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1.
四股半腱肌腱重建兔前十字韧带骨道内的末端形成 总被引:3,自引:0,他引:3
目的观察兔四股半腱肌腱移植物重建前十字韧带后骨道内末端形成和转归的情况。方法成年健康新西兰白兔20只,体重2.9~3.5kg,平均3.2kg。行下肢双侧半腱肌腱反折四股重建右膝前十字韧带,按术后3、6、12、26、52周随机分组,按时间段处死实验动物,每组有2只取材成功后,剩余实验动物即进入下一时间段。实验动物处死后,取右膝关节,打开关节腔,取骨道部分标本常规固定、脱水、透明、包蜡、切片、HE染色,组织学观察骨道内移植物及腱骨交界处生长情况。结果3周时腱骨交界处形成一富含血管的纤维结缔组织;骨道内肌腱部分发生坏死,周边细胞已长入。6周时各处连接情况不十分平行,骨道内腱组织亦被替代。12周时界面组织不同部位也出现生长明显不平行情况。26周时界面组织的成熟程度比较平行,可以见到比较典型的直接止点结构。52周时界面组织基本以直接止点连接为主,但在骨道内仍有部分不成熟的腱,仍可见到不同束之间的界限。结论四股半腱肌腱作为前十字韧带的移植物,同样在骨道内通过界面组织的不断成熟,逐渐形成连接,并向直接止点过渡,但因不同股的存在而不平行。由于应力屏蔽的作用,骨道内部的移植物无法完全塑形,仍保留分束的状态。 相似文献
2.
目的 观察兔异体冻干跟腱重建前交叉韧带(ACL)后移植物Ⅰ型及Ⅲ型胶原的表达.方法 应用兔异体冻干跟腱重建ACL,手术后3、12、26、52周取移植物,行组织学观察,并应用免疫荧光共聚焦技术(CLSM)检测移植物Ⅰ型及Ⅲ型胶原表达的平均荧光值.结果 术后52周,异体移植物组织形态与正常ACL基本一致;正常ACL细胞周围主要表达I型胶原(57.10±5.04),几乎不表达Ⅲ型胶原(6.09±1.34);术后3周,移植物Ⅲ型胶原阳性表达开始增加,12~26周达到高峰,移植后52周仍有Ⅲ型胶原阳性表达(13.17±2.26),与ACL比较差异有统计学意义(P<0.05);术后3周,移植物Ⅰ型阳性表达开始减少,12周后逐渐增加,52周Ⅰ型胶原阳性表达(52.69±2.76)仍与正常ACL比较差异有统计学意义(P<0.01).结论 异体跟腱重建ACL后,重建后移植物组织形态与正常ACL基本一致,但移植物胶原基质组成与正常ACL存在明显差异. 相似文献
3.
目的应用动物模型研究四股半腱肌腱重建兔前交叉韧带(ACL)后的生物力学转归以及是否可以通过将四股半腱肌腱编织改善等张性的方法促进束间融合,改善生物力学性能。方法采用成年健康新西兰大白兔32只,分为两组,每组16只,一组行常规自体四股半腱肌腱重建ACL(常规重建组),另一组行编织的四股半腱肌腱重建ACL手术(编织组)。每组于术后26周和52周各处死8只进行ACL观察,并每组取6只行生物力学测试对比研究。结果常规重建组26及52周共16例韧带中,5例融合为一束,11例存在分束。编织组16例标本中,13例合为一束,3例呈不同程度的分束状态。生物力学测试显示:常规重建的韧带26和52周的最大载荷分别达到正常韧带的22.63%和35.87%,编织组26和52周的最大载荷达到正常韧带的33.17%和67.20%;编织组26、52周标本的最大载荷和硬度均显著高于常规重建组。结论四股半腱肌腱作为前交叉韧带的移植物,各束之间可以发生融合、部分融合以及分束的状态,原因可能与它们之间的相对运动有关,通过编织减少这种相对运动,可以促进各束融合,提高生物学及生物力学性能。 相似文献
4.
前交叉韧带重建后Ⅲ型胶原的表达 总被引:7,自引:0,他引:7
目的 本课题着重研究自身髌腱中1/3骨-腱-骨重建前交叉韧带后1年移植物内细胞生物学行为的变化,重点观察重建后1年移植物内细胞Ⅲ型胶原的表达。方法 通过建立狗自身髌腱中1/3骨-腱-骨重建前交叉韧带的动物模型,采用免疫组化和原位杂交方法检测重建后1年Ⅲ型胶原在重建物中的表达。结果 从常规组织学染色看,重建后1年移植物与正常前交叉韧带结构相似;但免疫组化和原位杂交结果显示:正常前交叉韧带内表达Ⅲ型胶 相似文献
5.
《实用骨科杂志》2016,(5)
目的研究应用自体肌腱添加富血小板血浆重建比格犬前交叉韧带的早期组织学转归及生物力学变化。方法选用健康成熟的雄性比格犬36只,随机分为两组(模型组和实验组),将每组比格犬36个膝关节分别取同侧趾长屈肌腱进行单束双股重建,实验组添加自体富血小板血浆。术后第4、8、12周每组随机抽取6只比格犬处死,分别取12个膝关节(包括股骨端与前交叉韧带),每组随机取8个膝关节做生物力学拉脱试验,另4个膝关节标本进行组织学检查,并对实验数据进行统计学分析。结果组织学观察模型组术后4周时,腱骨界面有纤维血管形成,实验组腱骨界面纤维血管更加密集,排列较有序并有少量Ⅱ型胶原纤维。术后8周模型组有肌腱周围的新骨形成,骨隧道壁增厚。但在此期间,胶原纤维机化不充分,腱骨的连续性偶尔可见;实验组胶原纤维生长成熟,可见腱骨的连续性,并在腱骨界面中心出现少量垂直排列的Sharpey样纤维。术后12周模型组可见少量垂直排列的Sharpey样纤维;实验组腱骨界面可见大量的垂直排列的Sharpey样纤维,此时腱骨愈合已逐步趋于稳定。生物力学测试显示术后第4、8周,两组肌腱都能从骨隧道里拉脱出来。在第12周时,模型组仍可以从骨髓道里被拉脱;实验组肌腱均不能从隧道中被拉出,而是在肌腱中间断裂。结论应用自体肌腱可以重建比格犬前交叉韧带并达到腱骨愈合,添加富血小板血浆可以加快腱骨愈合的速度。 相似文献
6.
《中国矫形外科杂志》2015,(24):2283-2288
[目的]观察比较自体、异体及自体一异体混编肌腱重建前交叉韧带移植物腱骨愈合的组织学变化过程。[方法]取45只新西兰兔,随机平均分为自体组、异体组及混编组。切除兔右膝前交叉韧带,取其双侧趾长伸肌腱,两两随机合成双股自体、异体及混编待移植物后重建兔右膝前交叉韧带。采用HE染色、甲苯胺蓝染色,观察重建术后3、8及12周时移植物腱骨愈合的变化情况。[结果]重建术后3周时,各组移植物腱骨界面均表现为明显的组织坏死及炎性细胞浸润;8周时,3组腱骨界面均可见大量新生组织细胞,胶原纤维纵向无序排列:12周时,自体组腱骨界面间的胶原纤维排列较其他2组更有序,止点4层结构也更清晰;术后各期腱骨界面软骨细胞含量,自体组混编组异体组。[结论]前交叉韧带重建术后在相同的时间点,自体移植物腱骨愈合最优,而混编后的移植物介于自体和异体之间。 相似文献
7.
《临床骨科杂志》2017,(6)
目的观察酸性成纤维细胞生长因子(a FGF)复合胶原蛋白对兔前交叉韧带(ACL)重建后腱-骨界面愈合的影响。方法将30只新西兰白兔随机分为实验组与对照组,每组15只,均取趾长伸肌腱作为移植物。实验组将a FGF/胶原蛋白复合物植入到重建的ACL腱-骨界面,对照组单纯行ACL重建。于术后第4、8、12周分别处死动物取材,将股骨与胫骨端分别固定于生物力学试验机上,测试移植肌腱的腱-骨界面抗拉伸强度,取其绝对值作比较;同时,将股骨隧道和胫骨隧道纵向剖开,取下标本组织学观察移植物界面愈合情况。结果术后第4、8、12周抗拉力强度实验组强于对照组,差异有统计学意义(P0.001)。两组动物均在第4周时移植物与骨隧道之间均形成了纤维结缔组织。术后第12周,实验组肌腱移植物在骨隧道内形成了纤维软骨移行带,类似于正常的纤维软骨连接,而对照组则形成了走向与骨隧道轴向垂直的Sharpey样纤维。结论a FGF复合胶原蛋白能促进兔ACL重建腱-骨界面的早期直接愈合。 相似文献
8.
后交叉韧带断裂和重建对兔膝关节软骨退变的影响 总被引:1,自引:0,他引:1
目的 探讨后交叉韧带(PCL)断裂和重建对膝关节软骨退变的影响。方法将33只新西兰大白兔共分3组,实验Ⅰ组:21只兔右膝关节PCL切断,左膝行单纯关节切开术作为对照组;实验Ⅱ组:12只兔右膝关节PCL切断后即刻重建。对照组、实验Ⅰ组术后6、12、26周处死动物,实验组Ⅱ术后12、26周处死动物。通过墨汁染色、HE染色、甲苯胺蓝染色、免疫组化染色(Ⅰ型胶原,Ⅱ型胶原和Ⅲ型胶原单克隆抗体)及扫描电镜方法对各组膝关节软骨退变的情况进行观察分析。结果实验Ⅰ组:PCL切断后26周标本有明显膝关节退行性改变;PCL切断后26周标本关节软骨继发损伤明显重于对照组术后同期标本;内髁软骨可见范围较大的软骨纤维化现象,达深层,细胞数量减少,Mankin评分平均7.7;纤维化的软骨层Ⅰ、Ⅲ型胶原染色阳性,Ⅱ型胶原染色较浅。扫描电镜上股骨内髁各时间段内都可见软骨损伤,而对照组只表现有垄沟样结构的紊乱。实验Ⅱ组:仅部分标本有轻度软骨损伤,术后26周时滑车及内髁处软骨继发损伤较实验Ⅰ组明显减轻。结论PCL断裂可以继发关节软骨的退行性改变,且以内侧间室和髌股关节为主,并随时间的延长逐渐加重。PCL断裂后即刻重建可以有效阻止关节软骨继发损伤的发生。 相似文献
9.
目的探讨骨形态发生蛋白结合型磷酸钙水泥(rhBMP-2-CPC)对自体腘绳肌腱重建前交叉韧带(ACL)后腱-骨愈合的影响。方法取54只成年新西兰大白兔,建立48只双膝关节ACL完全断裂的自身对照模型,24只用rhBMP-2-CPC充填移植腱-骨隧道界面(实验组),24只未用rhBMP-2-CPC(对照组),6只为生物力学试验的正常组。术后第2、4、8和12周取材进行生物力学检测。结果2、4、8和12周实验组肌腱移植物较对照组抗拉伸的最大载荷明显要大,差异有统计学意义(P<0.05)。结论实验组肌腱移植物的生物力学特性优于对照组;BMP-CPC能促进肌腱移植物在骨隧道内的早期腱-骨愈合。 相似文献
10.
[目的]观察保留残迹对前交叉韧带(anterior cruciate ligament,ACL)重建移植物愈合的影响,并探讨其原因.[方法]新西兰兔30只(封闭群,体重2.9~3.5 kg,平均3.2 kg)随机分为3组,每组10只.取其跟腱为移植物,切断双侧前交叉韧带,随机一侧保留ACL残迹,对侧切除残迹,行前交叉韧带重建.分别于术后4、8、12周处死动物,取关节内重建ACL移植物标本10%多聚甲醛固定、10%EDTA脱钙、包埋、切片,HE染色及Masson、PAS特殊组织化学染色,检测成纤维细胞密度及观察组织学形态,数据采用SPSS 12.0软件进行统计分析.[结果]各时间段保留残迹组移植物HE染色组织切片成纤维细胞密度均高于切除残迹组,两组比较有显著统计学差异(P<0.05),两处理组8周时细胞密度高于4、12周,不同时间段比较有统计学差异(P<0.05).各时间段保留残迹组移植物的组织学表现均优于切除残迹组.[结论]保留残迹ACL重建有利于新生细胞长入替代移植物,促进移植物组织结构成熟. 相似文献
11.
Vasopressor hormone response following mesenteric traction during major abdominal surgery 总被引:1,自引:0,他引:1
A. Brinkmann W. Seeling C. F. Wolf E. Kneitinger C. Schonberger N. Vogt K. H. Orend M. Buchler P. Radermacher M. Georgieff 《Acta anaesthesiologica Scandinavica》1998,42(8):948-956
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-PGF1α (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. 相似文献
12.
Don Dame 《Artificial organs》1996,20(5):613-617
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. 相似文献
13.
Kai von Appen Christoph Weber Udo Losert† Heinrich Schima† Hans-Jürgen Gurland Dieter Falkenhagen 《Artificial organs》1996,20(6):420-425
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. 相似文献
14.
T. Tateishi M. Watanabe H. Nakura M. Tanaka T. Kumai T. Aoki S. Kobayashi 《Acta anaesthesiologica Scandinavica》1998,42(9):1028-1032
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. 相似文献
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. 相似文献
15.
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 H2 O 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. 相似文献
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 H
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. 相似文献
16.
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. 相似文献
17.
Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts 总被引:3,自引:0,他引:3
B. Heindl B. F. Becker S. Zahler P. F. Conzen 《Acta anaesthesiologica Scandinavica》1998,42(8):995-1003
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. 相似文献
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. 相似文献
18.
D. Ma S. M. Sapsed-Byrne M. K. Chakrabarti J. G. Whitwam 《Acta anaesthesiologica Scandinavica》1998,42(6):670-677
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. 相似文献
19.
Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery 总被引:1,自引:0,他引:1
J. Boldt M. Papsdorf S. Piper W. Padberg G. Hempelmann 《Acta anaesthesiologica Scandinavica》1998,42(8):941-947
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. 相似文献
20.
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. 相似文献