单螺纹和双螺纹椎弓根螺钉抗拔出力比较的临床研究

背景:椎弓根螺钉技术是目前脊柱固定融合最常用的方法。为减少螺钉松动和拔出等并发症,研究人员在螺钉设计等方面进行了不断探索。目的目的:比较单螺纹和双螺纹椎弓根螺钉应用于腰椎内固定术时的螺钉抗拔出力。方法方法:78例行腰椎椎弓根螺钉固定术的患者随机分为两组,所有患者术前均测量髋部骨密度和腰椎骨密度。一组在术中植入单螺纹椎弓根螺钉,另一组则植入双螺纹椎弓根螺钉,测量拧入每枚螺钉时的最大扭矩(以下简称"螺钉扭矩"),比较两组患者的骨密度和螺钉扭矩。结果结果:单螺纹螺钉组患者40例,术前髋部骨密度T值-1.82±0.57,腰椎骨密度T值-2.17±0.77,术中共植入单螺纹椎弓根螺钉150枚,螺钉扭矩(1.03±0.39)Nm。双螺纹螺钉组患者38例,术前髋部骨密度T值-1.90±0.62,腰椎骨密度T值-2.34±0.81,共植入双螺纹椎弓根螺钉150枚,螺钉扭矩(1.45±0.39)Nm。两组患者术前骨密度无明显差异(P>0.05),双螺纹螺钉组的螺钉扭矩显著高于单螺纹螺钉组(P<0.001)。结论结论:相较于单螺纹椎弓根螺钉,双螺纹椎弓根螺钉应用于腰椎内固定术可增加螺钉的抗拔出力。     

膨胀式椎弓根螺钉抗旋出性能的生物力学测试

目的:测试并比较自行设计的膨胀式椎弓根螺钉(Expansive Pedicle Screw,EPS)与USS,Tenor,CDH椎弓根螺钉植入椎体后的最大旋出力矩及旋出180°时能量吸收值,评价EPS螺钉脊柱固定稳定性.方法:30个新鲜小牛腰椎随机分成3组,每组10个椎体(20侧椎弓根),每组均随机在一侧拧入EPS螺钉,对侧分别拧入USS、Tenor,CDH螺钉,旋出螺钉,测试并记录最大旋出扭力矩及旋出180°时能量吸收值.结果:EPS,USS,Tenor,CDH螺钉的最大旋出力矩分别为(3.570±0.914)Nm,(1.607±0.300)Nm,(2.257±0.372)Nm,(2.371±0.348)Nm;能量吸收值分别为(8.277±2.108)J,(3.230±0.559)J,(4.475±0.602)J,(4.441±0.457)J.EPS螺钉的最大旋出力矩及能量吸收值显著大于其它三种螺钉(P值均小于0.01).结论:EPS螺钉较目前使用的USS,Tenor,CDH非膨胀椎弓根螺钉有更好的固定稳定性.     

改良通用脊柱内固定系统治疗生长发育期脊柱畸形209例报告

[目的]研制改装通用脊柱内固定系统(USS)为两端滑动中段锁定横连杆套式滑动的椎弓根螺钉固定框架结构,经后路手术治疗生长发育期脊柱畸形。[方法]自2000年6月~2006年6月使用改装USS系统内固定治疗生长发育期脊柱畸形209例。男106例,女103例,其中特发性脊柱侧弯92例,先天性脊柱侧弯72例,青年驼背26例,其他19例。年龄:女8~14岁,男10~16岁,平均13.22岁。改装USS系统后路顶椎为中心3~5椎节置锁定螺钉,其余两端椎节均为滑动螺钉。双横连杆与矫形棒连接处为锁定结构、协同固定矫形棒、而横连杆连接处为套管式滑动。这种改装的USS系统不影响脊柱的纵向生长和两椎弓根的横向间发育。[结果]本组209例,术后26~60个月随访96例。畸形度数Cobbs角45°~110°,平均Cobbs角68°,术中矫形脊柱增高4~15cm,平均7cm,平均增高2.4cm。断棒3例,但无移位及神经症状。[结论]改装USS系统的两端滑动中段锁定椎弓根螺钉框架后路手术固定矫形保留中段锁定不失原有的三维矫形力度、矫形力量强度、钢度。两端滑动不限制脊柱继续生长,滑动的横连杆不限制椎弓根间横向发育,术后26~60个月随访观察疗效满意。     

滑动椎弓根钉棒系统治疗生长发育期特发性脊柱侧弯

[目的]应用一种中间锁定两端滑动的椎弓根钉棒系统治疗生长发育期特发性脊柱侧弯。[方法]采用中间锁定两端滑动椎弓根螺钉系统治疗生长发育期特发性脊柱侧弯66例。手术在全麻下进行,侧弯主弯区(顶椎)两个椎体两侧置入4枚椎弓根钉,在顶椎两端上下椎体每间隔1个椎体置入滑动钉,平均每一侧置入4～6枚椎弓根螺钉。选择2根矫形合金棒置入椎弓根钉尾端,两端多出上下末位钉约3 cm,留出纵向滑移的空间,折成生理弧度,H型套帽固定尾部,然后慢慢旋转双棒,矫正脊柱畸形,将双棒锁紧固定于主弯区顶椎4枚钉上,在双侧矫形棒上放置横向滑动或锁定连杆,并锁紧,框架结构固定完毕。[结果] 66例特发性脊柱侧弯术前Cobb角(53.16±3.44)°,术后为(8.23±2.01)°,手术矫形效果满意。术前Cobb角≤50°患者矫正率为85%,术后随访1～6年,滑动区域内螺钉随脊柱纵向生长而伴发的生长性滑移距离1.5～3 cm,全部患者随访未见断钉、断棒和神经损伤等严重并发症。[结论]中间锁定两端滑动的椎弓根钉棒系统治疗生长发育期特发性脊柱侧弯过程中不影响患者正常发育且固定牢固。     

通用型脊柱内固定系统椎弓根螺钉的生物力学测试

目的测试自行设计的通用型脊柱内固定系统(generalspinesystem,GSS)椎弓根螺钉以及SOCON和CCD螺钉置入正常成人椎体标本的最大轴向拔出力及最大旋入力矩,评价GSS螺钉对椎弓根的锚固作用。方法将27个正常成人腰椎椎体标本随机分为3组,每组9个椎体(18侧椎弓根),分别置入GSS、SOCON和CCD椎弓根螺钉,行螺钉拔出试验,测试并记录螺钉的最大旋入力矩和最大轴向拔出力。结果三组螺钉的最大旋入力矩分别为(1.83±0.27)Nm、(2.09±0.51)Nm和(1.66±0.34)Nm,最大轴向拔出力分别为(1131.0±255.4)N、(1034.0±262.3)N和(886.1±152.9)N。GSS螺钉最大轴向拔出力最大,且与CCD螺钉相比差异有非常显著性意义(P<0.01)。结论GSS螺钉具有很强的椎弓根锚固作用。     

腰椎横突间入路椎体间融合术的生物力学评价

目的 观察腰椎横突间入路椎体间融合术(ILIF)及附加椎弓根钉固定后的生物力学稳定性.方法 采用小牛脊柱运动节段标本12具,依序进行不同处理后分为以下7组:(1)正常对照组(IS);(2)左侧小关节切除+椎间融合器植入组(TLIF);(3)TLIF附加同侧椎弓根钉固定组;(4)TLIF附加双侧椎弓根钉固定组;(5)左侧横突间入路椎间融合器植入组(ILIF);(6)ILIF附加同侧椎弓根钉固定组;(7)ILIF附加双侧椎弓根钉固定组.分别测试各组在轴向压缩、前屈、后伸、左右侧屈时的载荷-应变、载荷-位移变化以及轴向刚度和双向扭转稳定性等生物力学指标,并进行统计学比较.结果 所有生物力学指标中ILIF组稳定性均大于TLIF组(P<0.05),在定量扭矩扭角方面差距最大达72%.ILIF+BPSF的稳定性最高,在前屈载荷应变方面较IS组差异最大达53%,而ILIF+HPSF组与ILIF+BPSF组比较差异无统计学意义(P>0.05). 结论 ILIF手术生物力学稳定性优于TLIF手术;ILIF附加同侧椎弓根钉固定与附加双侧椎弓根钉固定生物力学稳定性相当,使用ILIF术式附加侧同椎弓根螺钉固定,可提供较好的即刻稳定性.     

MPR-CT个体化重建技术在脊柱侧凸术中的应用

目的评价在脊柱侧凸术中应用多平面重建(MPR)-CT技术的价值。方法比较应用MPR-CT个体化重建技术在脊柱侧凸患者中椎弓根螺钉植入的准确性。38例患者分为2组:MPR-CT组20例,对照组18例。两组术前平均Cobbs角分别为58.6°±20.4°和54.3°±19.8°。MPR-CT组术前进行单椎体椎弓根平面扫描重建,评价椎弓根的旋转角度、适宜进钉点、进钉长度、矢状位倾斜角度。术中均采用徒手椎弓根穿刺技术记录术中一次性椎弓根穿刺成功率。术后根据CT检查评估椎弓根螺钉植入位置,穿孔螺钉测量与理想进钉角度差。X线评价术后Cobb角和矫正率。结果术后Cobb角:MPR-CT组为18.7°±13.6°,对照组为19.3°±14.2°,矫正率分别为68.1%和64.4%。椎弓根一次穿刺成功率:MPR-CT组为91.2%,对照组为85.4%。穿孔率:MPR-CT组为4.5%,对照组为9.3%。穿孔螺钉测量较理想进钉角度差:MPR-CT组为7.2°±5.1°,对照组为9.2°±4.9°。两组年龄、术前、术后Cobb角、矫正率差异无统计学意义(P0.05)。在一次性穿刺成功率、螺钉穿破率及穿孔螺钉测量较理想进针角度差异有统计学意义(P0.05)。38例均未出现血管和脊髓损伤等并发症。结论脊柱侧凸患者的椎体旋转是重要的术前评估指标,术前MPR-CT检查可详细了解椎体旋转,减少椎弓根螺钉穿孔。     

滑动椎弓根钉系统稳定性体外生物力学测试

[目的]对滑动椎弓根钉系统(SPSS)与通用椎弓根钉系统(USS)在脊柱侧凸固定强度、刚度和稳定性等方面进行生物力学比较,以测试滑动椎弓根螺钉内固定系统稳定性的生物力学性能.[方法]采用12具猪新鲜脊柱标本,随机分成两组分别测量不同工况下T12椎体的位移,并计算其强度和刚度进行比较.[结果]滑动组和通用组无论在轴向压缩、前屈、后伸、侧屈情况下,主应变、位移变化及固定强度、刚度均无显著性差异(P>0.05).[结论]滑动椎弓根钉系统治疗脊柱侧凸同样能够达到通用椎弓根钉系统相同的矫形效果及生物力学稳定性,同时它不影响青少年生长发育.     

聚甲基丙烯酸甲酯强化对骨质疏松椎弓根螺钉固定的生物力学作用

目的探讨聚甲基丙烯酸甲酯 (polymethylmethacrylate,PMMA)骨水泥强化椎弓根螺钉的方法和评价 PMMA强化骨质疏松椎弓根螺钉后的生物力学性质。方法 6具新鲜老年女性胸腰段骨质疏松脊柱标本 (T10～ L5),使用双能 X线骨密度吸收仪测试每个椎体的骨密度,随机取 16个椎体 (32侧椎弓根 ),一侧椎弓根拧入 CCD螺钉,测量最大旋入力偶矩后拔出螺钉作为正常对照组,用 PMMA骨水泥强化椎弓根螺钉作为修复固定组,行螺钉拔出试验;另一侧经导孔直接强化椎弓根螺钉后拔出作为强化固定组,记录三组螺钉的最大轴向拔出力。结果椎体平均骨密度为 (0.445± 0.019)g/cm2;螺钉最大旋入力偶矩为（ 0.525± 0.104） Nm;正常对照组螺钉最大轴向拔出力为 (271.5± 57.3)N;修复固定组为 (765.9± 130.7)N;强化固定组为 (845.7± 105.0)N。 PMMA骨水泥强化或修复骨质疏松椎弓根螺钉后最大抗压力明显高于强化前,差异有非常显著性意义 (P< 0.01)。结论 PMMA骨水泥强化骨质疏松椎弓根螺钉能显著增加螺钉在椎体内的稳固性。     

新型经皮椎弓根螺钉系统的设计与生物力学测试

目的 评估新型经皮椎弓根螺钉系统设计的合理性和临床操作可行性.方法 取6具经甲醛处理的完整尸体标本,模拟临床手术操作安放新型经皮椎弓根螺钉系统(A组),以传统经皮椎弓根螺钉系统为对照(B组).应用新型经皮椎弓根螺钉系统在新鲜小牛腰椎压缩性骨折模型上行撑开操作.分别以单向螺钉、改良螺钉和万向螺钉跨节段固定骨折,测量固定节段的三维稳定性.结果 A组平均手术时间(38.2±6.20)min,B组(56.4±12.8)min,差异有统计学意义(P<0.05).A组螺钉位置优良率91.7%,B组95.8%,差异无统计学意义.新型椎弓根螺钉系统对三种螺钉均具有良好的撑开功能,改良螺钉和单向螺钉主要撑开椎体前柱,两者差异无统计学意义;万向螺钉主要撑开椎体中、后柱,对前柱撑开效果较其他两种螺钉差(P<0.05).三组固定节段在完整状态和骨折状态的屈伸、左右侧弯及旋转运动范围无统计学差异.改良螺钉和单向螺钉固定后固定节段有相似的三维稳定性;万向螺钉屈伸稳定性较改良螺钉差(P<0.05),而侧弯和旋转稳定性与其他两组接近.结论 改良螺钉能有效撑开椎体前柱,螺钉-棒系统可对固定节段提供稳定性.新型经皮椎弓根螺钉系统具有临床操作可行性.     

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.