首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
目的比较青少年特发性脊柱侧凸King、Lenke和PuMC(协和)分型系统的可信度和可重复性,探讨PUMC(协和)分型的临床应用价值。方法随机选取2002年1月至2004年12月手术治疗的100例青少年特发性脊柱侧凸病例,男22例,女78例;年龄1肌18岁,平均14.9岁。主弯Cobb角40°-75°,平均52°每例患者均有完整的术前X线片资料,包括术前站立位全脊柱正侧位及仰卧位左右Bending片和骨盆X线片,X线片均不进行预先测量。由4名有分型经验的脊柱外科医生分别进行脊柱侧凸的King、Lenke和PUMC(协和)分型,2周后再次进行分型,收集结果后对分型的可信度和可重复性进行分析。计算Kappa检验的一致性。结果King、Lenke、PUMC(协和)分型的可信度平均为81.2%(Kappa值=0.773)、60.5%(Kappa值=0。560)、8413%(Kappa值=0.819),可重复性平均为91.5%(Kappa值=0.897)、81.8%(Kappa值=0.796)、92%(Kappa值=0.907)。结论PUMC(协和)分型包括了脊柱侧凸在三平面内的畸形特点,分型全面,易于掌握,而且具有很好的可信度和可重复性,适合脊柱侧凸的三维矫形。  相似文献   

2.
目的:探讨特发性脊柱侧凸PUMC(协和)分型系统的一致性,并对影响分型一致性的因素进行分析.方法:随机选取南京鼓楼医院2004年~2006年治疗的80例特发性脊柱侧凸患者,其中男性15例,女性65例,平均年龄14.6岁(10~18岁),均有完整的术前站立位正侧位X线片及仰卧位左右Bending片共四张.由4名脊柱外科专科医生分别根据PUMC(协和)分型标准进行分型,2周后此4位医生分别对这些患者的X线片再次进行分型,收集分型结果分别作可信度和可重复性分析,计算Kappa值检验一致性并对影响分型一致性的因素进行统计分析,结果:80例患者均可用PUMC分型,分型可信度平均Kappa值为0.801,可重复性Kappa值为0.878.PUMC分型不一致中包括上胸弯的界定18次;胸弯明显时,代偿性与结构性腰弯的界定15次;腰弯明显时,代偿性与结构性胸弯的界定18次;单弯顶点的判断20次;测量角度的差异18次.结论:PUMC(协和)分型学习曲线相对较短,易于掌握且具有良好的可信度和可重复性.  相似文献   

3.
【摘要】 目的:探讨脊柱侧凸胸椎椎弓根形态学分型系统在临床应用中的可信度与可重复性。方法:1998年1月~2009年1月手术治疗脊柱侧凸患者60例,术前均行胸椎CT扫描、椎弓根轴位薄层重建。根据椎弓根松质骨管腔的形态特征将脊柱侧凸胸椎椎弓根分为正常型、狭窄型、峡部硬化型、完全硬化型(包括凹陷硬化和平直硬化两个亚型)和缺如型。应用64排CT多层重建技术,测量、分析60例常见类型脊柱侧凸患者1440个胸椎椎弓根CT轴位扫描结果,由3位不了解本研究目的的脊柱外科高年资住院医师,在同一时间分别对1440个胸椎椎弓根CT轴位扫描结果进行分型。间隔1个月后,再次由这3位住院医师对这1440个椎弓根进行分型。应用Stata 10.0软件,运用多类别多评估者的Kappa分析方法进行统计学分析,评价观察者间的可信度及观察者内的可重复性。结果:3位医师之间首次分型结果相同的百分比分别为88%、84%、92%,可信度的Kappa系数分别为0.7647、0.6590、0.8292;同一医师前后两次分型结果相同的百分比分别为95%、97%、96%,可重复性的Kappa系数分别为0.9227、0.9513、0.9117。结论:脊柱侧凸胸椎椎弓根形态学分型系统具有中、高度的可信度和极好的可重复性。  相似文献   

4.
【摘要】 目的:介绍脊柱后路经椎间隙截骨术(trans-intervertebral space osteotomy,TIO)的技术理念、临床分型和应用策略。方法:根据TIO技术特点、手术操作过程中截骨切除范围所涉及的解剖结构,将其分为3大类型及2种扩大(+)型:围绕椎间盘及关节突关节为Ⅰ型,扩大至楔形切除椎间隙一侧终板为Ⅱ型(头尾双侧终板则为Ⅱ+型)。扩大至楔形切除椎间隙一侧椎弓根为Ⅲ型(双侧椎弓根则为Ⅲ+型);收集2003年1月~2012年12月接受后路经椎间隙截骨术治疗的30例胸腰椎侧后凸畸形患者的临床资料,其中男12例,女18例,年龄29~69岁(51.4±10.4岁)。由5位脊柱外科医师先后对患者的临床资料进行独立评估与分型(间隔2周),进行Kappa一致性检验以分析其可信度及可重复性。结果:30例患者中行Ⅰ型TIO 15例,Ⅱ型TIO 6例,Ⅱ+型TIO 3例,Ⅲ型TIO 4例,Ⅲ+型TIO 2例。观察者间一致性的Kappa系数0.806~0.953;观察者内一致性的Kappa系数为0.837~0.953,可信度及可重复性满意。结论:经椎间隙截骨临床分型实用可靠,可作为理论基础用于比较不同研究中经椎间隙截骨技术的手术效果,有利于指导脊柱侧后凸畸形的截骨矫形治疗。  相似文献   

5.
目的探讨胸腰椎骨折的Denis分型和胸腰椎损伤分类及严重程度评分(TLICS)分型系统在不同专业医师中应用的可信度和可重复性。方法分别由不同专科医师采用2种分型方法对85例胸腰椎骨折进行分类,间隔2个月后再次分型。分析2种分型的观察者间可信度和观察者内可重复性。结果按观察者间可信度,Denis分型的Kappa值在0.632~0.735,平均为0.661(基本可信)。TUCS分型具体分值的Kappa值在0.217~0.316,平均为0.273(轻中度可信)。TUCS的推荐治疗分类Kappa值在0.641~0.764,平均为0.704(基本可信)。按观察者内可重复性,Denis分型Kappa值在0.375—0.580,平均为0.459(中度可信)。TLICS分型具体分值的Kappa值在0.319~0.478,平均为0.380(轻中度可信)。TLICS的推荐治疗分类Kappa值在0.617~0.785,平均为0.724(基本可信)。结论胸腰椎骨折的Denis分型在各个专业医师中应用的可信度较好,仍有一定的临床价值。TLICS评分的推荐治疗分型在各个专业医师中的可信度与可重复性均更高,更有利于相互交流及指导治疗。  相似文献   

6.
青少年特发性脊柱侧凸的分型及其对制定治疗策略的意义   总被引:1,自引:0,他引:1  
Qiu Y 《中华外科杂志》2007,45(8):510-512
青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)手术策略的制定是一项系统工程,术前评估以及分型对于正确制定手术策略很重要。理想分型应具备以下要素:(1)几乎包含所有的侧凸类型;(2)对脊柱侧凸畸形进行包括矢状面和轴状面的三维评估;(3)有良好的可信度和可重复性,易用、易记;(4)最终提出每一种分型的手术策略。  相似文献   

7.
目的 比较脊柱侧凸Lenke分型和协和(PUMC)分型系统一致性差异对手术融合范围的影响.方法 随机选取青少年特发性脊柱侧凸62例,5名脊柱外科医生根据术前站立正侧位、仰卧位左右弯曲X线片进行分型.3周后,将病例顺序打乱,重复相同程序分型,每个病例共计10人次分型.根据5名医生的分型结果,分别探讨两种分型产生的一致性差异对手术融合范围选择的影响.结果 Lenke分型系统弯曲类型参数及PUMC分型的一致性均很好.Lenke分型弯曲类型参数10人次分型结果24例有分歧,PUMC分型10人次分型结果17例有分歧,差异无统计学意义.Lenke弯曲类型分歧病例中仅2例不影响融合范围,PUMC分歧病例中有7例不影响融合范围,差异有统计学意义.24例Lenke弯曲类型分歧病例用PUMC分型,有14例一致;17例PUMC分歧病例用Lenke弯曲类型分型,7例一致,但做一致性检验表明两种分型一致性好.24例Lenke弯曲类型分歧病例用PUMC分型后有19例不影响融合范围,17例PUMC分歧病例用Lenke弯曲类型分型后只有9例不影响融合范围,差异无统计学意义.结论 Lenke分型中决定手术融合范围的是弯曲类型参数,其与PUMC分型的可信度和可重复性均很好.但PUMC分型较简单实用,较少引起分歧,即使引起分歧,也有近半数的病例并不影响手术融合范围的选择.  相似文献   

8.
目的:评价新型胸腰椎骨折损伤AO分型系统的可信度和可重复性,探讨影响分型一致性的主要原因。方法:选取5名医师,根据术前正侧位X线片、CT、MRI影像,用新型AO分型系统独立对收治的70例胸腰椎骨折损伤患者进行分型。对同一例患者,5名医师在一次分型中只要有1名医师分型不同即认定为不一致。6周后,打乱资料顺序再次分型。全部资料均不含与分型有关的任何标记,应用加权Cohen′s Kappa系数(unweighted Cohen Kappa coefficients)评价观察者间可信度和观察者内可重复性。结果:新型AO分型系统的可信度Kappa系数为0.602,可重复性平均Kappa系数为0.782。在3大骨折类型中,压缩型(A型)和分离移位型(C型)损伤的判定具有中、高度的可信度和极好的可重复性,可信度Kappa系数分别为0.604、0.662,可重复性平均Kappa系数分别为0.787、0.761;牵张型损伤(B型)判定的一致性相对较差,可信度Kappa系数为0.362,可重复性平均Kappa系数为0.657。损伤各亚型整体一致性,可信度Kappa系数为0.526,可重复性平均Kappa系数为0.701;其中B2型一致性最差,可信度Kappa系数为0.214,可重复性平均Kappa系数为0.633;其次为A4型,可信度Kappa系数为0.322,可重复性平均Kappa系数为0.685。结论:新型胸腰椎骨折损伤AO分型系统具有中、高度的一致性和极好的可重复性,但对A4和B2型骨折判定的可信度较差。  相似文献   

9.
【摘要】 目的:评估GAP(global alignment and proportion)评分的可信度和可重复性,并探究其在成人脊柱畸形(adult spinal deformity,ASD)矫形术后力学并发症预测中的可靠性。方法:回顾性分析2014年12月~2016年12月在我院行脊柱后路矫形内固定术且随访超过2年的ASD患者98例,其中男性31例,女性67例,年龄38.8±8.6(20~71)岁,随访时间34.4±9.3个月。其中退变性脊柱侧后凸29例、先天性脊柱侧后凸28例、特发性脊柱侧凸19例、创伤后脊柱后凸9例、神经源性脊柱侧凸9例、休门氏病后凸畸形2例,综合征型脊柱侧凸2例(马凡综合征和类马凡综合征各1例)。通过患者术后全脊柱侧位X线片测量骨盆入射角(pelvic incidence,PI)、骶骨倾斜角(sacral slope,SS)、腰椎前凸角(lumbar lordosis,LL)、下腰椎前凸角(lower lumbar lordosis,LLL)和躯干整体倾斜(global tilt,GT)等影像学参数,并计算得出GAP评分,比较GAP评分的观察者间可信度和观察者内可重复性。根据GAP评分结果将患者分为3组:协调组(GAP评分0~2分);中等不协调组(GAP评分3~6分);严重不协调组(GAP评分7~13分),记录所有患者随访中出现的力学并发症,包括内固定失败、近端交界性后凸/失败(proximal junctional kyphosis/failure,PJK/PJF)、远端交界性后凸/失败(distal junctional kyphosis/failure,DJK/DJF),比较各组间力学并发症的发生率。收集患者术前及末次随访时疼痛视觉模拟评分(visual analogue scale,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI)问卷表和健康调查简表(the MOS item short form health survey,SF-36)评估结果,比较三组间生活质量评分。结果:3名观察者共进行了588次(98×3×2)次评分,纳入协调组共192(32.7%)次、中等不协调组共250(42.5%)次、严重不协调组共146(24.8%)次。观察者间GAP评分可信度Kappa值为0.765(基本可信),观察者内可重复性Kappa值为0.822(完全可信)。随访中发现力学并发症15例,包括内固定断裂5例(8.2%)、PJK 9例(9.2%)、螺钉松动1例(1.0%)。协调组、中等不协调组和严重不协调组并发症发生率分别为9.1%(3/33)、14.6%(6/41)和25.0%(6/24),三组之间差异无统计学意义(χ2=2.74,P=0.254)。三组患者术前生活质量评分未见明显差异(ODI:P=0.167;VAS:P=0.668;SF-36生理功能评分:P=0.896;SF-36心理功能评分:P=0.211)。末次随访时发现ODI(P=0.038)和SF-36生理功能评分(P=0.020)在三组间存在差异,而VAS(P=0.729)和SF-36心理功能评分(P=0.277)无组间差异。结论:GAP评分具有良好的观察者内和观察者间一致性,但评分结果与术后力学并发症发生风险无明显相关性。  相似文献   

10.
特发性脊柱侧凸King、Lenke和PUMC临床分型的应用比较   总被引:3,自引:1,他引:2  
目的比较特发性脊柱侧凸King、Lenke和PUMC分型的全面性及其对手术的指导价值。方法回顾性分析在巴塞罗那SantJoanDeDéu医院接受手术治疗的特发性脊柱侧凸患者145例的临床及影像学资料。所有病例均进行King、Lenke和PUMC分型,比较手术原则与三种分型方法的符合率及术后失代偿的发生情况。结果King分型能对全部病例中的122例进行分型,有23例无法应用King分型;而Lenke分型和PUMC分型均能对全部病例进行分型。145例患者中,手术原则符合King分型者99例(68.3%),符合Lenke分型者120例(82.8%),符合PUMC分型者107例(73.8%)。95例患者随访3~96个月,平均29.6个月。其中手术原则符合King分型、Lenke分型和PUMC分型融合范围而于术后与随访时发生冠状面躯干失平衡(失代偿)的发生率分别为26.3%(26/99)和13.2%(9/68)、30.8%(37/120)和12.5%(10/80)、14.0%(15/107)和2.7%(2/74),符合PUMC分型而发生冠状面躯干失平衡的发生率与符合King分型、Lenke分型者比较差异均有统计学意义(P<0.05)。上胸弯和主胸弯的柔韧性与胸腰弯和腰弯比较差异有统计学意义(P<0.05)。结论特发性脊柱侧凸的PUMC分型与Lenke分型比King分型更全面,PUMC分型比King分型和Lenke分型更具手术指导意义。对不同部位的脊柱侧凸采用统一的凸侧Bending位X线片上Cobb角超过25°来定义结构性侧凸并不合适。  相似文献   

11.
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 (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.  相似文献   

12.
Don Dame 《Artificial organs》1996,20(5):613-617
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.  相似文献   

20.
Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号