影像导航引导椎体成形术在治疗胸腰段椎体爆裂骨折中的应用

目的 探讨影像导航系统引导椎体成形术辅助短节段椎弓钉内固定在治疗胸腰段椎体爆裂骨折中的有效性和效果.方法 对28例胸腰段椎体爆裂骨折采用导航引导下的短节段椎弓钉固定结合钙磷骨水泥灌注椎体成形术,内植完成后即行X线片正侧位摄片与导航路径进行吻合测量.结果 本组患者术后内植物位置理想,椎弓钉位置评级:理想106枚(94.5%),6枚突破椎弓根外侧皮质(5%),Ⅱ级2枚.术后1周离床负重行走.椎体高度丢失恢复40%,随访12个月后显示椎体高度平均改变0.2%,过伸过屈动力摄片显示固定段无异常活动,未发现有椎弓钉松动、断裂病例.结论 导航引导椎弓钉植入及钙磷骨水泥灌注椎体成形术,只需1次X线片成像就能做出虚拟的手术环境和路径;使内植物精确植入最佳位置,提高了椎弓钉植入及椎体成形手术的安全性,提高手术疗效.     

椎体成形术辅助短节段椎弓钉内固定治疗胸腰段椎体爆裂骨折

目的　探讨预防胸腰段骨折术后出现继发性后凸畸形、避免椎弓钉断裂的手术方式。方法　对 2 0例胸腰段椎体不稳定爆裂骨折采取短节段椎弓钉固定结合钙磷骨水泥灌注椎体成形术。结果　本组术后 1周离床负重行走 ,3个月后腰背疼痛VAS评分平均减少 6分 ,术后X线摄片显示后凸Cobb角平均矫正 14° ,椎体高度丢失恢复 4 0 % ,随访 12个月后显示Cobb角只丢失0 4° ,椎体高度平均改变 0 15 % ,过伸过屈动力摄片显示固定段无异常活动 ,未发现有椎弓钉松动、断裂病例。结论　短节段椎弓钉固定结合钙磷骨水泥灌注椎体成形术可以使胸腰段爆裂骨折的稳定重建 ,提高手术疗效 ,避免术后内固定失败 ,预防继发后凸畸形。     

改良二维X线导航模拟椎体三维影像引导胸腰段椎弓根钉内固定的临床应用

目的探讨改良二维X线导航模拟椎体三维影像的方式在引导胸腰段椎弓根钉内固定的应用效果。方法对66例胸腰段骨折和腰椎疾病患者行后路椎弓根钉固定撑开复位手术,采用改良二维导航的方法获取手术椎节的正侧位及斜位片,虚拟成椎体的正侧位及椎弓根轴位片,引导椎弓根钉植入术。结果术中共植入280枚椎弓根钉,导航虚拟路径与实际椎弓根钉影像之间的平均位置差为1.5mm,角度平均偏差1.0°。术后CT显示,全部椎弓根钉均位于椎弓根内,未出现涉及或突破皮质的现象;椎弓根钉与椎体纵轴角度平均偏差2.0°。结论采用改良二维X线导航模拟椎体三维影像的方法引导胸腰段椎弓根内固定,提高了置钉的准确性和安全性,简便可行,临床效果显著。     

椎体成形术在胸腰段不稳定骨折中的应用

目的探讨碳酸化羟基磷灰石水泥(CHC)作为充填材料在椎体成形术治疗胸腰段不稳定椎体压缩骨折手术中的应用效果。方法22例胸腰段椎体不稳定压缩骨折患者采用椎弓根螺钉系统撑开复位和内固定,通过骨折椎体的椎弓根进行椎体成形术,在椎体内注入CHC增强椎体,观察其治疗效果。结果术后X线片显示,CHC固化后充填在椎体中前柱,与骨界面结合紧密,椎体的高度平均恢复到80%~100%(95%±3·6%)。随访24~36个月,均未出现椎弓根钉棒断裂和弯曲。结论胸腰段椎体不稳定压缩骨折采用椎弓根螺钉内固定同时行椎体成形术,椎体充填CHC可以有效恢复椎体前柱力学强度,降低椎弓根钉棒断裂的风险。     

椎弓根钉固定结合椎体成形术治疗胸腰椎爆裂骨折的现状与展望

胸腰椎爆裂骨折是脊柱外科的常见疾患．占脊柱外伤的10％～20％。短节段椎弓根钉内固定（short-segment pedicle instrumentation，SSPI）是治疗胸腰椎爆裂骨折的主要手术方式之一，但存在较高的内固定失败率。利用SSPI复位固定后实施椎体成形术是近年来治疗胸腰椎爆裂骨折的新进展。一些椎体成形术用于治疗胸腰椎爆裂骨折后显示出良好的近期疗效。现就椎体成形术与SSPI相结合治疗胸腰椎爆裂骨折的理论基础及临床应用作一综述。     

经伤椎置钉辅以经椎弓根椎体内植骨治疗胸腰段椎体爆裂骨折

目的 观察经伤椎置钉辅以经椎弓根椎体内植骨治疗胸腰段椎体爆裂骨折的疗效.方法 采用经伤椎置钉辅以经椎弓根椎体内植骨治疗36例胸腰段椎体爆裂骨折,均为单节段椎体骨折.结果 随访12～18个月,术前Cobb角、伤椎相对高度分别是21.5°、46.5°,术后分别是2.4°、3.4°,术前术后差别有统计学意义.所有骨折复位满意,无其他并发症.结论 经伤椎置钉辅以经椎弓根椎体内植骨治疗胸腰段椎体爆裂骨折不仅骨折复位满意,而且降低了内固定松动和断裂概率,是治疗胸腰椎爆裂骨折的有效方法.     

经一侧伤椎短节段椎弓根固定联合椎体内植骨治疗胸腰段椎体骨折

目的 探讨经一侧伤椎短节段椎弓根固定联合椎体内植骨治疗胸腰段椎体骨折的可行性及疗效.方法 将自2005年1月～2009年5月行短节段椎弓根钉固定联合椎体内植骨治疗的102例胸腰段椎体骨折随机分为两组.A组行后路短节段椎弓根钉固定结合经一侧伤椎椎弓根固定联合椎体内植骨,B组行后路跨伤椎短节段椎弓根钉固定联合椎体内植骨.结果 本组获随访12～24个月.术后1周后凸Cobb角、椎体前缘高度两组间比较,差异无统计学意义(P＞0.05),末次随访时A组矫正角度、椎体前缘高度丢失量明显小于B组,差异有统计学意义(P＜.05).B组末次随访时腰背痛发病率以及内固定失败率明显高于A组,差异有统计学意义(P＜0.05).结论 经一侧伤椎短节段椎弓根固定联合椎体内植骨治疗胸腰段椎体骨折是一种有效的方法.     

后路短节段椎弓根内固定治疗无神经损伤胸腰段爆裂骨折

目的　探讨后路短节段椎弓根内固定、经椎弓根椎体内植骨对无神经损伤胸腰段爆裂骨折的治疗效果。方法　对 2 2例无神经损伤的胸腰段爆裂骨折 ,采用短节段椎弓根内固定器复位固定、经椎弓根椎体内植骨 ,术前、后摄X线片、CT扫描。结果　术后伤椎高度明显恢复 ,后凸显著矫正 (P <0 0 5 ) ;术后 1年 ,后凸矫正度数大量丢失 (P <0 0 5 )。结论　后路短节段椎弓根内固定是治疗无神经损伤胸腰段爆裂骨折的一种理想方法 ,经椎弓根椎体内植骨不能阻止后凸矫正度数的丢失。     

经伤椎置钉辅以椎弓根椎体内植骨治疗老年胸腰段椎体爆裂性骨折

目的 探讨经伤椎椎弓根二侧置钉辅以经二侧椎弓根椎体内同种异体骨颗粒植骨治疗老年胸腰段椎体爆裂性骨折的临床疗效.方法 采用经伤椎椎弓根二侧置钉辅以经二侧椎弓根椎体内同种异体骨颗粒植骨方法 治疗21例老年胸腰段椎体爆裂性骨折,均为单节段椎体骨折.结果 随访12～24个月,平均16个月.术前Cobb角、伤椎前后缘高度比分别是310、38.5%,术后分别是2.50、95%,术前术后差别有统计学意义.术后摄片复查,所有骨折复位及椎体高度恢复满意,术后随访均未见伤椎高度明显丢失和内固定松动、断裂现象发生.结论 经伤椎椎弓根二侧置钉辅以经二侧椎弓根椎体内同种异体骨颗粒植骨治疗老年胸腰段椎体爆裂性骨折,不仅骨折复位及椎体高度恢复满意,而且降低了内固定松动和断裂概率,是治疗老年胸腰段椎体爆裂性骨折的有效方法.     

椎弓根钉内固定联合PVP或PKP治疗骨质疏松性胸腰椎爆裂骨折

目的探讨短节段椎弓根钉内固定联合经皮椎体成形术(PVP)和经皮椎体后凸成形术(PKP)治疗骨质疏松性胸腰椎爆裂骨折的疗效。方法回顾性分析自2013-10—2016-04采用切开复位椎弓根钉内固定联合PVP或PKP治疗的56例老年骨质疏松性胸腰椎爆裂骨折。结果术后X线片显示内固定位置良好,椎体复位满意,椎体内骨水泥弥散良好,无骨水泥椎管内渗漏及肺栓塞发生。56例均获得随访,随访时间平均18(6~24)个月。术后1周疼痛VAS评分、矢状位Cobb角较术前明显改善,差异有统计学意义(P0.05)。5例合并不全瘫患者术后6个月时Frankel分级均达到E级。结论短节段椎弓根钉内固定联合PVP或PKP治疗骨质疏松性胸腰椎爆裂骨折能较好地缓解疼痛、恢复伤椎高度,能避免因骨质疏松导致内固定失效,对严重椎管狭窄或合并神经损伤者可同时行椎管减压。     

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.     

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.     

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.     

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.