过度扩张对轴型皮瓣血运影响的实验研究

目的：探讨过度扩张对轴型皮瓣血运的影响。方法：以猪臀部双侧以旋髂深血管为蒂的岛状皮瓣分别作为实验组和自身对照组，观察过度扩张后岛状皮瓣成活、激光多普勒微区血流、荧光染色、组织丙二醛含量的变化，并用组织学检查和血管灌注透明标本显示其血管结构及构筑的变化。结果：过度扩张后岛状皮瓣远段的血运显著降低，轴型血管血管网有损伤表现、分而模式改革和长宽比例缩小。结论：过度扩张可影响轴型皮瓣的血运。     

肠血管畸形引起肠道出血的定位诊断

镇江市第一人民医院普外科步雪峰肠血管畸形为粘膜下的微小病变，肉眼难以分辨。根据临床表现、病理改变和病变部位可分成三型：I型为血管扩张型，病变多见于百肠及升结肠．老年人多见；D型为动静脉畸形，多发于小肠．以年轻人为多见；D型为毛细血管扩张型。肠血管畸形是隐匿性消化道出血的重要原因之一，据文献报道该病术后再出血率高达90％左右，术前如何提供可靠诊断依据，准确定位，减少手术盲目性，防止遗漏，是减少术后再发的关键。一、传统的诊断方法。1．气钡双重造影：由于肠血管畸形病变位于粘膜下，该检查对血管异常显示很不可…     

组织扩张对预构轴型皮瓣血供影响的实验研究

目的　研究组织扩张对预构轴型皮瓣血供范围的影响 ,为临床上获取更大面积的预构轴型皮瓣提供理论指导。方法　在同一只兔子腹部的左右侧分别设计、完成以股动、静脉为轴型血管的预构皮瓣 ,右侧腹部仅预构皮瓣未埋置扩张器 (未扩张组 ) ,左侧预构皮瓣下埋置扩张器进行扩张 (扩张组 ) ,分别于预构术后 1、3、5、7、10、14、2 1、2 8、5 6天对扩张组与未扩张组预构皮瓣血供范围进行相关检测。结果　预构皮瓣经扩张后其轴型血管供血范围明显大于未经扩张的预构皮瓣 (P <0 .0 5 )。结论　扩张术可加速皮瓣预构进程 ,增加预构轴型皮瓣的存活面积     

兔股动脉和静脉预构轴型扩张皮瓣的实验观察

目的 通过兔股动脉、静脉预构轴型扩张皮瓣的微循环血流晕动态变化、光镜下结构的改变及其成活面积,为预构轴型扩张皮瓣的临床应用提供依据.方法 选择新西兰白兔40只,随机分为4组:预构轴型扩张皮瓣组、预构轴型不扩张皮瓣组、单纯预构轴型皮瓣组及无蒂游离皮瓣组,每组4只,前2组股动脉、静脉移位后,预构轴型扩张皮瓣组、预构轴型不扩张皮瓣组分别在肉膜深面置入容量为50 ml长方形皮肤软组织扩张器,预构轴型扩张皮瓣组7 d后开始注水;无蒂游离皮瓣组为对照组,未采取预构及扩张处理.定期对4组皮肤进行微循环血流量检测,并取样进行光镜观察.预构术后52 d,前3组形成以预构股动静脉血管束为蒂的岛状皮瓣,游离皮瓣组则形成无蒂游离皮瓣后均原位缝合,观察其成活面积.结果 预构轴型扩张皮瓣组较其他组微循环血流量增加,成活面积大[(97.54±2.73)%],光镜下改变显著(P<0.05).结论 扩张术能促进预构轴型皮瓣的血管化进程,明显增大预构轴型皮瓣成活面积,增加其移植的安全性.     

组织扩张对预构轴型皮瓣血供影响的实验研究

目的研究组织扩张对预构轴型皮瓣血供范围的影响,为临床上获取更大面积的预构轴型皮瓣提供理论指导.方法在同一只兔子腹部的左右侧分别设计、完成以股动、静脉为轴型血管的预构皮瓣,右侧腹部仅预构皮瓣未埋置扩张器(未扩张组),左侧预构皮瓣下埋置扩张器进行扩张(扩张组),分别于预构术后1、3、5、7、10、14、21、28、56天对扩张组与未扩张组预构皮瓣血供范围进行相关检测.结果预构皮瓣经扩张后其轴型血管供血范围明显大于未经扩张的预构皮瓣(P＜0.05).结论扩张术可加速皮瓣预构进程,增加预构轴型皮瓣的存活面积.     

组织瓣移植修复创面与瘢痕畸形

报道利用多种组织瓣移植修复严重深度创面与瘢痕畸形２５５例。利用肌皮瓣６种修复５４例，轴型皮瓣１０种修复５０例，筋膜皮瓣７种修复４４例，皮下组织蒂皮瓣１２例，带蒂薄皮瓣修复５４例，带真皮下血管网整张皮片修复３８例，静脉干动脉化游离皮瓣、大隐静脉逆行岛状皮瓣及小隐静脉逆行岛状皮瓣修复各１例。移植组织的成活率为９９．２％，Ｉ期愈合率为９４．５％。根据手术距伤后时间与创面情况分为急诊期、感染期、择期手术，     

症状性大脑中动脉狭窄的介入治疗

目的评价血管内支架植人术和球囊扩张术对症状性大脑中动脉狭窄的疗效。方法对37例反复发生短暂性脑缺血（TIA）的大脑中动脉狭窄患者,根据Mori和治疗路径分型选择手术方式：路径I、Ⅱ型且MoriA型行支架植入术;路径III型或MoriB、C型采用球囊扩张术。结果21例行支架植入术,16例行球囊扩张术。支架植入术组成功扩张20例,狭窄率由76％降至12％;1例术后因血管破裂而死亡。球囊扩张术组成功扩张14例,狭窄率由69％降至15％,1例由于路径过度纡曲失败。术后随访,支架植入组17例TIA症状消失,2例症状有明显改善,2例TIA复发;球囊扩张术组12例TIA消失,4例TIA复发。结论两种方法治疗MCA狭窄均有效,根据Mori及手术入路分型合理选择介入手术方式可能是提高手术成功率的较好策略。     

皮瓣扩张术

将医用硅胶扩张囊埋入患者供区皮下间隙,筋膜下间隙或肌层下间隙,术后注水扩张致扩张囊完全膨胀。然后,根据需要在该区或其邻近部位制作皮瓣用于修复和重建缺损的组织。这种皮瓣叫做扩张后皮瓣,用扩张器制作皮瓣的方法叫皮瓣扩张术。广义上讲,扩张后皮瓣包括任意型皮瓣和轴型皮瓣;狭义的看,扩张后皮瓣单指经扩张预制后的轴型皮瓣。临床应用时可分为带蒂轴型扩张皮瓣和游离轴型扩张皮瓣两种。下面就轴型皮瓣扩张预制(构)的基础理论及临床应用的有关问题介绍如下:一、轴型皮瓣扩张后的组织学改变皮瓣扩张后会发生一系列的组织学改变。由于扩张…     

原位大隐静脉腘静脉转流术治疗股静脉栓塞

我院1994.1～1999.6对12例股静脉栓塞行原位大隐静脉股腘静脉转流术。术前行下肢深静脉造影及大隐静脉造影,以确诊股静脉血栓形成为完全阻塞或部分再通以阻塞为主者,并显示大隐静脉通畅。手术要点在于精确细仔的血管吻合,大隐静脉游离不宜过长,以避免游离过程中损伤大隐静脉,而降低手术通畅率。另外术后应用抗凝治疗,早期活动。本组病人治愈率83.3％,有效率16.7％。     

扩张后隐神经营养血管皮瓣修复足踝部软组织缺损

目的　应用扩张后隐神经营养血管逆行岛状皮瓣修复足踝部软组织缺损。方法　解剖学研究证实与大隐静脉伴行的隐神经的营养血管呈丛状分布 ,与深浅筋膜内的血管网广泛交通 ,在此基础上以大隐静脉为轴线 ,设计逆行岛状皮瓣 ,扩张后转移至受区。结果　 1999年 6月以来临床应用 6例 ,皮瓣面积最大为 12cm× 10cm ,皮瓣完全成活。结论　扩张后隐神经营养血管逆行岛状皮瓣安全可靠 ,操作简单 ,为足踝部创面修复提供了一种可靠的方法。     

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.     

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.     

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.     

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.     

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.