胸椎椎管内肿瘤的诊断与显微外科治疗体会

目的：探索胸椎椎管内肿瘤的诊断特点,评估显微外科切除疗效。方法：３５例胸椎椎管内肿瘤的临床特点、影像改变、显微外科切除的疗效进行分析。结果：２９例髓外肿瘤中,８９例采用显微外科技术切除,未见任何手术合并症,受压症状解除快,疗效佳,优于普通手术切除的２０例;６例髓内肿瘤中,采用显微外科切除４例,肿瘤切除率约为７０％,普通手术切除率约２５％。结论：依据影像学特点,采用显微外科技术切除,具有解剖结构层次     

胸椎管内肿瘤的诊断与手术治疗

目的：总结胸椎管内肿瘤的临床特点，探讨其早期诊断的方法，评价其手术疗效．方法：对24例胸椎管内肿瘤患者的临床资料进行回顾性分析．结果：胸椎管内肿瘤以髓外硬膜内型多见，肢体麻木、无力及胸腹腰背疼痛为其主要症状，MRI检查能作出精确的定位诊断及辅助定性诊断，经手术彻底切除后恢复良好。结论：MRI是辅助诊断胸椎管内肿瘤的首选检查方法，早期彻底切除肿瘤是提高治愈率的关键。     

颈胸椎管内肿瘤的显微外科治疗

椎管内肿瘤是脊柱外科及神经外科常见病及多发病之一，占神经系统肿瘤的10％～15％。手术切除是治疗的唯一方法。彻底、精确切除肿瘤，不使受压的脊髓、神经根损伤加重，仍为脊柱外科手术追求的目的拉。随着显微外科技术发展，为椎管脊髓内、外肿瘤切除提供有益的手术尝试。本院于2001年3月～2005年10月利用显微外科技术治疗颈胸椎管内肿瘤28例，现将患者的诊治进行分析：     

原发性椎管内肿瘤的诊治分析

目的探讨原发性椎管内肿瘤的临床特点及手术方法。方法回顾性分析最近3年来我科收治的18例椎管内肿瘤的临床特点、诊断要点及手术疗效。结果本组病人均行手术治疗，16例患者肿瘤完整切除，2例大部分切除。术后均经病理证实为良性椎管内肿瘤，其中神经鞘瘤7例，神经纤维瘤6例，脊膜瘤5例。除1例术后出现不全瘫痪外，其余患者临床症状及神经功能均有恢复。结论椎管内肿瘤以良性居多，手术效果佳，MRI检查及显微外科技术的应用是提高治疗效果的关键。     

单侧部分椎板切除入路显微手术治疗椎管内肿瘤

目的 探讨单侧部分椎板切除治疗椎管内肿瘤对脊柱稳定性的影响和适应证的选择。 方法 对2005年10月至2010年12月椎管肿瘤45例患者采用单剥离一侧椎旁肌,单侧部分椎板切除微创入路,应用显微外科技术切除肿瘤,回顾分析临床资料及随访结果。 结果 神经鞘瘤19例、脊膜瘤11例、神经纤维瘤4例、表皮样囊肿3例和畸胎瘤3例均手术全切除,胸椎管内表皮样囊肿l例和脊髓圆锥部畸胎瘤4例残留少许包膜或瘤体。随访3个月～6年,失访4例。术中肿瘤全切除者无肿瘤复发。1例因胸腔积液肺不张致脊柱畸形。其余病例均无因手术而继发畸形。 结论 单侧部分椎板切除入路治疗椎管内肿瘤损伤小,最有利于脊柱稳定性的维持。对于椎管内与脊髓无粘连可分离的肿瘤,选用单侧部分椎板切除入路切除,可获得较好临床效果。     

颈髓肿瘤的诊断及显微外科治疗

目的:探讨颈椎管内肿瘤的早期诊断及显微手术对外科治疗的临床意义。方法:对1985~2001年收治的74例颈椎管内肿瘤患者的诊断及治疗进行回顾性分析。术前均行X线摄片,12例行椎管碘油造影,17例行CT检查,45例行MRI检查。均采用显微外科手术治疗。结果:颈椎管内肿瘤早期采用椎管碘油造影、CT检查均存在不同程度的漏诊或误诊,采用MRI检查者均能确定肿瘤的部位和性质。74例中行肿瘤全切除58例(78.4%),次全切除5例,大部分切除11例。术后神经功能改善61例,病情加重或无改善10例,死亡3例。结论:MRI对颈椎管内肿瘤有较高的定位、定性诊断价值,对制定手术方案也有指导意义。不同部位和病理类型的颈椎管内肿瘤采用显微手术切除应遵循不同的原则和方法,显微手术具有解剖层次分明、肿瘤切除完全、对脊髓干扰小等优点。     

椎管内肿瘤的诊断与手术治疗

目的探讨椎管内肿瘤的诊断与手术治疗方法。方法27例椎管内肿瘤患者根据肿瘤部位及年龄不同,采用不同手术方法。肿瘤全切除23例,次全切除4例,其中显微外科手术8例。结果术后随访6个月～5年,1例术后复发再手术,手术优良率92．6％。结论椎管内肿瘤手术效果好。MRI检查和显微外科技术的应用是提高治疗效果的关键。如果术中破坏了脊柱的稳定性,重建稳定性非常重要。     

椎管肿瘤致截瘫的临床特点与显微外科切除的疗效分析

目的 探索椎管肿瘤采用显微外科技术摘除的疗效。方法 自1990年以来，共有23例椎管肿瘤致程度不同截瘫病例，对其致瘫原因进行分析。同时提出采用显微外科技术切除肿瘤的方法与优、缺点。结果 经术后3-26个月随访，依据美国脊柱损伤学会对Frankel脊髓损伤修订分级标准评定；除2例术后截瘫未完全恢复外，其它21例瘫痪完全恢复。结论 采用显微外科技术切除椎管肿瘤，具有解剖层次分明，组织分辨率高，肿瘤切除完全，残留肿瘤少，对脊髓，神经根干扰降低到最低限度，其手术效果明显优于普通手术切除。     

椎管内神经鞘膜瘤的临床特点及手术治疗

目的：探讨椎管内神经鞘膜瘤的临床特点及手术方法,为早期诊断和提高手术疗效提供保证。方法：５３例椎管内神经鞘膜瘤患者均经手术治疗,颈椎行“单开门术”暴露椎管,胸椎用电磨行全椎板切除,腰椎则行保留棘上韧带,棘间韧带和棘突的次全椎板切除,颈,胸椎管内外哑铃型肿瘤分别采用颈前路和肋骨横突切除入路。结果：随访４５例,平均随访时间３．５年,优良率为８７％。结论：根据肿瘤不同部位采用不同术式,能充分暴露椎管,手     

32例低位椎管内肿瘤的诊治分析

目的 提高椎管内肿瘤诊断的准确率及疗效。方法 对收治的T10椎体节段以下的低位椎管内肿瘤32例患者均予手术切除，全部切除27例，部分切除5例。结果 32例中早期误诊15例。术后随访6个月～3年，29例恢复日常生活与工作，3例下肢肌力及感觉减弱，无一例复发。结论 以临床特征为基础，配合X线片、腰穿脑脊液检查、MRI检查可降低低位椎管内肿瘤的误诊率，原发性椎管内肿瘤一经诊断，应尽早手术。手术切除具有良好疗效。     

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.     

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.