胸椎椎体后缘骨内软骨结节的发生特点与手术治疗

目的探讨胸椎椎体后缘骨内软骨结节的特点以及软骨结节切除术与改良全脊髓减压术的疗效。方法1978年5月至2005年5月,手术治疗胸椎椎体后缘骨内软骨结节32例,男18例,女14例;年龄23～70岁,平均47.8岁。X线片可见损伤终板后上或后下缘的骨赘、游离骨块、缺损;CT轴位片可见突向椎管的环形或块状骨化影,其内为低密度区;MRI可见脊髓受压,但无法分辨骨性终板与软骨终板。前20年的6例分别采用传统全椎板减压术、侧前方减压术、整块半关节突全椎板减压术治疗各2例;后6年采用软骨结节切除术治疗21例、改良全脊髓减压术治疗5例。结果32例中31例发生于胸腰段、1例位于T8。共发生胸椎椎体后缘骨内软骨结节37处,椎体上终板30处、下终板7处;单一椎体终板发病者27例、相邻椎体上下终板同时发病者4例、跳跃性两处发病者1例。32例中合并胸椎黄韧带骨化者16例,7例与胸椎椎体后缘骨内软骨结节发生于同一椎间、9例发生于与软骨结节上下相邻及其以远椎间。黄韧带骨化按CT分型,棘状型与结节型11例、板块型与隆突型5例。随访26例,随访时间1～27年,平均3.8年。按Otanni分级方法,优22例(84.6%)、良3例(11.5%)、可1例(3.9%)。结论胸椎椎体后缘骨内软骨结节多发于胸腰段椎体的上终板,且常常合并胸椎黄韧带骨化;软骨结节切除术与改良全脊髓减压术是治疗该病的安全、有效术式。     

胸椎管狭窄症术后并发症的防治

目的探讨胸椎管狭窄症术后并发症的发生与防治。方法1985年1月至2005年1月手术治疗283例胸椎管狭窄症患者。胸椎黄韧带骨化症123例、胸椎后纵韧带骨化症73例、胸椎间盘突出症54例、弥漫性原发性骨肥厚症19例、椎体后缘骨内软骨结节14例。1996年以前均采用后入路,枪式咬骨钳切除椎板,咬除骨化的黄韧带或关节突的内1/2,为原始方法;1996年后,椎间盘突出或合并后纵韧带骨化、椎体后缘骨内软骨结节者采用经胸腔入路。黄韧带骨化、弥漫性原发性骨肥厚,采用后入路,应用磨钻加"揭盖法"切除椎板,在神经剥离子的保护下,应用骨凿切除关节突的内1/2,为改进方法。分别观察两组围手术期、中远期和供骨区并发症发生情况,并进行对比。结果随访254例,随访时间1~19年,平均6年2个月。并发症发生率42.1%,原始方法(65.2%)明显高于改进方法(23.2%)。各种并发症中脊髓损伤和硬脊膜损伤的发生率两组差异有统计学意义(P<0.05)。结论脊髓损伤导致症状加重是灾难性的并发症。采用改进方法手术治疗胸椎管狭窄症可减少并发症的发生。     

胸椎结核外科治疗不同术式选择探讨

目的探讨不同解剖节段胸椎结核外科治疗术式的选择策略及疗效。方法回顾分析2005年5月至2009年5月手术治疗36例成人胸椎结核的临床资料,其中男19例,女17例;年龄17~60岁,平均32.2岁;病变破坏2个椎体23例,3个椎体7例,4个椎体6例。术前所有患者均有不同程度的后凸畸形,后凸角10°~110°,平均21°。22例伴有神经功能障碍。将胸椎按照解剖特点分为颈胸结合部(C7~T2)、中部(T3~5)、下胸椎(T6~12)。依据解剖特点不同采用5种不同的手术入路(颈胸结合部前入路、经胸腔胸膜外入路、开胸、肋横突旁入路、后正中入路)对36例胸椎结核患者行一期病灶清除、植骨融合内固定术。结果所有患者随访18~48个月,平均26个月,术后胸背部疼痛减轻,切口一期愈合,术后1~3个月血沉逐渐恢复正常,术后后凸角度矫正至0°~60°,平均14°,自体骨植骨于术后3个月开始融合,22例伴有神经功能障碍者,术后Frankel分级提高1~2级,大部分完全恢复。结论根据胸椎结核病灶部位的解剖特点、累及的范围选择恰当的术式可有效清除结核病灶,矫正后凸畸形,重建脊柱的稳定性,改善神经功能,临床效果良好。     

一期后路内固定病灶清除植骨融合治疗上胸椎结核

目的探讨一期后路椎弓根钉内固定、病灶清除、植骨融合治疗上胸椎结核的临床疗效。方法自2009年3月至2011年1月,应用脊柱后正中切口一期行椎弓根钉内固定、切除肋骨头及横突行侧前方病灶清除、植骨融合治疗上胸椎结核12例,其中男10例,女2例;年龄9~45岁,平均36.2岁;病变节段:T2~31例,T3~52例,T4~66例,T5~62例,T61例;所有患者均以胸背部疼痛首诊并伴不同程度的神经功能障碍,术前后凸角15°~52°,平均30.2°;Frankel分级B级2例,C级2例,D级8例;入院时查血沉平均71 mm/h,术前血沉平均35 mm/h。结果术后随访6~22个月,1例患者手术切口皮缘坏死经换药后愈合,余患者均一期愈合。术后1~3个月内血沉恢复至正常水平,胸椎后凸畸形均明显改善。术后后凸角度10°~27°,平均19°;植骨融合时间4~7个月,平均5个月,至终末随访时无结核复发及内固定相关并发症。末次随访时2例Frankel分级B级者恢复至C级,2例C级者1例恢复至D级,1例恢复至E级,8例D级恢复至E级。结论一期后路椎弓根内固定、病灶清除、植骨融合治疗上胸椎结核手术入路简单,创伤小,有利于恢复脊柱稳定性,矫正后凸畸形,且操作安全,并发症少。     

前方入路手术治疗上胸椎转移瘤

目的:探讨前方入路行上胸椎肿瘤切除、椎体重建、钛板内固定的技术及方法,分析手术治疗效果及相关并发症。方法:2004年6月~2011年7月我科收治上胸椎(T1~T4)转移瘤患者17例,其中男6例,女11例,年龄55,1±7.3岁(47~68岁)。术前神经功能按Frankel分级:B级3例,C级4例,D级8例,E级2例。肿瘤位置:T1 7例,T2 5例,T3 3例,T4 2例。按Tokuhashi脊柱转移瘤评分系统评分为9~12分;根据WBB分区理论肿瘤病灶位于4~9区。对于T1椎体病灶患者采用低位下颈椎前方入路;对于T2~T4椎体病灶患者采用前方劈开胸骨经头臂干外侧间隙入路。结果:所有患者均能很好耐受手术,低位下颈椎前方入路手术时间为94.1士5.0min(90~102min),出血量为186.6±100.2ml(100~400ml);前方劈开胸骨经头臂干外侧间隙入路手术时间为121.0±165(100~150min),出血量为352.0±134.4ml(220~600ml)。术后病理学检查:6例来源于肺癌,5例来源于乳腺癌,2例来源于甲状腺癌,2例来源于胃肠道癌,2例来源不明。术后2例前方劈开胸骨经头臂干外侧间隙入路手术患者出现肺部感染、肺不张,经对症治疗后治愈。3例(其中1例为低位下颈椎前方入路手术患者)出现喉返神经牵拉伤致一过性声音嘶哑,术后1个月内声音恢复正常。随访19.7±9.8个月(6~48个月),9例患者神经功能有不同程度改善,其中3例Frankel分级B级患者2例改善为E级,1例改善为D级;4例C级2例改善到E级,2例改善到D级;2例D级患者改善到E级。5例患者在术后6~14个月因多处转移、全身衰竭死亡。结论:前方入路是治疗上胸椎转移瘤可供选择的有效入路,该入路可以充分显露前方椎体病变,有效切除病灶,彻底解除来自脊髓前方的压迫,改善患者症状。     

经肋椎关节手术入路治疗胸椎多椎体结核的临床研究

目的 探讨后路经肋椎关节入路病灶清除、内固定、植骨融合治疗胸椎多椎体结核的临床效果.方法 回顾分析2005年7月~2011年7月,采用后路经肋椎关节病灶清除、内固定、植骨融合手术治疗的胸椎多椎体结核患者43例,术前及末次随访时行Frankel评分,观察随访期间植骨融合率、后凸畸形矫正状况.结果所有患者均获得随访,时间7个月~5年,末次随访时1例Frankel A级患者恢复至Frankel D级,3例Frankel B级患者恢复至Frankel D级,其余患者均恢复至Frankel E级.随访期间所有患者均取得骨性融合,融合时间3~12个月.术后1周Cobb角平均为5.1°,末次随访Cobb角平均为9.2°,Cobb角平均丢失约4.1°.结论 经肋椎关节手术入路治疗胸椎多椎体结核是一种较为理想的手术方式.     

胸椎椎弓根螺钉治疗上胸椎严重骨折

目的：探讨胸椎椎弓根螺钉治疗上胸椎严重骨折的方法及疗效。方法：自2000年3月至2008年6月回顾性分析18例上胸椎严重骨折患者的临床资料,男10例,女8例;年龄20～76岁,平均34.3岁。按Denis分型：爆裂骨折15例,骨折伴脱位3例。损伤节段：T1-T22例,T32例,T3-T42例,T4-T58例,T5-T62例。Wolter外伤性椎管狭窄分型：Ⅰ型9例,Ⅱ型7例,Ⅲ型2例。Frankel分级：A级5例,B级4例,C级2例,D级4例,E级3例。均采用后路胸椎椎弓根螺钉固定治疗,手术前后通过影像观察Cobb角及椎管狭窄度,通过Frankel分级的变化评估神经症状,通过CT复查术后椎弓根螺钉与椎弓根的位置。结果：18例患者均获随访,时间1～6年,平均2.3年。Cobb角由术前的（26.50±5.62）°改善为术后的（21.20±3.54）°（P〈0.05）;椎管内占位改善率61%。术后Frankel分级：A级4例,B级2例,C级3例,D级3例,E级6例,手术前后Frankel分级有明显改善（P〈0.05）。CT复查示椎弓根螺钉88.5%（69/78）位于椎弓根内。结论：后路椎弓根螺钉固定方法是坚强、安全、有效的胸椎严重骨折的治疗方法。     

后外侧入路减压椎间植骨融合内固定治疗胸椎管狭窄症的疗效及安全性

【摘要】 目的：探讨后外侧入路减压、椎间植骨融合、椎弓根螺钉内固定手术治疗胸椎管狭窄症的疗效及安全性。方法：2006年1月～2012年3月,收治单节段腹侧压迫致胸椎管狭窄症患者22例,男14例,女8例,年龄33～69岁,平均53.5岁。病程1~18个月,平均6.7个月。椎间盘突出部位：T7/8 1例,T8/9 4例,T9/10 9例,T10/11 8例。术前脊髓功能Frankel分级：B级5例,C级11例,D级6例。所有患者均行后外侧入路减压、椎间植骨融合、椎弓根螺钉内固定手术。采用Otani等评分系统进行术后疗效评估并计算临床优良率,评价治疗效果。结果：手术时间2.5~5h,平均3.2h,出血量400~1800ml,平均800ml。2例患者术后即刻有短暂脊髓功能障碍加重,经及时给予甲基强的松龙冲击、消肿、营养神经等治疗,分别于术后8h及24h开始逐渐恢复,其余20例患者术后即刻脊髓功能较术前恢复。术后随访24～60个月,平均40个月。末次随访时所有患者神经功能均明显改善,Frankel分级：C级3例,D级6例,E级13例。根据Otani等分级标准,优13例,良6例,可3例;优良率为86.36%。所有患者均获得骨性融合,均无内固定物松动、断裂等并发症发生。结论：后外侧入路减压、椎间植骨融合、椎弓根螺钉内固定手术治疗胸椎管狭窄症可取得良好的临床疗效,操作安全,并发症少。     

一期后路内固定并病灶清除植骨融合治疗上胸椎结核

目的：探讨一期后路椎弓根钉内固定、病灶清除、植骨融合治疗上胸椎结核的临床疗效。方法自2009年3月至2011年1月,应用脊柱后正中切口一期行椎弓根钉内固定、切除肋骨头及横突行侧前方病灶清除、植骨融合治疗上胸椎结核12例,其中男10例,女2例;年龄9～45岁,平均36.2岁;病变节段：T2～31例,T3～52例,T4～66例,T5～62例,T61例;所有患者均以胸背部疼痛首诊并伴不同程度的神经功能障碍,术前后凸角15°～52°,平均30.2°;Frankel分级B级2例,C级2例,D级8例;入院时查血沉平均71 mm/h,术前血沉平均35 mm/h。结果术后随访6～22个月,1例患者手术切口皮缘坏死经换药后愈合,余患者均一期愈合。术后1～3个月内血沉恢复至正常水平,胸椎后凸畸形均明显改善。术后后凸角度10°～27°,平均19°;植骨融合时间4～7个月,平均5个月,至终末随访时无结核复发及内固定相关并发症。末次随访时2例Frankel分级B级者恢复至C级,2例C级者1例恢复至D级,1例恢复至E级,8例D级恢复至E级。结论一期后路椎弓根内固定、病灶清除、植骨融合治疗上胸椎结核手术入路简单,创伤小,有利于恢复脊柱稳定性,矫正后凸畸形,且操作安全,并发症少。     

经胸骨柄“U”形切除入路治疗上胸椎爆裂骨折并截瘫

目的探讨经胸骨柄“U”形切除入路治疗上胸椎爆裂骨折的可行性及临床疗效。方法12例上胸椎爆裂骨折并截瘫患者，全部采用经胸骨柄“U”形切除入路行伤椎次全切除减压、植骨、颈椎前路钢板内固定术。结果随访1～7年，椎间植骨均愈合好，内固定无松动、断裂，无切口感染、颈前血肿、窒息、气胸、乳糜漏、肺部感染等并发症。9例术后感觉、运动神经功能均有不同程度改善。Frankel分级：术前A级6例术后恢复至B级1例、C级2例、3例无明显改善；B级1例恢复至C级；C级3例恢复至D级2例、E级1例；D级2例恢复至E级。结论经胸骨柄“U”形切除入路解决了低位下颈椎前方入路因胸骨柄遮挡带来的操作不便，又可避免切断胸骨、锁骨的相关并发症。通常能显露至T4，并能在直视下完成T3及以上椎体的前方减压、植骨和钢板内固定，是治疗上胸椎爆裂骨折理想的手术入路。     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

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.     

The multiply injured child

Blunt trauma is the principal cause of childhood death in many developed countries. This review outlines the differences between adults and children with respect to resuscitation and treatment of orthopaedic injuries in a child with polytrauma. Recent advances in techniques of fracture stabilization are reported.     

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.     

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.     

Intravenous endotoxin does not increase tissue extravasation of albumin in rats

Background : It is unclear whether activation of the inducible nitric oxide synthase (iNOS) increases or decreases the extravasation of plasma.
Methods : Chloralose anaesthetised male Wistar rats received E. coli lipopolysacharide (LPS), 3 mg kg^-1 i.v., or the corresponding volume of saline, 3 or 5 h before the end of the experiment. Mean arterial pressure (MAP) and heart rate (HR) were recorded. Tissue clearance of radio-labelled albumin, during the last 2 h of each experiment, was determined by a double-isotope method. In separate animals, the serum concentration of nitrite and nitrate was determined, 5 h after LPS or the solvent.
Main Results : LPS initially decreased MAP and lastingly increased HR. In the 3-h LPS animals (n=8), tissue plasma clearance was lower in the heart and calf muscle and increased only in diaphragm, compared to corresponding control animals (n=8). In the 5-h LPS rats, clearance was lowered (n=8) in the entire gastrointestinal tract and in testes, compared to controls (n=8). The serum nitrite/nitrate concentration was higher in animals given LPS (n=6) than in controls (n=6).
Conclusion : After LPS, tissue clearance of albumin was not increased in any major tissue, in spite of increased serum levels of NO end products. Apparently, after activation of iNOS, the augmented release of NO is not necessarily associated with increased albumin extravasation.     

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery: A randomised, double-blind, cross-over study with and without adrenaline

Background: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. Methods: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml · h^?1 of bupivacaine 1 mg · ml^?1, fentanyl 2 μg · ml^?1, and adrenaline 2 μg · ml^?1 were included. On the 1^st and 2^nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. Results: The number of hypaesthetic dermatomal segments decreased (P <0.001) and pain intensity at rest and when coughing increased (P <0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15–20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng · ml^?1 (P <0.01), and there was more sedation during the period without adrenaline. Conclusions: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.