关节镜用于儿童膝关节疾病的诊治

探讨关节镜对儿童膝关节疾病的诊治价值。方法:对51例患儿作了膝关节镜检查和治疗。其中半月板损伤39例,翼状韧带3例,棚架4例,内侧副韧带损伤4例及出血性滑膜炎1例。结果:所有病例都获得明确诊断和针对性治疗,经随访均得到康复。结论:应用关节镜诊治儿童膝关节疾病具有独特的优点:无需切开关节,关节腔内直视下操作,诊断正确率高,损伤小,可避免传统手术所致的不可逆的软骨损害,术后恢复快。     

射频汽化仪在关节镜下治疗膝关节疾病中的应用

目的探讨射频汽化仪在关节镜下治疗膝关节疾病的疗效。方法采用Arthrocare 2000射频汽化仪对126例膝关节疾病进行关节镜手术，其中半月板损伤72例，滑膜炎20例，骨性关节炎15例，髌骨半脱位8例，滑膜皱襞综合征6例，前交叉韧带部分损伤5例。结果126例术后3个月均获随访，无一例切口或关节感染。术后3个月膝关节功能按Neer评分标准：优82例，良35例，可9例，差0例。优良率92．9％。结论使用射频汽化仪在关节镜下治疗膝关节疾病能使手术简便且精确，有效地止血，创伤小，同时能减少对邻近组织的损伤，术后膝关节功能恢复良好。     

误诊为半月板损伤的膝关节紊乱的关节镜诊断和治疗

[目的]探讨临床半月板损伤的鉴别,提高膝关节紊乱的临床诊断水平.[方法]2004年以来对62例经临床检查和MR检查诊断为半月板损伤的患者经关节镜检查确诊为非半月板损伤的膝关节紊乱.男35例,女27例,年龄16～59岁.髌内侧滑膜皱襞综合征15例,Hoff's病8例,滑膜软骨瘤病11例,滑膜瘤6例,髌骨半脱位7例,剥脱性骨软骨炎6例,色素沉着绒毛结节性滑膜炎7例,滑膜血管病2例.全部病例均在关节镜下确诊后,一期行镜下手术治疗.[结果]62例术前诊断为半月板损伤的患者经关节镜检查确诊为非半月板损伤的膝关节紊乱,随诊11～27个月,术后较术前临床症状明显改善.疗效评定:优30例(49%),良23例(37%),可9例(14%).[结论]膝关节内很多疾患尽管病因不同,但在临床症状、体征方面有许多相似之处,只有通过临床仔细的鉴别诊断,才能提高诊断的准确率,不能单纯依据MR进行诊断,关节镜检查是确诊的重要手段.     

膝关节创伤的关节镜手术进展

膝关节损伤指涉及膝关节的骨、软骨和关节内结构(交叉韧带、半月板等)的急性或慢性创伤。膝关节是结构复杂的负重关节,创伤机会多,病废率高。传统的诊断和治疗方法都存在一定的局限性,临床疗效并不满意,常导致关节失稳和创伤性关节病变的发生,影响关节功能。应用关节镜技术是诊断和治疗急性和慢性关节创伤的微创治疗方法。随着关节镜手术理论和技术的普及和提高、关节镜设备、器械和方法的改进,更显示了它是治疗关节创伤的一种重要手术方法〔1〕。1　急性膝关节创伤不同暴力的方向和程度,以及肢体所处的位置和动作,产生的急性膝关节创伤后有…     

膝关节镜下半月板切除术的护理配合体会

<正>膝关节镜手术是微创外科技术在骨科领域中的重大进展,对各关节疾病的诊断与治疗作用越来越受到患者与医生的青睐。可在直视下观察、处理关节内病变,明确诊断,指导手术方法,同时避免了因盲目切开探查造成的损伤,具有切口小、创伤小、疼痛轻、卧床时间短、切口美观、并发症少、临床效果满意度高等优点,大大提高了患者的生活质量。半月板损伤是膝关节常见疾病,半月板损伤的膝关节镜手术包括膝关节镜下半月板部分切除、半月板成形术、半月板修复术。     

射频汽化仪用于膝关节镜手术的临床初探

目的探索冷融化技术在膝关节镜手术中的应用前景和手术技术。方法采用 ArthroCare 2000汽化仪对 20例不同膝关节疾病患者施行关节镜手术。关节镜下诊断疾病分别为：半月板撕裂 6例,股骨髁关节软骨退变 6例,髌骨半脱位 5例,滑膜增生性炎症 2例,前十字韧带部分损伤 1例。通过汽化仪做膝关节镜下半月板部分切除、损伤软骨面及韧带修整、滑膜部分切除以及髌骨外侧支持带松解术等。结果术后膝关节无须加压包扎,分别于术后 24、 48及 72 h对术侧膝关节做浮髌试验检查,均为阴性。术后 24 h行 CPM锻炼,均无明显膝关节疼痛。患者自觉症状良好。镜下观察关节和半月板软骨处理面光整,无出血。结论 ArthroCare 2000汽化仪操作方便,治疗精确,在切除病损组织时最大限度地减少了邻近组织损伤,同时具有止血功能,有利于早期康复。     

误诊为半月板损伤的弹响膝122例分析

目的探讨误诊为半月板损伤患者弹响膝的发生机制、临床表现、诊断和关节镜治疗。方法回顾性分析122例术前误诊为半月板损伤的弹响膝患者资料,所有患者均接受膝关节镜手术。分析不同病因导致膝关节弹响的部位、响度、发生频率、镜下表现,最终评价关节镜手术疗效。结果许多疾病均可出现膝关节弹响,最常见原因为半月板损伤,其次是关节内游离体、软骨病变、滑膜病变、髌股关节紊乱、韧带及肌腱损伤等。其弹响各有特点,关节镜诊治后91．8％弹响症状完全消失,少数患者残余部分症状？结论膝关节弹响来源多样,半月板源性的弹响最为常见。掌握弹响特点有助于术前正确诊断,提高手术疗效,避免过度医疗。关节镜手术是诊治弹响膝的金标准。     

关节内损伤与关节镜技术的进展

关节内损伤指涉及关节结构的骨、软骨和关节内软组织包括韧带、软骨盘、滑膜等的急性或慢性损伤。传统的诊断和治疗方法由于其局限性常导致关节失稳和创伤性关节病变。关节镜作为一种微创技术，自上世纪80年代以来国内开始用于诊治急慢性关节损伤，随着关节镜手术理论和技术的提高和普及，关节镜设备和器械的改进，关节镜更广泛地应用于诊断和治疗急性关节创伤、关节内骨与软骨骨折、关节内韧带损伤、半月板损伤，肩关节损伤等方面。本文对此进行综述。     

膝关节创伤的微创处理

关节镜技术最早应用于膝关节内创伤微创性诊断与治疗．提高了急性膝关节损伤时关节内软骨损伤的诊断率；可以正确评估半月板损伤的部位、类型和范围，合理选择损伤半月板缝合、部分切除等术式，最大限度保留了半月板；可以进行前、后交叉韧带损伤的修复与重建。关节镜技术结合做创内固定技术可以治疗胫骨平台、髌骨、股骨髁骨折，辅助完成逆行交锁钉治疗股骨远端骨折。经皮微创解剖钢板内固定(如LISS)治疗膝关节邻近股、胫骨干骺端骨折，均提供了临床疗效。     

关节镜治疗盘状半月板损伤的临床疗效观察

膝关节盘状半月板损伤为一常见膝关节疾患,大多发生在膝关节外侧,其原因并不十分清楚,但有着很高的发病率.目前,微创关节镜手术已成为治疗关节内骨折、韧带损伤及盘状半月板损伤的主要方法,根据术中镜视所见,决定具体治疗方式.     

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.     

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.     

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.