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.     

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.     

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.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.