腰背肌筋膜痛综合征核心肌群的表面肌电信号与肌纤维类型的相关性分析

目的:运用表面肌电检测腰背肌筋膜痛患者腰部核心肌群,通过中位频率及中位频率斜率的分析,判断其肌纤维类型分布规律。方法:2017年10月至2018年3月100例腰背肌筋膜炎患者,男45例,女55例;年龄29～76岁,平均48.5岁;左侧腰背疼痛(左侧疼痛组)40例,右侧腰背疼痛(右侧疼痛组)60例;病程6个月。另有40例腰部无疼痛健康人为对照组,男20例,女20例;年龄29～76岁,平均47.3岁。患者均有不同程度的背部酸痛及背部肌肉僵硬,经临床和影像学检查诊断为腰背肌筋膜炎。使用表面肌电测量3组人群的腰部核心肌肉(多裂肌、髂肋肌、最长肌)在腰背肌等长收缩试验过程中的肌电信号特征,如中位频率及中位频率斜率绝对值。结果:3组多裂肌的中位频率,对照组左侧(133.88±26.61)μV,右侧(131.39±29.81)μV;左侧疼痛组左侧(117.29±10.93)μV,右侧(133.70±17.81)μV;右侧疼痛组左侧(131.36±17.37)μV,右侧(118.28±13.57)μV。3组髂肋肌的中位频率,对照组左侧(106.94±28.01)μV,右侧(114.68±18.96)μV;左侧疼痛组左侧(93.95±11.17)μV,右侧(107.60±27.86)μV;右侧疼痛组左侧(105.93±15.52)μV,右侧(97.27±19.27)μV。3组最长肌的中位频率,对照组左侧(109.24±26.20)μV,右侧(112.58±17.70)μV;左侧疼痛组左侧(95.58±10.83)μV,右侧(108.79±26.39)μV;右侧疼痛组左侧(106.50±17.98)μV,右侧(98.20±11.16)μV。3组多裂肌的中位频率斜率绝对值,对照组左侧0.221±0.109,右侧0.259±0.169;左侧疼痛组左侧0.318±0.184,右侧0.210±0.159;右侧疼痛组左侧0.258±0.169,右侧0.386±0.166。3组髂肋肌的中位频率斜率绝对值,对照组左侧0.241±0.158,右侧0.238±0.128;左侧疼痛组左侧0.330±0.208,右侧0.252±0.171;右侧疼痛组左侧0.249±0.150,右侧0.343±0.144。3组最长肌的中位频率斜率绝对值,对照组左侧0.244±0.252,右侧0.210±0.128;左侧疼痛组左侧0.348±0.255,右侧0.241±0.224;右侧疼痛组左侧0.239±0.155,右侧0.334±0.233。对照组左右侧腰多裂肌、髂肋肌、最长肌的中位频率和中位频率斜率绝对值差异无统计学意义(P0.05);腰痛组疼痛侧多裂肌、髂肋肌、最长肌的中位频率值小于非疼痛侧(P0.05),中位频率斜率绝对值大于非疼痛侧(P0.05)。结论:慢性腰背筋膜痛患者疼痛侧的腰部肌肉耐疲劳程度下降,肌纤维类型百分比转变为以Ⅱ型肌纤维为主。     

腰椎间盘突出症患者腰骶部多裂肌脂肪变化的影像学研究

目的：比较腰椎间盘突出症患者腰骶部多裂肌退变情况。方法：招募健康志愿者和单侧L_4,5腰椎间盘突出患者各35例,每组男20例,女15例,年龄25~55岁。健康志愿者组年龄（35.66±8.73）岁,BMI指数（21.85±1.94）kg/m²;腰椎间盘突出症患者组年龄（36.09±7.70）岁,BMI指数（21.50±1.78）kg/m²,VAS评分（4.40±0.88）分,病程（11.2±7.14）个月,采用核磁共振波谱成像分析,观察L_4,5间隙腰骶部多裂肌脂肪比例、去脂肪化横截面积比例。结果：健康志愿者左侧多裂肌脂肪比例（0.169±0.035）%、去脂肪化横截面积比例（0.699±0.070）%和右侧多裂肌脂肪比例（0.168±0.031）%、去脂肪化横截面积比例（0.712±0.056）%比较,差异无统计学意义（P>0.05）。腰椎间盘突出症患者健侧多裂肌脂肪比例（0.173±0.021）%、去脂肪化横截面积比例（0.695±0.054）%和患侧多裂肌脂肪比例（0.228±0.027）%、去脂肪化横截面积比例（0.629±0.048）%比较,差异有统计学意义（P<0.05）。患者患侧与志愿者左右两侧多裂肌脂肪比例、去脂肪化横截面积比例比较,差异均有统计学意义（P<0.05）;患者健侧与健康志愿者左右侧多裂肌脂肪比例、去脂肪化横截面积比例比较,差异均无统计学意义（P>0.05）。结论：单侧L_4,5腰椎间盘突出症患侧腰骶部多裂肌存在退变,表现为多裂肌面积萎缩、脂肪浸润。     

基于动态肌电图的腰椎间盘突出症诊治和相关因素研究

目的:分析腰椎间盘突出症(lumbar disc herniation,LDH)患者腰背部肌肉活动的动态肌电特征及相关因素,阐明动态肌电在腰椎间盘突出症患者诊治过程中的临床意义。方法:自2014年9月至2021年3月,采用表面肌电图遥测仪检测40例腰椎间盘突出症患者,男14例,女26例;年龄20~61(40.68±10.56)岁;病程1~120(17.75±27.56)个月。另外招募12例正常人作为对照组,男2例,女10例;年龄24~53(36.50±10.30)岁。对所有受试者进行静止站立、躯干屈伸过程中的近胸段竖脊肌、腰段竖脊肌、多裂肌的动态肌电测试。比较两组受试者肌电活动数据(肌电振幅、中位频率、原始肌电图形),分析腰椎间盘突出症患者一般资料与肌电活动数据的相关性。结果:静止站立时,腰椎间盘突出症LDH组受试者右侧及左侧近胸段竖脊肌肌电振幅值较对照组增大(P<0.05)。躯干屈伸时,LDH组受试者右侧及左侧近胸段竖脊肌、腰段竖脊肌、多裂肌肌电振幅均较对照组增大(P<0.05);躯干屈伸时,LDH组受试者右侧及左侧近胸段竖脊肌、腰段竖脊肌、多裂肌中位频率均较对照组增大(P<0.05);躯干屈伸时,LDH组受试者的原始肌电图形与对照组相比明显不同,LDH组受试者的躯干最大限度屈曲维持过程中所测腰背肌肉的肌电活动存在高水平,原始信号中应该规律出现的肌电静止信号不能分辨;躯干屈伸时,LDH组受试者的性别、年龄、体重、身高分别与双侧近胸段、腰段竖脊肌和双侧多裂肌的肌电振幅、中位频率无相关性(P>0.05)。结论:腰椎间盘突出症患者腰背部肌肉存在不同于正常人的特征性表面肌电改变,这些特征更能客观地反映患者的肌肉情况,可以成为腰椎间盘突出症患者诊断和治疗效果评价的有效指标。由此可见,表面肌电图不单是一种检测手段,其可被考虑在LDH的常规诊疗计划之内来指导临床工作。     

表面肌电图在腰椎间盘突出症治疗中应用价值的研究

目的探讨表面肌电图在腰椎间盘突出症治疗中的应用价值;方法腰椎间盘突出症50例,均接受1个月的Mckenzie疗法和本体感觉强化训练,治疗前、后采集双侧竖脊肌在完成等长负荷测试时L4-5或L5-S1水平竖脊肌的表面肌电信号。结果 50例腰椎间盘突出症患者治疗后,显效16例,有效32例,无效2例,改善率为(54.25±15.74)%。治疗前,患侧竖脊肌AEMG较健侧显著降低,MFs绝对值较健侧显著增大(P0.05);与治疗前相比,治疗后患侧AEMG显著地增加(P0.05),患侧MFs绝对值显著地降低(P0.05),治疗后健、患侧AEMG和MFs差异无显著性(P0.05)。结论表面肌电图可作为治疗腰椎间盘突出症疗效评定的客观依据,具有较好的临床应用价值。     

强筋功法训练对腰骶部多裂肌影响的超声分析

目的 :观察强筋功法训练对腰骶部多裂肌的影响。方法 :招募健康志愿者30例,男21例,女9例;年龄25~55岁,平均(31.30±6.48)岁;BMI指数18.1~24.9 kg/m~2,平均(21.70±1.95)kg/m~2。采用超声影像分析健康志愿者行仰卧抬腿强筋力时仰卧位及仰卧抬腿30°、60°、90°多裂肌厚度,行双手攀足固肾腰时坐位屈髋、前屈至极限位、前探至极限位多裂肌厚度。结果:仰卧抬腿强筋力时,仰卧抬腿0°时多裂肌平均厚度为(16.867±2.460)mm,仰卧抬腿30°时多裂肌平均厚度为(19.010±2.510)mm,仰卧抬腿60°时多裂肌平均厚度为(22.477±2.220)mm,仰卧抬腿90°时多裂肌平均厚度为(27.593±2.370)mm,差异有统计学意义(F=423.619,P0.05)。双手攀足固肾腰时,坐位屈髋时多裂肌平均厚度为(25.810±2.440)mm,前屈位多裂肌平均厚度为(15.677±2.130)mm,前探位多裂肌平均厚度为(15.533±2.110)mm,差异有统计学意义(F=597.789,P0.05)。结论:健康志愿者在行强筋功法时,多裂肌的厚度随仰卧抬腿度数的增加而增加,随着前屈度数的增加而减小,可以通过特定动作训练改变多裂肌的伸缩状态,从而实现锻炼多裂肌的目的。     

MRI技术在腰椎间盘突出症中对脊柱多裂肌的定量分析

目的探讨腰椎间盘突出症伴神经压迫患者腰椎多裂肌的组成,通过采用磁共振成像(MRI)的定性和定量测量方法进行磁图分析。方法共纳入50例符合标准患者。由两位放射科医师回顾性测量所有患者多裂肌在MRI上的信号强度,并对单侧关节下腰椎间盘突出症患者的脂肪含量采用5点分级系统进行视觉分级。比较疝侧和对侧的表现,并评估了脂肪含量与神经压迫严重程度和症状持续时间的关系。结果在定量测量和定性评分方面,受影响一侧的多裂肌肉的信号强度明显高于对侧肌肉。在受影响的多裂肌肉中,神经受压程度与症状持续时间、脂肪含量呈显著相关(P0.05)。结论与对侧相比,腰椎间盘突出症同侧多裂肌脂肪含量较高。关于脂肪浸润的肌肉成分的直观分级似乎和定量测量一样有用。     

肌电生物反馈治疗分娩性臂丛神经麻痹术后腕背伸功能的疗效分析

目的 初步评价肌电生物反馈电刺激对臂丛神经移位术后分娩性臂丛神经麻痹(产瘫)患儿腕背伸功能的疗效.方法 根据纳入标准,选取30例行臂丛神经移位术后的产瘫患儿,在服用神经营养药物治疗和康复训练的基础上,给予患侧桡侧腕长伸肌肌电生物反馈电刺激治疗.在治疗前和治疗4周后评定患儿腕背伸主动关节活动度和桡侧腕长伸肌自发肌电均值,进行统计分析.结果 30例患儿全部获得随访,腕背伸主动关节活动度治疗前为(0.00±14.20)°,治疗后为(24.57± 13.79)°,两组差异有统计学意义(P＜0.01).桡侧腕长伸肌自发肌电均值治疗前为(69.57±39.57)μV,治疗后为(529.30±293.17)μV,两组差异有统计学意义(P＜0.01).结论 肌电生物反馈电刺激有助于改善臂丛神经移位术后产瘫患儿的腕背伸功能.     

核心稳定性训练对腰椎间盘突出症患者表面肌电时频参数的影响

目的通过核心肌群表面肌电时频参数的变化分析核心稳定性训练在腰椎间盘突出症患者康复治疗中的应用效果。方法纳入60例腰椎间盘突出症,采用随机数字表法分组,对照组30例接受常规物理治疗,观察组30例在常规物理治疗基础上增加核心稳定性训练。比较2组治疗4周、8周后的疼痛NRS评分、JOA评分、ODI指数、表面肌电图测试结果。采集腹直肌、腹外斜肌、竖脊肌、多裂肌及臀中肌的积分肌电值(IEMG)、均方根值(RMS)和中位频率值(MF)进行统计学分析。结果治疗4周后观察组疼痛NRS评分、JOA评分、ODI指数与对照组比较差异无统计学意义(P0.05);治疗8周后观察组各指标明显优于对照组,差异有统计学意义(P0.05)。治疗4周后,观察组与对照组腹直肌、腹外斜肌、竖脊肌、多裂肌及臀中肌的IEMG、RMG、MF差异无统计学意义(P0.05);治疗8周后,观察组各部位肌肉IEMG、RMG、MF高于对照组,差异有统计学意义(P0.05)。结论核心稳定性训练可持续提高腰椎间盘突出症患者核心肌群的募集能力和耐疲劳性能,并同时改善其腰痛症状及功能障碍,效果优于常规物理治疗。     

肌电图定量评估半面短小咬肌发育不良的临床应用

目的探索肌电图在半面短小咬肌功能定量评估中的可行性。方法选取自2016年6月至2018年6月就诊的33例CT明确诊断为单侧半面短小患儿。利用Bio Neuro多参数生物反馈仪测定患儿下颌姿势位(MPP)及3次最大自愿收缩状态(MVC)的两侧咬肌电位值,分别取波幅均方根值记为静息/活动平均电位;取3次活动平均电位的平均值,采用配对t检验分析患儿健、患侧平均电位差异。计算半面短小患儿患侧/健侧咬肌活动平均电位的比值(A/U),提出基于A/U的半面短小咬肌功能定量分类。结果患侧咬肌平均活动电位(37.97±20.40)m V明显低于对侧(70.35±33.70)m V,其差异具有统计学意义(P0.001)。咬肌功能定量分类MFC将半面短小患儿分为四型:MFCⅠ型(A/U0.8)、MFCⅡ型(0.6A/U≤0.8)、MFCⅢ型(0.3A/U≤0.6)和MFCⅣ型(A/U≤0.3)。结论半面短小患儿咀嚼肌活动发生改变,约有75.8%(25/33)的患儿存在患侧咬肌功能受累;基于A/U提出的咬肌功能定量分类,能在一定程度上评估半面短小咬肌功能情况。     

微创多裂肌间隙入路减压椎间融合治疗合并骨质疏松单阶段腰椎间盘突出症的研究

目的探讨微创多裂肌间隙经椎间孔减压腰椎间植骨融合治疗单阶段腰椎间盘突出症合并骨质疏松的效果。方法 2007年7月～2008年7月,对收治的37例单阶段腰椎间盘突出症合并骨质疏松患者,作微创多裂肌间隙经椎间孔减压腰椎间植骨融合固定治疗,手术后随访观察椎体间植骨融合情况和临床效果,术前、术后和末次随访时采用ODI及VAS评估患者功能。结果 37例患者随访14～20个月,平均17个月,VAS评分术前为8.7±0.77分,术后1个月为4.67±0.77分,末次随访为1.77±0.88分,与术前比较均有显著性差异(P<0.01)。ODI评分术前为39.61±2.71分,后一个月为17.47±3.31分,末次随访为5.70±1.67分,与术前比较均有显著性差异(P<0.01)。椎间隙高度术前为6.98±0.87mm,术后一个月为12.71±0.75mm,末次随访为9.87±0.97mm,与术前比较均有显著性差异(P<0.01)。4例患者术后出现单侧小腿、足背痛觉过敏和姆伸肌力减弱的症状加重,经治疗后恢复。结论微创多裂肌间隙经椎间孔减压腰椎间植骨融合治疗合并骨质疏松的单阶段腰椎间盘突出症可取得满意效果。     

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.