退行性腰椎后滑脱的节段分布及与腰骶部矢状位平衡参数的关系

目的 探索腰椎后滑脱节段分布及与腰骶部矢状位平衡参数的相关性,揭示腰椎后滑脱发生机制。方法 选取2016年9月—2019年6月海军军医大学附属长征医院收治的腰椎后滑脱患者47例,调查其腰椎后滑脱节段分布规律,并将其分为上腰椎后滑脱组（L_1~3,34例）与下腰椎后滑脱组（L_4~5,13例）;选取同期入院的近似健康的患者29例作为对照组。比较3组患者腰椎前凸角（LL）、骶骨倾斜角（SS）、骨盆倾斜角（PT）、骨盆入射角（PI）的差异。结果 47例患者共56个节段后滑脱,其中L₁ 5例、L₂ 13例、L₃ 25例、L₄ 11例、L₅ 2例。与对照组相比,上腰椎后滑脱组LL、SS增大,PT减小,差异有统计学意义（P<0.05）,PI差异无统计学意义（P>0.05）;下腰椎后滑脱组LL、SS减小,PT增大,差异有统计学意义（P<0.05）,PI差异无统计学意义（P>0.05）。结论 腰椎后滑脱好发于L₃,其次为L₂、L₄。腰椎后滑脱与腰骶部矢状位失衡密切相关。当上腰椎后滑脱时,LL、SS增大,而PT减小;当下腰椎后滑脱时,LL、SS减小,甚至变为后凸,而PT增大。     

腰椎椎间隙高度与上位椎体高度的比值与椎间盘退行性变Pfirrmann分级的相关性

目的 探讨腰椎椎间隙高度与上位椎体高度的比值与椎间盘退行性变程度之间的关系,为腰椎椎间盘退行性疾病的诊断和治疗提供客观准确的依据。方法 回顾性分析2019年1月—2019年6月来本院就诊的61例腰椎椎间盘退行性变患者临床资料。在腰椎侧位X线片上测量腰椎椎间隙及相应上位椎体的高度,并计算椎间隙高度与上位椎体高度的比值;在腰椎矢状位MRI上评估腰椎椎间盘退行性变Pfirrmann分级;比较不同Pfirrmann分级椎间盘的椎间隙高度与上位椎体高度比值的差异,并采用Spearman相关分析研究椎间隙高度与上位椎体高度比值与相应节段椎间盘Pfirrmann分级之间的相关性。结果 除L₁/L₂节段,其余各节段椎间隙高度与上位椎体高度比值均随着Pfirrmann分级增加而逐渐减小,差异均有统计学意义（P < 0.05）。相同Pfirrmann分级的不同节段椎间盘之间椎间隙高度与上位椎体高度比值差异无统计学意义（P > 0.05）。Spearman相关分析结果显示,L₂/L₃、L₃/L₄、L₄/L₅、L₅/S₁节段Pfirrmann分级与椎间隙高度与上位椎体高度比值呈负相关（r =-0.568,P < 0.05）。结论 临床上测量L₂/L₃、L₃/L₄、L₄/L₅、L₅/S₁节段椎间隙高度与上位椎体高度比值对腰椎椎间盘退行性疾病的诊断可能具有重要意义。     

脊柱－骨盆矢状位参数及关节突关节角度对退变性腰椎滑脱的影响

目的：探讨脊柱-骨盆矢状位参数及关节突关节角度对退变性腰椎滑脱的影响及相关性研究。方法：以2016年7月至2019年9月确诊的120例L₄-L₅单节段退变性滑脱患者为观察对象（滑脱组）,以性别和年龄相匹配的120例L₄-L₅节段退变性椎管狭窄患者为对照（对照组）。通过影像学资料测量如下参数：骨盆入射角（pelvic incidence,PI）,骨盆倾斜角（pelvic tilt,PT）,骶骨倾斜角（sacral slope,SS）,腰椎前凸（lumbar lordosis,LL）,胸椎后凸（thoracic kyphosis,TK）,矢状面平衡（sagittal vertical axis,SVA）,L₄-L₅头侧关节突关节角,尾侧关节突关节角及小关节不对称性。比较两组患者参数的差异并对有意义参数行Logistic回归分析。对退变性腰椎滑脱患者关节突关节方向与脊柱-骨盆参数进行相关性分析。结果：两组患者在PI、PT、LL、SVA、头侧关节突关节角、尾侧关节突关节角差异有统计学意义（P<0.05）;Logistic回归分析发现PI、PT及头侧关节突关节角是腰椎滑脱程度的危险因素（P<0.05）。滑脱组头侧关节突关节矢状化与PI、PT呈现显著相关（P<0.05）。结论：高PI、PT及头侧关节突关节矢状化是腰椎滑脱的危险因素,并且关节突关节矢状化程度和大PI、PT密切相关。     

腰椎退行性疾病手术病人术前邻近节段椎间盘的退变情况及分布规律

目的 观察腰椎退行性疾病手术病人术前邻近节段椎间盘的退变情况及分布规律。方法 回顾性分析济南军区总医院2012年1月至2016年2月收治的503例行手术治疗腰椎退行性疾病病人的术前临床资料,其中男240例（47.71%）,女263例（52.29%）;年龄为20~84岁,平均48.8岁。腰椎间盘突出症352例,退变性腰椎滑脱症91例,退变性腰椎管狭窄症60例。通过术前X线片评估腰椎稳定性;基于术前MRI,采用Pfirrmann分级标准评价腰椎间盘退变程度,记录Modic改变、高信号区域及许莫氏结节的发生情况。结果 503例中仅5例为单节段退变,12例为跳跃节段退变,余486例均为多节段退变。共1 863个（1 863/2 515,74.08%）腰椎间盘发生退变,5个节段椎间盘（L_1~2、L_2~3、L_3~4、L_4~5、L₅~S₁）均退变的病人比例为39.56%（199例）。不稳定节段数为127个,Modic改变为188个,高信号区域为241个,许莫氏结节节段数为161个。30岁以下男性病人腰椎间盘退变率较女性高;随着年龄增长,女性病人椎间盘退变率增加,退变程度加重。腰椎不稳、Modic改变、高信号区和许莫氏结节均与椎间盘退变存在明显相关性（P均＜0.05）。某一腰椎节段（L_3~4、L_4~5、L₅~S₁）椎间盘发生Pfirrmann Ⅳ、Ⅴ级退变时,邻近节段椎间盘退变（Pfirrmann Ⅲ+Ⅳ+Ⅴ级）比例均超过了80%,且严重退变（Pfirrmann Ⅳ+Ⅴ级）比例也较高,超过60%。结论 术前邻近节段椎间盘退变广泛存在,在临床工作中要予以重视。     

胸椎后凸角与骨盆入射角对低度腰椎滑脱症矢状位平衡的影响

目的 评估低度腰椎滑脱患者矢状位失衡情况,并探讨维持低度腰椎滑脱矢状位平衡的主要代偿机制。方法 纳入2016年6月—2017年6月在上海市嘉定区中医医院确诊为单节段低度腰椎滑脱症的60例患者,其中30例为MeyerdingⅠ度滑脱（MeyerdingⅠ度组）,30例为MeyerdingⅡ度滑脱（MeyerdingⅡ度组）。纳入同期30名X线检查脊柱-骨盆无影像学异常的受试者作为对照组。收集患者性别、年龄、体质量指数（BMI）等一般资料,并利用术前站立位脊柱全长侧位X线片测量相关参数：最大胸椎后凸角（maxTK）、最大腰椎前凸角（maxLL）、骶骨倾斜角（SS）、骨盆倾斜角（PT）、骨盆入射角（PI）及矢状位偏移（SVA）。采用秩相关分析探讨滑脱程度与脊柱-骨盆参数的相关性,采用单因素方差分析比较不同程度滑脱患者及对照组脊柱-骨盆参数的差异。结果 腰椎滑脱程度与maxTK呈负相关（r_s=-0.512,P<0.05）,与PI（r_s=0.621,P<0.05）、SS（r_s=0.385,P<0.05）和PT（r_s=0.573,P<0.05）均呈正相关,而与年龄、BMI、SVA和maxLL之间无明显相关性。MeyerdingⅠ度和Ⅱ度滑脱组maxTK均小于对照组,差异有统计学意义（P<0.05）,但Ⅰ度和Ⅱ度滑脱组之间差异无统计学意义（P>0.05）;MeyerdingⅠ度和Ⅱ度滑脱组PI均大于对照组,且Ⅱ度滑脱组PI大于Ⅰ度滑脱组,差异均有统计学意义（P<0.05）。结论 PI增大与腰椎滑脱的发生和进展密切相关,TK降低可能是维持低度腰椎滑脱患者矢状位平衡的主要代偿机制。     

不同年龄颈椎病患者颈椎椎间盘退行性变与颈椎矢状位参数之间的关系

目的 探讨不同年龄颈椎病患者颈椎椎间盘退行性变与颈椎矢状位参数之间的关系。方法 选择2018年1月—2019年5月收治的102例颈椎病患者作为研究对象。采用改良Pfirrmann分级评价颈椎椎间盘退行性变情况,将患者分为严重退行性变组和非严重退行性变组。在颈椎侧位X线片上测量C₂~T₁各节段椎间角度和椎间盘高度、C_2~7前凸角、C_2~7矢状面轴向距离（SVA）、C₇倾斜角。分析不同年龄患者（≥65岁和<65岁）颈椎退行性变程度与颈椎矢状位参数之间的关系。结果 所有患者C₅/C₆椎间角度与椎间盘高度正相关（r=0.290）、与改良Pfirrmann分级负相关（r=-0.236）。在62例非老年患者（<65岁）中,严重退行性变组（10例）的C_2~7前凸角比非严重退行性变组（52例）小,差异有统计学意义（P<0.05）。在40例老年患者（≥65岁）中,严重退行性变组（11例）的C_2~7前凸角与非严重退行性变组（29例）相比,差异无统计学意义（P>0.05）。老年患者的C_2~7前凸角和C₇倾斜角均大于非老年患者,差异有统计学意义（P<0.05）,且C_2~7前凸角与C₇倾斜角正相关（_r=0.525）。老年患者与非老年患者的SVA差异无统计学意义（P>0.05）。结论 颈椎病患者的C_2~7前凸角及C₇倾斜角随着年龄的增加而增大。在非老年患者中,严重的颈椎椎间盘退行性变会导致C_2~7前凸角减小;在老年患者中,颈椎椎间盘退行性变程度与C_2~7前凸角无关。     

训练致青年腰椎峡部裂的病因分析

目的 调查分析训练伤导致的腰椎峡部裂的发生原因，为降低腰椎峡部裂发生率提供理论依据。方法 对2016年1月—2021年3月解放军总医院第七医学中心收治的因训练导致腰椎峡部裂的234例患者进行问卷调查，记录患者身高、体质量、日常训练项目、训练强度、受伤时姿势、受伤时从事的训练项目、骨折部位等资料，并进行统计学分析，总结腰椎峡部裂的好发部位、危险因素等。结果 训练导致的腰椎峡部裂好发于L₅（发生率为85.0%），发生率显著高于L₃、L₄，差异均有统计学意义（P<0.05）。负重行进和负重蹲起造成腰椎峡部裂的发生率显著升高。受伤瞬间腰部姿势：后伸102例（43.6%），前屈49例（20.9%），旋转39例（16.7%），侧曲12例（5.1%），不确定32例（13.7%），训练中腰椎在后伸状态下更容易发生峡部裂。结论 腰椎在后伸状态下峡部剪切力增大，负重会造成峡部剪切力进一步增大而导致骨折，负重行进及负重蹲起是最易造成腰椎峡部裂的训练项目。     

青年L5峡部应力骨折患者上关节突间距的解剖学特点

目的 探讨青年L₅峡部应力骨折患者L₅双侧上关节突间距的解剖学特点。方法 回顾性分析2018年3月—2019年9月解放军总医院第七医学中心收治的21例青年男性L₅峡部应力性骨折患者的影像学资料（应力骨折组），并与24例健康青年男性志愿者影像学资料进行对比（对照组）。所有入组对象均拍摄腰椎CT及三维重建，并在CT上测量L₅双侧上关节突顶点间距（a）和S₁上关节突顶点间距（b），计算两者比值c（c=a/b），统计分析2组c值差异。结果 应力骨折组患者c值高于对照组，2组比较差异具有统计学意义（P<0.05）。结论 青年男性L₅峡部应力骨折患者其L₅上关节突间距增宽，S₁上关节突间距相对较小，该解剖特点可能与峡部应力骨折的发生相关。     

高低位腰椎椎间盘突出症患者脊柱-骨盆矢状面形态变化

目的 比较高位与低位腰椎椎间盘突出症（LDH）患者脊柱-骨盆矢状面形态学差异，探讨脊柱-骨盆矢状面形态学参数异常与高位LDH发生的关系。方法 纳入2006年1月—2022年1月收治的高位LDH患者53例（高位组），同时期性别、年龄和体质量指数（MBI）匹配的低位LDH患者53例（低位组）及单纯下腰部疼痛的非LDH患者53例（对照组）。在站立位全脊柱侧位X线片上测量3组矢状面平衡（SVA）、胸椎后凸角（TK）、腰椎前凸角（LL）、腰骶前凸角（LSL）、骶骨倾斜角（ST）、骨盆入射角（PI）、骨盆倾斜角（PT）、骶骨倾斜角（SS）等脊柱-骨盆矢状面参数。结果 高位组SVA、TK明显高于对照组，LL、ST、PI、PT及SS明显低于对照组；高位组TK明显高于低位组，LL、ST及PI明显低于低位组；差异均有统计学意义（P<0.05）。高位组L₁/L₂节段患者的LL、ST较L₂/L₃节段患者有下降趋势，但差异无统计学意义（P>0.05）。结论 骨盆水平化导致的胸腰段过度代偿可能是高位LDH发生、发展的机制之一。     

椎间盘造影中碘海醇剂量对大鼠椎间盘退行性变的影响

目的 探讨椎间盘造影中造影剂碘海醇剂量对椎间盘退行性变的影响。方法 以10只成年雄性SD大鼠的40个尾椎椎间盘（每只4个）为实验对象,分为空白组（Co₆/Co₇）、对照组（Co₇/Co₈）、常规剂量组（Co₈/Co₉,2 μL碘海醇）和高剂量组（Co₉/Co₁₀,3 μL碘海醇）。分别于椎间盘造影术后2周和4周使用X线检测椎间高度指数（DHI）,使用MRI评估椎间盘信号;术后4周检测椎间盘含水量,并采用HE染色检测组织学变化。结果 术后2周和4周时,与空白组相比,对照组DHI未见明显变化,常规剂量组和高剂量组DHI降低,且高剂量组比常规剂量组降低更为显著,差异均有统计学意义（P < 0.05）;对照组、常规剂量组和高剂量组椎间盘信号均降低,且剂量越大信号越低,差异均有统计学意义（P < 0.05）。与空白组相比,对照组椎间盘含水量未见明显变化,常规剂量组和高剂量组椎间盘含水量降低,且高剂量组降低更为显著,差异均有统计学意义（P < 0.05）。与空白组相比,对照组椎间盘组织学评分无明显变化,常规剂量组和高剂量组椎间盘组织学评分均增高,且剂量越大评分越高,差异均有统计学意义（P < 0.05）。结论 椎间盘造影时注入碘海醇可促进椎间盘退行性变,且呈剂量依赖性。在造影操作时应尽量减少造影剂的使用,以降低对椎间盘的影响。     

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.     

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.     

Immunomodulation in Transplantation with Photopheresis

Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.