腰椎间盘突出症MED手术体会

目的：探讨显微内窥镜椎间盘切除术(MED)治疗腰椎间盘突出症的适应证选择及其相关问题。方法：选择单间隙或同侧双间隙腰椎间盘突出症38例，应用MED手术系统进行治疗。结果：38例中应用MED手术系统完成单间隙手术34例，完成同侧双间隙手术2例，硬膜及神经根与周围组织粘连较重难以分离改开放手术2例。36例MED平均手术时间65min，术中出血平均90ml，切口均一期愈合，无1例感染及椎间盘炎，平均住院12d，平均随访4个月，近期疗效按Macnnab标准，优22例，良11例，可3例，优良率91．67％。结论：应用MED手术系统治疗腰椎间盘突出症，既能通过内镜直观准确地摘除突出的椎间盘、解除神经根压迫，又能最大限度地减轻对腰椎稳定性的影响，只要适应证选择得当、注意腹部悬空、术中止血及神经根保护，近期疗效明显优于传统的开放手术。     

MED治疗腰椎间盘突出症时对神经根变异的探查

目的：观察显微内窥镜下椎间盘切除术（microendoscopic discectomy，MED）治疗腰椎间盘突出症时神经根变异情况，防止出现术中神经根损伤。方法：回顾分析自1999年10月至2003年12月应用MED治疗的腰椎间盘突出症患者724例，其中男452例，女272例。对术中发现存在腰骶神经根变异患者的临床特点及术中所见进行统计分析。结果：724例腰椎间盘突出症患者有37例神经根变异，发生率为5.1％。与术前的临床表现吻合，全部神经根变异患者均在MED下完成手术，无一例出现神经根损伤。结论：仔细探查及分离突出髓核周围神经根发出情况．确定有无神经根变异是防止MED治疗腰椎间盘突出症时发生神经根损伤的重要环节之一。     

腰椎间盘突出症传统手术方式与内窥镜(MED)疗效的回顾性分析

目的探讨传统开放的椎板间隙"开窗"手术方式(A组)和MED(B组)治疗腰椎间盘突出症的临床效果及相关问题。方法根据临床表现结合影像学检查结果确定手术方式,625例施行开放手术,其中单间隙开窗482例、单侧双间隙开窗65例、双侧开窗78例;546例施行MED。根据Nakai标准评价疗效,并对手术时间、出血量、并发症、术后恢复时间进行比较分析。结果开放手术组优良率为94.2%,MED手术组优良率为98.3%,差别无统计学意义(P0.05),两组手术时间、并发症无显著性差异,出血量、术后恢复时间有统计学意义。结论两种手术方式疗效相近,传统开放手术仍然是治疗腰椎间盘突出症的主要手段,MED作为现代微创技术,具有手术创伤小、恢复快的优点,但手术并不简便,且技术要求更高,只要具备熟练的开放手术技术,在严格选择适应证的前提下才能获得优良效果。     

腰椎间盘突出症MED手术体会

目的:探讨显微内窥镜椎间盘切除术(MED)治疗腰椎间盘突出症的适应证选择及其相关问题.方法:选择单间隙或同侧双间隙腰椎间盘突出症38例,应用MED手术系统进行治疗.结果:38例中应用MED手术系统完成单间隙手术34例,完成同侧双间隙手术2例,硬膜及神经根与周围组织粘连较重难以分离改开放手术2例.36例MED平均手术时间65min,术中出血平均90ml,切口均一期愈合,无1例感染及椎间盘炎,平均住院12d,平均随访4个月,近期疗效按Macnnab标准,优22例,良11例,可3例,优良率91.67%.结论:应用MED手术系统治疗腰椎间盘突出症,既能通过内镜直观准确地摘除突出的椎间盘、解除神经根压迫,又能最大限度地减轻对腰椎稳定性的影响,只要适应证选择得当、注意腹部悬空、术中止血及神经根保护,近期疗效明显优于传统的开放手术.     

经后路椎管内椎间盘镜治疗钙化型腰椎间盘突出症

目的：介绍经后路椎管内显微内窥镜椎间盘切除手术系统（MED）治疗钙化型腰椎间盘突出症。方法：1999年6月－8月用MED治疗钙化型腰椎间盘突出症21例。详细介绍了手术过程、操作技巧及手术适应证。结果：全部患者术后无并发症。平均随访16．1个月,按Nakal疗效评定分级属优14例、良4例、可3例,优良率为85．7％。结论：严格掌握适应证、娴熟操作技巧是钙化型腰椎间盘突出症行MED治疗成功的关键。     

后路显微椎间盘镜治疗腰椎间盘突出症围手术期并发症的防治

目的：探讨后路显微椎间盘镜（MED）治疗腰椎间盘突出症的围手术期并发症的原因和防治措施。方法：回顾性分析215例MED治疗腰椎间盘突出症的围手术期并发症发生及治疗情况。结果：发生围手术期并发症19例。发生率为8.84%。其中术中椎管内血管破裂出血6例，单纯硬脊膜破裂4例。硬脊膜破裂合并神经根束损伤1例，合并马尾神经束损伤1例，神经根牵拉伤1例，突出椎间盘摘除和/或侧隐窝扩展不足3例。原节段对侧突出遗漏1例。遗漏另一节段突出2例。全组无术后椎间隙感染及死亡。结论：术者经验和适应证的选择与MED围手术期并发症有关；强调循序渐进的原则可降低并发症的发生率。     

后路显微内窥镜下手术治疗腰椎间盘突出症的疗效分析

目的探讨后路显微内窥镜下手术治疗腰椎间盘突出症的适应证与疗效分析。方法对120例采用后路显微内窥镜下手术治疗腰椎间盘突出症进行分析。结果120例中3例改为开放手术,117例完成内窥镜下手术,术中出现硬脊膜撕裂伤4例、神经根牵拉伤2例,按Nakai评价标准本组优良率达94％。结论后路显微内窥镜下手术治疗腰椎间盘突出症是一种疗效满意的微创手术。但须根据手术适应证与术者经验选择合适患者,才能提高该手术治疗效果与降低并发症。     

后中路椎间盘镜手术的适应证

目的：探讨后中路椎间盘镜手术系统（MicroEndosoopic Discectomy,MED)治疗腰椎间盘突出症的适应证。方法：215例腰椎间盘突出症中，按椎间盘突出的类型选择149例行MED手术，66例腰椎间盘突出症行开放式手术。结果：本组215例。随访6-16个月，按Nakai分级；MED组，优112例，良27例，可10例，优良率93.28%；开放式手术组，优48例，良11例，可7例，优良率89.39%。结论：MED微创手术具有创伤小，疗效好，恢复快等优点，但手术适应证有一定局限性，MED主要适用于单节段外侧型的腰椎间盘突出症，也适用于部分伴钙化或侧隐窝狭窄的腰椎间盘突出症，不适用于伴腰椎不稳或中央型腰椎管狭窄的腰椎间盘突出症，应抿弃盲目扩大MED适应证，镜下操作失败再中途转行开放式手术的错误做法。     

后路显微内窥镜治疗腰椎间盘突出症合并神经根管狭窄

目前显微内窥镜(microendoscop，MED)治疗腰椎间盘突出症的文献报告较多，其优越性也被越来越多的骨科医生所认同，随着临床实践的不断深入及手术操作日趋完善熟练，其适应证也逐渐扩大。亦有MED治疗神经根管狭窄症的报告，但对腰椎间盘突出症合并神经根管狭窄的专门报告较少。自2002年10月以来采用MED治疗28例腰椎间盘突出症合并神经根管狭窄，取得理想的疗效。     

腰椎间盘镜下治疗腰椎间盘突出症

目的　分析腰椎间盘镜 (MED)监视下手术治疗腰椎间盘突出症效果和影响因素。方法　MED手术切除腰椎间盘突出症 90例 ,有神经根管狭窄者同时行神经根管扩大术。结果　所有病例获得随访 ,平均 6个月。据改良Macnab评分法 ,优良率 95 5 6 %。结论　借助腰椎间盘镜及显微手术器械手术具有创伤小、恢复快、出血少、痛苦轻、疗效好等优点 ;但术者须熟练操作 ,适应证选择应得当。     

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.     

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.     

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.     

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.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.