使用颗粒状自体松质骨植骨的寰枢椎后路融合术

介绍一种在头环背心保护下用颗粒状自体松质骨植骨的寰枢椎后路融合术。对３４例寰枢椎不稳的病人施行了寰枢椎后路融合术。用头环背心维持寰椎的复位，将颗粒状的自体松质骨植于寰椎后弓和枢椎椎板的背面，不用内固定，直至植骨融合。３１例病人获得了随访，平均随访时间３０个月，其中２９例融合成功，术后头不背心固定时间平均为１３周，有３例出现了寰椎再移位。颗粒状自体松质骨比块状的全层骨更有利于融合。用头环背心的外固定     

手术治疗寰枢椎不稳

目的对寰枢椎不稳的手术治疗进行探讨。方法31例中齿状突骨折15例,寰椎横韧带断裂4例,枢椎原发肿瘤4例,寰椎椎弓陈旧性骨折2例,类风湿性枕颈部发育畸形6例。28例行颈后路手术,包括枕颈融合术14例,寰枢椎融合术13例,肿瘤病灶清除后植骨1例;另3例枢椎经口腔病灶清除加钛网融合器椎间植骨及钛板将环椎前弓与G固定,其中2例分别行前后路手术。结果31例均获随访,时间3个月～10年,平均13．5个月,全部骨性愈合。术前合并神经系统症状26例,术后症状明显改善14例,加重3例。结论对于由寰枢椎骨折脱位、畸形、肿瘤及横韧带断裂等引起的寰枢椎不稳,应早期进行后路前路融合术。充分控制寰枢椎活动,精心准备植骨床是保证手术成功的关键。     

齿突骨折与迟发性寰枢椎脱位

探讨齿突骨折特点与寰枢椎脱位关系及其外科治疗方法的选择。对５６例齿突骨折合并迟发性寰枢椎脱位,全部施行手术治疗。寰枢椎后结构融合术采用改良式Ｇａｌｌｉｅ法１７例和Ｂｒｏｏｋｓ法１４例;寰椎后弓切除及枕颈融合术２５例。随访１１个月至１０年８个月,平均３年６个月。结果显示：２例枕颈植骨不愈合,１例寰枢植骨不愈合;功能评价：优２６例,良１９例,可１７例,无变化４例。认为陈旧性齿突骨折,造成寰枢椎不稳,最     

齿突骨折与迟发性寰枢椎脱位

探讨齿突骨折特点与寰枢椎脱位关系及其外科治疗方法的选择。对56例齿突骨折合并迟发性寰枢椎脱位,全部施行手术治疗。寰枢椎后结构融合术采用改良式Callie法17例和Brooks法14例;寰椎后弓切除及枕颈融合术25例。随访11个月至10年8个月,平均3年6个月。结果显示:2例枕颈植骨不愈合,1例寰枢植骨不愈合;功能评价:优26例,良19例,可17例,无变化4例。认为陈旧性齿突骨折,造成寰枢椎不稳,最终导致寰枢椎脱位及脊髓压迫症,应积极选择外科治疗达到减压和稳定目的。     

枕颈CD内固定在枕颈融合术中的应用

目的：研究枕颈CD内固定在枕颈融合术中的价值和作用。方法：对13例上颈椎不稳患者行枕颈部自体植骨融合枕颈CD内固定术。其中包括寰枢椎肿瘤4例,陈旧性寰枢椎骨折脱位4例,枕寰枢椎复合性畸形4例,陈旧性横韧带断裂伴寰椎前脱位1例。结果：13例患者均获随访5－27个月,平均10个月。所有病例植骨均完全愈合,无一例发生枕颈CD椎板钩及螺钉松动等并发症。结论：枕颈CD可提供有效的节段固定,适用于枕颈不稳的治疗。     

枕颈融合Cervifix内固定术

目的：研究Cetwifix内固定在枕颈融合术中的价值和作用。方法：对47例上颈椎不稳患者行枕颈部自体植骨融合Cervifix内固定术，其中陈旧性寰枢椎骨折脱位14例，枕寰枢椎复合性畸形13例，寰枢椎肿瘤10例(其中原发性寰枢椎肿瘤6例，转移性寰枢椎肿瘤4例)，寰枢椎类风湿性关节炎伴寰椎前脱位8例，寰枢椎结核2例。结果：47例患者均获随访，时问3～38个月，平均9个月。46例植骨愈合，1例植骨块部分吸收骨不连。31例颈髓神经压迫症状均有不同程度的改善。无一例发生Cetwifix内固定螺钉松动等并发症。结论：Cervifix内固定可提供坚强有效的节段性固定，适用于枕颈不稳的治疗。     

后路寰枢椎椎弓根钉内固定及枕颈融合术治疗上颈椎不稳27例临床分析

目的 探讨应用寰枢侧块螺钉与枢椎椎弓根钉内固定及枕颈融合术治疗上颈椎不稳的疗效.方法 对寰枢椎不稳27例患者采用寰椎侧块螺钉结合枢椎椎弓根螺钉及枕颈融合治疗.结果 27例患者均经寰枢椎螺钉或枕颈融合内固定术,其中一例颅底凹陷患者一期行经口齿状突切除术,二期行枕颈融合术,27例患者无一例发生脊髓和椎动脉损伤.所有患者均获得随访,随访3 ～17个月,平均9个月.术后3个月JOA评分13.5 ～16.9分,平均15.2分,改善率为88.4％.植骨块全部融合,无内固定断裂、松动.结论 后路寰椎侧块螺钉结合枢椎椎弓根螺钉固定及枕颈融合术具有稳定的三维固定效果,可用于治疗上颈椎不稳.     

齿状突游离小骨

齿状突游离小骨较少见到，但其可导致寰枢椎不稳与脊髓压迫。为引起临床医生的警惕，作者报告１７例齿状突游离小骨。除３例无症状者未行手术治疗外，１４例存在寰枢椎不稳者均行枕颈融合，术后均获骨性融合。本组病例术后随访２～１６年，临床症状消失或基本消失者９例，明显减轻者５例。３例非手术治疗者无变化。作者认为，对于齿状突游离小骨存在寰枢椎不稳者应行手术治疗     

头环背心在颈椎外科的应用

作者观察了用头环背心治疗多种原因所致颈椎不稳定的应用效果。用头环背心治疗了１０７例颈椎不稳定的病人，病种包括结核、损伤、肿瘤和畸形。病人分为非手术治疗组和融合术组。融合术包括寰枢椎后路融合术、枕颈融合术和下颈椎融合术。各种融合术都在头环背心的固定下施行，不用任何内固定。测量了２３例病人用头环背心固定前后的肺功能。１０７例病人中有８９例获得了随访，平均随访时间２５个月，非手术组的病人在头环背心固定下均恢复了颈椎的稳定性。在３１例行寰枢椎后路融合术的病人中有２９例融合成功（９４％），３６例行枕颈融合术的病人中有３２例达到了骨性愈合（８９％）。用头环背心固定的平均时间是１３３天，最长的４５０天。统计学结果显示：用头环背心固定后病人肺活量的均数与固定前相比差异有非常显著性（Ｐ＜０．０１），固定后肺活量减少约１３％。并发症包括颅钉松动（２４例）、钉孔感染（４例）、复位丢失（４例）、颅钉穿透颅骨内板（３例）、背心下皮肤压疮（１例）。作者认为头环背心对颈椎失稳的病人是一种安全、有效的外固定器材。借助这种装置，部分需行颈椎融合术的病人可以免去内固定，使手术更安全、简便。头环背心可使病人的肺活量减少。     

寰枢椎不稳及脱位的外科治疗

目的总结和分析寰枢椎不稳及脱位的外科治疗结果，并对其手术方法的选择进行探讨。方法自1998年1月至2004年5月对15例寰枢椎不稳及13例寰枢椎脱位患进行手术治疗，15例寰枢椎不稳均行后路寰枢椎植骨融合内固定术；13例寰枢椎脱位病例中，8例经颅骨牵引寰椎完全或大部分复位，系采用后路寰枢椎植骨融合内固定术，5例牵引后不能复位，行寰椎后弓切除减压枕颈融合术。结果1例寰枢椎脱位病例术后1周死亡，1例寰枢椎脱位病例术后复发，给予颅骨牵引复位后头颈胸石膏外固定3个月，其余病例随访3～24个月，所有病例枕颈部疼痛症状减轻或消失，四肢及躯体感觉恢复接近正常，肌力及肌张力明显改善，寰枢椎及枕颈部植骨在半年左右均达骨性融合，未出现内固定物断裂、脱落。结论术前应熟悉寰枢椎不稳及脱位的各自影像特点，并对其解剖特点、发生机制及其临床特点认识清楚，正确地选择手术方法，术中仔细操作，便能达到满意的治疗效果。     

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.     

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.     

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.     

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.     

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.     

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.