The venous flap - a safe alternative to the simple vein graft in a special situation.

The use of free tissue transfer has evolved to become the mainstay of treatment of tissue defects. The reconstructive surgeon can choose from a wide variety of flaps. Flaps are chosen based on the tissue defect and also on the characteristics of the pedicle in terms of calibre and vessel length. Occasionally situations arise necessitating the use of vein grafts. Vein grafts can be used primarily as part of a planned procedure to increase pedicle length or as a salvage technique following anastomotic complication. We report the use of venous flap instead of a conventional vein graft, for restoring continuity of the arterial flow in the pedicle of a free flap, following resection of a thrombosed segment. A venous flap harvested from the left leg with a cutaneous vein was used in a flow-through fashion to restore the continuity of the arterial inflow to the flap. The venous flap is an ideal option in selected cases instead of a vein graft. This is specifically indicated where there is a shortage of soft tissue to cover the anastomosis. The pedicle can then be covered in a tension-free manner. Thus in addition to extremity wounds, the venous flap can be used safely in salvage of difficult situations in the head and neck area.     

Role of the perforating vein in vascular pedicle of free forearm flap

An innovation in the preparation of the vascular pedicle of the free radial forearm flap is presented. While the radial artery is commonly used as the arterial pedicle of the flap, either the cutaneous venous system or the radial comitant vein (deep venous system) is used as the venous pedicle. The perforating vein communicates between these two venous systems at the cubital fossa, and we confirmed its presence in all but one of more than 180 cases. When the vascular pedicle is dissected proximally to the perforating vein contained in the flap, the venous drainage of both the deep and cutaneous systems can be restored by anastomosis of only one vein: the cutanous or the radial comitant vein. On the other hand, the flap can be raised with the radial vessels (without the cutaneous vein) at the start of surgery, and a large caliber cutaneous vein, such as the median cubital, the cephalic, or the basilic, can be used for anastomosis in cases where the cutaneous veins in the distal forearm are too thin, or where the radial comitant vein is composed of two thin separated veins. We believe that preserving the perforating vein would make the forearm flap more reliable and more convenient in reconstructive surgery. © 1995 Wiley-Liss, Inc.     

Donor graft outflow venoplasty in living donor liver transplantation.

Hepatic venous outflow reconstruction is a key to successful living donor liver transplantation (LDLT) because its obstruction leads to graft dysfunction and eventual loss. Inclusion or reconstruction of most draining veins is ideal to ensure graft venous drainage and avoids acute congestion in the donor graft. We developed donor graft hepatic venoplasty techniques for multiple hepatic veins that can be used in either right- or left-lobe liver transplantation. In left-lobe grafts, venoplasty consisting of the left hepatic vein and adjacent veins such as the left superior vein, middle hepatic vein, or segment 3 vein is performed to create a single, wide orifice without compromising outflow for anastomosis with the recipient's vena cava. In right lobe graft where a right hepatic vein (RHV) is adjacent with a significantly-sized segment 8 vein, accessory RHV, and/or inferior RHV, venoplasty of the RHV with the accessory RHV, inferior RHV, and/or segment 8 vein is performed to create a single orifice for single outflow reconstruction with the recipient's RHV or vena cava. Of 35 venoplasties, 2 developed hepatic venous stenoses which were promptly managed with percutaneous interventional radiologic procedures. No graft was lost due to hepatic venous stenosis. In conclusion, these techniques avoid interposition grafts, are easily performed at the back table, simplify graft-to-recipient cava anastomosis, and avoid venous outflow narrowing.     

Serratus anterior venous tributary as a second outflow vein in latissimus dorsi free flaps

The latissimus dorsi (LD) flap is a large and reliable myocutaneous flap with a consistently long vascular pedicle. However, the limitation of the thoracodorsal pedicle is that it has only one draining vein for anastomosis. We describe a simple technique of recruiting the tributary vein to the serratus anterior and using it as a second draining vein to alleviate congestion in lower limb reconstruction. The serratus anterior venous tributary segment is cut back to an avalvular segment which averages 5 mm in length. Provision of an additional venous outflow to the flap enabled a second venous anastomosis to the short saphenous vein (N = 1), the long saphenous vein (N = 2), a deep vein (N= 1), and to a deep vein via a vein graft (N = 1), respectively. Five patients with degloving injury of the lower extremity of sizes 150 cm(2) (10 × 15 cm) to 260 cm(2) (10 × 26 cm) underwent successful reconstruction using the LD muscle flap with the serratus anterior tributary vein as a second outflow vein. This serratus anterior venous tributary serves as a useful second outflow channel for alleviating venous congestion during lower limb reconstructive surgery and should be routinely preserved as a lifeboat.     

Hepatic venoplasty in living-donor liver transplantation using right lobe graft with middle hepatic vein

Inclusion of the middle hepatic vein in a right lobe graft from a living-donor may improve venous drainage and avoid graft dysfunction, but reconstruction of the middle hepatic vein is technically difficult. We developed a hepatic venoplasty technique, which was applied in eight consecutive right lobe liver transplantations. The right and middle hepatic veins of the graft were joined together to form a triangular cuff for a single anastomosis to the recipient's inferior vena cava. Hepatic venoplasty was successful in all cases, and no interposition graft was required. Venovenous bypass was not used. All grafts showed immediate function, and no hepatic venous outflow obstruction was observed. There was no reoperation and the graft survival rate was 100%. This hepatic venoplasty technique can be applied systemically as a standard one in right lobe liver graft with the middle hepatic vein to simplify the recipient hepatectomy and to obviate venous outflow obstruction.     

Use of stretch expanded polytetrafluoroethylene as a microvascular graft in a low-pressure situation

OBJECTIVE: Microvascular reconstruction is often limited by the availability and length of the pedicle. The harvesting of autologous vein grafts adds morbidity and may not provide a good match. Expanded polytetrafluoroethylene (ePTFE) grafts have been used routinely in macrovascular surgery. However, there are no conclusive data on the performance of small-diameter PTFE grafts for pedicle lengthening in free flaps in a low-pressure situation. In this study, we evaluated the efficacy of 3-mm diameter stretch ePTFE grafts to lengthen the venous pedicle of a free flap. METHODS: Fifteen male New Zealand white rabbits were operated on under sterile conditions. Using an operating microscope, an epigastric flap was raised and the pedicle was exposed and dissected to its origin from the superficial femoral vessels. A segment of the vein of 1 cm to 3 cm was replaced with a stretch ePTFE graft. Microsurgical anastomoses were performed using 9-0 nylon sutures. Four weeks postoperatively, the flaps were raised again with the pedicles re-explored. The graft was then removed and examined histologically. RESULTS: All the grafts demonstrated immediate patency. There were no cases of flap loss on the control side at 4 weeks postoperatively. When re-explored, the patent ePTFE grafts appeared to be covered by connective tissue. Light microscopy showed neoendothelialization with fibrovascular in growth. CONCLUSION: From this study, we can conclude that 3-mm diameter stretch ePTFE grafts can be used successfully as an alternative to bridging autologous vein grafts in free-flap pedicles.     

Outflow reconstruction in right hepatic live donor liver transplantation

BACKGROUND: Inconstant venous anatomy increases the risk of outflow complications in right hepatic live donor liver transplantation (RH-LDT), but no consensus has emerged guiding optimal reconstruction for venous outflow. METHODS: We retrospectively analyzed surgical venous reconstruction using a flexible approach to anterior accessory veins in 48 RH-LDTs performed between April, 1998 and July, 2002. RESULTS: Actuarial recipient graft and patient survival was 79% and 85%, respectively. Single hepatic venous anastomosis was performed in 74% of the patients. Twelve patients underwent reconstruction of 20 accessory veins, including 7 posterior segment veins and 13 anterior segment veins. Anterior vein reconstruction techniques included end-to-end anastomosis to the middle hepatic vein, interposition conduit, venoplasty, or a combination of techniques. Documented complications related to the venous anastomosis occurred in only 1 patient (2%), with no patient having a documented venous thrombosis of either the main RHV or a reconstructed accessory vein. There were no differences in outcome based on single versus multiple venous reconstruction. Anteromedial congestion was noted in 3 patients in the absence of anatomic venous anastomotic complication, but the clinical significance of this finding is unclear. CONCLUSIONS: Despite variations in segmental venous drainage and a propensity for anteromedial congestion in right hepatic grafts, RH-LDT can be performed without outflow obstruction with close attention to a wide RHV anastomosis. In addition, anterior accessory vein reconstruction can be reserved for grafts of marginal size or quality where early postoperative venous congestion may impair early graft function. Routine extended hepatectomy incorporating the MHV with the graft is unnecessary.     

The basilic vein: an alternative drainage of DIEP flap in severe venous congestion

The deep inferior epigastric perforator (DIEP) flap has become a major advance in autologous breast reconstruction, offering all the advantages of free TRAM flap with less donor-site morbidity and postoperative pain. The major drawback threatening the DIEP flap procedure is venous congestion, with potential partial or complete flap loss. Many authors reported different surgical tips aiming to solve this setback, including secondary anastomosis of deep inferior superficial epigastric vein with alternative venous outflow vessels. We present a case report of a DIEP flap salvaged by an alternative venous anastomosis, after comitant veins of the primary anastomosis widely thrombosed a few hours postoperatively. A venous bypass using ipsilateral basilica vein and superficial inferior epigastric vein was fashioned.     

Renal transplantation with venous drainage through the superior mesenteric vein in cases of thrombosis of the inferior vena cava

Renal transplantation usually is performed by placing the graft in the iliac fossa, anastomosing the renal vein to the iliac vein or, when this is not possible, to the vena cava. When vascular complications occur, particularly on the venous side, the position of the graft may have to be changed. This report describes orthotopic renal grafts and positioning of the organ with anastomosis to the splenic vessels. Venous drainage was established directly into the mesenteric-portal territory, with two cases to the portal vein and one to the inferior mesenteric vein. A new technique for the venous drainage of the renal graft is shown. We have used this model in two cases of infrarenal inferior vena cava thrombosis. The kidney was located in a retroperitoneal position, with venous drainage to the superior mesenteric vein through an orifice in the posterior peritoneum.     

Alternatives to the double vena cava method in partial liver transplantation.

Minimizing graft congestion in partial liver transplantation is important, especially when the graft weight is marginal for the recipient metabolic demand. We prefer the double vena cava technique for reconstructing middle hepatic vein tributaries with thick, short hepatic veins because the technique can reduce the warm ischemic time of the graft and make a wide anastomosis. This technique requires a cryopreserved superior or inferior vena cava. We devised an alternative double vena cava method using iliac or femoral vein grafts and applied it to two right liver transplantation patients. There was no postoperative hepatic venous outflow block in either patient. In conclusion, application of this technique, even in the absence of a suitable vena cava, can help to minimize graft congestion.     

Easy venous superdrainage in DIEP flap breast reconstruction through the intercostal branch

The deep inferior epigastric perforator (DIEP) flap has been shown to be a valid option for breast reconstruction, as it has certain advantages over the free TRAM flap, including lower morbidity in the donor area, conservation of abdominal wall function, and reduced postoperative pain. However, some cases of venous congestion in using the DIEP flap have been described. The authors present a case in which the venous return in a DIEP flap objectively (by measurement with a flux meter) presented a marked improvement (from 4 ml/min to 13.9 ml/min) after venous drainage was increased by means of the supplementary anastomosis of a comitant vein from the deep inferior epigastric pedicle to the intercostal branch of the internal mammary vein. The preservation of this branch is a simple and effective technique to improve the venous drainage of DIEP flaps, whether signs of congestion are present or not.     

成人间活体肝移植的手术技术改进(附13例报告)

目的探讨成人间活体肝移植的手术技术改进.方法2005年3-6月,施行了13例成人间右半肝活体肝移植,其中1例接受了2个左半肝,另1例接受了1个活体右半肝,1个尸体左半肝,术中采用了改良的手术技术,包括右肝静脉的重建,肝中静脉分支的搭桥,肝动脉搭桥及胆道吻合的改进.结果全组供体无严重并发症及死亡,受体发生并发症4例,包括肝动脉栓塞,胆漏,右膈下脓肿及肺部感染各1例,1例再移植因术后肺部感染,导致多器官衰竭（MOF）死亡.13例中除右肝静脉与下腔静脉（IVC）直接吻合,5例加行右肝下静脉重建,另5例采用自体大隐静脉搭桥行肝中静脉分支与IVC重建,保证了右肝的流出道通畅.移植物与受体重量比（GRWR）为0.72%至1.24%,其中9例＜1.0%,2例＜0.8%,无小肝综合征发生.结论采用了改进的手术技术,特别是肝静脉流出道的充分重建可有效避免小肝综合征,从而使活体右半肝移植成为相当安全的手术.     

The effect of a venous anastomosis Tyrell vein collar on the primary patency of arteriovenous grafts in patients undergoing hemodialysis

PURPOSE: Vein collars and patches are used at the distal anastomoses of infrainguinal prosthetic grafts to improve graft patency. We initiated a randomized, prospective study to determine whether a Tyrell vein collar at the venous anastomosis of forearm loop arteriovenous grafts (AVGs) would improve patency. METHODS: Patients who required new forearm AVGs were randomized to (1) a standard end-to-side graft-vein anastomosis (control group) or (2) a Tyrell vein collar between the graft and the vein (study group). End points were (1) graft thrombosis, (2) graft removal and ligation, or (3) inadequate graft function. Randomization of 75 subjects was planned. The study was terminated early for ethical reasons. RESULTS: Seventeen patients (eight men, nine women) with a mean age of 52.8 years (range, 31-79 years) had 17 grafts placed (control group, n = 10; study group, n = 7). Comorbidities were not different between the groups (P>.05). Six (86%) of seven study grafts failed by 9 months (mean, 4.6 months). Four (66%) failed study grafts had venous outflow tract stenosis from intimal hyperplasia. This was confirmed at surgery in three and by angiography in one. The 9-month primary patency was 80% for the control group versus 17% for the study group (P =.015). Smaller outflow vein diameter in the study group (P =. 048) did not account for this inferior graft patency. CONCLUSION: A Tyrell vein collar at the venous anastomosis of a forearm AVG resulted in premature graft failure. The use of a Tyrell vein collar may accelerate venous anastomosis intimal hyperplasia.     

Evolution of anterior segment reconstruction after live donor adult liver transplantation: a single-center experience

Controversy exists regarding the best method for venous outflow reconstruction after live donor liver transplantation using right lobe grafts. Some authors advocate routine inclusion of the middle hepatic vein with the graft, whereas others favor a more selective approach. In this report, we examine the evolution of our decision making and technique of selective anterior venous segment reconstruction during live donor adult liver transplantation performed in 226 recipients. We have developed a simplified back-bench procedure using sequential-composite anastomosis using various vascular conduits with syndactylization to the right hepatic vein creating a single large-outflow anastomosis in the recipient. Conduits used include iliac artery or vein allograft, recanalized umbilical vein, cryopreserved iliac artery allograft, and 6-mm synthetic expanded polytetrafluoroethylene vascular graft. This technique can be performed quickly, safely, and under cold storage conditions and results in excellent outcome while minimizing donor risk.     

Free transfer of the radial forearm flap with preservation of the radial artery

One of the main disadvantages of the radial forearm flap is the sacrifice of a major artery. To overcome this drawback the authors describe a technique of free transfer of the flap with preservation of the radial artery. The flap is elevated as a distal row perforator-based fasciocutaneous flap with a very short segment of the radial artery included in the inverted-T-shaped arterial pedicle. The venous outflow of the flap is provided by the cephalic vein, with accompanying veins of the radial artery left behind. Although the donor radial artery is repaired primarily, the flap is transferred to reconstruct a soft-tissue defect resulting from the release of a neck contracture after radiotherapy in a 42-year-old patient who had previous excision of a mandibular osteosarcoma. The arterial anastomosis was performed end to end between the superior thyroid artery and one limb of the arterial pedicle, with the other limb ligated. The venous anastomosis was performed end to end between the cephalic vein and the external jugular vein. The flap survived completely and a satisfactory result was obtained. The radial artery is demonstrated to be patent long after surgery, both with Allen's test and with a Doppler examination. Considering the possible sequelae of the sacrifice of the radial artery, this technique is obviously advantageous to such patients, even with a nonsatisfactory preoperative Allen's test. This perforator-based radial forearm flap is very easy to raise and to transfer, with anastomoses of large-diameter vessels.     

Hepatic vein reconstruction in ex situ split-liver transplantation

BACKGROUND: Anatomy of the left hepatic vein (LHV) was studied in a series of 53 consecutive cadaveric liver grafts that were divided for transplantation. METHODS: All divisions were performed ex situ and provided a left split graft with only the LHV as the hepatic outflow. The anatomy was categorized into three types: (A) single LHV trunk, (B) two veins closely merging toward the median hepatic vein, or (C) a double outflow. RESULTS: Direct implantation of the graft was performed in type A and was possible in type B after simple plasty of the ostia to create a single orifice. In type C, a venous jump graft could be interposed at bench work to allow direct anastomosis into the recipient. There were no related complications, except one type A case with late outflow obstruction. CONCLUSION: Liver division can be performed safely in liver grafts with variant LHV anatomy, if appropriate techniques for reconstruction are used. Also ex situ liver division has the advantage of allowing a detailed anatomic evaluation before dividing LHV: reconstruction can be performed ex situ, allowing a single-step direct anastomosis in the recipient, thus shortening suturing time.     

Bypass of superior vena cava. Fifteen years' experience with spiral vein graft for obstruction of superior vena cava caused by benign disease

Nine patients had operations for obstruction of the superior vena cava with superior vena caval syndrome caused by benign disease. Three patients had fibrosing mediastinitis, four had fibrosing mediastinitis with caseous necrosis, one had thrombosis of the superior vena cava around a pacemaker electrode, and one had spontaneous thrombosis of the superior vena cava. Patients ranged in age from 25 to 68 years. All bypass operations were performed with a composite spiral vein graft constructed from the patient's own saphenous vein, split longitudinally and wrapped around a stent in spiral fashion. The edges of the vein were sutured together to form a large conduit ranging in diameter from 9.5 to 15.0 mm. Six grafts were from the left innominate vein and three grafts were from the internal jugular vein. The grafts were placed into the right atrial appendage in all except one case, in which the graft was to the distal superior vena cava. Follow-up extends from 1 to 15 years. One patient required reoperation at 4 days for thrombosis at the innominate vein-graft anastomosis. Resection of the anastomosis and reconstruction of the graft rendered the patient symptom free. Two grafts closed during the first year after operation. One patient had advancing fibrosing mediastinitis, and a second bypass graft from the external jugular veins remain patent. Another patient had recurrence of spontaneous venous thrombosis. Thus seven of nine grafts remain patent for up to nearly 15 years and all but one patient is free of superior vena caval syndrome. These data show that bypass of the obstructed superior vena cava with a spiral vein graft relieves superior vena caval syndrome and demonstrate long-term patency of the graft.     

Superior vena cava graft for right liver and right lateral sector transplantation

BACKGROUND: The usefulness of cryopreserved superior vena cava (SVC) grafts for venous reconstruction remains to be evaluated in right liver and right lateral sector transplantation. METHODS: Reconstruction of the hepatic vein was performed when the congested area in the liver graft was significant. A vein graft with a suitable shape and length meeting the demands for the venoplasty was selected, and SVC grafts were used in 20 recipients. Surgical techniques were classified into five types according to the necessity of middle or short hepatic vein reconstruction in the liver graft. Surgical outcomes and vein graft patency were evaluated. RESULTS: All 20 recipients survived the operation without any complications caused by congestion. Liver functions were well recovered in the early postoperative period. The 1-year primary patency rates of cryopreserved vein grafts used for reconstructed right hepatic veins, inferior right hepatic veins, and middle hepatic vein tributaries were 100%, 94%, and 42%, respectively. CONCLUSIONS: SVC grafts were feasible for outflow tract reconstruction in right liver and right lateral sector transplantation, although the long-term patency of the grafts for middle hepatic vein reconstruction remains to be evaluated.     

Right liver adult-to-adult live donor liver transplantation in Hong Kong

The extension of live donor liver transplantation (LDLT) from children to adults went in parallel with the shift from using the left-liver graft to the right. Donor right hepatectomy, being a more major procedure, only intensifies the ethical controversy, which is central to LDLT. Since its debut in 1996, right-liver adult-to-adult LDLT has gone through a number of technical innovations and refinements based on constant review of outcomes and study of the relevant pathophysiology. To achieve unimpeded graft venous outflow, the middle hepatic vein was universally included and underwent venoplasty with the right hepatic vein before anastomosis with the recipient inferior vena cava. Donor safety was never compromised and was acquired by preservation of segment 4b hepatic vein in the remnant left lobe. Venovenous bypass, which was associated with adverse outcomes, is no longer used. Early restoration of the circulation through the inferior vena cava was made possible by release of the clamps to the latter before portal vein anastomosis. Through judicious use of the procedure, which was executed with a high degree of precision, using right-liver grafts more than 35% of the estimated liver mass, a 1-year recipient survival of more than 90% is achievable in our series.     

Hepatic venous outflow reconstruction in adult living donor liver transplants without portal hypertension

Graft congestion is one of the causes of poor graft function in segmental liver transplantation. Three factors are implicated in segmental graft congestion: graft size, hepatic venous outflow and portal inflow. The graft size must be matched to the body weight, which is conventionally done by using graft to body weight ratio. Hepatic blood outflow must be optimized by hepatic vein reconstruction, which can be complicated. High portal blood flow has been shown to be detrimental to small-for-size grafts. These factors are strictly connected to each other. They can all contribute to graft congestion and poor function, while one factor can compensate for the others and decrease congestion. Ideally, all the accessory veins should be reconstructed, if possible, to maximize the outflow. In the absence of portal hypertension and with an adequate sized graft, complex venous reconstruction may not be necessary. We present a case report of an adult living donor liver transplant with the favorable conditions of normal portal pressure and a large sized graft, but complicated by the presence of several accessory hepatic veins. A simple hepatic vein anastomosis was sufficient for adequate outflow and prompt graft function.