椎弓根钉棒系统治疗严重胸腰椎骨折脱位

目的 观察后路椎弓根钉棒系统治疗严重胸腰椎骨折脱位的疗效.方法 经后路椎弓根钉棒系统内固定减压、植骨治疗21例严重胸腰椎骨折脱位.结果 21例随访6个月～2年,全部病例基本恢复了正常椎体序列、Cobb角及椎体高度.结论 椎弓根钉棒系统复位固定结合后路植骨融合,是治疗严重胸腰椎骨折脱位的有效方法.     

CD、AF椎弓根内固定治疗胸腰段椎体不稳定骨折

目的 评价CD、AF椎弓根内固定系统治疗胸腰段椎体不稳定骨折疗效。方法 采用CD（33例）、AF（32例）椎弓根内固定治疗胸腰段椎体不稳定骨折。必要时切除椎板减压,直视下嵌击性复位。行横突间植骨融合。结果 65例获3-29个月随访,行X线及CT复查,骨折脱位复位率达95％。CD组中有2例断钉,3例钉棒松动,椎体复位高度丢失4～6mm。AF组无1例断钉及钉棒松动。结论 CD、AF椎弓根内固定系统治疗胸腰段椎体不稳定骨折,固定牢靠,椎体高度再丢失少。AF较CD操作更加简单、可靠。     

AF椎弓根钉系统治疗胸腰椎爆裂性骨折46例

目的探讨AF椎弓根钉内固定系统治疗胸腰椎爆裂性骨折的疗效。方法应用AF经椎弓根钉内固定系统治疗胸腰椎爆裂性骨折46例。结果平均随访11个月。46例椎体前缘高度由术前平均25％恢复至平均95％。椎管内移位骨块复位率达90％。神经损伤的恢复按ASIA分级：A级中19例无变化，余27例均提高1～2级。结论AF椎弓根钉内固定系统能达到满意复位固定及椎管有效减压，是一种治疗胸腰椎爆裂性骨折理想的方法。     

AF系统胸腰椎爆裂骨折初步观察及体会

[目的]观察AF椎弓根钉内固定系统治疗胸腰椎爆裂骨折的疗效。[方法]应用AF椎弓根钉内固定系统治疗胸腰椎爆裂骨折17例。[结果]随访8个月-3年，平均随访12个月。17例椎体前缘高度由术前平均30％恢复至平均95％，椎管内移位骨块复位率达90％，神经损伤的恢复按ASIA分级：A级中1例无变化，余16例均提高1-2级。[结论]AF椎弓根钉内固定系统能达到满意复位固定及椎管有效减压，是一种治疗胸腰椎爆裂骨折理想的方法。     

中国骨与关节损伤杂志2007年（第22卷）分类目录

脊柱前路带锁钢板治疗多节段颈椎骨析1:38经椎弓根植骨结合GSS-Ⅱ型内固定治疗胸腰椎爆裂性骨折1:39AF椎弓根钉系统治疗胸腰椎爆裂性骨折46例1:41胸腰段经椎弓根脊柱固定置钉的X-CT个性化方案1:42GSSⅢ代后路复位固定椎体间融合治疗Ⅰ、Ⅱ度腰椎滑脱1:44下颈椎骨折脱位治疗方法     

胸腰椎爆裂骨折的外科治疗分析

目的探讨胸腰椎爆裂骨折的最佳治疗方法。方法根据骨折类型不同,采用不同方法治疗胸腰椎爆裂性骨折89例,其中AF系统椎弓根钉内固定68例,Dick固定6例,ALPS固定8例,Luque棒固定2例,中华长城5例,并行植骨49例。结果随访9个月～3年6个月,平均2年。术后内固定稳固,骨折复位佳,椎管有效径恢复,术后神经功能较术前均有恢复。结论胸腰椎爆裂骨折,如骨折块占椎管容积>30%以上,椎管矢径小于10mm及伴有脊髓损伤者应积极进行手术椎管减压复位固定,矫正后倾角,同时术中脊髓造影、C臂机监视复位应达到以下标准:压缩椎体扩张80%以上;后弓角<10°,恢复椎管容积及脊髓减压,椎体间脱位完全复位。     

后路椎弓根器械治疗胸腰椎骨折脱位

目的研究短节段椎弓根器械复位固定治疗胸腰椎骨折脱位的方法和疗效。方法应用短节段椎弓根器械复位固定治疗胸腰椎骨折脱位66例,41例行横突间或椎板间植骨融合,9例经伤椎椎弓根行可吸收球囊椎体成形术,平均随访14个月。结果短节段椎弓根器械(Dick除外)复位固定治疗胸腰椎骨折脱位,伤椎术后椎体高度比和Cobbs角有显著改善,41例后路植骨融合和9例椎体成形术患者无断钉、钉松动或矫正度丢失现象。结论短节段椎弓根器械复位固定,结合后路植骨融合或椎体成形术是治疗胸腰椎骨折脱位的良好方法。     

经椎弓根固定治疗胸腰椎不稳定骨折

目的　探讨后路椎弓根螺钉内固定治疗胸腰椎不稳定骨折的临床效果。方法　应用经椎弓根螺钉内固定系统治疗胸腰椎骨折脱位 5 6例 ,其中Steffee 8例 ,RF 11例 ,AF 2 1例 ,Tenor 12例 ,USS 4例 ,分别进行后路减压、植骨融合 ,比较其神经功能恢复及骨折愈合情况。结果　 4 2例获得随访 ,时间 5～ 2 4个月。神经功能按Frankel分级 :除 5例A级无恢复外 ,其他级别有 1～ 4级的恢复。 5例骨折复位不满意或内固定失败 ,其余骨折均顺利愈合 ,椎体高度无再丢失。结论　椎弓根螺钉可行短节段脊柱内固定 ,重建脊柱稳定性 ,脊柱融合率高 ,临床效果满意     

AF椎弓根螺钉系统治疗胸腰椎骨折

目的：回顾性分析AF（atlas fixator)椎弓根螺钉内固定系统治疗胸腰椎骨折脱位脊髓损伤的效果。方法：采用AF椎弓根螺钉内固定系统治疗68例，胸椎15例，腰椎3例，不同程度神经操作57例。59例同时行椎板切除减压。结果：椎体高度完全恢复53例，达到正常椎体高度的90％ 11例，达到正常椎体高度的80％4例。结论：采用AF内固定手术系统，通过坚固有效的后中前柱复合固定，重建脊柱稳定，恢复腰椎高度和腰椎生理弯曲，扩大椎管容积，并且因术后可早期活动，固定范围小，有利于正常腰椎的活动，从而促进骨折的愈合，经临床应用效果较好，是一种治疗胸腰椎骨折脱位，减少脊髓继发损害，恢复生理功能的有效方法。     

AF系统治疗胸腰椎骨折脱位

目的：回顾性分析AF椎弓根螺钉内固定系统治疗胸腰椎骨折脱位脊髓损伤的效果。方法：采用AF钉治疗48例,胸椎9例,腰椎39例,不同程度神经损伤40例。39例同时行椎板切除减压。结果：椎体高度完全恢复33例,＞90％ 10例,＞80％ 4例;术后神经功能恢复按Frankel标准,除1例B级及2例A级无恢复外,余37例均有不同程度的提高。结论：AF钉固定可靠,操作简单,能达到良好的复位及减压的目的,是一种治疗胸腰椎骨折脱位的有效方法。     

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.     

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.     

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.     

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.     

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.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.