胸腰椎爆裂型骨折的外科治疗

目的探讨胸、腰椎爆裂型骨折手术治疗方法的选择。方法采用腰椎后路短节段椎弓根螺钉内固定术治疗胸、腰椎爆裂型骨折69例,对比患者手术前后神经功能评价、影像学指标及自我满意率。结果平均随访32个月,Frankel评分平均提高1.2级;Cobb角由术前平均35°恢复至6°;椎体塌陷由术前的62%恢复至13%;19例术后CT扫描平均椎管内占位由61%恢复至32%;术后优良率(自我满意率)为72%。结论手术治疗可使患者尽早恢复日常生活,有效恢复脊柱序列及椎管容积、矫正后凸畸形,有利于胸、腰椎功能恢复。     

应用DRFS骨折椎内固定、小关节融合治疗胸腰椎爆裂骨折

目的　探讨胸腰椎爆裂骨折内固定新方法。方法　对 2 8例胸腰椎爆裂骨折应用DRFS行骨折椎及邻椎内固定 ,小关节融合术治疗。对手术方法 ,疗效进行总结和随访。结果　平均随访 18个月。后凸成角术前平均 2 5° ,术后 5°;椎体前高术前平均 32 % ,术后恢复到 95 % ;骨折椎体后上角突入椎管术前平均 2 8% ,术后完全复位。随访无椎体前高及脊柱后突矫正角度丢失。 2 5例神经功能获得Frankel1～ 3级改善。结论　骨折椎内固定明显提高复位与固定效果。该术式简单、安全、复位完美、固定牢靠、疗效优良     

改良后入路环椎管减压治疗胸腰椎爆裂骨折

目的探讨胸腰椎爆裂骨折的治疗方式.方法根据骨折类型不同,采用后入路不同方式的环椎管减压内固定术治疗胸腰椎爆裂骨折36例.结果36例平均随访26个月,术前后凸成角平均24°,术后平均10°;术前椎管狭窄率平均55%,术后平均10%.33例获得Frankel分级1～3级以上的改善.结论改良后入路环椎管减压内固定治疗胸腰椎爆裂骨折具有诸多优点,可做为治疗新鲜爆裂骨折的首选术式.     

后外侧减压AF固定治疗胸腰椎爆裂骨折并截瘫

目的:探讨后外侧减压椎间植骨AF固定治疗胸腰椎爆裂骨折并截瘫患者神经功能恢复的作用。方法:后外侧减压AF固定治疗胸椎爆裂骨折并截瘫的57例患者进行治疗,术前术后均对患者的神经功能进行了Frankel分级评估。结果:术后随访10月~2年(平均13月),所有病例植骨融合,术后后凸的Cobb角由术前平均25°恢复到5°,内固定变形2例,断裂1例Frankel分别除4例无变化,其余53例均有1~2级恢复。结论:后外侧减压,可完全去除后突骨块(5周内),椎间植骨融合AF固定可促进胸腰椎爆裂骨折并截瘫的神经功能的恢复,系统的康复锻炼可减少截瘫的并发症。     

伸展体位与短节段椎弓根螺钉治疗胸腰椎爆裂性骨折

目的　探讨应用伸展体位加短节段椎弓根螺钉系统治疗胸腰椎爆裂性骨折的效果。方法　采取肢体伸展体位使伤椎间接复位、椎弓根螺钉系统固定治疗胸腰椎爆裂性骨折 2 7例。结果　随访 3～ 2 3个月 ,伤椎前、后高度由术前的平均 4 7 3%、6 3 5 %恢复到术后正常高度的 90 2 %、94 5 % ;后凸Cobb角由术前平均2 1 6°恢复到术后平均 2 8°。结论　伸展体位加短节段椎弓根螺钉系统对胸腰椎爆裂性骨折的治疗复位确切、固定可靠、疗效良好。     

AF内固定加椎板关闭术治疗胸腰椎爆裂骨折

目的 比较和评价后路椎板切开骨折复位椎板关闭术和结合AF系统两种不同手术方法在治疗胸腰椎爆裂骨折中的疗效。方法 回顾性分析29例胸腰椎爆裂骨折患者,其中早期8例单纯采用后路椎板切开、骨折复位、关闭椎板的手术;后期用此法并结合AF系统治疗21例。比较术后症状的改善和X线变化。结果 全部病例获得3个月～6年随访,脊髓神经功能及椎体高度均有不同程度恢复。AF内固定组无局部症状,后凸畸形角由术前平均28.4°减少到术后3.1°;单纯组存在腰部症状,后凸畸形角由术前平均26.2°减少到6.9°。结论 AF内固定结合骨折复位椎板关闭术,骨折复位及减压彻底,脊柱稳定性好,术后硬膜外瘢痕粘连少,是治疗胸腰椎爆裂骨折的一种理想方法。     

S-F内固定器治疗胸腰椎爆裂型骨折

目的　探讨使用S -F脊柱内固定器治疗胸腰椎爆裂型骨折的效果。方法　回顾分析从 2 0 0 0年 1月～ 2 0 0 2年 4月使用S-F脊柱内固定器治疗的胸腰椎爆裂型骨折 4 4例 ,比较手术前后的椎体前后缘高度 ,椎管狭窄程度 ,Cobb角及症状恢复情况。结果　经平均 2年左右的随访 ,术后椎体前缘平均高度达正常的 93 8%± 6 2 7% ,较术前增加了 4 2 5 3%。椎体后缘平均高度达到正常的 97 5 9%± 0 0 3% ,较术前增加了 1 6 5 2 %。脊柱后凸Cobb为 4 98°± 3 32°。较术前矫正了 1 4 6 8°。CT片显示椎体后突骨块占椎管前后径的比例为 9 5 9%± 7 2 1 % ,较术前减少 2 7 71 %。统计学分析差异有显著性 (P <0 0 5 )。有神经功能损伤者 ,术后平均改进一级以上。在术后二周与术后一年以上的X线片相比较其椎体前缘的高度平均仅丢失 1 0 % ,椎体后缘的高度平均丢失 0 8% ,Cobb角平均丢失 0 1°。结论　使用S -F脊柱内固定器治疗胸腰椎爆裂型骨折具有操作简单、复位完美、固定牢靠、疗效优良的优点。术中注意不宜过度撑开及双侧不对称 ,对椎板减压者宜作“H”型椎板后路植骨 ,横突间、关节突间植骨融合将提高疗效、减少并发症     

AF内固定治疗胸腰椎爆裂骨折

目的　探讨 AF内固定系统在治疗胸腰椎爆裂骨折中的疗效。方法　回顾性分析了 6 2例胸腰椎爆裂骨折患者在 AF内固定治疗术前、术中及术后情况。结果　全部病例获得了 3个月～ 3年的随访 ,脊柱后凸角由原来的平均 2 8.7°,变为 3.5°,4例患者出现内固定断裂 ,脊髓神经功能及椎体高度恢复。结论　 AF内固定治疗胸腰椎爆裂骨折具有复位确切 ,固定可靠等优点 ,是一种理想的治疗胸腰椎爆裂骨折的方法。     

Steffee钢板内固定治疗胸腰椎骨折

本文报告采用Steffee钢板内固定手术治疗胸腰椎骨折108例。术前平均椎体前、后高度分别是48.3%和75.6%,术后平均椎体前、后高度分别是86.8%和88.1%。术前Cobb’s角平均20.6°,术后平均6°。作者认为Steffee钢板系统结构简单,操作方便,固定坚固,但对有骨折块突人椎管内的爆裂型骨折,骨折块不能复位,椎体后高度恢复较差,建议对此类患者使用RF系统固定。     

保留后韧带结构的AF系统治疗胸腰段爆裂骨折

目的　探讨一种治疗胸腰段爆裂骨折伴截瘫的方法 ,使术后脊柱稳定性较好。方法　用AF系统治疗胸腰段爆裂骨折 5 4例 ,手术时保留脊柱后韧带结构。统计术前术后伤椎前后缘高度、Cobb角资料。结果　术后伤椎前缘高度恢复至 ( 95 1± 8 5 ) % ,后缘高度恢复至 ( 98 5± 7 2 ) % ,Cobb角恢复至 ( 4 8± 2 5 )°。各项指标与术前比较差异有显著性 (P <0 0 1)。术后随访 0 5～ 3 5年 ,神经功能按Frankel评定 :46例提高 1～ 3级。结论　后韧带结构为坚韧有弹性的骨 -韧带条 ,在维护脊柱稳定的过程中 ,有着无法替代的价值。行椎管减压术应保留后韧带结构 ,术后脊柱稳定性较好 ,拆除内固定后脊柱不易滑移后凸 ,疗效优于单纯AF系统内固定手术     

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.     

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.     

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.     

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.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

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.