椎板钩加压内固定在寰枢椎融合术中的应用

评价椎板钩加压内固定治疗寰枢椎不稳的临床效果。方法对寰枢椎不稳者行Ｃ１－２后路自体髂骨植骨、椎板钩内固定术。包括齿状突骨折６例,陈旧性齿突骨折伴横韧带断裂１例,齿突骨折骨不连续１例。术后颈椎Ｘ线片检查。结果随访３个月－５年,８例均获得骨性愈合。     

Apofix椎板钩治疗创伤性寰枢椎不稳

目的 评价Ａｐｏｆｉｘ椎板钩治疗创伤怀寰枢椎不稳的效果。方法 对创伤性寰枢椎不稳患者行Ｃ１－２后路融合、Ａｐｏｆｉｘ椎板钩内固定术。包括齿状突骨折５例,其中１例伴横韧带断裂。结果 术后随访３￣１１个月,颈椎侧位Ｘ线片检查,５例获骨性愈合。结论寰枢椎后路融合,Ａｐｏｆｉｘ椎板钩内固定术适于治疗创伤笥寰枢椎不稳;解剖复侠是手术成功的主要。     

寰枢椎后路融合术治疗陈旧性枢椎齿状突骨折12例

目的：报告陈旧性枢椎齿状突骨折引起寰枢椎不稳的治疗。方法：采用寰枢椎后路植骨融合钢丝固定术。结果：经上述方法治疗的12例,随访3－36个月,11例同骨性愈合,1例纤维愈合,计优8例,良2例,进步2例。结论：寰枢椎后路融合钢丝固定术是治疗陈旧性枢椎齿状突骨折简单、有效的方法。     

寰枢椎椎板减压联合寰枢椎椎弓根钉术中复位固定融合术治疗新鲜Ⅱ型齿状突骨折并颈髓损伤

目的总结应用经后路寰枢椎椎板减压联合寰枢椎椎弓根钉内固定,术中提拉复位固定颗粒状植骨融合术治疗新鲜Ⅱ型齿状突骨折并颈髓损伤的临床疗效。方法自2010—11—2013-05对7例新鲜Ⅱ型齿状突骨折合并颈髓损伤应用经后路寰枢椎椎板减压联合寰枢椎椎弓根钉内固定。术中提拉复位固定颗粒状植骨融合术进行治疗,随访观察患者临床症状和神经功能改善情况,影像学检查寰枢椎复位及植骨融合情况。结果患者均顺利完成手术,术中均无血管及脊髓神经的损伤。所有患者脊髓神经功能恢复较理想,随访期间未发现内固定松动、断裂以及骨折不愈合。结论后路寰枢椎椎板减压联合寰枢椎椎弓根钉内固定系统术中提拉复位固定颗粒状植骨融合是治疗新鲜Ⅱ型齿状突骨折并颈髓损伤比较理想的术式选择。     

Magerl联合Brooks融合术治疗严重的寰枢椎不稳

目的介绍后路内固定治疗严重寰、枢椎不稳的手术方式。方法12例寰、枢椎不稳患者中单纯II型陈旧性齿状突骨折6例,寰、枢椎前脱位5例(其中习惯性脱位2例,伴齿状突骨折2例,伴横韧带断裂1例),寰、枢椎旋转脱位伴横韧带断裂1例。采用后路C1,2经关节螺钉联合Brooks融合术治疗。结果12例寰、枢椎不稳患者中11例共放置经关节螺钉22枚,1例陈旧性齿状突骨折患者因C2单侧椎板上缘劈裂仅行Brooks融合术。本组患者术中无椎动脉、硬脊膜破裂和脊髓损伤等并发症,随访3~32个月,植骨全部融合。结论Magerl联合Brooks融合术是治疗严重寰、枢椎不稳的有效方法,可提供有效的固定和提高植骨融合率。     

双侧寰椎椎板钩及枢椎椎弓根内固定在寰枢椎融合术中的初步应用

目的初步评价双侧寰椎椎板钩及枢椎椎弓根内固定技术治疗寰枢椎脱位的临床效果。方法2004年10月~2007年2月,采用自体髂骨植骨、双侧寰椎椎板钩及枢椎椎弓根内固定技术共治疗寰枢椎脱位21例,男14例,女7例。其中,陈旧性齿突骨折11例,齿突游离小骨6例,横韧带断裂4例。术前ASIA(American spinal injury association)脊髓神经功能分级(2000年修订):C级3例;D级12例;E级6例。结果随访3~25个月,平均随访8个月。21例均获得骨性融合。术后ASIA脊髓神经功能分级:D级5例;E级16例。无患者因手术操作致椎动脉和脊髓损伤。结论与传统寰枢椎后路融合术相比,本术式操作简便易行,生物力学稳定性良好,植骨融合率高,且能够在术中对寰枢椎进行加压复位,有利于提高术后临床疗效。该术式在寰枢椎融合术中具有较高的推广应用价值。     

寰枢椎经后路椎弓根钉板/棒系统固定融合治疗上颈椎不稳

目的探讨和评估寰枢椎椎弓根钉板/棒固定融合治疗上颈椎不稳的临床疗效和应用价值。方法对2005年5月-2007年6月收治的16例寰枢椎不稳患者（其中先天性齿突发育不良2例,创伤性陈旧性寰枢关节脱位6例,C2椎管内肿瘤1例,陈旧性齿突骨折7例）施行后路寰枢椎椎弓根钉棒固定术并行自体髂骨植骨融合,其中1例难复性脱位者先行前路松解术。结果全组病例未发生与置钉相关的并发症;所有病例术后随访12-24个月,临床症状得到不同程度的改善,复查X线片、CT未见上颈椎失稳及复位丢失,螺钉位置良好,无松动、断钉,术后随访效果满意。结论寰枢椎椎弓根钉棒固定治疗上颈椎不稳,效果良好,是寰枢椎后路固定较好的手术方式。     

枢椎椎板螺钉治疗上颈椎不稳的临床研究

目的探讨枢椎椎板螺钉技术的临床应用和适应证。方法2004年10月至2008年12月,采用后路枢椎椎板螺钉技术治疗上颈椎不稳35例,男19例,女16例;年龄23～73岁,平均45岁。AndersonⅡ型和Ⅲ型齿突骨折19例,寰椎横韧带断裂1例,先天性游离齿突并寰枢椎不稳2例,寰椎骨折合并寰枢椎不稳7例,不典型Hangman骨折并C2-3不稳1例,C2-3创伤性不稳5例。患者均采用颈椎后路Vertex钉棒系统固定。结果35例患者共置入枢椎椎板螺钉68枚,术中无一例发生脊髓和椎动脉损伤。患者均获得随访,随访时间6个月～4年,平均25.5个月。随访时X线片均未见明显颈椎不稳、内固定失败及螺钉松动退出。11例患者螺钉穿出椎板背侧,但无症状出现。结论枢椎后路经椎板螺钉技术固定牢固,操作简单,相对安全,特别适用于C2椎弓根发育异常或骨折不能采用椎弓跟固定的患者。     

寰椎椎板挂钩及寰枢椎关节间隙螺钉固定术治疗创伤性横韧带断裂

目的探索创伤性横韧带断裂伴寰枢椎不稳的手术治疗方法。方法总结8例创伤性横韧带断裂伴寰枢椎不稳采用一种新的寰枢椎后路内固定术--双侧寰椎椎板挂钩及寰枢椎关节间隙螺钉固定术及自体髂骨植骨融合的临床资料,男7例,女1例,年龄10～62岁,平均30岁。病因有单纯横韧带断裂,寰椎爆裂骨折并横韧带断裂。结果 8例患者经平均6个月,3个月～5年随访,均获得骨性愈合,取得满意疗效。结论寰椎椎板挂钩及寰枢椎关节间隙螺钉固定植骨融合术具有安全,术后即刻稳定,植骨融合率高特点,为创伤性横韧带断裂伴寰枢椎不稳后路理想术式。     

枢椎经椎板螺钉联合寰椎侧块螺钉内固定术的临床应用

目的 探讨后路经枢椎椎板螺钉联合寰椎侧块螺钉固定技术治疗上颈椎不稳的临床疗效和并发症.方法 2003年10月至2006年12月,采用此技术治疗寰枢椎不稳17例,男12例,女5例;年龄34～73岁,平均42.5岁.Anderson Ⅱ型和Ⅲ型齿突骨折14例,寰椎横韧带断裂1例,先天性游离齿突并寰枢椎不稳2例.均有寰枢椎半脱位或不稳,表现为不同程度的颈枕区疼痛,活动受限.枢椎经椎板螺钉固定技术以棘突和椎板的交界处椎板头尾方向的中点为进钉点,为避免钉道的相互干扰,第1枚螺钉的进钉点通常选择枢椎椎板的偏头侧,另1枚螺钉的进钉点偏尾侧,用高速磨钻在进钉点磨去少许皮质骨开窗后,用手钻向枢椎对侧椎板钻孔,螺钉方向在直视下与椎板平面并行,并稍向枢椎椎板背侧倾斜,以确保螺钉不穿破椎板腹侧皮质侵犯椎管,宁可穿破枢椎椎板背侧皮质骨.内固定系统均使用颈椎后路Vertex钉棒系统同定.结果 术中无一例发生脊髓和椎动脉损伤.有2例患者在剥离寰椎后弓下缘时,损伤静脉丛,用明胶海绵压迫止血成功.术后CT示枢椎椎板螺钉位置良好,未见侵犯枢椎椎管和脊髓.随访术后X线片未见明显颈椎不稳、内固定失败及螺钉松动退出.结论 枢椎后路经椎板螺钉技术固定牢固,操作简单,相对安全,值得进一步推广.     

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.     

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.     

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.     

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.