退变性脊柱侧凸长节段固定矫形融合术后冠状面失平衡相关危险因素分析

【摘要】 目的：探讨退变性脊柱侧凸患者长节段固定矫形融合术后冠状面失平衡的相关危险因素。方法：回顾性分析2014年1月～2017年2月在我院行长节段固定矫形融合术并具有完整影像学及随访资料的61例退变性脊柱侧凸患者。男24例,女37例;年龄53～78岁（59.0±6.1岁）;按鼓楼医院退变性脊柱侧凸分型：A型31例,B型19例,C型11例。固定融合范围：T10~L5 18例,T10~S1 6例,T10~S2 6例,T12~L5 14例,L1~L5 8例,L1~S1 7例,L2~S1 2例。随访18~85个月（平均36.4个月）,根据末次随访时冠状面平衡情况将其分为平衡组和失平衡组,比较两组术前和末次随访时的主弯Cobb角、冠状平衡距离（CBD）、畸形矫正率和术前L5倾斜度、畸形分型、腰弯顶椎位置、顶椎旋转度、截骨级别、固定节段及数量、远端固定椎、腰骶弯Cobb角、主弯Cobb角与腰骶弯Cobb角比值等,将具有统计学差异的指标进行二元Logistic回归分析。结果：61例患者中,末次随访时8例出现冠状面失平衡加重或新发失平衡。两组患者术前主弯Cobb角、CBD、顶椎旋转度、腰弯顶椎位置、截骨级别、固定节段及数量、远端固定椎无统计学差异（P>0.05）,术前腰骶弯Cobb角、术前主弯Cobb角与腰骶弯Cobb角比值、术前L5倾斜角、术后主弯Cobb角、术后CBD、畸形矫正率及畸形分型有统计学差异（P<0.05）。二元逻辑回归分析显示术后冠状面失平衡与术前主弯Cobb角、术前腰骶弯Cobb角、术前L5倾斜度呈正相关,OR值分别为1.158、1.210、1.322（P<0.05）,与畸形矫正率、顶椎旋转度、固定节段数量无显著相关性（P>0.05）。结论：退变性脊柱侧凸长节段固定矫形融合术后可出现冠状面失平衡,术前主弯及腰骶弯Cobb角较大、L5倾斜角较大是退变性脊柱侧凸术后冠状面失平衡或原有失平衡加重的危险因素。     

儿童下腰椎和腰骶段半椎体畸形冠状面平衡状况与外科矫形选择

目的:评估儿童下腰椎及腰骶段半椎体畸形冠状面平衡情况,分析不同外科矫形方式的选择和临床疗效。方法:回顾分析2005年1月~2013年12月我院收治的14例先天性脊柱侧凸患者,平均年龄7.8±3.3岁(3~10岁)。L4半椎体4例,L5半椎体7例,S1半椎体3例。根据术前冠状面平衡情况分为3组:A组冠状面平衡,C7铅垂线偏离骶骨正中平分线(CSVL)≤2cm;B组为C7铅垂线位于半椎体的对侧(偏离CSVL2cm);C组为C7铅垂线位于半椎体的同侧(偏离CSVL2cm)。所有患者均采用一期后路半椎体切除联合椎弓根螺钉内固定矫形植骨融合术式。矫形方式:A组中凸侧与凹侧撑开、压缩力均等;B组半椎体侧单纯压缩;C组增加L5/S1节段"反向"凸侧撑开、凹侧压缩的矫形操作。随访观察各组患者畸形矫正情况。结果:所有病例随访24~68个月,平均33±12个月。术前冠状面排列中平衡4例(29%),失平衡10例(71%)。术前冠状面Cobb角平均36.8°,末次随访时平均12.1°±8.0°(P=0.000),最终矫正率67.1%。术前的冠状面平衡为6~53mm,平均30.6±14.9mm,末次随访时冠状面平衡为0~44mm,平均10.7±10.9mm(P=0.001)。其中,A组患者4例,术前与术后均维持了冠状面平衡;B组患者6例,术后有1例患者冠状面仍然失平衡;C组患者4例,术后均恢复了冠状面平衡。结论:儿童下腰椎和腰骶段的半椎体畸形冠状面失平衡发生率较高,一期后路半椎体切除联合椎弓根内固定、结合不同冠状面排列情况采取恰当矫形方式,可能获得满意的冠状面平衡和临床疗效。     

合并胸腰段后凸的青少年特发性脊柱侧凸的临床研究

目的 探讨合并胸腰段后凸的青少年特发性脊柱侧凸(AIS)的临床特点和手术治疗策略. 方法对2001年1月至2007年1月收治的413例AIS患者进行回顾性分析,合并胸腰段后凸者共10例,其中男2例,女8例;年龄12～18岁,平均14.3岁.侧凸类型包括PUMC Ⅱb2型3例,Ⅱc 3型4例,Ⅱd2型1例,Ⅲb型2例.单纯后路内固定术8例,前路松解+后路内固定术2例.术前、术后及随访时摄X线片,对侧凸类型、Cobb角、顶椎旋转度、顶椎偏距、侧凸柔韧性、胸腰段后凸、冠状面及矢状面躯干偏移进行评测和分析.结果 本组患者中双弯8例,三弯2例;胸腰弯/腰弯Cobb角≥45°者7例,柔韧性指数≤70%者6例,顶椎旋转度≥Ⅱ度者9例.所有病例的融合范围均符合PUMC分型原则.手术前后平均胸弯冠状面Cobb角分别为71.7°和37.4°,平均矫正率为47.8%;手术前后平均胸腰弯/腰弯冠状面Cobb角分别为65.0°和27.8°,平均矫正率为57.2%;手术前后平均胸腰段后凸分别为35.5°和4.2°,平均矫正率为88.2%.全部病例随访12～72个月,平均23.1个月;最终随访时无躯干失平衡发生. 结论 合并胸腰段后凸的AIS一般多为双弯或三弯,胸腰弯/腰弯畸形往往比较严重,并有明显的旋转畸形.对合并胸腰段后凸的AIS,应融合胸腰弯/腰弯以防止术后发生失代偿或后凸加重, PUMC分型可以有效识别病变类型并指导融合范围的选择.     

儿童单节段半椎体切除术后躯干倾斜致肩部失衡的危险因素与转归

目的探讨儿童单节段半椎体切除术后出现肩部失平衡的先天性脊柱侧凸患者远期随访时肩部失衡的危险因素, 以及术后躯干倾斜对肩部失平衡的作用。方法回顾性分析2006年7月至2018年12月接受半椎体切除伴短节段固定融合手术且在术后出现肩部失衡30例先天性脊柱侧凸患者的病历资料, 男16例, 女14例;年龄(4.53±2.05)岁(范围2～8岁);胸椎半椎体10例, 胸腰段半椎体12例, 腰椎半椎体8例。根据末次随访时全脊柱正位X线片测量双侧肩部软组织阴影最高处的垂直高度差, 即双肩高度差(shoulder imbalance, SI) >1.0 cm作为肩部失平衡的标准, 分为肩平衡组与肩失衡组。测量术前、术后3个月及末次随访时SI、冠状面平衡(distance between C7 plumbline and center sacral vertical line, C7PL-CSVL)、主弯Cobb角、主弯近端弯Cobb角(Cobb angle of proximal curve, CAPC)、主弯远端弯Cobb角(Cobb angle of distal curve, CADC),...     

先天性腰骶段脊柱畸形长节段固定术后冠状面失平衡的原因分析

目的 :总结分析先天性腰骶段脊柱畸形行后路长节段固定术后冠状面失平衡原因及预防措施。方法 :回顾性分析2007年5月～2017年5月于我院行后路截骨联合长节段固定矫形术治疗的23例先天性腰骶段脊柱畸形患者的临床资料,其中男6例,女17例,平均年龄13.2±2.8岁(10～18岁),平均随访时间38.2±8.4个月(24～96个月)。收集患者畸形节段、畸形类型、融合节段、躯干倾斜及术前、术后6个月及末次随访时站立位全脊柱X线、Bending位X线、双下肢负重位全长X线片及术前、末次随访时的简体中文版SRS-22评分,测量原发弯和继发弯Cobb角,脊柱柔韧度指数(flexibility of the structural curve,FSC),骶骨倾斜(sacral obliquity,SO),锁骨角(clavicle angle,CA),冠状面平衡距离(coronal balance distance,CBD)与双下肢全长等指标,根据患者矫形术后是否出现冠状面失平衡,将患者分为平衡组与失衡组。冠状面失平衡诊断标准:C7铅垂线(C7plumb line,C7PL)偏距骶骨中垂线(center sacral vertical line,CSVL)2cm。应用卡方检验、t检验,分析术后冠状面失平衡的可能原因并提出相应预防措施。结果:23例患者平均融合节段数7.4±2.3节(5～12节)。术前平均原发弯Cobb角40.25°±10.6°,末次随访时为12.4°±5.2°,平均矫正率(69.1±8.7)%。术前平均继发弯Cobb角35.5°±8.5°,末次随访时为13.1°±5.0°,平均矫正率(63.1±7.9)%。术后冠状面失衡组5例,发生率为21.7%。男2例,女3例。L5半椎体1例,L5半椎体合并L4蝴蝶椎1例,S1半椎体1例,L5横突肥大形成假关节1例,L5楔形椎1例。失衡组中,2例发生S1断钉,1例行翻修手术治疗,1例行支具治疗。两组比较,继发弯柔韧指数、术前躯干偏移、上固定椎位置、下固定椎位置、末次随访冠状面平衡距离(1.0±0.8cm vs 3.0±0.7cm)、术后6个月骶骨倾斜角(3.5°±3.2°vs 15.2°±14.2°)、末次随访锁骨角(3.6±3.6cm vs 15.0±13.3cm)、SRS-22评分末次随访自我形象维度(3.9±0.6 vs 3.7±0.7)、治疗满意度(4.5±0.2 vs 2.6±0.6)、心理健康(4.1±0.4 vs 3.2±0.5)及总评分(15.1±2.8 vs 17.8±2.2)有统计学差异(P0.05)。性别构成比(4/14 vs 2/3)、手术年龄(12.6±3.8 vs 14.2±2.6)、固定节段数(8.3±3.7 vs 6.8±1.9)、术前原发弯Cobb角(35.2°±17.1°vs 37.6°±4.6°)、术后6个月原发弯Cobb角(12.6°±5.6°vs 16.6°±5.9°)、末次随访原发弯Cobb角(12.0°±6.2°vs 16.4°±5.9°)、术前继发弯Cobb角(37.3°±10.7°vs 38.4°±5.4°)、术后继发弯Cobb角(15.5°±4.6°vs 12.0°±7.5°)、末次随访继发弯Cobb角(14.1°±5.0°vs 12.6°±7.5°)、术前冠状面平衡距离(2.1±2.7mm vs 2.9±1.9mm)、术后6个月冠状面平衡距离(0.9±1.2mm vs 1.7±1.1mm)、术前锁骨角(2.0°±0.9°vs 1.2°±1.1°)、术后6个月锁骨角(1.5°±1.2°vs 2.6°±2.4°)、术前骶骨倾斜角(1.1°±1.0°vs 4.0°±2.5°)、SRS-22量表术前功能/活动(4.1±0.5 vs 3.9±0.6)、疼痛(3.4±0.4 vs 3.8±0.4)、自我形象(3.4±0.7 vs 3.2±0.7)、心理健康维度(3.5±0.3 vs 3.6±0.7)、末次随访功能/活动维度(3.9±0.5 vs3.8±0.5)、疼痛维度评分(3.9±0.4 vs 3.7±0.9)均无统计学差异(P0.05)。结论:腰骶段畸形行长节段固定矫形术可获得良好的矫形效果,但存在一定的术后冠状面失平衡风险,其原因可能与截骨不彻底、矫形策略及固定椎选择不当有关。     

青少年特发性脊柱侧凸的选择性胸椎融合治疗

目的　探讨青少年特发性脊柱侧凸选择性胸椎融合治疗的适应证。方法　回顾性分析12例行选择性胸椎融合患者术前、术后及随访时的X光像 ,对侧凸类型、侧凸Cobb角、顶椎旋转度、顶椎偏距、侧凸柔韧性、躯干偏移及胸腰段矢状面Cobb角进行测量和分析。患者 12例中男 2例 ,女10例 ,平均年龄 15 1(13～ 18)岁。侧凸均为KingⅡ型 ,其中PUMCⅡb1型 9例 ,Ⅱc3型 3例。所有病例均行选择性胸椎融合 ,平均随访 3 5 (1～ 10 5 )年。结果　手术前后胸弯冠状面Cobb角分别为5 4 0°、19 0° ,平均矫正率 6 2 7% ;腰弯冠状面Cobb角分别为 34 6°、12 5° ,自动矫正率为 6 4 7%。最后随访时 ,胸、腰弯的冠状面Cobb角分别为 18 8°、15 9°;腰弯冠状面Cobb角、顶椎偏距及顶椎旋转度与术后相比无显著变化。术后发生胸腰段后凸 1例 ,最终随访时未见进一步加重。无躯干失平衡现象发生。选择性胸椎融合较后路融合双弯平均减少 3 5个融合节段。结论　对腰弯柔韧性好且度数较小的KingⅡ (PUMCⅡb1和部分Ⅱc3)型特发性脊柱侧凸 ,可安全有效地行选择性胸椎融合     

前路半椎体切除截骨后路矫形固定治疗严重先天性脊柱侧凸

目的探讨分期前路半椎体切除截骨后路矫形手术治疗严重先天性脊柱侧凸的临床疗效。方法严重先天性脊柱侧凸14例,男4例,女10例;年龄8～13岁,平均11.2岁。其中形成缺陷2例,分节缺陷6例,混合型6例。半椎体位于T53例,T2、T8、T10、T11、L1、L4各1例。胸弯12例,胸腰弯2例。术前冠状面Cobb角63°～95°,平均72.1°。胸椎后凸减小或前凸8例,胸腰段后凸4例。一期采用前路半椎体切除、多节段椎体间楔形截骨及分节不全松解;二期采用后路椎弓根钉棒系统三维矫形固定。前后路手术均植骨,平均截骨5.5个节段。结果一期前路术后冠状面Cobb角48°～60°,平均51.5°;矫正率19.6%～37.8%,平均28.6%。二期术后冠状面Cobb角5°～45°,平均30.5°;矫正率52.6%～87.5%,平均62.5%。8例存在胸椎后凸减小或前凸的患者均恢复生理性后凸,4例胸腰段后凸患者3例达到矢状面矫正。全部病例随访8～30个月,平均12.1个月。无断钉、断棒及明显的矫正度丢失,植骨融合良好。发生并发症2例,椎弓根钉帽松动1例,T1神经根激惹1例。结论一期前路半椎体切除、多节段椎体间楔形截骨、分节不全松解,二期后路矫形固定及前后路植骨治疗先天性脊柱侧凸能够达到较满意的矫形效果,适合于8～12岁的青春期前患者。     

先天性多发性关节挛缩症合并脊柱侧凸的临床特征及疗效评价

目的 探讨先天性多发性关节挛缩症(arthrogryposis multiplex congenital,AMC)合并脊柱侧凸的临床特征和手术方式并评估疗效.方法 回顾性分析2001年11月至2006年8月在我院接受脊柱三维矫形手术治疗的AMC合并脊柱侧凸患者14例,男7例,女7例;年龄11～20岁,平均14.3岁.对侧凸类型进行分析并对其手术前后侧凸冠状面和矢状面Cobb角、骨盆倾斜角进行评价.结果 12例为长"C"型胸腰弯,5例合并先天性脊柱侧凸.14例患者主弯冠状面Cobb角术前平均79.1°,术后平均35.9°,平均矫正率为54.6%;10例合并胸椎前凸畸形者矢状位术前胸椎前凸Cobb角平均43.0°,术后胸椎后凸Cobb角平均16.4°;2例合并胸椎后凸畸形者矢状位术前胸椎后凸Cobb角平均91.5°,术后胸椎后凸Cobb角平均54.5°;3例术前骨盆倾斜角平均22.1°,术后平均13.3°.术后随访2.0～4.5年,平均29个月,末次随访时冠状面矫正丢失率平均6.8%.3例发生术中和术后并发症:1例后路矫形时发生大出血(4000m1);1例术后出现短暂性呼吸困难;1例二期后路内同定完成后出现完全性截瘫,术后3个月恢复正常.结论 AMC合并脊柱侧凸弯型以麻痹性神经肌源性长"C"型胸腰弯为主,可合并有先天性脊柱侧凸.脊柱三维矫形可以对AMC合并脊柱侧凸进行有效的矫正,但易发生并发症.     

接受心脏手术的Marfan综合征患者合并脊柱侧凸的特点

目的:探讨接受心脏手术治疗的Marfan综合征患者合并脊柱侧凸的患病率、侧凸程度、类型及特点。方法:回顾性总结138例进行心脏外科手术的Marfan综合征患者的X线资料,测量冠状面和矢状面Cobb角,并对数据进行统计分析。结果:58例(42.03%)患者合并脊柱侧凸,男38例,女20例,男女患病率比例为1.18∶1,其中≤10岁6例,11～20岁12例,21～30岁19例,31～40岁11例,41～50岁7例,51～60岁3例;平均冠状面Cobb角为26.8°±27.8°;胸弯36例,胸腰弯11例,腰弯2例,双弯6例,三弯3例;单弯中顶椎凸向右侧38例,凸向左侧11例;矢状面胸椎后凸平均为14.3°±13.2°,其中胸椎前凸5例,胸椎后凸不足40例,胸椎正常后凸12例,仅1例胸椎后凸45°;11例患者冠状面Cobb角>40°,平均年龄15.9岁。结论:在接受心脏手术的Marfan综合征患者中脊柱侧凸患病率为42.03%;脊柱侧凸类型多样,冠状位畸形以胸弯和胸腰弯多见,胸椎凸向右侧发生率较高,矢状位畸形以胸椎后凸不足为主;在青少年表现较为严重,需要严密的随访及手术矫形。     

后路一期半椎体切除治疗胸腰椎多发半椎体脊柱畸形

目的：观察后路一期半椎体切除、内固定植骨融合术治疗胸腰椎多发半椎体脊柱畸形的临床效果。方法2005年6月至2012年12月南华大学附属第一医院收治9例胸腰椎多发半椎体畸形患儿,其中3例胸腰椎有3个半椎体畸形、6例有2个半椎体畸形,共计21个半椎体;完全分节型14个、不完全分节型7个。均行后路一期半椎体切除、内固定植骨融合术,术前、术后和定期随访时拍摄站立位脊柱正侧位片,测量冠状面侧凸Cobb角及矢状面后凸Cobb角。结果全部患者获随访7～52个月（平均24.8个月）。手术时间210～450 min （平均326 min）,术中出血量1200～3800 mL（平均1950 mL）。冠状面侧凸Cobb角由术前的（47±10）°矫正至术后的（14±4）°,矢状面后凸Cobb角由术前的（28±4）°矫正至术后的（11±4）°,手术前后比较,差异有统计学意义（P＜0.05）。末次随访时冠状面和矢状面矫形丢失不明显。1例术中出现硬脊膜撕裂致术后脑脊液漏,延长伤口引流时间后痊愈;1例术后出现神经根性分布一侧下肢麻木、胀痛,随访3个月症状消失。术后6个月随访9例患者均获得植骨融合,无一例发生感染、内固定失败及假关节形成。结论对于胸腰椎多发半椎体脊柱畸形,后路一期半椎体切除、内固定植骨融合术可取得良好的临床效果。     

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.