后路显微内窥镜治疗腰椎间盘突出症

目的 探讨后路显微内窥镜系统治疗腰椎间盘突出症的疗效。方法 总结自2002年10月以来，采用MED治疗腰椎间盘突出症58例，其中合并神经根管狭窄18例，评价其疗效。结果 24例患者术后次日原有腰腿痛症状消失．21例明显减轻。术后4～13个月的随访，根据疗效评定标准：优31例，良26例．进步1例。结论 MED治疗腰椎间盘突出症具有手术视野清晰．操作更为安全．攒伤小，不影响脊柱的稳定性，具有减压彻底．疗效显著等优点，同样适用合并神经根管狭窄。     

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。     

显微椎间盘镜手术系统治疗腰椎间盘突出并侧隐窝狭窄症

目的：介绍显微椎间盘镜手术系统(MED)治疗腰椎间盘突出并侧隐窝狭窄症。方法：自2000年10月～2002年12月用MED治疗腰椎间盘突出症108例，其中46例合并有侧隐窝狭窄。结果：随访6～24个月，按Na—Kai疗效评定，34例，良8例，可3例，差1例。优良率为91．3％。结论：应用MED治疗腰椎间盘突出并侧隐窝狭窄症，只要遵循神经根彻底减压的原则，就可取得好的疗效。     

显微内窥镜手术治疗腰椎间盘突出症

目的 探讨显微内窥镜椎间盘切除系统(MED)治疗腰椎间盘突出症的特点及应用中出现的情况和并发症，以提高手术疗效。方法 通道管经棘突旁小切口进入，在电视监视下显露椎板间隙，咬除少量椎板下缘及黄韧带，扩大椎间隙，显露硬脊膜、神经根以及突出椎间盘的髓核组织并予以摘除；根据神经根是否松弛，作侧隐窝、神经根管扩大。结果 本组87例，术后随访20-31个月，平均26．4个月。手术时间40～160min，平均67min。术中出血30～500ml，平均95．2ml。术后平均2-3d下床，16d恢复日常生活，29d恢复工作。按Nakai标准评定，优良率93．1％：术中可能出现(1)定位错误；(2)进入椎管困难；(3)止血困难；(4)硬脊膜损伤；(5)髓核残留。结论 MED具有创伤小、出血少、恢复快，能直接摘除突出的髓核组织、扩大狭窄的侧隐窝及神经根管对神经根的压迫，最大限度的保持了脊柱后路的稳定性，本术式适用于大多数腰椎间盘突出症或合并侧隐窝狭窄和／或神经根管狭窄症的患者。     

显微内窥镜腰椎间盘切除系统治疗腰椎间盘突出症

目的分析显微内窥镜腰椎间盘切除系统(MED)治疗腰椎间盘突出症的技术特点和疗效。方法54例腰椎间盘突出症行MED治疗,手术采用后路椎间盘镜手术进行“开窗”减压,髓核摘除术及神经根减压。结果随访6~12个月,按照Macnab标准:优40例,良6例,可4例,优良率92.6%。结论该方法适用于腰椎间盘突出症或伴轻度侧隐窝、神经根管狭窄的患者,近期疗效好且具有创伤小、出血少、术后恢复快等优点。     

显微椎间盘镜治疗合并神经根管狭窄的腰椎间盘突出症

目的分析内镜下后路椎间盘髓核摘除，神经根减压、松解术冶疗合并腰椎管狭窄的椎间盘突出症的临床疗效。方法对合并侧隐窝及神经根管狭窄的腰椎间盘突出症58例，采用后路显微内镜（MED）下髓核摘除、神经根管扩大术治疗。结果术后58例症状均明显改善，未出现损伤椎体前方大血管、神经症状加重、脑脊液外漏和感染等近期并发症和复发、腰椎失稳等远期并发症。结论内镜下后路髓核摘除术是外科治疗椎间盘突出症的一种优良方法，对合并神经根管狭窄病例，正确把握手术适应证，发挥微创技术的优越性，同样可以取得满意疗效。     

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。     

显微内窥镜治疗合并腰椎管狭窄症的椎间盘突出症

目的 探讨后路显微内窥镜经椎板间隙入路行椎间盘摘除术及神经根管扩大术治疗腰椎间盘突出症合并腰椎管狭窄的技术特点和效果分析.方法 对68例腰椎间盘突出症合并腰椎管狭窄应用后路显微内窥镜系统行髓核摘除及神经根管减压手术治疗.结果 60例随访3～48个月,按Nakai标准评定:优43例,良13例,可3例,差1例,优良率93....     

显微内窥镜下治疗腰椎间盘突出伴椎管狭窄

目的 研究后路显微内窥镜(MED)治疗腰椎间盘突出合并椎管狭窄的临床应用价值。方法 显微内窥镜下髓核摘除，同时扩大侧隐窝，部分病人需要同时扩大神经根管，对受压神经根充分减压。结果 本组经后路显微内窥镜下治疗腰椎间盘突合并椎管狭窄452例，术后随访305例，优263例，良31例，差11例，优良率达96．3％。结论 MED在神经根充分减压的基础上，具有损伤小，恢复快，脊柱稳定性好，适用于单侧1个间隙或同侧2个间隙椎间盘突出合并椎管狭窄的治疗。     

显微内窥镜下治疗腰椎间盘突出伴椎管狭窄

目的研究后路显微内窥镜(MED)治疗腰椎间盘突出合并椎管狭窄的临床应用价值。方法显微内窥镜下髓核摘除,同时扩大侧隐窝,部分患者需要同时扩大神经根管,对受压神经根充分减压。结果本组经后路显微内窥镜下治疗腰椎间盘突出合并椎管狭窄452例,术后随访305例,优263例,良31例。差11例,优良率达96.3％。结论MED在神经根充分减压的基础上,具有损伤小,恢复快,脊柱稳定性好,适用于治疗单侧1个间隙或同侧2个间隙椎间盘突出合并椎管狭窄。     

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.