自体小静脉移植管壁结构组织学变化的实验研究

目的建立大鼠自体小静脉移植的动物模型，观察自体小静脉移植修复小动脉缺损后的血管通畅情况及小静脉移植后管壁结构的组织学变化特点，为临床应用提供资料。方法选用成年雄性Wistar大鼠56只，随机分为两组，每组28只，试验组采用外径0．7～0．9mm的自体小静脉移植，修复其相近外径股动脉的缺损；对照组行小动脉直接吻合术。术后不同时间段行血管取材，光、电镜观察。结果两组大鼠术后血管具有相近的近期及远期通畅率（P〈0．01）。小静脉移植术后24h出现内皮细胞的脱落、坏死，部分平滑肌细胞坏死；术后l周，移植静脉可见新内膜，较正常静脉内膜厚，血管平滑肌层增厚；术后2周，移植静脉新内膜进一步增厚，其中的平滑肌细胞核也明显增多；2～4周，新内膜持续增厚，平滑肌细胞核数开始减少。术后6～8周，新内膜不再继续增厚。移植静脉管壁增厚至一定程度后保持稳定，具有类似动脉的结构特征。结论用外径0．7～0．9mm的小静脉移植修复外径与其相近的小动脉缺损，其结果与同样外径的小动脉在无张力下直接吻合后的即刻通畅率及远期通畅率相近。     

静脉移植在断指（肢）及血管损伤中的应用

1985年以来,我科共做断指(肢)再植45例58个断指(肢),修复四肢血管损伤12例,对其中20例因动脉缺损不能直接吻合者应用自体浅静脉移植修复,重建动脉血运,取得较好效果,报道如下。     

小血管移植在断指再植中的应用

目的 探讨小血管移植在断指再植中的应用。方法 再植47例52指，移植修复动脉52条、静脉11条，其中包括静脉皮瓣修复静脉及皮肤缺损2块，静脉皮瓣修复动脉及皮肤缺损1块。结果 52指再植成活38指。1例2指再植失败，l例3指中1指再植失败，成活率73．1％。结论 小血管移植对于血管缺损状态下的断指再植系唯一选择。     

652指断指再植的临床体会

目的再植指成活是断指再植早期目的,再植指功能恢复是断指再植最终目的。方法末节甲根部以远指体离断采用：（1）吻合一条动脉,一条静脉或两条静脉;（2）吻合一条动脉,另一条动脉作动静脉转流（即远端动脉与近端静脉吻合）;（3）吻合一条或两条动脉,附加拔除甲板或离断指体侧缘小切口放血治疗。单纯血管缺损或伴有血管、皮肤软组织缺损离断指采用移植血管、微型游离皮瓣治疗。结果本组应用显微外科技术再植652指,成活628指,成活率96．3％。术后随诊1-3年,根据断指再植功能评定标准总优良率75．3％。其中离断指伴有血管缺损或皮肤软组织缺损35指,成活35指,成活率100％;甲根部以远指体离断107例。97例成活,成活率90．7％。结论随着显微外科的发展,显微外科技术不断进步．人们生活水平不断提高,对再植指的要求也越来越高,因此对再植手指的适应证应加以放宽。     

多指离断再植的探讨

目的 探讨多指离断再植手术中各阶段处理方法，提高各种断指再植的成功率。方法 手指末节、指尖部的断指再植，吻合1条动脉及静脉或者吻合1条动态加拔指甲、小切口放血处理，手指中节断指再植吻合动，静脉比例为1：1，手指近节的距离断再植吻合动、静脉比列1：2或者2：2。如有血管缺损，行浅静脉移植桥接或者邻指动脉移植修复。临床再植58例，142指。结果 再植58例142指中成活129指，成活率90.8%。术后经3个月-3年随访到46例113指。按断指再植评定标准评定，其中优53指，良44指，可14指，差7指，总优良率85.8%.结论 多指离断再植手术时间长,技术要求高。术中高质量的血管吻合及对血管缺损的正确处理，术后血管危象的防治是提高多手指离断再植成功的关键。加强功能锻炼是再植手指功能恢复的重要环节。     

复杂伤断指再植的临床体会

目的 探讨复杂伤断批的显微外科手再植术式和治疗。方法 对11例22个复杂伤断指进行细致而彻底的清创。指骨缺损长度大于10mm行节段植骨。采用两定点方法吻合血管。对单纯血管缺损长度大于5mm,切取前臂远端掌侧皮下小静脉移植再植;对指血管－神经－皮肤复合缺损,采用邻指含指固有动脉及半行静脉、指固有神经主干皮瓣转位再植,或切取Mu趾腓侧含趾背静脉、趾底动脉神经的半月形皮瓣桥接再植。结果 术后完全成活19个手指。随访4－31个月,断指再植功能评定：优3指,良12指,差4指,优良率78.9％。结论 各种克服组织缺损的断指再植,获得了较满意的再植后手指长度、外形与功能。     

特殊类型断指再植血管损伤治疗的体会

目的 报道伴有血管损伤的特殊类型断指治疗的临床疗效。方法 采用静脉移植桥接、动静脉转流、近端面单侧指动脉结扎、扩大近端骨髓腔的经骨髓腔静脉回流、邻指动脉转位、掌部动脉弓转位以及指背静脉转位吻合等再植方法治疗特殊类型断指。结果 临床再植956例，其中成活911例，成活率95．3％，根据断指再植评定标准进行评定，术后功能优良率90％。结论 采用动静脉转流、近端面单侧指动脉结扎、扩大近端骨髓腔等再植方法可以扩大断指再植适应证，提高断指再植成活率。     

断指再植术中动脉缺损的修复

目的 探讨断指再植术中动脉缺损的修复方法。方法 对137个断指分别采用短缩指骨、静脉移植或动脉移植和邻指动脉转位方法修复。结果 本组成活134指，坏死3指。结论 在断指再植术中，针对动脉缺损的不同类型分别选择有效的修复方法，可提高断指再植的成活率。     

腕掌侧静脉移植在断指再植中的应用

断指再植中,血管必须在无张力下进行吻合,才能保证再植手术的成功。我院自2001年6月至2006年4月,采用患肢腕掌侧静脉移植修复断指再植中指动静脉缺损83例97指,取得满意效果。现报告如下。     

绞窄伤断指动脉缺损再植的探讨

目的 探讨动脉缺损断指再植的手术效果。方法 断指近端动脉缺损施行静脉移植或邻指动脉移植，断指远端动脉缺损施行静脉动脉化。结果 15指动脉缺损断指再植，术后13指成活。结论 动脉缺损的断指再植，术中需行血管移植或静脉动脉化，成活的关键是掌握再植指征、显微操作技术和术后血管危象处理。     

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.     

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.