小切口复位空心钉内固定治疗跟骨骨折

目的探讨经距下关节小切口撬拨复位植骨结合经皮空心钉内固定治疗SandersⅡ、Ⅲ型跟骨关节内骨折的疗效。方法采用跟骨外侧距下关节小切口撬拨复位后植入同种异体骨+经皮空心螺钉内固定治疗35例SandersⅡ、Ⅲ型跟骨骨折患者。测量术前术后Bhler角和Gissane角的变化,根据角度变化数值观察关节面恢复情况。结果 35例均获随访,时间10～32(14±3.5)个月,患者骨折均愈合。未出现切口感染、皮瓣坏死、腓肠神经损伤等并发症。按Maryland足部评分标准评价手术效果:优23例,良9例,可2例,差1例,优良率达91.4%。结论距下关节小切口复位、植骨、经皮空心螺钉内固定治疗SandersⅡ、Ⅲ型跟骨骨折,软组织损伤少、关节面复位好,疗效满意。     

跗骨窦小切口微创经皮钢板内固定治疗Sanders Ⅲ、 Ⅳ型跟骨关节内骨折的疗效分析

目的 探讨跗骨窦小切口微创经皮钢板内固定（minimally invasive percutaneous plate osteosynthesis, MIPPO）技术治疗Sanders Ⅲ、Ⅳ型跟骨关节内骨折的临床疗效。方法 回顾性分析2018年1月至2018年12月我院通过跗骨窦小切口MIPPO技术治疗的32例Sanders Ⅲ、Ⅳ型跟骨关节内骨折病人的临床资料,其中男22例,女10例,年龄为（39.29±9.75）岁。致伤原因：高处坠落26例,交通事故伤6例。Sanders Ⅲ型21例,Sanders Ⅳ型11例。比较术前、术后即刻及术后1年三个时间点的Böhler角及Gissane角,应用Maryland足功能评分评价术后功能。结果 所有病人均于伤后3~5 d完成手术,未见软组织并发症。术后即刻Böhler角为32.54°±2.76°,Gissane角为121.56°±4.98°;术后1年Böhler角为31.72°±2.54°,Gissane角为120.50°±6.03°,术后即刻及术后1年的Böhler角及Gissane角均较术前明显改善（P均＜0.05）,术后1年Maryland足功能评分为（78.69±6.19）分。结论 跗骨窦小切口MIPPO技术是治疗Sanders Ⅲ、Ⅳ型跟骨关节内骨折的有效办法,临床疗效满意。     

撬拨复位拉力螺钉内固定与小切口复位接骨板内固定治疗跟骨骨折的病例对照研究

目的:比较单纯撬拨复位拉力螺钉内固定与小切口复位接骨板内固定治疗跟骨骨折的临床疗效。方法 :回顾性分析2015年6月至2018年6月收治的88例(98足)跟骨骨折患者的临床资料。根据骨折分型及治疗方法不同分为撬拨复位拉力螺钉内固定术组(A组)50例,男32例,女18例;年龄(32.6±6.7)岁;SandersⅡ-Ⅲ型30例,SandersⅣ型20例。小切口复位接骨板内固定术组(B组)48例,男30例,女18例;年龄(31.9±7.2)岁;SandersⅡ-Ⅲ型28例,SandersⅣ型20例。分别于术前、术后1个月及1年比较两组患者的B觟hler角、Gissane角及AOFAS评分以评价其临床疗效。结果:所有患者获得随访,时间13～24(14.6±6.3)个月。术后两组B觟hler角、Gissane角及AOFAS评分均得到不同程度改善。对于SandersⅡ-Ⅲ型患者,两组术前、术后1个月及1年B觟hler角、Gissane角比较差异无统计学意义;术后1年AOFAS评分比较差异无统计学意义。对于SandersⅣ型患者,B组术后1个月、1年时B觟hler角[(35.40±1.85)°、(35.15±1.90)°]和Gissane角[(127.80±5.49)°、(127.00±3.06)°]高于A组B觟hler角[(27.85±3.42)°、(27.25±1.80)°]和Gissane角[(118.00±4.13)°、(117.50±5.04)°](P0.05);两组术后1个月、1年时B觟hler角、Gissane角均较术前提高(P0.05); B组术后1年AOFAS评分91.00±5.46高于A组84.50±4.64(P0.05)。结论:对于SandersⅡ-Ⅲ型中度跟骨骨折,两种治疗方法疗效相当;但对于SandersⅣ型重度跟骨骨折,与撬拨复位拉力螺钉内固定术相比,小切口复位接骨板内固定术可获得更好的复位和可靠固定,改善患足功能。     

老年跟骨关节内移位骨折的手术治疗

目的：观察老年跟骨关节内移位骨折手术治疗的临床疗效,探讨其手术指征。方法：2000年1月至2007年12月,切开复位内固定治疗老年跟骨关节内移位骨折24例26足,男18例18足,女6例8足;年龄60～75岁,平均67岁。按Sanders分型,Ⅱ型13足,Ⅲ型12足,Ⅳ型1足。术前和术后测量跟骨结节关节角(B?hler角)和跟骨交叉角(Gissane角).采用Maryland足部评分系统评分。结果：24例26足均获得随访,时间12～26个月,平均18.4个月。B?hler角术前平均(10.4±8.2)°,术后平均(27.8±7.4)°;Gissane角术前平均(136.5±10.3)°,术后平均(124.3±4.2)°;手术前后差异均有统计学意义(P<0.05).患足功能优5 足,良16 足,中4足,差1足。术后12足出现并发症,其中3足皮肤坏死,2足创口感染,1足腓肠神经损伤和6足创伤性距下关节炎。结论：老年跟骨关节内移位骨折患者经手术治疗均能取得较好的临床效果。只要全身情况允许,老年跟骨关节内移位骨折应行切开复位内固定治疗。     

经皮撬拨复位空心钉内固定治疗Sanders Ⅱ、Ⅲ型跟骨骨折

[目的]评估经皮撬拨复位空心钉内固定治疗SandersⅡ型及Ⅲ型跟骨骨折的疗效。[方法]回顾分析2011年12月~2015年2月收治并获得随访的移位的跟骨关节内骨折患者23例(23足),其中男20例(20足),女3例(3足);年龄18~70岁,平均38.4岁。左侧14足,右侧9足;开放性骨折2例(2足),闭合性骨折21例(21足)。根据跟骨骨折Sanders分型:Ⅱ型13例,Ⅲ型10例。手术均采用经皮斯氏针撬拨复位空心螺钉内固定治疗。术后定期拍摄X线片明确骨折愈合情况,测量Bhler角和Gissane角。采用美国足踝外科协会(American Orthopaedic Foot and Ankle Society,AOFAS)踝与后足评分标准评价患足功能。[结果]23例患者均获得随访,时间12~47个月,平均22.8个月。术后无针道感染和骨髓炎发生。所有患者均获得骨性愈合,愈合时间8~14周,平均10.4周。末次随访时患者Bhler角和Gissane角分别为(29.35±1.67)°和(121.83±4.45)°,与术前的(15.17±4.39)°和(100.57±6.95)°比较,差异均有统计学意义(t=18.810,P0.001;t=12.396,P0.001)。末次随访时AOFAS踝与后足评分为58~100分,平均86.4分,其中优12例、良8例、可2例、差1例,优良率86.96%(20/23)。1例SandersⅢ型骨折术后6周复位丢失,6个月后并发距下关节创伤性关节炎。[结论]SandersⅡ型跟骨骨折最适宜闭合撬拨复位空心螺钉固定,SandersⅢ型骨折若移位的骨折块比较大,且术者能充分领悟骨折的移位机制和三维空间位置,通过撬拨也能够较好的实现复位,方法微创,固定可靠,并发症少。     

经跗骨窦间隙与外侧“L”形切口治疗SandersⅡ型跟骨骨折的疗效比较

 目的 评估经跗骨窦间隙有限切开及传统切开复位内固定治疗SandersⅡ型跟骨关节内骨折的近期疗效。方法 2010年2月至2011年2月,筛选30例患者纳入研究,并随机分为微创组及切开组,每组15例。微创组采用经跗骨窦间隙有限切开复位内固定,切开组采用“L”形外侧扩大切口行切开复位内固定。术后拍摄X线片明确骨折愈合情况,测量B?hler角和Gissane角,记录相关并发症。采用视觉模拟评分(visual analogue scale, VAS)、美国足踝外科协会(American Orthopaedic Foot and Ankle Society, AOFAS)踝与后足评分系统及简明健康状况调查表(SF-36)综合评估最终疗效。结果 微创组及切开组平均随访时间分别为16.9个月和19.9个月。切开组有2例发生皮肤切缘表皮坏死。两组病例均在术后3个月骨折愈合。术后微创组B?hler角平均13.1°±3.8°,Gissane角平均28.1°±7.8°;切开组B?hler角平均14.9°±4.3°,Gissane角平均26.2°±8.2°。末次随访时,微创组AOFAS和VAS评分分别为(91.2±15.9)分和(1.7±1.3)分;切开组分别为(82.4±14.7)分和(1.9±2.1)分;SF-36评分微创组［(79.5±12.1)分］优于切开组［(70.2±12.4)分］。微创组4例、切开组15例出现不同程度距下关节僵硬。结论 治疗SandersⅡ型跟骨关节内骨折,两种方法近期疗效无明显差异,但采用经跗骨窦间隙有限切开术后软组织并发症发生率及距下关节僵硬率低。     

累及距下关节跟骨骨折的手术治疗

目的　探讨使用开放复位“Y”形钛钢板内固定治疗累及距下关节跟骨骨折的效果。方法　自 1 998年 7月～ 2 0 0 3年 8月 ,使用开放复位“Y”形钛钢板内固定治疗累及距下关节跟骨骨折 1 8例 2 0侧 ,比较手术前后B hler角、Gissane角、跟骨长度、宽度及高度。结果　术后经平均 1 0 6个月随访 ,所有病人均恢复正常行走 ,足弓恢复正常 ,B hler角由术前平均 - 6 2 5°恢复至术后平均 1 9 35°,跟骨丘部高度由术前 36 4 0mm恢复至术后 4 2 90mm。结论　对于累及距下关节跟骨骨折行切开复位“Y”形钛钢板固定 ,即可复位距下关节 ,恢复B hler角、Gissane角 ,同时又可恢复跟骨的长度、高度及宽度 ,使其达到解剖复位 ,病人能早期进行功能锻炼 ,是较好的治疗方法     

距下关节镜下克氏针空心螺钉内固定治疗跟骨骨折

目的探讨距下关节镜下克氏针空心螺钉内固定治疗跟骨骨折的优缺点及疗效。方法 2015年8月至2016年8月,采用距下关节镜下克氏针空心螺钉内固定治疗跟骨骨折16例,男11例,女5例;年龄23~54岁,平均31.5岁。骨折按Sanders分型,Ⅱ型9例(ⅡA型3例,ⅡB型5例,ⅡC型1例),Ⅲ型7例(ⅢA型2例,ⅢB型5例)。根据美国足踝外科协会(American orthopaedic foot and ankle society,AOFAS)踝-后足评分评价效果,并记录相关并发症。结果 16例中有1例因关节面中央塌陷而改切开复位内固定,其余均顺利结束手术。术前B9hler角(16.4±3.7)°,Gissane角(107.3±9.2)°,跟骨宽度(37.8±2.6)mm;术后B9hler角(24.1±2.4)°,Gissane角(117.3±7.2)°,跟骨宽度(33.2±1.2)mm。术后4例失访,12例获得5~24个月随访,平均随访17个月,X线片示12足均获得解剖复位,足弓形态恢复正常。所有患者无皮肤、软组织并发症发生。末次随访时AOFAS评分平均86.3分,结果优6例,良4例,可2例,优良率为83.33%。结论采用距下关节镜下克氏针空心螺钉内固定治疗跟骨骨折与传统术式相比显示了微创的优势,能获得满意的治疗效果。     

闭合复位Herbert螺钉内固定治疗跟骨骨折

目的探讨闭合复位Herbert螺钉内固定治疗跟骨骨折的疗效。方法采用闭合复位Herbert螺钉内固定治疗20例跟骨骨折患者。结果患者均获得随访,时间6~12个月。患者骨折均愈合,无伤口并发症。跟骨Bhler角由术前5.2°±3.7°恢复至末次随访时的20.4°±2.8°,差异有统计学意义(t=-17.16,P0.01);Gissane角由术前92.9°±4.8°恢复至末次随访时的122.5°±4.4°,差异有统计学意义(t=-10.84,P0.01)。Maryland足部评分:优10例,良8例,可2例。结论闭合复位Herbert螺钉内固定治疗SandersⅡ型跟骨骨折和跟骨结节横形骨折临床效果满意。     

经皮微创撬拨复位空心钉内固定治疗跟骨骨折疗效分析

目的 :探讨经皮微创撬拨复位空心钉内固定治疗跟骨骨折SandersⅡ、Ⅲ型的治疗效果。方法 :选择自2012年1月至2014年1月期间采用经皮微创撬拨复位空心钉内固定治疗19例SandersⅡ、Ⅲ型跟骨骨折患者,男14例,女5例;年龄19~58岁,平均(38.3±4.1)岁。测量术前后B觟hler角和Gissane角的变化,根据角度变化,观察关节面恢复情况,并按照Maryland足部评分标准评价手术效果。结果:19例均获随访,随访时间(22.3±5.3)个月。术后B觟hler角和Gissane角较术前改善(P0.05)。Maryland评分83.2±8.4。结论 :经皮微创撬拨复位空心钉内固定治疗跟骨骨折疗效满意,损伤小,并发症少,术后恢复快,缩短住院时间,是跟骨SandersⅡ、Ⅲ型骨折的有效治疗方法之一。     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

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.     

Membranes in Artificial Organs

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.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.     

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.