胸腔镜下前路矫形治疗青少年特发性胸椎侧凸

目的探讨胸腔镜下前路矫形治疗青少年特发性胸椎侧凸的疗效。方法青少年特发性胸椎侧凸33例,男7例,女26例;年龄10～18岁,平均13.6岁。Lenke分型均为Ⅰ型,其中24例为ⅠA型,9例为ⅠB型。术前Cobb角:冠状面原发性胸弯平均57.4°(43°～68°),代偿性腰弯平均32.0°(20°～47°);27例存在胸椎后凸不足畸形,胸椎后凸平均6.3°(0°～18°)。手术方法为前路胸腔镜下切除椎间盘进行松解,应用CDHorizonEclipse矫形内固定,同时在椎间隙植骨。随访期间测量冠状面Cobb角及矢状面胸椎后凸成角,了解冠状面和矢状面畸形矫正情况。结果固定节段包括T4～T12,平均7.4个。平均手术时间为3h48min,平均术中出血量为308ml,平均住院时间4.4d。全部病例随访6～36个月,平均20.6个月。末次随访时原发性胸弯平均矫正60.2%,代偿性腰弯自然矫正平均50.3%,胸椎后凸平均矫正20.4°。1例出现假关节形成及内固定折断,2例出现胸壁麻木。结论胸腔镜下前路矫形治疗胸椎侧凸具有创伤小、术后恢复快等优点,能达到与开胸前路矫形术同样的矫形效果。     

女性青少年特发性脊柱侧凸患者停止支具治疗后的侧凸进展及其相关因素

目的 :分析发育成熟的女性青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患儿在停止支具治疗后长期随访中的侧凸进展情况,并探讨其相关因素。方法:回顾性分析于我院门诊就诊符合SRS(scoliosis research society)支具治疗标准的女性AIS患儿130例,初诊年龄11.8±1.4岁(10~14岁)。所有患儿均随访至支具治疗结束后至少2年,且至少具有佩戴支具后初次随访、停止支具治疗时、停止支具治疗后6个月、1年、2年及末次随访时的资料。在每次随访时的全脊柱正位X线片上测量主弯侧凸Cobb角,并评估侧凸进展超过5°的患儿及比例、侧凸进展度数和进展速率。末次随访时侧凸进展超过5°定义为侧凸进展,采用独立样本t检验比较侧凸进展组和非进展组患儿的初诊年龄、月经初潮年龄、初诊Cobb角、初始矫正率、停止支具治疗年龄。结果:与停止支具治疗时相比,停止支具治疗后6个月、1年、2年及末次随访时的侧凸进展超过5°的患儿分别为33例(25.4%)、42例(32.3%)、61例(46.9%)和63例(48.5%);侧凸进展度数分别为2.0°±4.4°、3.2°±5.0°、4.9°±5.5°和5.1°±6.9°;侧凸进展速率分别为0.33°±0.71°/月、0.20°±0.41°/月、0.14°±0.29°/月和0.01°±0.19°/月。停止支具治疗后侧凸非进展组和进展组患儿的初诊年龄、月经初潮年龄、初诊Cobb角、初始矫正率、停止支具治疗时年龄等无显著性差异(P0.05),而停止支具治疗时的Cobb角有统计学差异(P0.05)。结论:行支具治疗的AIS患儿停止支具治疗后仍有较高的侧凸进展风险,停止支具治疗后的6个月内为侧凸进展高风险和高速率期;停止支具治疗时的侧凸Cobb角越大发生侧凸进展的风险越高。     

青少年特发性脊柱侧凸的支具治疗

目的探讨青少年特发性脊柱侧凸支具治疗的适应证,并评价其临床疗效。方法77例骨骼发育未成熟的青少年特发性脊柱侧凸患者接受Milwaukee支具或Boston支具矫正,男15例,女62例;年龄10～15岁,平均12.7岁。胸腰双主弯26例、单胸弯37例、单胸腰弯或腰弯14例。原发弯Cobb角22°～62°,平均35.9°;20°～35°者37例,>35°者40例。Risser征0度38例、Ⅰ度19例、Ⅱ度13例、Ⅲ度7例。每3～6个月定期复查,复查时均摄佩带支具前、后的站立位全脊柱正位X线片,测量初次就诊及末次随访时的Cobb角、顶椎旋转度及Risser征。结果全部病例随访24～60个月,平均30个月。29.9%的病例出现脊柱侧凸进展,不同类型脊柱侧凸中胸腰双主弯进展率最低,但与其他类型比较差异无显著性。Risser征越小,初诊支具矫正率越大、侧凸进展率越高,且Risser征Ⅰ度组(包括0度)与Ⅱ度组之间、Ⅰ度组与Ⅲ度组之间初诊支具矫正率的差异有显著性(P<0.05)。原发弯Cobb角20°～35°组的初诊支具矫正率大于Cobb角>35°组(P<0.05);而侧凸进展率低于Cobb角>35°组,但差异无显著性。21例因出现侧凸进展而采用手术矫形,支具治疗使其中13例的手术时间推迟了12～20个月。结论Risser征可作为预测青少年特发性脊柱侧凸支具矫正成功率的一个指标。不同类型脊柱侧凸中胸     

先天性半椎体切除术后新发侧凸畸形的临床分析

目的:分析后路半椎体切除、短节段融合术后新发侧凸畸形(emerging scoliosis,ES)的临床特征以及处理策略。方法:2008年1月~2017年1月,168例单发半椎体畸形的患者在我科接受单纯后路半椎体切除、短节段椎弓根螺钉内固定植骨融合术治疗,其中12例发生ES。ES诊断标准:(1)新发弯Cobb角较术前同节段Cobb角进展≥20°;(2)同时新发弯主弯顶椎距离融合节段端椎的节段≥2(近端融合椎以上或远端融合椎以下);(3)排除半椎体切除不完全、融合内固定失败等因素。男4例,女8例;年龄11.8±3.2岁(5~15岁,其中10岁以下2例,10~15岁10例),融合节段数为2.7±1.0节(2~5节),随访34.0±10.0个月(18~50个月)。收集并测量患者术前、术后站立位全脊柱正侧位X线片等影像资料,对比分析患者主弯Cobb角、代偿弯Cobb角、新发侧凸Cobb角、节段后凸角度、术后融合交界区后凸角度等指标。结果:12例ES患者术前半椎体所在节段为胸腰段8例,胸段4例。经初次手术,患者半椎体节段侧凸Cobb角由术前36.1°±14.4°(21.8°~69.0°)显著减少至末次随访时的8.9°±8.5°(0°~19.5°)(P=0.000),平均矫正率为75.3%;节段后凸角从术前25.9°±12.8°(15.5°~40.2°)显著改善至末次随访时的9.5°±4.3°(4.0°~14.7°)(P=0.014)。术后ES出现时间:术后3个月5例,6个月7例。7例患者术后ES的节段与术前代偿弯节段一致。5例患者接受观察,其中1例ES进展接受翻修手术治疗,其他4例患者平均随访至术后25个月(18~36个月),ES角度无明显进展(平均25°→32°);7例患者接受支具治疗,其中4例支具治疗效果满意,支具治疗后平均随访36个月(24~42个月),ES角度有所改善(平均34°→23°)。4例患者在观察或支具治疗失败后(ES角度45°且发展为结构弯),接受翻修手术治疗,翻修术后随访平均22.5个月(12~36个月),ES角度由平均52°(45°~64.2°)矫正至末次随访时平均13°(0°~25°),且均未出现其他继发畸形。结论:后路半椎体切除短节段融合术后ES的发生率约为7%,胸腰段半椎体(T11~L1)及初次手术患者年龄偏大(青春期)为其可能风险因素,其发生和进展较为迅速(3~6个月内),针对该并发症的治疗策略应采用"观察—支具—手术"的阶梯性治疗策略。     

胸腔镜下前路松解后路混合钉钩内固定治疗严重特发性胸椎侧凸

目的 比较胸腔镜下前路松解后路混合钉钩内固定融合术( APSF)与单一后路全椎弓根螺钉内固定(PSSF)治疗严重特发性胸椎侧凸的疗效.方法 回顾性分析2001年11月至2008年12月采用APSF治疗的特发性胸椎侧凸患者资料,选择其中胸椎Cobb角≥70°、柔韧性≤50％的患者作为研究对象(APSF组),并选择同期胸椎侧凸严重程度和柔韧性匹配的行PSSF治疗的患者作为对照(PSSF组).全部患者术后均随访≥24个月.APSF组有患者18例,PSSF组27例,两组患者平均年龄分别为(15.9±2.1)岁和(15.8±2.9)岁.在两组患者术前、术后及末次随访时检查的站立位全脊柱正侧位X线片上测量胸主弯侧凸Cobb角、胸椎后凸(T5～T12)Cobb角,对两组的影像学参数、固定节段、植入物密度及并发症情况进行比较.结果 APSF组和PSSF组术前胸主弯侧凸Cobb角平均分别为87°±12°和79°±8°,平均固定节段(12.7±1.2)个和(12.8±1.4)个,植入物密度分别为48％±5％和61％±6％,术后平均矫正率为58％±13％和59％±8％;两组患者平均随访(4.5±0.6)年和(2.8±0.7)年,末次随访时矫正丢失分别为4.4°和1.9°.APSF组植入物密度较PSSF组低(t=6.123,P＜0.001),两组患者术前、术后和末次随访时胸椎侧凸及后凸差异均无统计学意义(P＞0.05).结论 对于严重僵硬型特发性胸椎侧凸,通过增加植入物密度,PSSF可获得与APSF一样的疗效.但对于有高度发生矫正丢失、内固定并发症或假关节风险的患者,仍然建议采用APSF方案.     

一期前后联合入路截骨矫形治疗先天性颈椎侧凸

目的:探讨一期前后路联合入路半椎体切除、环形截骨矫形术治疗先天性颈椎侧凸畸形的可行性、安全性,评价其初步疗效。方法:2009年12月~2013年11月应用一期前后路联合入路半椎骨切除、环形截骨矫形术治疗13例颈椎半椎体畸形导致的先天性颈椎侧凸患者,回顾性分析患者的资料,观察临床效果。统计神经根、脊髓、椎动脉、硬膜囊损伤等严重并发症。对比分析术前和术后颈椎CT冠状面重建图像上颈椎侧凸结构曲线和颈椎或者上胸椎的代偿曲线(Cobb角)。结果:13例患者中男8例,女5例。年龄5~15岁(9.2±3.4岁)。11例接受一期前路截骨、后路截骨矫形内固定融合、前路内固定融合术;2例接受一期前路截骨、后路截骨矫形内固定融合术,术后Halo-vest支具固定3个月。手术时间210~520min(324±92min),出血量150~1000ml(585±319ml)。5例术后出现凸侧神经根刺激症状,4例在术后6个月时完全缓解,1例在术后24个月时肱三头肌肌力仍为3级。随访24~60个月(30.0±12.4个月),颈椎侧凸结构曲线Cobb角由术前9°~45°(28.3°±11.0°)矫正至0°~25°(6.9°±7.8°),矫正率为44.4%~100%[(78±24)%];颈椎或者上胸椎的代偿曲线Cobb角由术前0°~25°,(21.8°±5.8°)矫正至3°~23°(5.5°±4.3°),矫正率为8%~75%[(37±33)%]。末次随访时,患者头颈肩部外观显著改善。结论:采用一期前后路联合入路半椎体切除、环形截骨矫形术治疗先天性颈椎侧凸具有较好的可行性和安全性,初步临床及影像学效果满意。     

经椎弓根椎体间截骨联合V形截骨术矫正强直性脊柱炎合并重度胸腰椎后凸畸形

目的 评估后路联合经椎弓根椎体间截骨手术(PSO)和椎板关节突V形截骨术矫正强直性脊柱炎(AS)合并重度胸腰椎后凸畸形的临床疗效.方法 2004年8月至2007年6月,共收治AS合并重度胸腰椎后凸畸形患者8例,均为男性,年龄28～46岁,平均32岁;平均胸椎后凸角度(T1～T12)96°(80°～112°),腰椎前凸角度(L1～S1)平均10°(5°～15°),平均颏眉角47°(40°～58°),平均注视角43°(32°～50°).8例患者均在L3椎体行PSO术并在胸腰段(T12～L1,L1-2)之间进行椎板关节突V形截骨.术后综合评估影像学、临床疗效以及并发症的情况.结果 8例患者平均手术时间(298.1±20.7)min,术中失血量(1588.8±171.6)ml.8例患者均获随访,随访时间为(11.5±7.7)个月.术后平均胸椎Cobb角76.1°±9.6°,矫正20.3°±1.1°;术后平均腰椎前凸角48.4°±4.7°,矫正38.4°±4.7°.术后平均颏眉角16.5°±4.6°,注视角73.0°±5.2°.矢状面平衡矫正(12.3±1.6)cm.无血管、神经损伤、应力性骨折等重大并发症发生,术后未发生冠状面的失代偿.结论 后路联合单节段PSO联合双节段楔形截骨术矫正As合并重度后凸畸形效果安全可靠,可明显改善患者视野范围.     

两种矫形方法治疗成人特发性脊柱侧凸的疗效比较

目的:比较单纯后路矫形术和一期前路松解、Halo-股骨髁上牵引加二期后路矫形术治疗成人特发性脊柱侧凸的疗效。方法:选取我院脊柱外科2003年1月～2007年12月收治的有完整影像学资料、Cobb角65°～90°的成人特发性脊柱侧凸患者30例,年龄20～30岁,平均23.4岁。均为初次手术,术前无神经损害。根据不同手术方法分为两组,行单纯后路矫形术的14例患者为A组,行一期前路松解、Halo-股骨髁上牵引及二期后路矫形术的16例患者为B组。两组患者术前侧凸Cobb角、胸椎后凸角、年龄、性别比、侧凸类型相匹配。随访时间为12～72个月,平均40个月。比较两组患者手术时间、出血量、住院时间、并发症情况、侧凸矫正率和冠状面平衡情况。结果:平均手术时间和平均住院时间A组分别为6.7±1.2h和24±18d,B组分别为9.9±1.4h和41±10d,B组均显著长于A组(P<0.05)。所有病例术后均无瘫痪、呼吸衰竭、死亡等并发症发生。术后侧凸矫正率A组为(51.3±11.8)%,B组为(64.5±11.6)%,B组显著大于A组(P<0.05);胸椎后凸角、C7中垂线与骶骨中线的距离A组为20.6°±8.4°、1.32±0.65cm,B组为20.4°±6.7°、1.30±0.70cm,两组比较均无显著性差异(P>0.05)。末次随访时A组侧凸矫正丢失率为(3.5±2.4)%,B组为(2.8±1.5)%,两组无显著性差异(P>0.05)。结论:两种治疗方案治疗中度成人特发性脊柱侧凸均可获得较好的畸形矫正,一期前路松解、Halo-双侧股骨髁上牵引可以增加侧凸Cobb角矫正率,但是存在显著增加手术时间和住院时间等不足。     

前路与后路手术治疗上胸椎结核的临床疗效及并发症对比

目的:对比前路与后路手术治疗上胸椎结核(T1～T5)的临床疗效和并发症。方法:回顾性分析我科2005年4月～2014年4月采用手术治疗的29例上胸椎结核患者的临床资料,其中13例行一期前路病灶清除、植骨融合内固定术(前路组),男7例,女6例,年龄22～70岁(46.3±15.0岁);16例行一期后路病灶清除、植骨融合内固定术(后路组),男7例,女9例,年龄26～72岁(52.6±13.0岁)。术后均给予12～18个月抗结核药物治疗,随访2年以上,比较两组手术时间、出血量、住院时间及围手术期并发症,分析两组在神经功能改善、胸背痛评分、植骨融合时间、后凸畸形矫正及复发率方面的差异。结果:两组均顺利完成手术,前路组和后路组手术时间、术中出血量、住院时间分别为239.1±52.9min和228.0±26.8min、588.5±196.0ml和537.5±208.6ml、23.2±3.1d和16.8±3.1d,其中前路组住院时间显著性大于后路组(P0.05)。前路组发生8例次并发症(2例胸腔积液、1例翼状肩、1例气胸、1例肺不张、1例肋间神经痛、1例髂骨供区疼痛、1例双肺细菌性感染伴顽固性低钠血症),后路组发生4例次并发症(2例脑脊液漏、1例切口延迟愈合、1例术后神经症状一过性加重),前路组并发症发生率(3/18,61.54%)大于后路组(4/16,25%)(P0.05)。随访40～87个月(62.1±13.0个月),两组患者均获得临床治愈,无结核复发病例。前路组后凸Cobb角术前39.2°±9.4°,术后19.4°±4.7°,末次随访时22.5°±7.4°,矫正丢失3.1°±2.3°;后路组后凸Cobb角术前40.6°±7.3°,术后18.5°±3.5°,末次随访时21.2°±4.4°,矫正丢失2.7°±1.6°,两组间比较差异无统计学意义(P0.05)。前路组植骨融合时间(6.2±1.6个月)小于后路组(8.4±1.5个月),差异有统计学意义(P0.05)。前路组和后路组末次随访时的神经功能改善率及胸背痛VAS评分分别为100%和93.75%、2.16±0.75和2.01±0.68,两组间比较差异无统计学意义(P0.05)。结论:前后手术入路均可用于上胸椎结核的手术治疗,前路手术植骨融合早于后路手术,但前路手术围手术期并发症发生率高于后路手术。     

术中CT在后路全椎弓根螺钉治疗重度脊柱侧凸中的初步应用

目的:探讨术中CT在重度脊柱侧凸患者后路全椎弓根螺钉手术中的应用价值和临床疗效.方法:回顾性分析了2009年6月至201 1年6月行全椎弓根螺钉后路治疗的32例重度脊柱侧凸患者,其中男12例,女20例;年龄10～38岁,平均16.8岁;其中19例合并后凸.在术中椎弓根钉置钉完成后应用术中CT扫描多平面重建图像评估螺钉位置并分级,计算在上胸椎(T1-T4),中胸椎(T5-T8),下胸椎(T9-T12)和腰椎的螺钉评级结果及螺钉数目(比率),评估为2级和3级的螺钉为误置螺钉.计算术中应用CT次数.测量患者手术前后冠状面Cobb角及合并后凸病例手术前后矢状面后凸Cobb角,计算侧凸及后凸矫正率.结果:32例患者共置入胸腰椎螺钉686枚,其中胸椎螺钉544枚,腰椎螺钉142枚,其中14例患者行截骨手术.经术中CT评估分级,在上胸椎、中胸椎、下胸椎和腰椎的误置螺钉率分别是5.6％,11.1％,6.7％和4.3％,在胸腰椎总计是7.3％,误置螺钉在术中进行了修正.术中平均应用CT 2.6次(2～4次).术前侧凸Cobb角平均95°(78°～123°),术后侧凸Cobb角平均为34°(19°～53°),矫正率为64％;合并后凸病例术前后凸Cobb角69°(46°～82°),术后后凸Cobb角平均为32°(22°～45°),矫正率为54％.术后有4例患者脑脊液漏,未发现神经血管损伤病例及手术伤口感染病例.所有病例获得随访,时间12～26个月,平均18个月.未发现断钉、断棒、假关节形成等并发症发生.结论:在重度脊柱侧凸全椎弓根螺钉后路手术中应用术中CT可及时发现误置螺钉并进行修正,避免了因螺钉误置导致的二次手术,保障了手术安全,手术效果良好.     

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.