经皮微创锁定加压钢板固定治疗锁骨骨折

目的 探讨经皮微创锁定加压钢板内固定术治疗锁骨骨折的临床应用，以及对其临床疗效的评价。方法 应用间接复位技术，通过建立骨折两端皮下隧道，采用锁定加压钢板内固定治疗锁骨骨折12例。结果 全部病例获随访，时间10～18个月，平均13个月。骨折愈合时间为6～10周（平均8周），无骨折延迟愈合、不愈合、感染及内固定失败等并发症。结论 经皮微创锁定加压钢板内固定治疗锁骨骨折符合生物学固定（BO）原则，锁骨下动脉、静脉、神经硬肺组织的损伤风险较小，有利于锁骨骨折的愈合及骨折端软组织的修复。     

经皮微创锁定加压钢板内固定术的临床应用

目的探讨经皮微创锁定加压钢板内固定术的临床应用及其疗效。方法应用间接复位技术，通过建立骨折两端皮下隧道，采用锁定加压钢板内固定治疗胫腓骨干骨折15例，锁骨骨折12例，肱骨骨折4例。结果所有患随访4～18个月，平均10个月。骨折愈合时间：胫骨10～20周(平均12周)，1例骨折延迟愈合(20周)，无骨不愈合；锁骨6～10周(平均8周)，肱骨8～13周(平均11周)，均无骨折延迟愈合及不愈合。所有病例无感染及内固定失败等并发症。结论经皮微创锁定加压钢板内固定符合生物学固定(BO)原则，有利于骨折的愈合及软组织的修复。     

经皮微创加压螺钉内固定治疗腕舟状骨骨折

目的探讨采用经皮微创加压螺钉内固定治疗腕舟状骨骨折的疗效。方法采用经皮微创加压螺钉内固定治疗腕舟状骨骨折9例。结果本组获随访3~6个月,骨折均获得愈合,骨折平均愈合时间为8周。患者于功能活动时均无腕部疼痛,腕关节活动度均达到对侧的90%以上。结论采用微创方法置入加压螺钉内固定治疗新鲜腕舟状骨骨折,近期疗效满意。     

颈前路单枚中空加压螺钉内固定治疗齿突骨折

目的初步比较经颈前路单枚单头螺纹中空加压螺钉与双头螺纹中空加压螺钉内固定治疗齿突骨折的效果。方法1997年4月～2003年4月,对20例齿突骨折行经颈前路单枚中空加压螺钉内固定术,其中单头螺纹中空加压螺钉12例,双头螺纹中空加压螺钉8例。Anderson分型:Ⅱ型16例,浅Ⅲ型4例。其中3例伴有单侧椎间关节内撕脱性骨折。观察手术时间、术中出血量、术后骨折愈合以及颈部活动情况。结果手术时间110～150min,平均125min。术中出血20～100ml,平均42ml。术中无一例发生副损伤。术后随访2～72个月,平均14.7个月;19例骨折正常愈合,1例延迟愈合;17例骨折愈合后颈椎活动恢复正常,3例伴单侧椎间关节内骨折者颈部旋转功能较正常减少20%。两种螺钉固定的手术时间、术中出血量、骨折愈合时间和颈椎活动功能无明显差别,差异无显著性(P >0.05)。结论单枚单头螺纹中空加压螺钉与单枚双头螺纹中空加压螺钉固定齿突骨折均可获得良好效果。     

经皮穿刺中空加压螺钉固定治疗齿状突骨折

目的讨论经皮穿刺中空加压螺钉固定治疗齿状突骨折的临床效果。方法7例齿状突骨折采用牵引复位后,经皮穿刺单枚中空螺钉加压内固定治疗。结果7例均获随访,时间6～24(13±3.2)个月,骨折均愈合,临床症状消失。结论经皮穿刺单枚中空加压螺钉固定治疗齿状突骨折,临床疗效好;掌握好手术适应证、术前良好的复位是手术成功关键。     

微创空心螺钉髓内固定治疗锁骨骨折

目的 探讨微创空心螺钉髓内固定治疗锁骨骨折的手术方法及临床疗效.方法 回性性分析2009年4月至2010年10月采用微创空心螺钉髓内固定治疗65例获得随访的锁骨骨折患者资料,男41例,女24例;年龄19～67岁,平均(35.8±17.6)岁;根据Craig分型,Ⅰ型29例,Ⅱ-Ⅱ型36例.沿锁骨前缘做横切口,骨折远、近端暴露比例大致为2∶3.髓内向远折端肩峰穿入引导针,骨折复位后将引导针逆行回穿入骨折近端,空心螺钉加压固定.术后采用Neer肩关节活动评分评价患肩功能.选取同组医生以往采用重建钢板固定的65例患者进行对照研究,研究项目包括手术时间、术中出血量、骨折愈合时间、Neer肩关节活动评分及并发症.结果 空心螺钉组切口长度为4～5 cm,重建钢板组为10～11 cm.随访摄X线片证实两组患者骨折均愈合,空心螺钉组骨折愈合时为(13.2±6.9)周,重建钢板组为(16.3±8.7)周;两组患者随访时间均为6～20个月,平均10.6个月.空心螺钉组Neer肩关节活动评分为(96.6±3.4)分,重建钢板组为(94.2±5.8)分.两组均无一例发生感染、局部皮肤坏死、骨折不愈合等并发症.空心螺钉组随访期间出现退钉5例、骨折移位3例,予控制活动后骨折愈合;重建钢板组有4例皮缘愈合略差,经间断拆线换药后切口愈合.骨折愈合后,空心螺钉组在门诊局麻下取出空心螺钉,重建钢板组住院在臂丛麻醉下取出重建钢板.空心螺钉组与对照组骨折愈合时间比较,差异有统计学意义;两组Neer肩关节功能评分比较,差异无统计学意义.结论 微创空心螺钉髓内固定治疗锁骨骨折具有创伤小、骨折愈合快,且节约医疗费用等优势.     

小切口逆行穿针粗空心钉固定治疗锁骨中段骨折

目的介绍大口径中空加压螺钉逆行穿钉治疗锁骨中段骨折的临床方法。方法 2008年12月至2009年8月,手术治疗34例锁骨中段骨折患者,其中32例采用大口径空心螺钉逆行固定,采用Neer肩关节活动评分对患肩进行评价。结果所有病例均获随访,时间4～8个月。骨折均愈合,愈合时间3～5个月。平均3.5个月。无空心螺钉松动、弯曲、断裂及骨折错位等发生。按Neer肩关节活动功能评分标准,本组平均97分。结论大口径中空加压螺钉逆行穿钉治疗锁骨中段骨折是一种简单,快捷,疗效确实的手术方式。     

闭合复位空心加压螺钉治疗股骨颈骨折42例

目的探讨闭合复位中空加压螺钉治疗新鲜股骨颈骨折的方法和疗效。方法自2000年5月至2008年5月,采用闭合复位、2枚或3枚中空加压螺钉内固定治疗新鲜股骨颈骨折42例,强调骨折解剖复位和围手术期的治疗。结果所有病例获得随访,随访时间6个月～3年,平均1年8个月。获得骨性愈合37例,占88．10％;出现股骨头缺血性坏死2例,占4．76％;发生骨折不愈合3例,占7．14％。无螺钉松动、退出、弯曲断裂等并发症。结论闭合复位、中空加压螺钉治疗新鲜股骨颈骨折疗效可靠,有较高的愈合率,是临床治疗的首选方法。影响骨折预后的相关因素有骨折类型、复位质量、内固定质量及患者的全身状况。     

经皮微创空心螺钉内固定治疗骨盆前环损伤

目的 探讨C型臂X线机透视下使用空心螺钉经皮微创内固定治疗骨盆前环损伤的方法及其疗效.方法 采用C型臂X线机透视下使用空心螺钉经皮微创内固定治疗骨盆前环损伤21例.结果 随访3～24个月,平均6个月.术后无感染及螺钉松动.所有患者均骨性愈合,平均愈合时间8周(6～12周).结论 经皮微创空心螺钉内固定术具有创伤小、出血少、并发症少、骨折愈合率高、固定可靠、患者功能恢复满意,是治疗骨盆前环损伤的有效方法.     

手术治疗同侧股骨干合并股骨颈骨折

目的探讨同侧股骨干合并股骨颈骨折的手术方法和疗效。方法15例同侧股骨干合并股骨颈骨折均行内固定,其中采用动力髋螺钉内固定2例,加压钢板加中空加压螺钉1例,股骨重建钉3例,股骨髁上髓内钉加中空加压螺钉8例,带旋髂深血管蒂髂骨瓣股骨颈植骨加中空加压螺钉1例。结果股骨颈骨折漏诊4例(漏诊率26.7%)。股骨颈骨折愈合时间为12～20周,平均16周;股骨干骨折愈合时间为14～24周,平均18周。结论高能量损伤造成股骨干骨折有合并同侧股骨颈骨折的可能,必要的影像检查可避免漏诊。及时采用合理可靠的内固定方法治疗,可获得满意疗效。     

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.