关节镜下自体腘绳肌腱重建前交叉韧带

目的探讨关节镜下应用自体腘绳肌腱重建前交叉韧带(ACL)的临床疗效。方法在关节镜下采用4股自体腘绳肌腱、Endobutton钢板联合可吸收界面螺钉重建ACL治疗28例ACL损伤患者。结果 26例获得随访,时间4～20(12±2.3)个月。术后膝关节功能均在正常范围内,Lachman试验阴性23例,阳性3例(但终末点均"硬");Lysholm评分:术前为28～65(35.2±12.53)分,术后为90～98(93.12±5.10)分。结论关节镜下应用自体腘绳肌腱重建ACL创伤小,手术操作简便,效果可靠。     

关节镜下自体腘绳肌腱及横穿钉固定治疗前交叉韧带断裂

目的探讨关节镜下应用自体腘绳肌腱及横穿钉固定重建前交叉韧带（ACL）的临床疗效。方法对21例ACL断裂患者,采用自体4股腘绳肌腱、2枚可吸收股骨横穿钉（Rigidfix）联合可吸收界面螺钉关节镜下重建ACL。对患者进行Lysholm评分。结果 20例获得随访,时间12~36（15±2.3）个月。Lysholm评分：术前为43~65（51.2±1.75）分,术后提高到75~98（89.7±1.7）分。优13例,良5例,一般2例。结论关节镜下应用自体腘绳肌腱及横穿钉固定重建ACL具有疗效确切、创伤小、患者康复快等优点。     

Rigidfix与Intrafix螺钉在前交叉韧带重建中的应用

目的探讨关节镜下应用可吸收Rigidfix横穿钉与Intrafix膨胀挤压螺钉固定4股单束自体腘绳肌腱,重建前交叉韧带(anterior cruciate ligament,ACL)的手术方法和临床疗效。方法 2009年7月至2012年7月芜湖市中医院关节二科共诊治45例ACL损伤患者,取自体腘绳肌腱4股单束在关节镜下使用Intrafix膨胀挤压螺钉固定胫骨端,Rigidfix横穿钉固定股骨端,重建ACL。观察术后膝关节的稳定性及疗效。结果本组45例患者术后均得到随访,随访12~48个月,平均32个月。关节功能良好,Lysholm评分术前(42.30±4.20)分,术后12个月(92.54±2.10)分,术后评分明显提高,差异有统计学意义(P0.01)。结论关节镜下使用可吸收Rigidfix横穿钉与Intrafix膨胀挤压螺钉固定4股单束自体腘绳肌腱重建ACL,疗效肯定,操作简单,能够提供早期的初始稳定性和后期的生物稳定性,适宜基层医院临床应用推广。     

关节镜下可吸收螺钉固定腘绳肌重建前交叉韧带疗效评价

目的评价关节镜下可吸收螺钉固定腘绳肌腱重建膝关节前交叉韧带(ACL)的效果。方法27例患者(27膝)经关节镜检查证实均为ACL断裂,采用关节镜下自体腘绳肌重建ACL,生物可吸收螺钉解剖位固定重建韧带。结果所有病例均得到随访,时间6~24个月,均无术中、术后并发症,切口均一期愈合。IKDC综合评定:术前异常10例、严重异常17例,术后正常9例、接近正常16例、异常2例。Lysholm膝关节功能评分:由术前33~60分(平均45.7分)提高至83~96分(平均90.3分),差异有显著性(P<0.05)。结论关节镜下可吸收螺钉固定自体腘绳肌腱重建ACL手术创伤小、固定确实、操作简捷,近期疗效满意。     

关节镜下自体四股腘绳肌腱可吸收界面螺钉重建前交叉韧带

目的探讨自体四股绳肌腱、可吸收界面螺钉重建前交叉韧带(anteriorcruciateligament,ACL)的手术方法及疗效。方法关节镜下以自体四股绳肌腱为ACL重建替代物,保留少许ACL残端作为定位标志物,应用可吸收界面螺钉固定,对37例ACL损伤病例行重建术。结果随访6～28个月,平均11.4个月。术后36例膝关节活动度在正常范围,无韧带撞击现象。Lachman试验:33例≤1 ,4例2 。轴移试验术后全部阴性。Lysholm评分由术前的平均50.1分提高到术后的平均90.5分,差异有显著性意义(P<0.05)。结论关节镜下自体四股绳肌腱、可吸收界面螺钉重建ACL是恢复膝关节稳定性较好的方法。准确的关节内入口定位是手术成功的关键。     

关节镜下重建前交叉韧带时可吸收界面螺钉股骨隧道内口固定技术探讨

目的:探讨运用自体4股腘绳肌腱重建前交叉韧带(anterior cruciate ligament,ACL)时,磷酸三钙/聚乳酸(TCP/PLA)可吸收界面螺钉股骨隧道固定的有效方法,评价其临床疗效。方法:ACL损伤需行重建手术的患者27例,男18例,女9例;年龄21~48岁,平均34.5岁;左膝19例,右膝8例。所有患者均以4股自体腘绳肌腱为重建移植物,关节镜下以TCP/PLA可吸收界面螺钉固定股骨隧道,intrafix系统固定胫骨隧道重建ACL。术中注意股骨隧道周围的残端清理,过屈膝关节110°~120°,以使拧入可吸收界面螺钉与股骨隧道轴平行。达到坚强的内口固定。结果:27例中5例发生初次挤压失败。挤压螺钉螺母碎裂1例,隧道内脱空1例,脱空进入关节腔内3例。5例患者均进行挽救治疗后重新固定成功。27例患者均获得随访,随访时间10~18个月,平均14个月。Lachman试验:阴性14例;阳性Ⅰ度10例,阳性Ⅱ度3例。按Lysholm功能评分标准评估膝关节功能,术前平均为(53.1±3.9)分,终末随访时平均(93.3±3.1)分,差异有显著性统计学意义(P<0.05)。结论:关节镜下TCP/PLA可吸收界面螺钉隧道内口固定、4股腘绳肌腱重建ACL能良好地恢复膝关节功能。掌握界面螺钉挤入股骨隧道内口的角度是移植物股骨隧道内固定的关键。     

关节镜下应用EndoPearl和Intrafix固定腘绳肌肌腱重建前交叉韧带

目的 关节镜下采用腘绳肌肌腱和EndoPearl与Intrafix重建前交叉韧带.方法 31例前交叉韧带断裂患者在关节镜下采用四股腘绳肌肌腱重建前交叉韧带,股骨端应用EndoPearl和可吸收界面螺钉固定,胫骨端应用Intrafix固定,术后系统康复.结果 全部获随访,平均15.5个月(12～20个月).术前Lysholm评分平均为(54.2±5.4)分,术后为(98.4±0.2)分.与术前相比差异有显著性意义(P＜0.05).结论 关节镜下采用腘绳肌肌腱和EndoPearl与Intrafix重建前交叉韧带操作简单,固定可靠,疗效肯定.     

关节镜下自体腘绳肌腱重建膝关节前交叉韧带

目的：探讨关节镜下自体4股腘绳肌腱、生物可吸收挤压螺钉固定重建前交叉韧带（ACL）的临床效果。方法：31例经关节镜检查证实为前交叉韧带断裂的患者，男27例，女4例；年龄17～40岁，平均25岁。其中合并半月板损伤26例，合并局部软骨损伤3例，软骨Ⅰ～Ⅱ度退变16例。均于关节镜下行自体4股腘绳肌腱和软组织生物可吸收挤压固定螺钉重建ACL。术后对膝关节功能进行评定。结果：31例术后均未发生关节感染、血管神经损伤等严重并发症。30例获得随访，时间9-39个月，平均（19±9．0）个月，Lysholm膝关节功能评分从术前平均（54．6±16．6）分提高至随访时平均（92．5±5．7）分，较术前显著改善（t=11．84，P〈0．01）。30例患者中，26例恢复伤前运动水平，2例运动水平较伤前降低，2例因运动后出现关节酸痛而不敢剧烈运动。结论：关节镜下采用4股腘绳肌腱作移植物，生物可吸收挤压螺钉固定，是重建ACL的一种安全可靠的治疗方法。具有手术创伤少、术后膝关节功能恢复良好的优点。     

双束双隧道6股腘绳肌腱解剖重建前交叉韧带

目的探讨双束双隧道6股腘绳肌腱重建前交叉韧带（ACL）的可行性及近期疗效。方法对28例ACL损伤患者行关节镜下ACL重建术。采用股骨胫骨双隧道建立前内侧束（AMB）及后外侧束（PLB）。分别将股薄肌腱、半腱肌腱编织成3股肌腱,用于重建PLB与AMB。AMB与PLB股骨端均用Endobutton钢板固定,胫骨端AMB用Bio-Intrafix固定,PLB用Milagro可吸收界面螺钉固定。结果 28例均获随访,时间12-24（19.54±3.84）个月。根据Lysholm膝关节功能评分：术前为18-60（34.79±12.53）分,术后1年为90-98（95.54±2.06）分,差异有统计学意议（t=26.51,P〈0.01）。结论双束双隧道6股腘绳肌腱重建ACL,手术操作简便,固定牢固,效果可靠。     

关节镜下股骨双隧道双束腘绳肌肌腱重建后十字韧带

目的探讨关节镜下采用可吸收界面螺钉固定双束腘绳肌肌腱,股骨双隧道重建后十字韧带(PCL)的方法和疗效。方法24例PCL损伤患者,年龄为17￣42岁,平均32岁。在关节镜下应用可吸收界面螺钉固定,股骨双隧道胫骨单隧道双束腘绳肌肌腱重建PCL。3股半腱肌肌腱在屈膝15°￣30°位拉紧、固定,重建前外侧束;3股股薄肌肌腱在屈膝60°￣70°位拉紧、固定,重建后内侧束。结果24例患者术后随访6￣19个月,平均9.4个月。术后膝关节活动度均在正常范围,无疼痛,无创伤性关节炎。后抽屉试验、反向Lachman试验、胫骨结节塌陷征和反向轴移试验均为阴性,术后Lysholm评分为(92.7±6.4)分,较术前(49.4±9.3)分有显著提高(t=3.12,P<0.01)。术后Tegner活动评分为(6.7±1.4)分,较术前(3.2±0.9)分有显著提高(t=3.13,P<0.01)。结论股骨双隧道胫骨单隧道双束自体腘绳肌肌腱重建PCL能够较好的重建膝关节在不同伸屈角度的稳定性。生物可降解螺钉为PCL重建的理想的内固定材料。     

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 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.     

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.     

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.     

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.