青少年特发性脊柱侧凸后路矫形术后 新发上胸弯转归分析

  目的 对术前无上胸弯的青少年特发性脊柱侧凸患者行后路矫形手术后新发上胸弯的情 况进行转归分析。 方法回顾性分析21 例患者的影像学资料, 平均随访时间19.8 个月, 对新发上胸弯 的冠状面Cobb 角、T1倾斜、放射学肩高度等影像学参数进行测量与分析。 结果 21 例患者术前主胸弯 冠状面Cobb 角平均为54.3°, 末次随访时平均为14.1°, 手术矫形率平均为74.6豫。术前5 例患者为负性 T1倾斜, 16 例为T1水平;术后均出现正性T1倾斜及新发上胸弯, T1倾斜平均6.0°, 新发上胸弯冠状面 Cobb 角平均为16.0°;末次随访时T1倾斜平均4.0°, 上胸弯平均为13.2°, 18 例患者仍存在正性T1倾斜, 17 例患者仍存在10°以上的上胸弯。术前5例患者放射学肩高度为双肩等高, 16 例为右肩高;术后19 例患者为左肩高, 6 例患者存在双肩不平衡;末次随访时有14 例患者为左肩高, 5 例患者存在双肩不平 衡。末次随访时与术后相比, T1倾斜程度、上胸弯冠状面Cobb 角均有改善(t=2.755, P=0.009;t=2.142, P= 0.038), 但上胸弯比例、左肩高发生率、双肩失平衡发生率差异均无统计学意义(χ²=4.421, P=0.107;χ²= 0.123, P=1.000;χ²=3.535, P=0.130)。 结论 青少年特发性脊柱侧凸患者后路手术矫形时新发上胸弯不易 自行代偿, 且易对双肩平衡产生影响, 应以预防其发生为主。     

Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学评估

[目的]对行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学危险因素进行分析。[方法]选择长海医院行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者80例,随访至少2年。测量T1倾斜(T1 tilt)、锁骨角(clavicle angle,CA)、影像学肩高(radiographic shoulder height,RSH)等影像学参数。根据RSH分级的绝对值术后是否大于术前,将其分为术后平衡组与失平衡组,并对两组患者的影像学参数进行对比分析。[结果]术后双肩失平衡的发生率为22.5%。双肩失平衡组正性T1倾斜、正性锁骨角的比例远高于平衡组(P<0.001)。术前双肩水平的患者术后更易出现双肩失平衡(25.8%vs 83.3%,P<0.001)。25.8%的双肩平衡患者上胸弯Cobb角≥30°,而双肩失平衡患者该比例高达55.6%(P=0.018);50.0%的双肩平衡患者主胸弯与上胸弯的Cobb角差值≥25°,而双肩失平衡患者该比例仅为22.2%(P=0.036)。平衡组30.6%患者随访时主胸弯与上胸弯矫正率的差值≥1.8,失平衡组中该比例达61.1%(P=0.019)。[结论]T1倾斜、锁骨角、术前双肩平衡状态、上胸弯Cobb角、主胸弯与上胸弯的Cobb角差值及主胸弯与上胸弯矫正率的比值是较好的预测Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学参数。     

先天性脊柱侧凸合并高肩胛征的影像学特征

目的:探讨先天性脊柱侧凸(congenital scoliosis,CS)合并高肩胛征患者的影像学特征,并分析高肩胛征与双肩平衡的相关性。方法:回顾性分析2000年1月～2015年10月在我科以脊柱畸形首诊且影像学资料完整的24例CS合并高肩胛征患者,其中男11例,女13例,平均年龄11.8±6.0岁(2～31岁)。通过站立位全脊柱正侧位X线,测量并记录患者侧凸类型、Cobb角、顶椎位置、上下端椎位置、双肩高度差、高肩胛的位置及半椎体位置等。并对双肩高度差和弯型参数进行Spearman相关性分析。结果:24例患者均表现为颈胸椎或胸椎侧凸畸形,平均侧凸Cobb角49.5°±23.3°。侧凸顶椎位于T1～T11,其中16例患者表现为单节段或多节段半椎体畸形,半椎体发生于T4及以上节段10例;合并肋骨畸形15例,其中9例发生于脊柱侧凸的凹侧,3例发生于侧凸凸侧,3例发生于侧凸两侧。高肩胛发生于脊柱侧凸凸侧15例(62.5%)、凹侧7例(29.2%)、双侧2例(8.3%)。高肩胛位于侧凸凸侧的15例患者均为凸侧肩高于凹侧;高肩胛位于侧凸凹侧的7例患者中,5例凹侧肩高于凸侧,2例凸侧肩高于凹侧。双肩高度差平均为15.7±21.0mm。Spearman相关性分析显示,双肩高度差与Cobb角、顶椎位置、上下端椎位置等无明显相关性(P0.05)。结论 :CS合并高肩胛征患者多表现为颈胸段和胸段侧凸畸形,以T4以上节段半椎体多见,高肩胛征及合并的肋骨畸形均多见于脊柱侧凸的凸侧,而双肩高度差与弯型特征无明显相关性。     

青少年特发性脊柱侧凸主胸弯融合后未融合上胸弯的变化及其与肩部平衡的关系

【摘要】 目的：探讨青少年特发性脊柱侧凸（AIS）患者主胸弯融合后未融合上胸弯的变化及其与肩部平衡的关系。方法：回顾性分析2008年1月~2010年12月在我院接受手术治疗的AIS患者,选取年龄10～18岁,Lenke分型为Lenke 1、2、3、4型,右胸弯且Cobb角＜80°,采用后路椎弓根螺钉系统固定矫形,固定融合上端椎在T4或T4以下,随访时间2年以上的患者,排除翻修手术和截骨手术患者。术前根据Lenke分型判断上胸弯是否为结构性,分成结构性上胸弯组和非结构性上胸弯组,统计比较两组术前、术后3个月和末次随访时外观肩部平衡以及影像学各项参数的变化。结果：共有62例患者纳入本研究,平均年龄14.4岁,随访时间24~62个月,平均36.4个月,其中结构性上胸弯组17例,非结构性上胸弯组45例。两组患者术后上胸弯均能自发性矫正,末次随访时,上胸弯Cobb角平均由27.9°减小至19.4°,T1倾斜角由-0.21°增加至4.7°,第一肋倾斜角（FRT）由0.4°增加至3.7°,锁骨角（CA）由-1.5°增加至0.8°,双肩高度差（CSH）由-13.0mm增加至5.2mm,改变均有统计学意义（P=0.000）。Pearson相关性分析显示,T1倾斜角的改变（术后T1倾斜角-术前T1倾斜角）与CSH变化（术后CSH-术前CSH）有较强相关性（r=0.624,P=0.000）,术后主胸弯的矫正率和FRT与CSH变化为中等程度相关（r=0.437,0.345,P=0.007,0.006）,术前主胸弯Cobb角与CSH变化为弱相关（r=0.262,P=0.040）。上胸弯Cobb角及柔韧性、主胸弯柔韧性、T1倾斜角等参数与CSH变化无统计学相关性。结论：AIS患者结构性与非结构性上胸弯在主胸弯矫正以后均有自发性矫正现象,但T1倾斜角、第一肋倾斜角和双肩高度差均会增加。右胸弯患者左肩被抬高的程度与T1倾斜角增加的程度、主胸弯的矫正率及术后第一肋倾斜角相关。     

青少年特发性双胸弯患者肩部影像学平衡与美学平衡的相关性研究

目的 探讨Lenke2型青少年特发性脊柱侧凸(adolescent idiopathic scoliosis, AIS)患者肩部影像学指标与美学指标之间的相关性.方法 对34例Lenke2型的AIS患者进行研究,提出了评价AIS患者肩部美学平衡的6个指标:内侧双肩高度差(Shi)、外侧双肩高度差(Sho)、肩部面积指数1(SAI1)、肩部面积指数2(SAI2)、肩角(α1)、腋窝角(α2)并在照片上进行测量;同时在X线片上测量7个评价AIS患者肩部影像学平衡的指标:T1倾斜(T1)、第一肋角(FRA)、锁骨角(CA)、喙突高度差(CPH)、锁骨助骨交点高度差(CRCI)、第一肋锁骨距离差(FRCH)、斜方肌不对称性(TL).美学指标与影像学指标之间进行相关分析.结果 Shi与各影像学指标之间的相关系数范围为-0.12～0.61,其中与T1、FRA、CA、CPH、CRCI呈显著相关.Sho与各影像学指标之间的相关系数范围为-0.22～0.74,其中与T1、FRA、CA、 CPH、CRCI. FRCH呈显著相关.但是,所有的相关系数都小于0.8.SAI1、SAI2、α1、α2与影像学指标之间的相关系数同样也都小于0.8.结论 影像学指标可以部分反映肩部的美学外观,但是没有一个影像学指标可以精确地反映肩部的美学外观.因此,建议在评价Lenke2型AIS患者肩部平衡时,在采用影像学指标的同时,美学指标应作为一种补充.     

术前影像学评估在内窥镜下经椎间孔入路手术治疗腰椎间盘突出症中的作用

目的:探讨术前影像学评估在制定内窥镜下经椎间孔入路治疗腰椎间盘突出症手术方案中的作用.方法:回顾性分析2008年7月～2012年12月我院191例采用内窥镜下经椎间孔入路治疗腰椎间盘突出症患者的影像学资料,术前影像学评估指标包括椎间盘突出节段、突出位置、髂嵴高度、髂嵴最高点和S1椎弓根内侧缘所连直线与S1椎体上缘水平线的夹角(α)、L5椎弓根下缘5mm(即L5椎弓根下缘距穿刺针的距离)与髂嵴最高点之间的连线(d)、椎间隙后缘高度(H1)、椎间孔的垂直高度(H2).将d与S1椎体上缘相交的位置分为3个区域,1区:L5/S1椎间隙中点以及对侧区域;2区:L5/S1椎间隙中点(不含此点)到S1椎弓根内侧缘;3区:S1椎弓根内侧缘以外的区域.所有患者均观察椎间盘突出节段、突出位置并测量H1、H2,其中L5/S1椎间盘突出者加测髂嵴高度、α、d、d所落手术区域.Hl≤4mm及H2≤15mm为椎间孔狭窄.记录术中18G穿刺针穿刺达到靶向手术区域的次数.结果:L5/S1椎间盘突出85例(44.50％),L4/5及以上突出106例(55.50％).突出位置在中央区17例(8.90％),在侧隐窝区146例(76.44％),在椎间孔区24例(12.57％),在椎间孔外侧区(极外侧区)4例(2.09％);椎间孔狭窄9例(4.71％).85例L5/S1椎间盘突出患者中,髂嵴高度平对L4椎体中、上1/3者3例(3.53％),平对L4椎体下1/3及以下者82例(96.47％);α≤30°者69例(81.18％),30°＜α≤40°者16例(18.82％);d落在1区68例(80.00％),2区14例(16.47％),3区3例(3.53％).当髂嵴高度平对L5椎体及以下者时,穿刺次数平均为16次(12～41次);平对L4椎体下1/3～L4/5椎间隙时,穿刺次数平均为29次(16～46次);平对L4椎体中、上1/3时,穿刺次数平均为39次(36～44次).结论:髂嵴高度、α、d及d所落手术区域主要影响L5/S1椎间盘突出的手术操作,对于突出节段在L4/5及以上者,穿刺针可水平进入而基本上不受上述影像学因素的影响.椎间盘突出节段、突出位置、H1、H2则对所有节段操作均有影响.     

心脏移植术前血N端B型利钠肽原水平与术后早期受者存活率的关系

目的 探讨心脏移植术前血N端B型利尿钠肽原(NT-proBNP)水平与术后早期受者存活率的关系.方法 采用免疫法测定284例拟接受心脏移植的心力衰竭患者移植前血NT-proBNP水平,按NT-proBNP水平将284例患者分为≤5000 nmol/L组(≤5000组,237例)和＞5000 nmol/L组(＞5000组,47例),比较两组受者的术前一般情况、不同原发病者的NT-proBNP水平、两组围手术期体外膜肺氧合(ECMO)技术应用率及死亡率.采用Kaplan-Meier法计算两组受者1年存活率.结果 ＞5000组术前肺毛细血管楔压为(25.1±7.4)mm Hg(1 mm Hg=0.133 kPa),明显高于≤5000组的(21.4±9.2)mm Hg(P＜0.05)；心脏指数为(1.8±0.5)L·min-1·m-2,明显低于≤5000组的(2.1±0.6)L·min-1·m-2 (P＜0.05).＞5000组围手术期需用ECMO支持者占14.9％(7/47),ECMO相关死亡率为71.4％(5/7),1年存活率为91.3％；≤5000组围手术期需用ECMO支持者占6.8％(16/237),ECMO相关死亡率为12.5％(2/16),1年存活率为96.9％,2个组ECMO应用率、ECMO相关死亡率以及受者1年存活率的差异均有统计学意义(P＜0.05).结论 术前血NT-proBNP水平较高(＞5000 nmol/L)者围手术期ECMO应用率和1年死亡率均较高；术前测定血NT-proBNP水平有助于心脏移植时机的把握.     

先天性脊柱侧凸美学指标与影像学指标的相关性研究

目的探讨分节障碍型先天性脊柱侧凸(congenital scoliosis, CS)患者的美学指标与影像学指标的相关性, 以及美学指标的临床意义。方法回顾性分析27例分节障碍型CS患者的临床及影像学资料, 所有患者均摄正、侧位全脊柱X线片, 以及自然站立位背部及前屈位的大体照片。大体照片测量以下7个美学指标:肩部面积指数1(shoulder area index 1, SAI1)、肩部面积指数2(shoulder area index 2, SAI2)、腰部面积指数(lumbar area index, LAI)、肩角(shoulder angle, α1)、腋窝角(axilla angle, α2)、左右腰角差(right and left waist angle difference, RLWAD)和剃刀背指数(hump index);同时在患者术前X线片上测量7个影像学指标:影像肩高差(radiographic shoulder height difference, RSHD)、T1倾斜(T1 tilt)、第一肋角(first rib angle, FRA)、锁骨角(clavic...     

腰段半椎体畸形及其远端椎体的影像学特点

目的:分析腰段半椎体畸形及其远端腰椎和骶骨的影像学特点,为远端融合椎的选择及手术策略提供依据。方法:对93例手术治疗的腰段半椎体畸形患者的术前影像学资料进行回顾性分析。其中男46例,女47例,年龄10.5±7.2岁(2~42岁)。所有病例均行全脊柱X线片及三维CT检查,测量侧后凸的节段性Cobb角及冠状面、矢状面平衡;通过CT三维重建,对半椎体畸形进行分型;测量站立正位及凹侧Bending像上L4、L5和S1椎体的倾斜度(即相应椎体上终板与双侧髂嵴最高点连线的夹角),计算L4和L5倾斜的柔韧性。根据年龄将患者分为三组:A组,年龄≤6岁,B组,年龄7~12岁,C组,年龄≥13岁,对各组患者数据进行统计学分析。结果:88例(94.6%)患者为单个半椎体,5例患者为2个半椎体。其中55个(56.1%)半椎体为完全分节型,43个半椎体为不完全分节型。节段性侧凸Cobb角42.5°±15.9°(12°~93°),柔韧性为(26.6±17.9)%(0~90%),顶椎椎体偏距为22.4±14.5mm(2~72mm)。51例(54.8%)患者有局部后凸,Cobb角度为20.5°±20.3°(2°~94°)。13例患者冠状面失平衡,19例患者矢状面失平衡。L4、L5和S1椎体在站立位正位X线片上的倾斜度分别为23.5°±10.2°、17.2°±9.0°和9.8°±5.9°;18例S1椎体倾斜度≥15°,其中5例倾斜度≥20°。L4和L5在凹侧Bending像上的倾斜度分别为14.5°±10.6°和12.0°±8.8°,椎体倾斜的柔韧性分别为(43.4±29.1)%和(39.3±29.5)%。A、B、C三组L4椎体在Bending像上的倾斜度和柔韧性在分别为7.6°±6.6°、13.9°±10.5°、21.1°±9.8°和(59.1±34.0)%、(42.9±25.7)%、(31.4±22.0)%,L5椎体在Bending像上的倾斜度和柔韧性分别为7.0°±6.6°、11.1°±8.5、17.2°±8.7°和(41.8±33.8)%、(39.1±23.4)%、(25.6±21.9)%,三组L4、L5椎体在Bending像上的平均倾斜度和柔韧性有显著性差异(P0.05)。结论:腰段半椎体畸形常伴有远端椎体的倾斜,L4和L5在Bending像上的倾斜度随年龄增加而增加,但柔韧性随年龄增加而减低。术前对L4、L5和S1椎体倾斜度以及L4和L5倾斜的柔韧性测量对决定远端融合椎及矫形策略具有重要意义。     

青少年特发性脊柱侧弯患者肩部影像学与肩部外观的相关性研究

[目的]对新定义的肩部影像学参数进行分析,进一步研究青少年特发性脊柱侧弯患者(adolescent idiopathic scoliosis,AIS)肩部影像学与肩部外观的相关性.[方法]选取本院接受治疗的连续35例含主胸弯青少年特发性脊柱侧弯患者,Lenke 1型21例,Lenke 2型14例,主胸弯Cobb角平均(48±7.3)°,上胸弯Cobb角平均(21±4.5)°.均拍摄自然站立位脊柱X线片及肩背部外观照,量取肩部影像学参数T1倾斜角、锁骨角、锁骨胸廓交点差、喙突高、锁骨差1、锁骨差2,及两个肩部外观参数临床肩高1、临床肩高2.对肩部影像学参数与外观参数分别进行相关分析,探讨锁骨差1、锁骨差2与肩部外观的相关性.[结果]除T1倾斜角外,所研究的影像学参数与外观参数显示明显的相关性(P＜0.05);但仅有锁骨差1与临床肩高2、锁骨差2与两个外观参数有较高的相关关系(r＞0.80),其中锁骨差2与临床肩高2显示最强的相关关系(P＜0.01,r=0.97);临床肩高2较临床肩高l与肩部影像学参数显示更强的相关性.[结论]肩部影像学参数锁骨差2可以更好反映临床外观肩高,参考影像学资料可以较准确地评价患者的部分肩部外观特征.     

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.     

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.     

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.     

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.