     

显微内窥镜下手术治疗退行性腰椎管狭窄症

目的探讨显微内窥镜下手术治疗退行性腰椎管狭窄症的方法、疗效及并发症。方法显微内窥镜下手术治疗132例退行性腰椎管狭窄症,经椎板间隙切除黄韧带、部分椎板和关节突,充分减压硬膜囊和神经根。结果平均手术时间46min,平均术中出血量75ml,全部病例镜下完成手术,出现并发症7例,占5.3%,其中硬脊膜损伤5例,硬膜外血肿1例,椎间盘炎1例。平均随访13.5个月,疗效参考Nakai标准,优97例(73.5%),良23例(17.4%),可7(例5.3%),差5例(3.8%)。结论显微内窥镜下手术治疗退行性腰椎管狭窄症能够充分减压,并能维持腰椎稳定,术后效果优良。     

退变性腰椎管狭窄症影像学表现与非手术治疗研究概况

腰椎管狭窄症是导致腰腿痛的常见病，发病率仅次于腰椎间盘突出症，占椎管疾病的第2位。临床上按病因一般分为发育性腰椎管狭窄症（lumbar spinal stenosis，LSS）及退变性腰椎管狭窄症（degenerative lumbar spinal stenosis，DISS）两类，LSS以先天椎板肥厚、椎弓根短缩及骨性中央管狭窄为特点，诊断较易明确，一般采用手术治疗。DLSS多因组成腰椎管相应结构发生退变，椎间盘膨出或突出、关节突增生内聚以及黄韧带肥厚等导致腰椎管、神经根管、     

老年骨质疏松引起椎管狭窄症的原因及治疗方法（附61例报告）

因老年骨质疏松椎间盘髓核中蛋白粘多糖及水份的减少、纤维环松弛、椎间隙变窄、椎间盘膨出，加上黄韧带肥厚皱折，后纵韧带钙化增生，使椎管容积缩小是造成颈、腰椎管狭窄的主要原因。８年来收治颈、腰椎管狭窄症６１例，最大年龄７６岁，最小年龄５８岁，对颈狭窄症采用颈后路单开门椎管扩大成形术，本法优点既保护大部椎板起保护脊髓的作用，又起到椎管扩大充分减压的作用，对有要椎管狭窄症采用保留关节突，棘突完整取下，将椎管     

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.     

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.     

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.