上颈椎术后颈椎矢状位参数变化及影响因素

目的:分析寰枢椎脱位患者上颈椎术后颈椎矢状位参数变化及影响因素。方法:对2011年3月至2022年7月行上颈椎手术的15例寰枢椎脱位患者进行回顾性分析,统计所有患者的基本信息及术前与末次随访的矢状位参数,包括枕颈角(C0-C2 Cobb角)、下颈椎曲度(C2-C7 Cobb角)、T1倾斜角、颈椎矢状面轴向垂直距离(C2-C7 SVA),并进行统计学分析。结果:末次随访时患者的C2-C7 Cobb角为15.18°±12.41°,小于术前的24.30°±15.57°;末次随访时患者的T1倾斜角为28.09°±15.20°,大于术前的24.14°±15.59°,差异均有统计学意义(P均<0.05)。末次随访时患者C0-C2 Cobb角和C2-C7 SVA增大,但与术前相比差异无统计学意义(P均>0.05)。ΔC2-C7 Cobb角与术前C2-C7 Cobb角的大小有关,差异有统计学意义(P<0.05)。术前C2-C7 Cobb角>20°的患者术后均出现不同程度的下颈椎曲度减小。结论:接受上颈椎手术的寰枢椎脱位患者术后可能出现下颈椎曲度减小,术后下颈椎曲度的丢失与术前C...     

C3-7单开门椎管扩大成形术后颈椎矢状位序列的变化及其与颈椎功能的相关性

目的:探究颈椎单开门椎管扩大成形术后全颈椎矢状位序列的变化,探讨颈椎矢状位序列变化的意义及其与患者颈椎功能状态的关系。方法:回顾性分析我院2015年1月～2018年7月收治的脊髓型颈椎病患者164例,其中男性95例,女性69例,年龄64.8±18.3(48～86)岁。随访时间22.7±11.3(9～46)个月。所有患者均行C3-7后路单开门椎管扩大成形术。在患者术前和末次随访的颈椎侧位X线片上测量颈椎矢状位序列参数:C1-2 Cobb角、C2-7 Cobb角、颈椎弧弦距(cervical arc chord distance,CACD)、颈倾角(cervical tilting,CERT)、颅倾角(cranial tilting,CRAT)、颈总角(cervical global alignment,CGA)、T1倾斜角(thoracic 1 slope,T1S),C7倾斜角(C7 slope,C7S)和C2-7矢状垂线轴(C2-7 sagittal vertical axis,SVA)。记录入组患者术前及末次随访时颈痛视觉模拟评分(visual analog scale,VAS)及改良日本骨科协会评分(modified Japanese Orthopaedic Association,mJOA)评分,采用配对样本t检验比较手术前后各参数的变化,Pearson相关性分析颈椎矢状位序列参数变化之间的相关性及与颈椎功能状态评分(颈痛VAS、mJOA评分)的相关性。结果:颈椎单开门椎管扩大成形术后T1S较术前减小1.25°±3.34°(21.38°±7.54°vs 20.13°±7.16°,P=0.004),C7S较术前减小0.44°±4.23°(28.05°±7.72°vs 27.61°±7.81°,P=0.012),C2-7 Cobb角较术前减小5.51°±6.88°(15.92°±12.57°vs10.40°±10.93°,P0.001),CACD较术前减小1.50±3.92mm (6.94±5.69mm vs 5.44±5.52mm,P=0.003),CERT较术前减小2.23°±5.27°(13.45°±6.37°vs 11.22°±6.78°,P=0.001),C2-7 SVA较术前增大3.35±9.90mm (18.20±9.05mm vs 21.55±10.65mm,P=0.009),C1-2 Cobb角较术前增大2.06°±5.09°(39.56°±0.46°vs 41.62°±0.70°,P=0.002)。末次随访VAS(1.52±1.47分)显著高于术前(1.02±1.12分,P=0.007)。Pearson相关性分析显示C2-7SVA、CACD、CGA、C2-7 Cobb角、C1-2 Cobb角、CERT、CRAT的变化相互之间有显著统计相关性(P0.05)。手术前后VAS的变化与C2-7 SVA (r=0.462,P0.001)、C1-2 Cobb角(r=0.362,P0.01)及CRAT (r=0.323,P0.01)的变化呈正相关,与CGA(r=-0.316,P0.01)及CACD变化(r=-0.344,P0.01)呈负相关,mJOA评分手术前后的变化与C2-7 SVA(r=0.273,P0.05)及C1-2 Cobb角(r=0.298,P0.05)的变化呈正相关。结论:C3-7单开门椎管扩大成形术后出现下颈椎生理曲度变直,头部重心位置前移,上颈椎及颈胸段脊柱过伸。C3-7单开门椎管扩大成形术后轴性症状加重与颈椎矢状位序列的变化有关。     

颈椎后纵韧带骨化症单开门椎管扩大成形术后颈椎矢状位参数变化与疗效的关系

目的 :探讨颈椎后纵韧带骨化症(OPLL)患者行颈后路单开门椎管扩大成形术后颈椎矢状位参数变化与手术疗效的关系。方法:选取2009年1月~2013年1月在我院接受颈后路单开门椎管扩大成形术的OPLL患者68例,随访12~30个月。记录手术前后JOA(Japanese Orthopaedic Association)评分、颈肩臂疼痛VAS(visual analog scale)评分,计算神经功能JOA改善率(improvement rate,IR)。术前、术后和随访时行颈椎正侧位X线片、CT三维重建和MRI检查,测量术前及随访时的颈椎矢状位参数,包括C2-C7 Cobb角、C2-C7矢状面轴向距离(sagittal vertical axis,SVA)和T1倾斜角。结果:末次随访时JOA评分及VAS评分较术前明显改善(P0.001),神经功能恢复为优者21例,良30例,中14例,差3例,优良率为75%。末次随访时C2-C7 Cobb角由术前的15.4°±9.5°增大到17.4°±10.2°,但差异无统计学意义(P=0.166);C2-C7 SVA由术前的21.0±15.3mm增大到27.0±15.7mm,差异有统计学意义(P=0.009);T1倾斜角由术前的30.2°±10.1°增大到33.7°±8.0°,差异有统计学意义(P=0.044)。术前T1倾斜角与C2-C7 Cobb角正相关(r=0.569,P0.01),与C2-C7 SVA正相关(r=0.544,P0.01)。C2-C7 Cobb角与C2-C7 SVA无显著相关性(r=0.05,P=0.798)。末次随访时C2-C7 Cobb角较术前增大24例,较术前减小44例,两组JOA评分和VAS评分变化、神经功能改善率无统计学差异;C2-C7SVA增加46例,减小22例,两组JOA评分和VAS评分变化、神经功能改善率亦无统计学差异(P0.05)。结论 :颈后路单开门椎管扩大成形术治疗OPLL短期疗效确切,手术前后颈椎矢状参数的变化与患者的临床疗效无显著相关性。     

颈椎前路融合后邻近节段退变与矢状位参数

[目的]探讨颈椎前路椎间盘切除融合术后邻近节段退变与颈椎矢状位参数的相关性。[方法]回顾分析2012年1月～2017年12月在广西中医药大学第一附属医院脊柱外科因脊髓型颈椎病接受颈椎前路单节段椎间盘切除融合术(ACDF)且随访资料完整的76例患者,依据随访期间是否出现邻近节段退变分为退变组和无退变组。比较两组患者性别、年龄、体质量指数等一般资料,以及颈椎矢状位C2-7Cobb角、手术节段Cobb角、C2-7矢状位轴向距离、胸廓入口角、TI倾斜角、颈部倾斜角等参数。[结果] 76例中,31例发生ASD,占40.79%;45例未发生ASD,占59.21%。两组患者在性别构成、年龄、BMI、随访时间和手术节段的差异均无统计学意义(P>0.05)。对术前两组患者之间的C2-7Cobb角、手术节段Cobb角、C2-7SVA、TIA、T1S、NT、T1S<19.5°等参数进行比较,差异均无统计学意义(P>0.05)。末次随访时退变组的C2-7Cobb角、手术节段Cobb角、T1S均显著小于无退变组,差异具有统计学意义(P<0.05);而两组患者之间C2-7SVA、TIA和NT的差异均无统计学意义(P>0.05)。此外,术后退变组中T1S<19.5°的患者比例明显高于无退变组,差异具有统计学意义(P<0.05)。T1S<19.5°是发生邻近节段退变的危险因素,相对危险度为1.892,95%置信区间为1.140-3.138。[结论]颈椎前路单节段椎间盘切除融合术后邻近节段退变与颈椎矢状位参数密切相关,手术节段Cobb角恢复不良导致C2-7Cobb角的丧失,进而引起颈椎矢状位失衡是引起ACDF术后发生ASD的原因之一。     

颈椎前路椎间盘切除减压不同融合节段对脊柱-骨盆矢状位平衡的影响

目的探讨颈椎前路椎间盘切除减压椎间融合术(anterior cervical discectomy and fusion,ACDF)术中融合节段数量对脊柱-骨盆矢状位平衡的影响。方法回顾分析2010年1月—2016年12月326例因脊髓型颈椎病接受ACDF治疗的患者临床资料。男175例,女151例;年龄34~81岁,平均56岁。融合节段:单节段69例,双节段85例,三节段90例,四节段82例。患者术前及术后12个月摄脊柱全长正侧位X线片,测量并比较脊柱-骨盆矢状位参数,包括:C_(0~2) Cobb角、C_(2~7) Cobb角、C_(2~7)矢状垂直距离(C_(2-7) sagittal vertical axis,C_(2-7) SVA)、T_1倾斜角(T_1 slope,T_1S)、胸廓入口角(thoracic inlet angle,TIA)、胸椎后凸角(thoracic kyphosis,TK)、腰椎前凸角(lumbar lordosis,LL)、骨盆入射角(pelvic incidence,PI)、骶骨倾斜角(sacral slope,SS)、C7矢状位平衡(C7sagittal vertical axis,C7 SVA)、T_1骨盆角(T_1 pelvic angle,TPA)。比较术前及术后12个月颈椎日本骨科协会(JOA)评分、颈椎及上肢疼痛视觉模拟评分(VAS)。对手术前后LL、PI、SS、C7 SVA及TPA进行Pearson相关性分析,评估ACDF术后下腰段脊柱-骨盆拟合关系变化。结果 326例患者术后均获随访,随访时间12~32个月,平均18.5个月。随访期间内固定物在位,无脊髓神经及周围软组织损伤。术后12个月JOA及颈椎VAS评分均较术前显著改善(P0.05),双上肢VAS评分与术前比较差异无统计学意义(P0.05)。4组间术前颈椎VAS评分及术后12个月JOA评分比较差异有统计学意义(P0.05)。术后12个月,单节段融合组各脊柱-骨盆矢状位参数与术前比较,差异均无统计学意义(P0.05)。双节段、三节段及四节段融合组C_(0~2) Cobb角、C_(2~7) Cobb角、C_(2-7)SVA、T_1S、TIA、C7 SVA及TPA均较术前显著增加(P0.05)。4组间比较术前及术后12个月C_(0~2) Cobb角、C_(2~7)Cobb角、T_1S、C7 SVA及TPA差异有统计学意义(P0.05)。术后12个月双节段、三节段、四节段融合组的C7 SVA及TPA改变量均显著大于单节段融合组(P0.05);双节段、三节段、四节段融合组间比较差异无统计学意义(P0.05)。手术前后各组PI与LL、SS均成正相关(P0.05)。结论脊髓型颈椎病患者具有生理状态下腰椎与骨盆正常拟合关系,而且ACDF不能改变这一特定关系;单节段融合后脊柱-骨盆矢状位序列无变化,而双节段及多节段融合后脊柱-骨盆矢状位平衡改变。     

后路寰枢椎融合术后颈椎矢状面参数变化及相关因素分析

目的:测量后路寰枢椎融合手术对颈椎矢状面参数的变化,并对其相关影响因素进行评估。方法:回顾性研究2015年1月～2017年12月收治的寰枢椎脱位病例18例,男8例,女10例,年龄25～72岁,平均49.6±13.7岁。所有寰枢椎脱位患者均行单纯后路复位C1～C2固定融合术,随访时间为5～17个月,平均7.4±3.7个月。测量患者术前和末次随访时的枕颈角(C0～C2角)、下颈椎前凸角(C2～C7角)、颈椎前凸角(C0～C7角)、颈椎矢状面轴向垂直距离(C2-C7 sagittal vertical axis,C2-C7 SVA)、C1～C2角、T1倾斜角(T1 slope,T1S)、颈部倾斜角(neck tilt,NT)和胸廓入口角(thoracic inlet angle,TIA)等颈椎矢状面参数。在末次随访时,术后C2～C7角比术前减小的病例归为下颈椎前凸曲度减小组(5例),而术后C2～C7角比术前增加或不变的病例纳入下颈椎前凸曲度增加组(13例)。采用卡方检验做下颈椎前凸曲度减小与性别、年龄(以60岁为界限)、术前T1S(以25°为界限)、术前C2-C7 SVA(以15mm为界限)、术前TIA(以70°为界限)、术前C2-C7角(以20°为界限)、术前C0-C2角(以20°为界限)、术前C0-C7角(以45°为界限)和术后C1-C2角(以20°为界限)等临床因素相关性的单因素分析。采用Logistic回归对术后下颈椎前凸曲度减小的相关因素进行多因素分析。结果:所有患者术前和末次随访时的C0～C2角分别为21.6°±16.4°和28.3°±8.6°、C2～C7角分别为15.3°±12.9°和16.4°±11.1°、C0～C7角分别为36.8°±19.7°和44.9°±13.2°、C1～C2角分别为12.4°±17.6°和17.5°±7.3°、C2～C7 SVA分别为13.4±14.7mm和15.1±11.7mm、T1S分别为22.8°±8.2°和23.5°±7.3°、NT分别为50.8°±9.5°和51.9°±8.9°、TIA分别为73.6°±11.1°和75.4°±10.0°,以上这些颈椎矢状面参数在术前与末次随访的比较均无显著性差异(P0.05)。对两组患者术前和末次随访的颈椎矢状面参数进行比较,前凸减小组的术前C2～C7角明显大于前凸增加组(27.6°±10.5°vs 10.5°±10.5°,P0.05),余参数比较无统计学差异。单因素卡方分析显示术后下颈椎前凸曲度减小与术前C2～C7角≥20°有关(χ~2=4.923,P=0.026),多因素Logistic回归分析显示术前C2～C7角≥20°并不是独立危险因素(OR=0.147,P=0.225)。结论:后路寰枢椎融合术后有可能发生下颈椎前凸曲度减小,而术前C2-C7角≥20°是术后下颈椎前凸曲度减小的危险因素。     

不同类型颈椎病患者颈伸肌肌容量与颈椎矢状位参数的差异及相关性研究

目的 :探讨不同类型颈椎病患者之间颈伸肌肌容量与颈椎矢状位序列的差异及相关性。方法 :回顾性分析2016年5月～2018年7月就诊于北京大学国际医院的颈椎病患者563例,其中男性304例,女性259例,平均年龄53.3±19.6岁,根据颈椎病的类型分为A组(脊髓型颈椎病,n=208)、B组(神经根型颈椎病,n=194)和C组(颈型颈椎病,以轴性症状为主且无神经受压的临床症状或体征,n=161)。所有患者行颈椎MRI及颈椎侧位X线片检查。通过PACS (picture archiving and communication systems)系统在颈椎侧位X线片上测量颈椎矢状位参数序列:C2-7 Cobb角、C0-2 Cobb角、C7斜率(C7 slope,C7S)和C2-7矢状垂直轴(C2-7 sagittal vertical axis,C2-7 SVA)。通过Image J软件对MRI轴位像上C3～7上终板水平浅层颈伸肌截面积(superficial extensor area,SEA)、深层颈伸肌截面积(deep extensor area,DEA)与相应颈椎椎体截面积(vertebra body area,VBA)的比值进行了测量和分析,以SEA/VBA及DEA/VBA作为颈伸肌肌容量。采用ANOVA单因素方差分析对组间矢状位参数,颈伸肌肌容量进行对比(组间两两对比采用Games-Howell法),采用Pearson相关性分析对颈伸肌肌容量与矢状位参数关联性进行分析。结果:C2-7 Cobb角A组(8.64°±6.19°)显著低于B组(12.55°±6.27°,P0.05)及C组(13.08°±5.77°,P0.05);C7S A组(28.09°±10.16°)显著高于B组(22.26°±7.55°,P0.05)及C组(21.63°±8.96°,P0.01);C2-7 SVA A组(21.77±12.38mm)显著高于B组(17.80±10.82mm,P0.05)及C组(15.54±6.82mm,P0.01)。SEA/DEA比值各组之间无显著统计学差异,A组患者DEA/VBA比值明显低于B、C组(P0.05),其中以C3-5水平差异最为显著(P0.05)。Pearson相关分析显示A组C3 DEA/VBA比值与C2-7 SVA (r=-0.379,P0.05)及C7S (r=-0.311,P0.05)呈弱负相关,C4水平DEA/VBA比值与C2-7 SVA (r=-0.478,P0.01)及C7S(r=-0.466,P0.01)呈中度负相关,而SEA/VBA比值与矢状位参数未表现出显著统计学相关性。结论:脊髓型颈椎病患者的颈椎矢状位序列较其他类型颈椎病表现出显著的失平衡改变,脊髓型颈椎病患者的深层颈伸肌体积显著低于其他类型的颈椎病,深层颈伸肌近头端附着区域的体积与C2-7 SVA及C7S之间存在一定程度的负相关性。     

C_7倾斜角与短节段颈前路椎间盘切除融合术后颈椎矢状位参数的影像学相关性分析

目的通过影像学测量探讨短节段颈前路椎间盘切除融合术(anterior cervical discectomy with fusion,ACDF)中术前C_7倾斜角(C_7 slope,C_7S)与颈椎矢状位参数变化的关系。方法回顾分析2012年1月—2017年1月收治的54例因颈椎病接受ACDF治疗的患者临床资料。其中男24例,女30例;年龄23～71岁,平均46.6岁。神经根型颈椎病29例,脊髓型颈椎病25例。病程3～48个月,平均16.8个月。单节段ACDF 44例,双节段ACDF 10例。在术前及末次随访时的颈椎X线片上测量颈椎矢状位参数:C_(2～7)Cobb角、C_(2-7)矢状位垂直距离(C_(2-7) sagittal vertical axis,C_(2-7) SVA)、C_7S和手术节段Cobb角(segment Cobb angle,SCobb),并计算C_(2～7)Cobb角变化值(末次随访与术前角度的差值)。术前及末次随访时采用Pearson相关分析各参数之间的相关性。根据术前C_7S中位数(15°)分为A组(C_7S15°)和B组(C_7S≥15°),比较两组手术前后各矢状位参数差异。结果 54例患者均获随访,随访时间6～45个月,平均15.5个月。末次随访时患者C_7S、C_(2～7)Cobb角、C_(2-7) SVA及SCobb角均较术前显著改善(P0.05)。相关性分析显示,术前C_7S和SCobb角均与C_(2～7)Cobb角和C_(2-7) SVA有显著相关性(P0.05),而C_7S与SCobb角之间无显著相关性(r=0.049,P=0.724);末次随访时,C_7S、C_(2～7)Cobb角、SCobb角之间均有显著相关性(P0.05),而C_7S和SCobb角与C_(2-7) SVA之间均无显著相关性(P0.05)。根据患者术前C_7S中位数分组,A组28例,C_7S为(11.82±3.60)°;B组26例,C_7S为(20.77±4.09)°;两组患者性别及年龄比较差异均无统计学意义(P0.05)。A组术前C_(2～7)Cobb角和C_(2-7) SVA显著小于B组(P0.05),术前SCobb角与B组比较差异无统计学意义(t=0.234,P=0.816)。末次随访时A、B组间C_(2～7)Cobb角、C_(2-7) SVA和SCobb角比较差异均无统计学意义(P0.05);但A组C_(2～7)Cobb角变化值显著大于B组(t=2.321,P=0.024)。结论术前C_7S≥15°者其术前有更多的生理前凸,但其术后颈椎曲度变化较小,即短节段ACDF更有利于矫正术前C_7S15°的颈椎曲度。     

早发型脊柱侧凸行生长棒矫正手术后颈椎矢状位参数变化及颈椎矢状位失平衡的风险因素分析

目的 探讨早发型脊柱侧凸(early onset scoliosis,EOS)行生长棒矫正手术前后的颈椎矢状位参数变化,并分析颈椎矢状位失衡的风险因素,为临床及早制定干预措施提供参考.方法 回顾性分析2013年7月-2018年7月在本院骨科接受生长棒矫正手术的41例EOS患儿资料,统计患者人口学资料、手术情况等临床资料;并分别于手术前、术后及末次随访时,在脊柱全长正侧位X片上测量其颈椎矢状位参数(T1 S、C2-7 Cobb角、C2-7 SVA等);此外,测量患儿手术前后的胸椎后凸角(thoraco-lumbar kyphosis,TK),腰椎前凸角(lumbar lordosis,LL),胸弯/胸腰弯Cobb角,以及最大后凸Cobb角,C7-S1的SVA参数值,计算其生长棒术后的胸弯矫形率、最大后凸Cobb角矫形率.对41例EOS患儿手术前、术后、末次随访时的颈椎矢状位参数变化情况进行分析,并依据C2-7 SVA值进行颈椎矢状位失衡与否的判定,进行潜在风险因素的组间单因素分析和多因素Logistic回归分析.结果 与术前相比,41例EOS患者末次随访时的T1 S、C2-7 Cobb角、C2-7 SVA值均显著升高,差异有统计学意义(P<0.05);以C2-7 SVA值进行判定,41例中,13例随访期间出现颈椎矢状位失衡(失衡组),另28例颈椎矢状位平衡在正常范围(正常组).经单因素分析,正常组患儿的年龄、T1 S变化值、PJK占比均明显小于失衡组;正常组的体质量指数、最大后凸角矫正率均明显大于失衡组.将上述因素纳入多因素Logistic回归分析,近端交界性后凸(proximal junctional kyphosis,PJK)(OR=11.293,P=0.000)是EOS患儿生长棒术后颈椎矢状位失衡的独立风险因素.结论 生长棒矫正手术对EOS患儿的颈椎矢状位参数可产生一定影响,其中术后有PJK者应警惕出现颈椎矢状位失衡的风险.     

颈椎后路单开门椎管扩大成形术对颈椎矢状平衡的影响

目的观察颈椎后路单开门椎管扩大成形术对颈椎矢状平衡的影响及各矢状平衡参数与临床恢复效果的相关性,探索可以预测术后疗效的平衡参数。方法回顾性分析2012-01-2013-04于长征医院脊柱外科行颈椎后路单开门椎管扩大成形术51例患者的影像学资料及临床资料,其中男性34例,女性17例,平均年龄52.8岁。比较术前、术后各矢状平衡参数及临床疗效指标的变化,探究各矢状平衡参数之间及其与临床恢复指标的相关性。结果随访时间为7-24个月,平均16.4个月。术前JOA评分平均8.9分,术后平均13.1分,平均神经功能改善率为51.8%。术前矢状平衡参数:C_0-C_2 Cobb角为(21.4±1.1)°,C_2-C_7 SVA为(25.3±1.2)mm,T_1-Slope为(25.1±1.2)°;术后末次随访时:C_0-C_2 Cobb角为(24.2±1.0)°,C_2-C_7 SVA为(29.2±1.5)mm,T_1-Slope为(28.5±1.4)°,三项参数术后较术前变化均有统计学意义。术前NDI、VAS及SF-36评分分别为(22.1±5.2)分、(2.9±1.2)分和(41.3±6.5)分;术后末次随访时以上评分分别为(11.7±5.1)分,(1.3±0.9)分,(52.4±6.8)分,三种评分术后较术前变化均有统计学意义。术后C_0-C_2 Cobb角增加值及术后T_1-Slope增加值均与C_2-C_7 SVA增加值呈正相关,术前C_2-C_7 SVA与术后JOA评分呈负相关。结论颈椎后路单开门椎管成形术对于颈椎矢状平衡产生明显的影响,术后颈椎有发生前倾趋势。对于术前存在高C_2-C_7 SVA的患者,术后发生颈椎矢状平衡失衡的危险性增加,严重的颈椎矢状平衡失衡可导致患者颈部疼痛、功能障碍及生活质量下降。     

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.     

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.     

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.