颅底脑膜瘤的显微外科治疗

目的　用显微外科技术切除颅底脑膜瘤 ,以提高全切率 ,降低死亡率和致残率。　方法　报道 10 3例经显微外科治疗颅底脑膜瘤 ,根据不同部位的肿瘤采用相应的颅底手术入路切除肿瘤 ,并分析手术方法、结果和并发症。　结果　肿瘤Simpson′sⅠ、Ⅱ级全切除 6 3例 ,次全切除 31例 ,大部切除 9例。术后恢复良好 75例 ,遗留颅神经麻痹 2 4例 ,手术死亡 4例。　结论　颅底脑膜瘤采用颅底外科技术 ,明显缩短了肿瘤显露距离 ,最大限度地减少了脑牵拉 ,同时配合显微外科技术 ,可取得良好效果。     

神经导航在颅内肿瘤切除中的应用

目的探讨神经导航在颅内肿瘤切除中的意义. 方法利用MD-2000系列脑立体定向神经导航切除颅内肿瘤28例. 结果转移瘤8例、脑膜瘤10例均全切,胶质瘤全切8例,次全切2例.导航精度(1.5±0.5) mm.手术时间3～4 h.18例随访6个月,7例胶质瘤中3例复发再手术,5例转移瘤出现颅内新病灶,6例脑膜瘤无复发. 结论在神经导航下切除颅内肿瘤,定位准确,提高手术效果.     

小脑幕切迹脑膜瘤的显微外科治疗

目的:通过对2 0例小脑幕切迹脑膜瘤显微外科治疗的分析,探讨小脑幕切迹脑膜瘤的显微手术治疗方法。方法:总结2 0例小脑幕切迹脑膜瘤的临床表现、神经影像学特征及显微手术方法和术后处理,肿瘤的体积从3×3×3cm到5×6×7cm。结果:肿瘤切除程度按Simpson分级:Ⅰ、Ⅱ级(根治性全切除) 13例,Ⅲ级6例,Ⅳ级1例。本组术后无死亡,术后脑积水行V -P分流1例,一过性象限盲1例。随访2～6年,无复发。结论:枕下幕上入路及幕下小脑上入路是小脑幕切迹脑膜瘤最常采用的手术入路,该入路对小脑幕切迹区域暴露充分,距离近,手术并发症少。手术者良好的显微外科技术、经验和对小脑幕切迹区域显微解剖的了解,是成功切除该区域肿瘤的关键。     

神经导航显微手术切除颅内肿瘤

目的探讨应用神经导航辅助显微外科手术切除颅内肿瘤的作用方法采用VectorVision神经导航系统、以显微外科技术切除215例颅内肿瘤,分析导航定位的准确性及与疗效的关系结果215例颅内肿瘤,全切除209例(97.2%)、次全切除6例(2.8%)。出院时患者症状明显改善186例(86.5%)、无明显变化27例(12.6%),死亡2例(0.9%)应用VectorVision的注册准确性为(1.95±0.54)mm,持续准确性为(0.65±0.32)mm。结论使用VectorVision神经导航系统,在术前可制定详细的颅内肿瘤手术计划,术中可辅助显微手术动态地追踪瘤体,手术定位准确、可靠,有利于颅内肿瘤的全切除并降低手术并发症。     

鞍结节脑膜瘤显微外科手术32例临床分析

目的 报道鞍结节脑膜瘤显微外科手术治疗的临床疗效.方法 回顾性分析显微手术治疗鞍结节脑膜瘤32例的临床和随访资料,对鞍结节脑膜瘤的显微外科手术技巧和视神经功能保护方法进行探讨.结果 鞍结节脑膜瘤显微手术32例,肿瘤全切除31例,其中包括Simpson Ⅰ级全切除20例,SimpsonⅡ级全切除11例,肿瘤次全切除1例.手术后视力改善10例,视力无变化15例,视力变差7例.全切除的病例术后随访14～62个月,未见肿瘤复发.结论 应用显微外科手术全切除鞍结节脑膜瘤,保护视神经功能和严密的颅底重建,能够取得较好的临床疗效.     

神经内镜辅助眶上锁孔入路治疗巨大嗅沟脑膜瘤

目的探讨神经内镜辅助眶上锁孔入路治疗巨大嗅沟脑膜瘤的手术效果及手术技巧。方法采用内镜辅助、眶上锁孔入路（显微手术）治疗12例巨大（≥7cm）嗅沟脑膜瘤。结果肿瘤全切除9例（SimpsonⅠ级切除5例，Ⅱ级切除4例），次全切除（SimpsonⅢ级切除）3例。无手术死亡。10例随访3个月～2年，平均14个月。9例恢复正常生活，1例生活能自理。NRI随访9例，肿瘤无复发。结论利用神经内镜辅助及显微外科技术，采用眶上锁孔入路、对肿瘤进行分块切除治疗巨大嗅沟脑膜瘤，手术创伤小，疗效满意。     

颈静脉孔区肿瘤的显微外科治疗

目的探讨颈静脉孔区肿瘤显微手术的临床疗效。方法分析近4年采用显微外科技术治疗颈静脉孔区肿瘤10例的临床资料．主要临床表现为听力下降和后组脑神经损害．术前行头颅核磁共振和颅底薄层CT扫描，8例行数字减影脑血管造影检查。采用显微外科手术切除．其中经颈静脉孔入路6例．远外侧入路2例，枕下乙状窦后入路2例。结果10例术中肿瘤全切除9例，次全切除1例。病理学示神经鞘瘤6例，神经纤维瘤1例，脑膜瘤1例，转移瘤1例，颅咽管瘤1例术后2例完全清醒后未及时行气管切开术而突发喉头水肿窒息死亡。存活8例磁共振复查显示肿瘤全切除7例，次全切除1例。8例术后症状改善3例，症状不变3例，症状加重2例。结论采用显微外科技术选择适当的手术入路可以较好地切除颈静脉孔区的肿瘤，经颈静脉孔入路可能是该区域肿瘤手术治疗的最佳入路。     

颅底内外沟通性脑膜瘤显微外科手术治疗

目的探讨颅底内外沟通性脑膜瘤的显微神经外科术前准备,手术入路与方式。方法对8例颅底内外沟通性脑膜瘤患者的临床资料进行回顾性分析研究。结果8例颅底内外沟通性脑膜瘤包括肿瘤主体位于前颅凹者3例,肿瘤主体位于中颅凹者4例,位于颅后凹者1例。其中6例患者一期肉眼全切除,2例次全切除主要肿瘤,术后有4例患者（2例次全切除者,2例怀疑镜下残留者）给予辅助伽马刀放射治疗,无手术死亡,患者术后症状均有明显改善。结论颅内外沟通性脑膜瘤的手术方式不尽相同,术前肿瘤供血动脉的栓塞,最佳手术入路的选择,多学科的配合协作是保障手术成功的关键。     

嗅沟脑膜瘤的显微外科手术治疗21例临床分析

目的 报道嗅沟脑膜瘤显微外科手术治疗的临床疗效.方法 回顾性分析显微手术治疗嗅沟脑膜瘤21例的临床和随访资料,对嗅沟脑膜瘤的显微手术技巧和颅底重建方法进行探讨. 结果 21例脑膜瘤显微手术,Simpson Ⅰ级全切除19例(90.5%),SimpsonⅡ级全切除2例(9.5%).术前视力变差的15例,术后视力改善14例,术后视力无改善1例:术后无脑脊液漏发生,Simpson Ⅰ级全切除的病例术后平均随访30个月未见肿瘤复发. 结论 应用显微外科手术全切除嗅沟脑膜瘤和严密的颅底重建,能够取得较好的临床疗效.     

岩尖脑膜瘤的显微外科手术

目的探讨岩尖脑膜瘤的分类和显微外科手术治疗效果。方法对24例经显微手术治疗的岩尖脑膜瘤进行回顾性分析，根据术中所见，分为两型：Ⅰ型，肿瘤侵及海绵窦16例；Ⅱ型，肿瘤未侵及海绵窦8例。结果 Ⅰ型肿瘤全切除11例，近全切除5例，其中4例为海绵窦内残留；Ⅱ型全切除5例，近全切除3例。手术全切除率为66．7％。10例（41．7％）患者术后出现新的颅神经功能障碍。结论Ⅰ型岩尖脑膜瘤手术并发症发生率较高。保证重要血管、神经功能完整的基础上尽量全切除肿瘤。残留海绵窦脑膜瘤可行伽玛刀治疗。     

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.     

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.