关节镜下“微骨折”技术修复关节软骨缺损的临床研究

目的探讨关节镜下应用＂微骨折＂技术微创修复膝关节全层关节软骨缺损手术的效果。方法全层关节软骨缺损病例进行随机分组,一组作关节清理后应用＂微骨折＂技术进行修复（实验组）,另一组仅作关节清理（对照组）。结果本组68例均获随访,随访时间6～18个月,平均8.6个月。按Lysholm评分标准,对评分结果进行比较分析。术后近期随访,Lysholm评分实验组明显优于对照组。结论关节镜下应用＂微骨折＂技术修复全层关节软骨缺损,经近期随访,膝关节功能恢复较为满意。     

关节镜下应用微骨折方法修复关节软骨缺损的实验研究及临床初步应用

目的探讨应用微骨折技术对全层关节软骨缺损修复的效果。方法20只大白兔随机分为两组，在其右股骨内髁先建立全层软骨缺损模型，实验组进行微骨折处理，对照组则不予特殊处理。分别在4周和8周各处死10只实验兔，作大体观察、病理学检查和修复组织厚度测量。临床上对68例全层关节软骨缺损进行随机分组：实验组35例，关节清理后应用微骨折技术进行处理；对照组33例，仅作关节清理术。结果对照组只有肉芽组织和瘢痕组织生长，仅边缘有少量软骨组织生长，实验组在4周时大部分为软骨组织生长，8周已全部被软骨组织修复。术后平均随访8．6个月，Lysholm评分实验组明显优于对照组。结论微骨折技术是一种有效的修复全层关节软骨缺损方法。     

关节镜下微骨折术修复膝关节软骨缺损

目的探讨关节镜下微骨折术修复膝关节软骨缺损的效果。方法关节镜下微骨折术治疗膝关节股骨髁软骨缺损62例,其中股骨内髁软骨缺损34例,外髁软骨缺损28例,均为病状孤立、全层软骨损伤、关节稳定且有相应症状的患者。结果随访6个月～7年,按HSS评分评级:优良42例,可16例,差4例,术前和术后HSS评分比较,有显著增加(t=52.43,P<0.01)。结论关节镜下微骨折术修复膝关节软骨缺损在低年龄(45岁以下),低体重(体重指数低)患者中疗放显著,而对高龄肥胖患者疗效不佳。     

应用微骨折技术修复全层关节软骨缺损

关节软骨对关节功能及骨骺生长非常重要，关节软骨损伤临床并不少见，而软骨本身几乎没有自我修复能力，常常导致关节功能障碍。本实验旨在建立兔股骨内髁全层关节软骨缺损实验模型，利用微骨折技术修复软骨缺损。     

关节镜下应用“微骨折”技术修复膝关节软骨缺损的护理

目的：探讨关节镜下应用“微骨折”技术对膝关节全层关节软骨缺损修复的护理效果。方法：对68例全层关节软骨缺损的患者，采用关节清理后应用“微骨折”技术进行处理。手术后常规护理，实施预防感染及下肢静脉血栓等并发症护理措施，并分步骤地进行康复训练及出院指导。结果：术后随访6～18个月，平均8．6个月，患者关节疼痛显著减轻，关节功能改善。结论：术后给予科学的护理，正确的康复指导，获得满意疗效。     

关节镜下微骨折术和关节清理术修复膝关节软骨缺失临床疗效对比研究

目的比较关节镜下行微骨折术和关节清理术修复膝关节软骨缺失的临床疗效。方法笔者自2009-06—2013-07在关节镜下行微骨折术(微骨折术组)和关节清理术(关节清理组)治疗96例膝关节软骨缺损,比较2组术后治疗效果及并发症情况。结果 2组均获平均8(6~10)个月随访。微骨折术组术后Tegner和HSS评分均高于关节清理组,差异有统计学意义(P0.05),微骨折术组术后疼痛症状消失率和肿胀症状消失率均高于关节清理组,差异有统计学意义(P0.05),微骨折术组术后总有效率为94.2%,显著高于关节清理组的72.7%。结论关节镜下微骨折术治疗膝关节软骨缺损可有效改善术后膝关节功能,缓解临床症状。     

关节镜下关节清理扩创微骨折术后配合运动疗法治疗中老年膝骨关节炎临床疗效观察

膝骨关节炎是常见的退行性疾病,可造成关节疼痛、功能障碍,严重影响中老年人群的生活质量,膝关节骨性关节炎的病理核心是软骨缺损.因此通过关节镜下关节清理扩创微骨折(microfracture)技术修复膝关节软骨缺损.修复后软骨由纤维软骨所替代已被组织学证实[1].     

比较关节镜下微骨折术与关节清理术治疗膝关节软骨损伤的效果

目的比较关节镜下微骨折术与关节清理术治疗膝关节软骨损伤的效果。方法根据不同术式将68例膝关节软骨损伤患者分为2组,各34例。关节清理组给予关节镜下关节清理术,微骨折术组行关节镜下微骨折术。结果微骨折术组手术优良率、HSS评分及VAS评分均优于关节清理组,差异均有统计学意义(P0.05)。结论与关节清理术比较,关节镜下微骨折术更有利于缓解患者的疼痛和改善膝关节功能。     

关节软骨缺损修复方法及疗效

关节软骨缺损后自我修复能力很差,治疗方法如关节灌洗清理术、Pridie钻孔术、微骨折术、骨膜和软骨膜移植、骨软骨移植、细胞移植和组织工程化软骨修复等的疗效不一.骨软骨移植和细胞移植技术相对成熟且临床效果较好.组织工程化软骨修复是目前研究的热点且已逐步试用于临床,多重复合的仿生支架和携带细胞因子仍是研究重点,临床实际应用还有待观察.     

膝关节软骨损伤的外科治疗进展

关节软骨损伤后,软骨缺损通常缺乏自行修复能力,要求外科修复。传统外科治疗软骨损伤包括关节镜下冲洗清理术、微骨折术、自体骨软骨移植术、异体骨软骨移植术和自体软骨细胞移植等方法。关节冲洗清理术去除了关节内致痛因素,操作简单,应用广泛,早期疗效确切。微骨折术及自体骨软骨移植对小面积的软骨缺损修复较为理想,然而远期临床观察发现钻孔渗透修复的纤维软骨会降低微骨折术后疗效,相对于重建负重区关节面完整性自体骨软骨移植更具有优势。自体软骨细胞移植及异体骨软骨移植适用于更大面积的软骨缺损,异体骨软骨移植术后存活率受到局部排斥反应影响,从而降低了远期疗效。软骨组织工程技术可最大限度地提高自体软骨细胞移植的修复质量,实现修复组织接近透明软骨,但对于累及软骨下骨板、反应性骨水肿、严重骨量丢失或下肢轴线不良具有局限性。近年来许多新技术陆续应用于软骨损伤治疗领域,创伤小、操作简便、恢复快、疗效好、花费低、多技术联合应用的外科修复技术将会成为未来的治疗软骨损伤的重要手段。目前如何提高软骨修复质量,更具抗压、耐磨性,仍亟待解决。     

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.