End-to-end anastomosis between two vessels of different size

A technique enabling end-to-end anastomosis between two vessels of different size is described. This method reduces the larger vessel to a truncated cone by excision of a triangle the base of which corresponds to a part of its circumference. By this method, the diameters are easily adapted to one another and the end-to-end anastomosis remains centred.     

Experimental microvascular sleeve anastomosis in size discrepancy vessels

Anastomosis in vessels of different caliber may predispose to irregularities and thrombosis. Techniques have been described to manage the discrepancy such as mechanical expansion, end to side anastomosis, oblique cut, sleeve procedure, mechanical devices, grafts, adhesives and glues. We performed sleeve anastomosis introducing the superficial inferior epigastric artery (SIEA) into the femoral artery of 20 Wistar rats. Permeability, endothelialization and anastomosis remodeling was assessed. Although slight narrowing of the anastomosis was found in 30% of cases, 100% permeability was achieved and endothelialization was completed in the second week. We conclude that the sleeve procedure is a reliable method to manage SIEA discrepancies in microvascular anastomosis.     

Sutureless microvascular anastomosis using a neodymium-yag laser

A technique is described in which a Neodymium-YAG laser is used to anastomose arteries 0.8 to 1.0 mm in diameter. Heat generated by the laser causes fusion of the collagen of the media, making direct handling of the vessel wall unnecessary. Four variations of the technique were performed in 120 rat carotid arteries. Angiographic and scanning electron microscopic studies were carried out immediately after surgery and at intervals of 1 day to 6 months after anastomosis. Patency rates as high as 92.5% were recorded. The technique that produced the most secure anastomosis was considered to be one in which a vascular strut was used as an aid in apposition, followed by the application of a piece of vein wall to the anastomosis with tissue adhesive. The main advantages of the laser technique are speed and consistency. Complications such as disruption and aneurysm formation are considered to be rare.     

End-to-end anastomosis by enclosure between a prosthesis and a vessel with a significant difference in diameter

A technique is described that allows an end-to-end anastomosis between a vascular prosthesis and a vessel that is much smaller in diameter. This procedure involves enclosing the prosthesis and the vessel while keeping the vascular axis straight without any kinking. In addition, this technique makes little demand on the extensibility of the natural tissue in order to adapt to the prosthesis, which is inextensible.     

The effect of stasis on a microvascular anastomosis

An experiment was done in rats to determine the effect of stopping the flow of blood across a fresh anastomosis. It was found that brief periods of stasis, up to 30 minutes, caused a minimal increase in the rate of thrombosis, but 60 minutes of stasis caused a significant risk of thrombosis in both arteries and veins. The thrombosis associated with stasis could be prevented by the systemic administration of heparin.     

Flow recovery and vasoconstriction following microvascular anastomosis

A variety of factors may limit blood flow recovery in free flaps. In this study one of these factors, vasoconstriction, and its consequences was investigated. Blood flow recovery at the skin level following microvascular anastomosis was evaluated in the rat orthotopic groin free flap model using a laser Doppler velocimeter. In a study of 41 rats, measurements of external vessel diameter were made using a standard machinist's drum micrometer. After each flap was raised and the anastomoses performed, the field was flooded with either saline, 2% lidocaine, or 0.75% bupivacaine (Marcaine). The vascular clamps were released and measurements of flow were recorded as a percentage of the control value. In the saline-control group, it was found that flow gradually recovered to 91% of the preoperative value in an average time of 5.7 minutes. Six of 12 vessels in this group were found to have measurable spasm of the pedicle. In the lidocaine-treated group, flow recovered to 93% of the preoperative value in an average of 5.0 minutes. Two of 15 vessels had measurable spasm. In the Marcaine-treated group, flow recovered to 94% of the preoperative value in an average of 5.1 minutes. Three of 14 vessels showed measurable spasm. The final level of flow recovery showed no statistical difference in any of these groups whether or not spasm was present. We therefore conclude that, in this model, alteration in the diameter of the vascular pedicle as a consequence of performing a microvascular anastomosis affects only the time it takes to achieve ultimate recovery of flow but does not affect its final level.     

小血管端侧吻合新方法

吻合血管的游离组织移植的成功率，主要取决于小血管吻合的通畅率，端端吻合技术是常用的小血管吻合技术，但是，端侧吻合与其相比，由于吻合后发生血管痉挛较低，组织供血量大。2006年以来，我们采用Sen等介绍的菱形端侧小血管吻合技术，取得满意效果，现介绍如下。     

Successful replantation of a bitten-off nose by microvascular anastomosis

A case is presented of a nose bitten off by a dog and successfully replanted by artery-to-artery and artery-to-vein anastomosis. In the absence of vein-to-vein anastomosis, the clinical course suggested that artery-to-vein anastomosis was useful for venous drainage, although the extent to which this contributed to the survival is not known.     

Coupled suturing: a new technique for microvascular anastomosis

The left carotid artery of 12 Sprague-Dawley rats was sectioned and anastomoses immediately performed utilizing a new technique termed coupled suturing. Patency and constriction were assessed immediately postoperatively and at 1, 2, and 3 weeks. Specimens were also evaluated by light microscopy and scanning electron microscopy. Vessels healed well with excellent patency and edge eversion. With the development of a specialized needle, coupled suture could prove to be a reasonable alternative to current methods of anastomosis. Its main advantage is better intimal eversion, which decreases the risk of thrombosis.     

Vascular diameter determining the magnification for a microvascular anastomosis

The purpose of this study was to determine the association between vascular diameters and amount of magnification and to assess the influence of the magnification media on the microanastomosis quality and permeability. Sixty arterial microanostomoses were distributed into three groups: group I (diameter 1.5 mm), group II (1.5 to 2.5 mm), and group III (> 2.5 mm). The models used were carotid artery of Sprague-Dawley rats and carotid and abdominal artery of wild rabbits. In each group, 10 anastomoses were performed with 2.5 x loupes and 10 with 10 x microscope. The total time of anastomosis, the quality of the anastomosis (Gorman scale), and 24-hour permeability rate were measured. The total anastomotic time and quality had statistical differences for the microscope by analyzing the total sample and group I only. The global permeability was 83% for the microscope and 40% for the loupe. The same result was observed in group I but no differences were observed in the other groups. The histology and the survey showed similar results. Microanastomoses performed under a microscope (10 x) were performed in less time, were of better quality, and had higher permeability rates when compared with those performed under a loupe (2.5 x). In vessels < 1.5 mm, these differences were statistically significant but in vessels > 1.5 mm no differences were observed.     

Use of a tilted double clamp in microvascular anastomosis

A tilted or angulated double microvascular clamp is described that, when applied to the vessels to be anastomosed, presents the vessel ends angulated upward facing the surgeon, so that the initial suturing of the posterior wall can be completed without rotating the vessel. Such a clamp is valuable in clinical situations where space is limited and where conventional double clamps cannot be rotated in the usual fashion.     

Re-use of the recipient vessels of a microvascular transplant

Three cases are described in which a second microvascular free flap, transplanted after a delay of several months, was provided perfusion by re-using the recipient vessels of the first flap in end-to-end fashion. In each patient healing of the second flap was uneventful, and both transplants continue to survive. Prior to harvesting the second transplant, a careful intraoperative examination was performed in which the vascularity of the original transplant was assessed. In each case, recipient vessel re-use represented the least risky of several options. The results of the present series suggest that vascularization from the transplant bed or surrounding tissues proceeds despite the fact that, initially, the only source of blood for the free flap flows through a single axial vessel. This single vessel can therefore be divided without loss of the transplant as long as the transplant bed has already provided vascularization to the flap. In our opinion, the timing of the second procedure and the quality of the transplant bed are the key factors in the survival of the transplants.     

Fibrin glue application in microvascular anastomosis: comparative study of two free flaps series

Background: Since the first experiments with fibrin glue application in microvascular anastomoses in 1977, several studies have reported its benefits on suture reduction and anastomosis decreased time. In spite of that, clinical experience has been limited to two neurosurgical and two replantation case series, all of them with good results. This study was conducted to evaluate the feasibility and the potential benefits of fibrin glue application in free flaps. Methods: We performed 24 free flaps in 24 patients, from March 2005 to June 2006. Twenty were included in this study. They were divided into two groups according to the anastomosis technique: conventional group (n = 7 patients) and fibrin glue group (n = 13 patients). In the conventional group, the anastomosis was performed with interrupted sutures, whereas in the fibrin glue group, they were performed using less sutures and fibrin glue application. Results: The application of fibrin glue cut by half the number of sutures required to complete the anastomoses. The mean arterial and venous anastomotic times in the conventional group were 27.2 and 24.0 minutes, respectively. In the fibrin glue group, they were 13.6 and 12.6 minutes, respectively. All these differences were statistically significant. There was no significant difference of ischemic time between two groups (P = 0.26). The survival rate of the flaps was similar in both groups: 84.6% (11 of 13) in the fibrin glue group and 85.7% (6 of 7) in the conventional group (P = 1.0). Conclusions: Fibrin glue application in free flaps was feasible and allowed us to complete the anastomoses with fewer sutures and less time. The survival rate of the flaps was not adversely affected by the fibrin glue. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009.     

Vessel anastomosis using a venous cuff and two sutures: an experimental study in rat femoral and epigastric vessels

Using rat femoral and epigastric vessels, the efficacy of an autogenous venous cuff and reduction in the number of required sutures were examined. Cut vessels were anastomosed with two sutures using 11-0 nylon, and the anastomotic site was covered with a venous cuff. After two weeks, the patency of the anastomosed vessels was evaluated. Although results in large-caliber femoral veins were poor, the femoral arteries and epigastric vessels demonstrated high patency rates. In microscopic and scanning electron microscopic evaluations, gaps and depressions between sutures were observed, but they were smoothly covered by endothelium. These results suggest the usefulness of the venous cuff in microvascular surgery, especially in anastomosing fine-caliber vessels.     

Combined microvascular anastomosis: experimental and clinical experience

A short operative time and a high successful rate of microvascular anastomosis are the goals of many plastic surgeons. The authors present their experimental and clinical experience in microvascular anastomoses with the use of a combination of continuous suture and interrupted tie. Twenty rats were divided into two groups. The aorta and inferior vena cava were used for microvascular anastomoses. The vessels of 10 rats were repaired with conventional interrupted suture, and the vessels of the other 10 rats were repaired with combined anastomoses. A total of 150 clinical microvascular surgeries during the past 2 years are also presented, all of which were performed using the combined method. Microvascular anastomoses with the combined method were completed faster than when using the conventional interrupted method in experimental studies. Clinically, no direct microvascular anastomosis failed with the use of combined method. Microvascular anastomosis with the use of the combined continuous suture and interrupted tie resulted in satisfactory outcomes. This technique has the advantages of both interrupted and continuous methods, but not their shortcomings.