硬膜外导管在大鼠肾移植血管吻合中的应用

目的建立一种手术难度低,成功率高的大鼠肾移植模型。方法 Wistar大鼠作供体,SD大鼠作受体,将供体腔静脉与受体肾静脉端端吻合,供体腹主动脉与受体腹主动脉端侧吻合,供体膀胱瓣与受体膀胱吻合。根据血管吻合时应用硬膜外导管与否,将受体分为有支架组和无支架组两组。结果有支架组共进行肾移植30次,成活26只;无支架组共进行肾移植20次,成活10只。有支架组的成活率86.7%（26/30）较无支架组50.0%（10/20）明显提高（P〈0.05）,血管吻合总时间（22±2）min较无支架组（32±2）min明显缩短（P〈0.05）。结论硬膜外导管应用于大鼠肾移植血管吻合,降低了手术难度,减少了吻合口出血,提高了手术成功率。     

食蟹猴肾移植模型的建立

目的建立食蟹猴的肾移植模型。方法通过显微外科手术对食蟹猴进行同种异体移植,将供体肾动脉、肾静脉分别端侧吻合到受体腹主动脉、下腔静脉,供体输尿管端端吻合到受体输尿管。结果154例肾移植食蟹猴无一只在手术过程中因意外死亡;无一只因手术感染死亡;无一只因手术并发症死亡;肾热缺血时间（30±4.5）min。结论应用食蟹猴建立肾移植模型,技术成熟,方法可靠。应用此模型评价新型免疫抑制药物,进行免疫耐受、异种移植研究可为临床试验提供更为准确可靠的依据。     

带血管髂骨移植动物模型的建立与评估

目的:探索一种相对简单稳定的大鼠髂骨皮瓣移植手术方式,为髂骨移植诱导免疫嵌合状态的研究建立可靠的动物模型。方法:实验分为3组:空白对照组,不做任何处理;旧术式组,将供者髂骨肌皮瓣移植入受者腹股沟区,吻合供者髂腰动静脉和受者股动静脉;实验组,剥离供者髂骨臀大肌,取供者的髂骨连带肌肉及皮瓣移植于受者的腹股沟区域,将供者的髂总动脉和髂腰静脉分别与受者的股动静脉吻合,随后缝合皮肤。术后所有大鼠给予环孢素A 28天,始剂量16 mg/kg/d,第三周始每周剂量减半,第28天处死大鼠并选取髂骨做病理学检测,观测骨髓细胞量,骨陷窝是否有骨细胞等,以此判断髂骨是否成活。结果:实验组共进行手术15例,皮瓣成活11例,成功率73%;病理检测皮下髂骨成活7例,成功率47%;旧术式组共进行手术8例,皮瓣成活4例,成功率50%,病理检测皮下髂骨成活3例,成功率37.5%,其中实验组动脉吻合时间(24.7±2.3)min,明显短于旧术式组(36.7±1.5)min(均P0.05),而静脉吻合时间、缺血时间,供受体准备时间并无差异(均P0.05)。结论:通过剥离供者臀大肌,改变动脉吻合对象,可以建立相对简单、稳定的髂骨皮瓣移植模型,为探索带血管骨髓移植诱导嵌合状态提供了新的动物模型。     

大鼠肾移植慢性排斥反应模型的建立

目的建立一种稳定的大鼠原位肾移植慢性排斥反应模型。方法供体为近交系F344大鼠,受体为Lewis大鼠,供肾采用左肾,在体修整,原位灌注。肾静脉用硬膜外导管做为临时内支架管端-端、六针法吻合,腹主动脉端-侧连续缝合,输尿管带膀胱瓣与膀胱吻合。受体术前3 d开始环孢素A灌胃至术后30 d（5 mg/kg·d）,以预防急性排斥反应。结果手术时间120～180 min;手术成功率90.9%（40P44）;受体均存活60 d。并发症有吻合口出血、静脉血栓形成、急性排斥反应等。结论供肾原位灌注,在体修整是简单可靠的方法。静脉內支架管端端吻合,腹主动脉端侧吻合能够达到稳定的成功率,值得推广。熟练的外科操作技能和血管吻合技术是手术成功的关键。     

Transplantation of both kidneys from one donor rat

We have developed a technique for harvesting and transplanting two kidneys from one donor rat. Our method involves end-to-end anastomosis of the renal artery and the renal vein. Because of the short distance between the caudal vena cava and the right kidney, renal transplantation is not feasible on the right side of the recipient. The right donor kidney was therefore transplanted to the left side. Graft morphology was assessed on paraffin sections. We observed no differences between conventionally transplanted kidneys (n = 116) and right kidneys transplanted according to the method described (n = 40). In conclusion, our technique is simple, saves time and reduces the number of donor rats.     

The advantages of end-to-side arteriovenous anastomosis over the other two types of arteriovenous anastomosis in dialysis patients

The functional duration of vascular access in dialysis patients depends on the emergence of threatening complications. Discussions are constantly being held in an attempt to discover their causality and decrease their emergence. In 260 patients undergoing haemodialysis, we have studied the potential existence of a cause-and-effect relation between the emergence of complications in the vascular access and the applied type of arteriovenous (av.) anastomosis in the arteriovenous (AV) fistula. We have observed the incidence of all complications, both that of the thrombosis incidence as well as the primary and secondary fistula patency (survival). The complications--The examinees with the end-to-end anastomosis showed the incidence of 8.08%, 6.15% of the patients with the end-to-side anastomosis and 7.31% of the patients with the side-to-side anastomosis. The differences regarding incidences are statistically significant (chi2-test = 29.25; P = 0.0001). Thrombosis--it has been found that thrombosis was the most frequent complication developing in 30.00% patients with the end-to-end av. anastomosis, in 2.31% patients with end-to-side av. anastomosis and in 5.56% patients with side-to-side av. anastomosis. The difference between the highest and the lowest assessment is 27.69%, and it is statistically relevant (chi2-test = 33.920; P = 0.0001). The primary patency (primary survival): within a 6-month interval following the establishment of vascular access, the first complications arose in 62.50% of patients with end-to-end av. anastomosis, 10.76% in those with end-to-side av. anastomosis and 18.88% in those with side-to-side av. anastomosis. The difference between the highest and the lowest assessment is 51.74%, which is statistically significant (chi2-test = 49.009; P = 0.0001). The secondary patency: 24 months subsequent to the establishment of vascular access, the AV-fistula was still functional in 52.50% of the patients with end-to-end av. anastomosis, 89.23% in those with end-to-side av. anastomosis and 81.11% in those with side-to-side av. anastomosis. The difference between the highest and the lowest assessment is 36.73%, which is also statistically significant (chi2-test = 26.579; P = 0.0001). According to our research, the end--to-side type of av. anastomosis in vascular access provides better results both in relation to the duration as well as the maintenance of the functionality of the Av-fistula and in the lower incidence of the complications than the other types, and hence it shows a definite advantage.     

Murine Cervical Heart Transplantation Model Using a Modified Cuff Technique

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice^1-3. This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates⁴.Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient⁵.Herein, we provide additional details of this technique to supplement the video.     

A Modified Method for Heterotopic Mouse Heart Transplantion

Mice are often used as heart transplant donors and recipients in studies of transplant immunology due to the wide range of transgenic mice and reagents available. A difficulty is presented due to the small size of the animal and the considerable technical challenges of the microsurgery involved in heart transplantation. In particular, a high rate of technical failure early after transplantation may result from recipient death and post-operative complications such as hind limb paralysis or a non-beating heart. Here, the complete technique for heterotopic mouse heart transplantation is demonstrated, involving harvesting the donor heart and its subsequent implantation into a recipient mouse. The donor heart is harvested immediately following in situ perfusion with cold heparinized saline and transection of the ascending aorta and pulmonary artery. The recipient operation involves preparation of the abdominal aorta and inferior vena cava (IVC), followed by end-to-side anastomosis of the donor aorta with the recipient aorta using a single running 10-0 microsuture and a similar anastomosis of the donor pulmonary artery with the recipient IVC. Following the operation the animal is injected with 0.6 ml normal saline subcutaneously and allowed to recover on a 37 °C heating pad. The results from 227 mouse heart transplants are summarized with a success rate at 48 hr of 86.8%. Of the 13.2% failures within 48 hr, 5 (2.2%) experienced hind limb paralysis, 10 (4.4%) had a non-beating heart due to graft ischemic injury and/or thrombosis, while 15 (6.6%) died within 48 hr.     

Rotational in vitro compliance measurement of diverse anastomotic configurations: a tool for anastomotic engineering

Anastomotic configurations with a small internal diameter are prone to intimal hyperplasia which can cause occlusion within weeks or months. A link between intimal hyperplasia and inhomogenities of the elastic profile of the anastomosis has been established, making anastomotic engineering directed towards smoothing the compliance profile at the anastomotic site essential. Methods to date restrict the anastomotic compliance measurement to one plane. We present a method by which the anastomotic configurations are rotated, thereby allowing an anastomotic elastic profile assessment in multiple planes. Eight end-to-end anastomoses (ovine common carotid artery) and three end-to-side anastomoses (e-PTFE graft to ovine common carotid artery) were prepared and mounted in an artificial circulation system. Anastomotic circumferential compliance (maximal-minimal diameter/(maximal-minimal pressure.minimal diameter)) was measured by means of a laser-scan-micrometer and a Statham pressure transducer. By rotating end-to-end anastomoses, the compliance was measured in three, and in end-to-side anastomoses in four different planes. Multiplanar compliance variability in areas remote to both end-to-end and end-to-side anastomoses was approximately 9%. At the suture line the variability was approximately 22% in end-to-end anastomoses and 78% in end-to-side anastomoses. These results show that local factors result in different compliance profiles when utilizing a multiplanar technique, particularly in end-to-side anastomoses. The rotational apparatus is a tool which can be used to more accurately engineer a homogeneously compliant anastomosis, with the ultimate goal of prolonging anastomotic patency.     

大鼠异位工作型心脏移植模型的建立

目的 建立大鼠腹腔异位工作型心脏移植动物模型.方法 Wistar大鼠30只,将供心主肺动脉与左房吻合,再将供心移植到受体腹部,将升主动脉与供心腹主动脉端侧吻合,使得左心房获得前负荷,成为工作型心脏.结果 成功建立大鼠腹腔异位工作型心脏移植模型,15例成功11例,手术成功率为73%.手术平均时间为(38.8±5.7)min.移植心脏获得长期存活,在28 d后通过超声观察可见供体心脏工作正常.结论 手术的关键是提高供心的摘取技术及受体的血管吻合技术,同时术后给与供心适当的按摩辅助也非常必要.此模型可以更好的用于移植免疫学的研究.     

A microdissected thin tensor fasciae latae perforator flap.

A new method, named "microdissection," has been introduced to create a thin flap by elevating the tensor fasciae latae perforator flap to serve as microdissected thin tensor fasciae latae perforator flap. In microdissection, perforators that run in the posterolateral direction in the adipose tissue after penetrating the deep fascia are dissected meticulously using an operative microscope, and a thin flap is elevated in a single process. The caliber of the perforator artery and vein in the tensor fasciae latae muscle measures approximately 0.7 mm and 0.9 mm, respectively. When transplanting the flap, an end-to-side anastomosis to the main artery measuring 1 to 2 mm is preferable to avoid the risk of arterial thrombosis. In contrast, an end-to-end anastomosis of the perforator vein to the comitans vein of the main artery can be performed safely. In the present study, 11 flaps were transplanted to the sites of skin defects of the neck, hand, axilla, knee, and foot. The author considers that the first clinical indication of this flap is reconstruction of hand skin defects.     

Conservation of major leg arteries when used as recipient supply for a free flap.

The potential hazards of using proximal segments of leg arteries for end-to-end anastomosis to vessels in free flaps are examined, and alternatives are proposed. The convservation of the major tibial arteries seems highly desirable, to minimize any subsequent development of ischemic complications. Turning a free flap upside down moves the anastomosis to the distal part of the extremity, thus conserving most of the muscular branches of the recipient artery. Cutting the recipient artery distally and bending it back in recurrent fashion also allows for easy end-to-end anastomosis, with many technical advantages.     

A triangular cutting arteriotomy scissors facilitating end-to-side anastomoses.

A new microsurgical triangular cutting scissors facilitating end-to-side anastomoses has been developed. The instrument removes oval pieces of tissue from the vascular wall with a single cut. This has several advantages over conventional double cuts with straight microscissors. Preferential use of end-to-side anastomoses has been advocated by several authors, one of the main reasons for this being preservation of the distal blood flow in the artery used in the recipient bed. It also has been reported that vascular occlusions are less frequent with this type of coupling. Another important indication for end-to-side anastomoses is a significant discrepancy in vessel size. One of the more demanding tasks in making an end-to-side anastomosis is the performance of a perfect arteriotomy. With the aim of facilitating the arteriotomy in end-to-side anastomoses, a new microsurgical instrument has been developed.     

Renal transplantation in the rabbit: a model for preservation studies.

Transplantation is necessary for evaluation of kidney preservation procedures, and a model using a small laboratory animal is desirable. The rabbit was found to be a suitable animal for this purpose. Even long periods of anaesthesia without artificial respiration were safely achieved. Hydration and serum electrolytes could be maintained within normal ranges with intravenous injections of isotonic saline and dextrose during and after the operation. The kidneys were implanted by anastomosing the artery and vein end-to-side to the abdominal aorta and the posterior vena cava respectively. The ureter was implanted into the bladder over a nylon stent. In a recent 100 transplantations the incidence of vascular thrombosis was low (4%), but rather more (10%) mainly late ureteral complications were encountered. Transplanted kidneys showed good function with mean peak serum creatinines of 285 mumol/l and normal macroscopic and histological appearance at autopsy.     

Orthotopic Aortic Transplantation in Mice for the Study of Vascular Disease

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. This is largely true, but there are a number of important principles that can reduce the difficulty of these procedures and enhance reproducibility. Orthotopic aortic transplantation is an excellent procedure in which to learn these principles because it involves only two end-to-end anastomoses, but requires good suturing technique and handling of the vessels for consistent success. This procedure begins with the procurement of a length of abdominal aorta from a donor animal, followed by division of the native aorta in the recipient. The procured aorta is then placed between the divided ends of the recipient aorta and sutured into place using end-to-end anastomoses. To accomplish this objective successfully requires a high degree of concentration, good tools, a steady hand, and an appreciation of how easily the vasculature of a mouse can be damaged, resulting in thrombosis. Learning these important principles is what occupies most of the beginner''s time when learning microsurgery in small rodents. Throughout this protocol, we refer to these important points. This model can be used to study vascular disease in a variety of different experimental systems^1-8. In the context shown here, it is most often used for the study of post-transplant vascular disease, a common long-term complication of solid organ transplantation in which intimal hyperplasia occurs within the allograft. The primary advantage of the model is that it facilitates quantitative morphometric analyses and the transplanted vessel lies contiguous to the endogenous vessel, which can serve as an additional control⁹. The technique shown here is most often used for mice weighing 18-25 grams. We have accumulated most of our experience using the C57BL/6J, BALB/cJ, and C3H/HeJ strains.     

Comparison of vascular hemodynamics in experimental models of microvascular anastomoses

Blood flow was measured in the canine saphenous artery using electromagnetic flowmetry. Significant increase in blood flow was noted after occlusion of the distal femoral artery. However, after raising a saphenous island flap there was no significant change in the blood flow before and after distal femoral artery occlusion. The flap peripheral resistance and blood flow were compared after end-to-end and end-to-side anastomosis and no statistical difference was noted.     

兔颈动、静脉移植桥血管狭窄模型的建立及其电镜观察

目的：建立兔颈动、静脉移植血管桥动物模型,观察移植桥血管内膜增生和狭窄的电镜下表现。方法：通过兔双侧颈动脉进行动脉桥和静脉桥的移植,形成双侧移植血管桥再狭窄动物模型。在第8周施行血管桥移植手术的同时留取右侧颈动静脉标本作为对照血管,再分别于第12周、16周和第20周分别处死模型兔,采集移植桥血管标本,在光镜下测量其内膜厚度、面积、狭窄度,并进行电镜观察。结果：颈动脉和颈静脉桥移植后,随着时间的延长,桥血管的出现平滑肌迁移,脂质沉积,内膜增生,血管狭窄等改变,且以静脉桥血管的病理改变更为明显。结论：在兔形成动脉粥样硬化病变基础上,进行双侧颈动脉血管桥的移植,建立兔双侧颈动脉移植血管桥再狭窄动物模型,有利于设立自身对照,研究术后动静脉桥再狭窄差异机制;建立动、静脉桥后,位于血管中膜的平滑肌细胞出现向血管内膜迁移现象,说明中膜平滑肌细胞迁移进入内膜导致新内膜形成是血管再狭窄的重要环节。     

Anorectal Transplantation in Human Cadavers: Mock Anorectal Allotransplantation

Background

Anorectal transplantation is a method for patients who have lost their anorectal function or suffer from congenital anorectal dysfunction to recover this function, and this has been investigated in experimental animal models using pigs, dogs, and rats. In this study, we performed an examination of anorectal transplantation in human cadavers to investigate whether this procedure could be performed in patients.

Methods

A 77-year-old woman cadaver 1 was used as the donor and a 98-year-old woman cadaver 2 was used as the recipient. Initially, abdominoperineal excision of the anus and rectum (the Miles’ operation) was performed on the recipient. Next, an anorectal graft containing the pudendal nerve (PN), pudendal artery (PA), pudendal vein (PV), inferior mesenteric artery (IMA), and inferior mesenteric vein (IMV) was harvested from the donor. The donor graft was transplanted into the recipient by intestinal anastomosis and microneurovascular anastomoses orthotopically.

Results

The diameters of the PN (right/left), IMA, and IMV were 2.5 mm/2.5 mm, 2.0 mm, and 1.5 mm, respectively, in cadaver 1, and 2.0 mm/2.0 mm, 2.0 mm, and 2.0 mm, respectively, in cadaver 2. The length of the PN, PA, PV, IMA, and IMV in the graft was sufficient to allow proper anastomosis.

Conclusion

This preliminary study indicated that human anorectal transplantation was possible anatomically and technically. We anticipate our study will aid in the potential future application of this procedure to human patients.     

Heterotopic vascularized murine cardiac transplantation to study graft arteriopathy

The development of microsurgical techniques has facilitated the establishment of fully vascularized cardiac transplantation models in small mammals. A particularly useful model that has evolved for the study of cardiac allograft vasculopathy (CAV) is a heterotopic (abdominal) vascularized murine cardiac transplantation model. Using this model has permitted the elucidation of genetic, immune and non-immune factors contributing to the development of this inexorable pathological condition, which compromises half of all human cardiac transplants. This protocol details methods for performing the transplant, histomorphometric assessment of the graft vasculature and functional evaluation of the transplanted heart. In experienced hands, the surgical procedure requires approximately 75 min to complete, and vasculopathy results are obtained at 2 months. This model entails a fully vascularized implantation technique in which the donor ascending aorta and pulmonary artery are sutured end-to-side to the recipient abdominal aorta and inferior vena cava, respectively. As this model reliably reproduces immunological and non-immunological features of CAV, investigators can thoroughly explore contributory mechanisms, diagnostic modalities and therapeutic approaches to its mitigation.