青少年特发性脊柱侧凸患者结束支具治疗后侧凸进展的危险因素分析

目的研究青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者结束支具治疗后侧凸进展的危险因素,为AIS的科学、合理使用支具治疗提供理论依据。方法纳入2013-03-2016-03于我院支具治疗的164例青少年特发性脊柱侧凸患者,结束支具治疗后随访24个月,以侧凸Cobb进展≥5°诊断为支具治疗后侧凸进展,设为进展组,侧凸Cobb进展5°设为非进展组。调查两组患者初诊年龄、性别、初诊Cobb角等病历资料,通过Logistic回归分析探究AIS患者结束支具治疗后侧凸进展的独立危险因素。结果 AIS患者结束支具治疗后侧凸进展38例,进展率23.17%,平均侧凸Cobb角(6.84±0.87)°,未进展126例,平均侧凸Cobb角(3.77±0.65)°;两组初发Cobb角、顶椎旋转度、站高增长速度、女性初潮年龄、Risser征的差异有统计学意义(P0.05);Logistic回归分析证实:初发Cobb角≥35°、顶椎旋转度≥Ⅲ度、女性初潮年龄12岁、站高增长速度30 mm/年,均是AIS患者结束支具后侧凸进展的独立危险因素。结论 AIS患者结束支具治疗后侧凸进展发生率较高,初发Cobb角≥35°、顶椎旋转度≥Ⅲ度、站高增长速度30 mm/年、女性初潮年龄12岁均会增加侧凸进展风险。     

支具治疗后初始Cobb角进展速率对青少年特发性脊柱侧凸患者支具疗效的预测价值

目的 :比较行支具治疗的青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者的支具治疗后初始Cobb角进展速率(initial angle velocity,IAV)和初始矫正率与支具疗效的相关性,探讨IAV对AIS患者支具疗效的预测价值。方法:回顾性分析于我院门诊行正规支具治疗的女性AIS患者126例,其中胸主弯74例,胸腰弯52例。于患者每次随访拍摄的站立位全脊柱正位片上测量主弯的Cobb角和Risser征。另外记录患者每次随访时的实足年龄、月经状态及身高等资料。根据患者末次随访时Cobb角进展程度分为两组:进展组55例Cobb角进展≥6°;非进展组71例Cobb进展6°。IAV定义为患者支具治疗后第一次随访时的Cobb角进展速率,初始矫正率定义为支具治疗后第一次随访时的Cobb角矫正率。采用独立样本t检验比较两组之间的差异,逻辑回归分析不同支具疗效的预测因素。结果:本组所有患者平均初诊年龄12.4±1.6岁;月经年龄12.3±1.2岁;平均初诊身高154.4±9.7cm;初诊Risser征2.1±1.7;平均初诊Cobb角24.4°±6.1°。初诊至第一次随访平均时间间隔4.1±0.6个月;初诊至末次随访平均时间间隔35.9±13.7个月(24~60个月)。末次随访时平均Cobb角29.2°±8.4°。独立样本t检验示进展组和非进展组患者初诊年龄、月经年龄、初诊身高、初诊Risser征及初诊Cobb角均无显著差异(P0.05)。非进展组IAV显著小于进展组(-9.9°±13.8°/年VS 5.2°±12.5°/年,P0.001),而非进展组初始Cobb角矫正率显著大于进展组[(11.6±16.9)%VS(-5.3±16.4)%,P0.001]。逻辑回归分析示支具疗效与IAV(OR=8.451,P=0.004)呈显著相关,而与初始矫正率(OR=2.192,P=0.139)无显著相关。结论:支具治疗后初始Cobb角进展速率与AIS患者支具疗效呈显著相关,较高的支具治疗后初始Cobb角进展速率预示较差的支具治疗效果。     

性别对青少年特发性脊柱侧凸患者支具治疗效果的影响

目的:比较男、女性青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者支具治疗的效果,探讨性别因素对支具治疗效果的影响。方法:2003年7月~2009年7月在我院完成支具治疗的男性AIS患者19例(A组),初诊时平均年龄14.0±2.0岁,平均主弯Cobb角28.8°±5.7°,初始Boston支具治疗6例,Milwaukee支具治疗13例;随机抽取同时期完成支具治疗的女性AIS患者57例(B组),初诊时平均年龄13.0±1.4岁,平均主弯Cobb角29.4°±6.1°,初始Boston支具治疗17例,Milwaukee支具治疗40例。定义末次随访时Cobb角大于初诊6°或治疗期间建议行矫形手术者为侧凸进展。结果:两组初诊时Risser征(P=0.786)、Cobb角(P=0.790)、弯型分布(P=0.350)和应用支具类型分布(P=0.350)等无显著性差异。A组和B组平均支具治疗时长分别为2.1±0.7年和2.5±0.9年,平均依从性分别为84.4%±7.6%和87.1%±5.7%。A组患者中发生侧凸进展8例(42%),其中需手术治疗者6例(32%);B组中侧凸进展12例(21%),其中需手术治疗者10例(18%)。男性患者侧凸进展比例高于女性,但统计学差异不明显(P=0.071)。两组中,生长发育状态低下、侧凸Cobb角大及主胸弯型患者侧凸进展比例高。结论:支具治疗可有效控制多数AIS患者的侧凸进展,女性患者支具治疗效果可能好于男性患者。     

行支具治疗的特发性脊柱侧凸患儿生长高峰期Cobb角进展速率变化及其对支具疗效的影响

目的:评估行支具治疗的特发性脊柱侧凸(idiopathic scoliosis,IS)患儿青春期生长高峰参数及生长高峰时的脊柱侧凸Cobb角进展速率(angle velocity,AV)变化情况,评估正性和负性AV组之间支具疗效的差异及不同支具疗效组之间生长参数的差异。方法:选取初诊时Y三角软骨未闭、以3~6个月为周期随访至停止支具治疗或因侧凸进展而行手术治疗的女性IS患儿35例。随访时测量的指标包括实足年龄、Y三角软骨闭合状态、Risser征、身高、脊柱长度、主弯Cobb角和尺桡骨远端骨龄(digital radius and ulnar,DRU)分级。根据纵向数据判定身高和脊柱生长速率峰值(peak height growth velocity,PHGV;peak spinal growth velocity,PSGV)及相应年龄,分析AV在该阶段的变化情况及其对支具疗效的影响。支具治疗失败定义为主弯Cobb角进展≥5°或进展至超过40°需行手术治疗。结果:35例患儿初诊年龄为10.2±1.5岁(8~12.5岁),初诊Cobb角为26.5°±5.0°(20°~38°),20例主胸弯或胸腰双弯患儿接受Milwaukee支具治疗,15例胸腰弯及腰弯患儿接受Boston支具治疗。随访时间为5.1±2.1年(4.0~6.2年),末次随访年龄15.3±2.2岁(12~18岁),末次随访Cobb角为34.0°±12.6°(9°~59°)。支具治疗成功15例(42.9%);支具治疗失败20例(57.1%),其中转为手术16例(45.7%)。支具治疗失败组患儿PHGV年龄、PSGV年龄均较治疗成功组患儿更小(P0.05),而支具治疗失败组的末次随访Cobb角、胸弯百分率及PSGV时AV均高于成功组(P0.05),PHGV和PSGV的值、初诊Cobb角两组之间无统计学差异(P0.05)。PSGV时负性AV组19例(54.3%),正性AV组16例(45.7%),负性AV组的支具治疗失败率、手术率、PSGV时AV及末次随访Cobb角均显著低于正性AV组(P0.05)。结论:行支具治疗的IS患儿生长高峰期时AV变化与支具疗效显著相关。处于生长加速期的IS患儿,其支具治疗失败率较高,尤其是脊柱生长高峰发生时间较早的胸弯型患儿。生长高峰时负性AV预示着更好的远期支具治疗效果。     

青少年特发性脊柱侧凸支具治疗结束后近期矫正丢失及影响因素

目的:观察青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)支具治疗结束后短期内侧凸的矫正丢失情况,并探讨其影响因素。方法:选取2002年10月～2007年12月在我院完成规范化支具治疗后短期随访的AIS患者84例,其中男4例,女80例。初诊时年龄10～15岁,平均12.8岁;Risser征0～3级,平均1.6级;主弯Cobb角20°～43°,平均29.5°。胸腰双主弯36例,单胸弯22例,单胸腰弯或腰弯26例。所有患者在初诊、复查时均摄佩带支具前后站立位全脊柱正位X线片。分别测定不同时期侧凸Cobb角,记录侧凸类型、Risser征、患者的生理年龄及月经初潮时间,分析去除支具后侧凸的矫正丢失情况及影响因素。结果:AIS患者支具治疗后主弯Cobb角的平均矫正率为12.4%,其中14例(16.7%)患者在治疗期间出现脊柱侧凸进展,不同弯型脊柱侧凸的侧凸矫正率、进展率比较差异无显著性(P0.05)。支具治疗结束时主弯Cobb角10°～37°,平均25.5°,明显小于初诊时的29.5°(P0.05),停用支具后6～18个月主弯Cobb角为27.2°,与支具治疗结束时比较无显著性差异(P0.05)。停用支具后,有15例(17.6%)患者出现脊柱侧凸进展,不同弯型脊柱侧凸进展差异无统计学意义(P0.05);侧凸进展的患者在支具治疗时主弯Cobb角的平均矫正率为23.3%,明显高于未出现侧凸进展患者的10.6%,且差异具有统计学意义(P0.05)。停用支具时不同Cobb角组后期出现侧凸进展的概率无显著性差异(P0.05)。结论:支具治疗能够有效控制AIS患者侧凸的进展。在结束支具治疗后短期内随访侧凸矫正基本稳定,但仍有一小部分患者会出现侧凸进展,这种进展与弯型、侧凸的严重程度无关,可能与支具治疗期间侧凸的矫正率较大有关。     

结束支具治疗后青少年特发性脊柱侧凸的进展及影响因素分析

目的观察去除支具治疗后的青少年特发性脊柱侧凸患者后期侧凸的进展情况并分析其影响因素。方法自1975年8月至1994年4月共112例资料完整的、特发性脊柱侧凸完成支具治疗的、末次随访时间为去除支具后2年以上的、年龄为18岁以上的患者。分别测定不同时期侧凸的Cobb角,记录侧凸的类型、部位及去除支具时的生理年龄、Risser征和月经初潮时间,分析去除支具后侧凸的进展情况及影响因素。结果自确诊至末次随访时间平均为8.1年,去除支具后至末次随访时平均为3.8年。4.8%的继发性侧凸在去除支具后出现Cobb角5°以上的明显进展,显著低于原发性侧凸(16.3%,P<0.05)。原发性侧凸在RisserⅣ度或Ⅴ度时去除支具对Cobb角进展的影响无统计学意义。去除支具时年龄越大、月经初潮时间越长,侧凸Cobb角增大5°以上的概率越小。所应用的支具类型、去除支具时侧凸的严重程度(20°￣50°)与后期畸形进展之间差异无统计学意义(P>0.05)。结论去除支具后侧凸的进展主要受侧凸性质影响,与支具类型、去除支具时Risser征和侧凸严重程度无关。支除支具时年龄越大、月经初潮时间越长,后期出现Cobb角5°以上进展的可能性越小。     

Matrilin-1基因多态性与青少年特发性脊柱侧凸支具疗效的相关性

目的 探讨matrilin-1基因多态性与青少年特发性脊柱侧凸(AIS)患者支具治疗效果的相关性.方法 自2005年1月至2008年12月,对门诊行规范化支具治疗的AIS患者进行前瞻性研究.入选对象要求:女性患者;骨骼发育为未成熟状态(Risser征0～3级);月经初潮未至或来潮1.5年以内;标准站立位全脊柱X线片上侧凸Cobb角为20°～40°;排除了先天性和神经肌源性以及其他原因引起的侧凸;无已知的可影响骨塑型和钙代谢的病史和药物使用史;初诊前无支具治疗史;接受支具治疗(Boston支具或Milwaukee支具)期间每3个月复诊1次,随访时间超过2年.符合下述条件之一者,则予以剔除:最终随访不足2年;支具治疗过程中依从性(每日实际佩戴时间与建议佩戴时间的比值)较差(<75%);支具治疗期间未按照医嘱自行更换支具.根据患者侧凸类型选择相应的支具进行治疗.记录初次就诊及末次随访的原发弯的Cobb角.支具治疗失败的标准为原发弯增加>5°.选取matrilin-1基因启动子区域位点rs1149048进行PCR-RFLP基因分型.按支具疗效分为治疗失败和治疗成功两组,比较两组之间的初诊年龄、Risser征、侧凸类型、初诊Cobb角及基因型分布的差异并进行统计学分析.结果 共有77例AIS女孩入选并完成本研究.初诊时平均年龄为(13.0±1.5)年,平均主弯Cobb角为29.5°±7.8°.在平均(2.6±0.3)年随访后,平均主弯Cobb角为30.3°±11.9°.支具治疗失败总共19例(24.7%),支具治疗成功58例(75.3%).支具治疗失败组的初诊Cobb角较大(P>0.05).在不同的侧凸类型中,胸腰双主弯的支具治疗失败率最低(19.4%).基因型GG个体支具治疗失败率(66.7%)明显高于基因型为从或AG的个体.结论 通过早期规范化支具治疗,大部分脊柱侧凸进展可得到控制.初诊Cobb角较大及基因型GG的AIS患者支具疗效较差.     

女性青少年特发性脊柱侧凸支具治疗效果和影响因素评估

目的 评估女性青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者支具治疗效果及影响因素.方法 2003年7月至2009年7月,完成支具治疗或因侧凸进展而行手术治疗的女性AIS患者142例,初诊时平均年龄为(13.1±1.5)岁,平均主弯Cobb角29.6°±5.4°,平均Risser征为(2.0±1.5)级.定义侧凸畸形进展为末次随访Cobb角大于初诊6°以上或治疗期间建议行矫形手术(Cobb 角＞45°),其余为非进展.根据侧凸进展或需手术治疗的比率来评估支具治疗效果.运用卡方检验和Logistic回归分析探讨影响支具治疗效果的因素.结果 平均支具治疗时间为(2.5±1.0)年.按照侧凸进展的定义,进展组为27例(19%),非进展组115例(81%);手术组病例18例(13%),因支具治疗而避免手术病例124例(87%).卡方检验发现侧凸进展组和手术组中以初诊年龄10.0～12.9岁、月经初潮未至、Risser征0～1级、初诊Cobb角＞30°以及胸弯型居多.Logistic回归分析发现月经初潮未至(P=0.000)和胸弯型(P=0.012)是支具治疗后侧凸进展的独立预测因素,而初诊Cobb角＞30°(P=0.022)是支具治疗期间因侧凸进展而需手术治疗的另一独立预测因素.结论 支具治疗可有效控制多数AIS患者的侧凸进展,而生长发育状态、侧凸严重程度和侧凸类型是影响支具疗效的重要因素.

Abstract：

Objective To analyze the outcomes of bracing treatment for girls with adolescent idiopathic scoliosis (AIS), and to investigate the predictive factors of the protocol. Methods This study included 142 girls with AIS who finished standardized bracing treatment from July 2003 to July 2009. These patients had a mean age of 13.1±1.5 years, a mean main curve of 29.6°±5.4°, and a mean Risser grade of 2.0±1.5 before bracing treatment. Curve progression was defined that Cobb angle was greater than 6° compared to bracing initiation or was aggravated to more than 45° (indicative for surgery). The outcomes of bracing treatment were assessed based on the ratio of curves of progression or indicative for surgery. Chi-square and Logistic regression Analyses were performed to investigate the predictive factors of bracing treatment. Results The duration of bracing treatment averaged 2.5±1.0 years. Twenty-seven girls with curve progression (19%)and 115 girls (81%) with non-progression were found. Final curve which was greater than 45° was found in 18 girls (13%) who need a correction surgery, the remaining 124 girls (87%) had completed bracing treatment and avoided surgery. Chi-square analyses revealed that curve progression were more common in younger girls with lower Risser grade, with initial larger Cobb angle and with a main thoracic curve pattern.Logistic regression analyses found that premenarchal status and a main thoracic curve pattern were the independent risk factors of curve progression despite bracing. While initial Cobb angle which was greater than 30° was the additional independent risk factor of progression requiring surgery. Conclusion Bracing treatment could effectively prevent curve progression in most girls with AIS. The degree of growth maturity, the pattern and grade of curve are the influencing factor for bracing treatment.     

支具治疗女性青少年特发性脊柱侧凸畸形加重的危险因素分析

目的:观察支具治疗女性青少年特发性脊柱侧凸的畸形变化情况并分析侧凸畸形进展的危险因素。方法:对65例接受支具治疗的女性青少年特发性脊柱侧凸患者进行随访。在随访期间连续测量记录患者的Cobb角、侧凸类型、月经初潮与否、坐高、站高、Risser分级、顶椎旋转度等。分析初诊时和末次随访时侧凸变化情况,并从上述多项参数中筛选引起侧凸加重的危险因素。结果:65例获得随访,时间12～60个月,平均24.1个月。初诊年龄10～16岁,平均13.7岁。末次随访时17例(26.15%)患者侧凸进展超过5°,初诊时原发弯Cobb角>35°,顶椎旋转度≥Ⅲ度的患者,侧凸明显进展的百分率较高(P<0.05)。通过Logistic逐步回归分析,发现初诊时原发弯Cobb角>35°,顶椎旋转度≥Ⅲ度,年身高增长>30mm的患者,是侧凸进展到5°以上的危险因素。结论:初诊时原发弯Cobb角值,顶椎旋转度及身高增长速度是预测女性青少年特发性脊柱侧凸进展的重要因素,借助Risser分级预测侧凸进展并不可靠,初始原发弯Cobb角>35°、顶椎旋转度≥Ⅲ度、年身高增长>30mm的患者,侧凸进展的危险性较高。     

Cheneau支具佩戴依从性对青少年特发性脊柱侧凸患者生存质量及疗效的影响

目的:探讨Cheneau支具佩戴依从性与高侧凸进展风险青少年特发性脊柱侧凸(adolescent idiopathicscoliosis,AIS)患者侧凸进展的关系,比较不同依从性患者的健康相关生存质量.方法:2007年1月～2012年12月,在我院行Cheneau支具治疗的高侧凸进展风险AIS患者73例,初诊时平均年龄为12.8±1.2岁,平均主弯Cobb角31.4°±6.0°,平均Risser征为0.7±0.8级.所有患者每3～6个月定期复查,行临床及影像学检查,摄站立位脊柱全长正侧位X线片.在末次随访时每位患者填写健康相关生存质量问卷量表.侧凸进展定义为末次随访Cobb角大于初诊6°以上或治疗期间建议行矫形手术(Cobb角＞45°),其余为非进展.依从定义为患者每天坚持佩戴支具时间≥22h直至随访终止,否则视为不依从.随访结束后根据患者依从性不同将患者分为2组,应用独立样本t检验和卡方检验分析依从性对患者侧凸进展及健康相关生存质量的影响.结果:平均随访时间为1.8±0.8年.根据依从性定义,47例(64％)患者被纳入依从组,26例(36％)纳入不依从组.依从组患者末次随访时主弯Cobb角(28.9°±11.7°)明显小于不依从组(38.6°±11.6°),有统计学差异(P＜0.01).依从组侧凸进展率明显低于不依从组(OR 5.7,95％CI 1.9～16.8,P＜0.01).末次随访时不依从组自我形象/外观、精神健康、治疗满意度三个维度的得分均低于依从组(P＜0.01);不依从组患者欧洲五维健康量表得分亦明显低于依从组(P＜0.01).结论:良好的支具佩戴依从性可降低高侧凸进展风险AIS患者的侧凸进展率,提高患者健康相关生存质量.     

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.