Microsurgical Back Wall Support Suture Technique With Double Needle Sutures on Hepatic Artery Reconstruction in Living Donor Liver Transplantation

Validation of Novel Microsurgical Vessel Anastomosis Techniques: A Systematic Review

INTRODUCTION

 Thorough validation of novel microsurgical techniques is deemed essential before their integration into clinical practice. To achieve proper validation, the design of randomized controlled trials (RCTs) should be undertaken, accompanied by the execution of comprehensive statistical analyses, including confounder adjustment and power analysis. This systematic review aims to provide an encompassing overview of the validation methodologies employed in microsurgical studies, with a specific focus on innovative vessel anastomosis techniques.

METHODS

 A literature search was conducted in PubMed for articles describing the validation of novel microsurgical vessel anastomosis techniques in animal or human subjects.

RESULTS

 The literature search yielded 6,658 articles. A total of 6,564 articles were excluded based on title and abstract. Ninety-four articles were assessed for full-text eligibility. Forty-eight articles were included in this systematic review. Out of 30 comparative studies, 9 studies validated novel modified interrupted suture techniques, 6 studies modified continuous techniques, 6 studies modified sleeve anastomosis techniques, 1 study a modified vesselotomy technique, 7 studies sutureless techniques, and 1 study a modified lymphaticovenular anastomosis technique. Twenty-eight studies contained animals (n = 1,998). Fifteen animal studies were RCTs. Two studies contained human/cadaveric subjects (n = 29). Statistical power analysis and confounder adjustment were performed in one animal study. Out of 18 noncomparative studies, 5 studies validated novel modified interrupted suture techniques, 1 study a modified continuous technique, 2 studies modified sleeve anastomosis techniques, 4 studies modified vesselotomy techniques, 4 studies sutureless techniques, and 2 studies modified lymphaticovenular anastomosis techniques. Ten studies contained animal subjects (n = 320), with two RCTs. Eight studies contained human subjects (n = 173). Statistical power analysis and confounder adjustment were performed in none of the animal or human studies.

CONCLUSION

 The current methods of microsurgical technique validation should be reconsidered due to poor study design. Statistical analysis including confounder adjustment and power analysis should be performed as a standard method of novel technique validation.

Techniques of hepatic arterial reconstruction in liver transplantation

BACKGROUND

Hepatic artery reconstruction is an essential part of liver transplantation. This difficult stage of the operation is even more demanding in living donor liver transplantation than in deceased donor liver transplantation. One of the most important advances in hepatic artery reconstruction for living liver grafts was the introduction of microsurgical techniques involving an operative microscope or surgical loupe. Many surgical reconstruction techniques have been used in this field.

PURPOSE

In this article, first, we will talk about the hepatic artery reconstruction techniques that are frequently used in deceased donor liver transplantation, and afterward, we will talk about the hepatic artery reconstruction techniques used in living donor liver transplantation, which include the hepatic artery reconstruction technique we use and call "one stay corner suture technique".

CONCLUSIONS

We think high-volume transplant centers should tend to develop a standardized technique for doing hepatic artery reconstruction with their teams. We think the "one stay corner suture technique" can be easily applied in centers that perform LDLT.

A New Strategy of Liver Transplantation for Locally Advanced Unresectable Perihilar Cholangiocarcinoma Using Living Grafts With Simultaneous Resection of Recipients' Hepatic Artery and Portal Vein Without Neoadjuvant Radiation: A Case Report

BACKGROUND

Perihilar cholangiocarcinoma (pCCA) is often unresectable, because it includes crucial blood vessels in portal area. The prognosis of locally advanced unresectable cholangiocarcinomas is extremely poor. Recently, there have been several reports of the prognosis improving drastically with transplantation and combined chemoradiation therapy. However, liver transplantation for pCCA has 2 big problems. The first is that pCCA is located at a lethal position and its progress is sometimes rapid; therefore, the optimal timing of transplantation is sometimes lost. The second is vascular complications associated with neoadjuvant radiation, especially in living donor liver transplantation (LDLT). To overcome these problems, we performed conversion surgery using LDLT with simultaneous resection of the hepatic artery and portal vein, instead of neoadjuvant radiation. Herein, we report our experience of interposition reconstruction.

METHODS

A 31-year-old man with primary sclerosing cholangitis (PSC) was diagnosed with locally advanced unresectable pCCA. The patient underwent radical chemotherapy (gemcitabine/cisplatin/S-1) and avoided radiation because of PSC. After 6 months, positron emission tomography-computed tomography revealed no lymph node metastasis. There was no time to wait. We immediately performed LDLT with simultaneous resection of hepatic artery and portal vein, and microsurgical reconstruction using auto-vessel grafts.

RESULTS

The recipient recovered and was discharged 31 days posttransplant. His liver function improved, and he has had no recurrence after LDLT.

CONCLUSION

LDLT with neoadjuvant radiation is associated with high risk of vascular complications. In some cases, conversion surgery after radical chemotherapy using good timing LDLT without radiation may increase chances of transplantation for locally advanced pCCA.

The "W" Technique: A Safe and Reproducible Technique for Hepatic Artery Reconstruction in Living Donor Liver Transplantation

Background

Reconstruction of the hepatic arterial inflow can be technically demanding in living donor liver transplantation, and thrombosis can result in graft loss and mortality. We describe the safe and reproducible “W” technique to reconstruct the hepatic artery and outcomes before and after adoption of the technique in a consecutive series of liver transplants at 2 high-volume living donor liver transplant centers.

Material/Methods

Prospectively collected data were analyzed to compare the outcomes before and after introduction of a standardized “W” technique for reconstruction of the hepatic artery in 2 high-volume living donor liver transplant programs.

Results

In a consecutive series of 675 liver transplants, of which 27 were deceased donor transplants and 648 were living donor transplants, 443 transplants were performed with a standard interrupted reconstruction of the hepatic artery under loupes. These transplants were performed by a single surgeon, with an incidence of hepatic artery thrombosis of 2%. After introduction of the “W” technique, despite the arterial reconstruction being done by several surgeons in the early part of their learning curve, the incidence of hepatic artery thrombosis decreased to 0.86% in the next 232 transplants.

Conclusions

The “W” technique is a simple, easy to learn and teach technique for reconstruction of the hepatic artery without the use of the operating microscope in living donor liver transplantation.

Overcoming Hepatic Artery Thrombosis After Living Donor Liver Transplantations: An Experience from Asan Medical Center

Background

Hepatic artery (HA) reconstruction in living donor liver transplantation (LDLT) is more technically demanding than deceased donor LT (DDLT) because of the small diameter and short HA stump of the partial liver graft. Hence, hepatic artery thrombosis (HAT) can occur infrequently even though the HA is reconstructed microscopically. HAT is closely related to graft failure and mortality. Therefore, HAT should be detected early and HA flow reconstituted using several arterial inflows. We successfully performed redo HA reconstruction in LDLT and report our management process and outcomes.

Material/Methods

The right gastroepiploic artery (RGEA) was used in 15 patients, previous native HA in 3, and interposition graft from the aorta in 1. All HA reconstructions were performed under a microscope using the end-to-end interrupted suture method. We reviewed technical feasibility, cause of hepatic artery revision (HAR), patency of redo HA flow, graft salvage rate, time of revision, biliary complications, and mortality.

Results

Ten of 21 cases were salvage LT. Biliary complications developed in 6 cases. The mean interval of HAR with the RGEA was 1.5±1.2 postoperative days. All patients were alive without lethal complications of HAT during the mean follow-up period of 23.3 months. In the other 6 cases of HAR without using the RGEA, we performed redo HA reconstruction after thrombectomy with the native right HA (n=2), right gastric artery, left HA, gastroduodenal artery, and jump graft from the aorta (n=1, respectively). Among them, 3 died from biliary sepsis, graft dysfunction from large-sized ischemic injury, and pneumonia.

Conclusions

HAR with the RGEA is feasible for HAT management in LDLT patients without adequate hepatic arteries. When all inflows mentioned are unavailable, jump graft from the aorta using a cadaveric fresh iliac artery may be feasible.

What happened in 133 consecutive hepatic artery reconstruction in liver transplantation in 1 year?

Background

The immediate challenges during microvascular reconstruction of hepatic artery (HAR) during liver transplantation (LT) can be many. Hence, in order to give a cross sectional view of these problems this study over a period of 1 year, showing our routine practice, was taken up.

Methods

From January 2015 to December 2015, a total of 133 LTs were performed in Kaohsiung Chang Gung Memorial Hospital, Taiwan. All hepatic artery (HA) reconstructions were performed by a microvascular surgeon under an operating microscope.

Results

In the 133 patients, one artery was anastomosed in 123 (92.5%) patients, two in 9 (6.8%) patients and three in 1 (0.7%) of the patient. Eleven (8.3%) arteries were less than 2 mm in size (1-1.9 mm). There were intimal dissections (IDs) involving either the donor or the recipient arteries of mild to severe nature in 9 (6.8%) patients. Immediately following graft arterial anastomosis, either there was no flow or an intraoperative hepatic artery thrombosis (HAT) was found in nine (7.1%-8 LDLT, 4.8%-1 DDLT) patients. Immediate re-do anastomosis was done in all of these patients who did well in the follow-up. The overall post-operative success rate was 99.2%. One patient (0.8%) developed postoperative HAT due to infection during follow up and died due to sepsis.

Conclusions

Small vessels or HA injury are the frequently encountered problems by a micro vascular surgeon. The other problems could be ID, need to do multiple reconstructions, immediate HAT and ability to re-do the HAR immediately.

The extra-anatomical jump graft reconstruction of the right hepatic artery after resection of a biliary tract malignancy with a common hepatic artery aneurysm: a case report

Performing resection of a biliary tract malignancy with a hepatic artery aneurysm is very challenging. Resection of the extrahepatic bile duct and extra‐anatomical reconstruction can be successfully performed using free radial artery autografts from the aorta to the right hepatic artery. Hepatic artery thrombosis can be prevented with intimal preservation.

Arterial and biliary complications after living donor liver transplantation: a single-center retrospective study and literature review

AIM

The mortality of patients on the waiting list for deceased donor liver transplantation (DDLT) is high, especially in countries where donation rates are low. Thus, living donor liver transplantation (LDLT) is an attractive option. However, compared with DDLT, LDLT is associated with increased rates of arterial and biliary complications. We examined the rates of complications and risk factors following LDLT.

METHODS

We retrospectively investigated and compared the rates of complications of DDLT and LDLT in our institute. We also performed univariate and multivariate analyses to identify the independent risk factors for these complications. The complications and specific disadvantages of LDLT were reviewed and discussed.

RESULTS

The incidence rate of arterial complications in LDLT was 6.0%, compared with 3.2% (13/441) in DDLT. A multivariate analysis identified low body weight (P = 0.032) as the only independent risk factor for hepatic artery thrombosis. The rate of all biliary complications in LDLT was 17.3%, compared with 18.7% in DDLT. The risk factors for biliary stricture identified by the multivariate analysis were recurrent cholangitis and the number of bile ducts. The durations of hospital stay and overall survival rates were similar between the two groups.

CONCLUSION

Given the shortage of deceased donor organs, we believe that LDLT is acceptable in an attempt to meet demand.

Vascular complications in living donor liver transplantation at a high-volume center: Evolving protocols and trends observed over 10 years

Vascular complications continue to have a devastating effect on liver transplantation recipients, even though their nature, incidence, and outcome might have actually changed with increasing experience and proficiency in high-volume centers. The aim of this study was to analyze the trends observed in vascular complications with changing protocols in adult and pediatric living donor liver transplantation over 10 years in 2 time frames in terms of nature, incidence, and outcome. It is a retrospective analysis of 391 (group 1, January 2006 to December 2010) and 741 (group 2, January 2011 to October 2013) patients. With a minimum follow-up of 2 years, incidence of hepatic artery thrombosis (HAT) in adults has reduced significantly from 2.2% in group 1 to 0.5% in group 2 (P = 0.02). In group 2, nonsignificantly, more adult patients (75% with HAT) could be salvaged compared with only 25% patients in group 1 (P = 0.12). However, HAT in children had 100% mortality. Incidence of portal vein thrombosis (PVT) in complicated transplants in 2 eras remained the same (P = 0.2) and so has its mortality. The thrombosis rate of the neo-middle hepatic vein was significantly reduced in group 2 (P = 0.01). The incidence of HAT, particularly in adults, has decreased significantly though PVT has continued to puzzle surgeons in complicated transplants. In high-volume centers, increasing proficiency, technical modifications, early diagnosis, and multimodality of treatment is the key to decrease overall morbidity and mortality due to vascular complications. Liver Transplantation 23 457-464 2017 AASLD.

The effects of endothelial cells-preserving technique on microsurgical vascular reconstruction in biliary tract malignancy: report of twenty cases

We describe our experience of resectional surgery with microsurgical reconstruction of the hepatic arteries in 20 cases with biliary tract malignancy. Hepatic artery thrombosis (HAT) is a lethal complication; therefore, it is important to perform microsurgical reconstruction safely. Recently, we adopted the back wall support suture technique with double needle sutures that does not require the damaged short arteries to be turned over. In this technique, each stitch is placed from the inner side to the outer side to keep endothelial cells. The purpose of this study was to develop safety methods. From 2003 to 2012, 20 patients with biliary tract malignancy with possible involvement of the hepatic arteries underwent resectional surgery with microvascular reconstruction (cholangiocarcinoma: n = 15; others: n = 5). For this cohort study, patients were divided into two groups: group I (n = 5) included patients who underwent the conventional ‘twist technique’ and group II (n = 15) included patients who underwent the microsurgical back wall support suture technique with double needle sutures and received gabexate mesilate, a strong serine protease inhibitor (40 mg/kg/day) for 7 days. We investigated HAT using Doppler ultrasonography for 10 days. No postoperative mortality was observed. The incidence of HAT was only one case in group I, and there was no significant difference between the two groups. However, the value of the pulsatile index and acceleration time were significantly improved in group II. In conclusion, the back wall support suture technique with gabexate mesilate administration during microvascular reconstruction was found to be safe. It is important to keep endothelial cells healthy for microvascular reconstruction.

Partial portal arterialization for hepatic arterial thrombosis after living-donor liver transplant

OBJECTIVES

The most serious, life-threatening complication after living-donor liver transplant is a hepatic arterial thrombosis. Although possible therapies for acute hepatic arterial thrombosis include revascularization to salvage the graft, or retransplant, these may be difficult to perform owing to technical aspects and donor shortages. Previously, we reported the usefulness of partial portal arterialization in such cases.

MATERIALS AND METHODS

Four cases of partial portal arterialization for hepatic arterial occlusion after living-donor liver transplant were reviewed. The surgical procedure of partial portal arterializations involves making an arteriovenous shunt via a side-to-side anastomosis, using mesenteric vessels approximately 2 mm in diameter.

RESULTS

After partial portal arterialization, hepatic arterial flow was not detected, but graft injury owing to hypoxia gradually improved in all cases. In 1 case, occlusion of the arteriovenous shunt itself and the collateral artery to the graft were identified by angiography 45 days after partial portal arterialization. In another case, massive ascites, pleural effusion, and variceal changes of the mesenteric veins owing to portal hypertension were identified, and surgical closure of the shunt was performed 152 days after partial portal arterialization. In the other 2 cases, there were no definite problems related to partial portal arterialization, but the patients died owing to other complications.

CONCLUSIONS

When hepatic arterial thrombosis occurs after living-donor liver transplant, revascularization should be performed first. However, this sometimes may be difficult, as when the arterial dissection reaches into the graft. Partial portal arterialization is an easy and effective surgical procedure. Therefore, partial portal arterialization appears to be a useful option to gain time until collateral arterial vessels develop or retransplant, even if revascularization cannot be performed.

Right gastroepiploic artery is the first alternative inflow source for hepatic arterial reconstruction in living donor liver transplantation

BACKGROUND

Sufficient arterial flow after living donor liver transplantation (LDLT) is closely related to graft survival and prevention of postoperative complications. However, some unfavorable hepatic arterial conditions in recipients preclude reconstruction, requiring alternative stumps. We have used the right gastroepiploic artery (RGEA) as a first alternative for hepatic inflow.

METHODS

From January 2006 to December 2008, we performed 754 LDLTs including 28 cases of RGEA among hepatic arterial anastomoses. The arterial anastomosis was performed by an single surgeon under 859 a microscope using an end-to-end interrupted suture technique. RGEA was mobilized over 15 cm from the greater curvature of stomach and greater omentum.

RESULTS

The indications for RGEA use included severe hepatic arterial injury from previous transarterial chemoembolization (n=14), need for additional arterial flow in dual-grafts LDLT (n=13), poor blood flow from the recipient hepatic artery (n=3), and arterial injury during hilar dissection (n=3). The mean diameter of the isolated RGEA was 2.0±0.2 mm (range: 1.0-2.5). Most hepatic arterial anastomoses were performed with a significant size discrepancy of more than twofold. All reconstructed hepatic arterial flowes showed good; no complication was identified during the mean follow-up period of 56 months to date.

CONCLUSIONS

Using RGEA as an alternative arterial inflow is a simple, reliable procedure for situations of inadequate recipient hepatic or multiple graft arteries.

Endovascular management of early hepatic artery thrombosis after living donor liver transplantation

To study the feasibility of endovascular management of early hepatic artery thrombosis (HAT) after living-donor liver transplantation (LDLT) and to clarify its role as a less invasive alternative to open surgery. A retrospective review of 360 recipients who underwent LDLT. Early HAT developed in 13 cases (3.6%). Diagnosis was performed using Doppler, CT angiography, and digital subtraction angiography. Intra-arterial thrombolysis (IAT) was performed using streptokinase or tPA. In case of underlying stricture, PTA was attempted. If the artery did not recanalize, continuous infusion was performed and monitored using Doppler US. Initial surgical revascularization was successful in 2/13 cases. IAT was performed in 11/13 cases. The initial success rate was 81.8% (9/11), the failure rate was 18.2% (2/11). Rebound thrombosis developed in 33.3% (3/9). Hemorrhage developed after IAT in 2/11 cases (18.2%). Definite endovascular treatment of HAT was achieved in 6/11 cases (54.5%) and definite treatment (surgical, endovascular or combined) in 9/13 cases (69%). (Follow-up 4 months-4 years). Endovascular management of early HAT after LDLT is a feasible and reliable alternative to open surgery. It plays a role as a less invasive approach with definite endovascular treatment rate of 54.5%.

Microsurgical reconstruction of hepatic artery in A-A LDLT: 124 consecutive cases without HAT

AIM

To retrospectively investigate microsurgical hepatic artery (HA) reconstruction and management of hepatic thrombosis in adult-to-adult living donor liver transplantation (A-A LDLT).

METHODS

From January 2001 to September 2009, 182 recipients with end-stage liver disease underwent A-A LDLT. Ten of these patients received dual grafts. The 157 men and 25 women had an age range of 18 to 68 years (mean age, 42 years). Microsurgical techniques and running sutures with back-wall first techniques were performed in all arterial reconstructions under surgical loupes (3.5 x) by a group of vascular surgeons. Intimal dissections were resolved by interposition of the great saphenous vein (GSV) between the donor right hepatic artery (RHA) and recipient common HA (3 cases) or abdominal aorta (AA) (2 cases), by interposition of cryopreserved iliac vessels between the donor RHA and recipient AA (2 cases).

RESULTS

In the 58 incipient patients in this series, hepatic arterial thrombosis (HAT) was encountered in 4 patients, and was not observed in 124 consecutive cases (total 192 grafts, major incidence, 2.08%). All cases of HAT were suspected by routine color Doppler ultrasonographic examination and confirmed by contrast-enhanced ultrasound and hepatic angiography. Of these cases of HAT, two occurred on the 1st and 7th d, respectively, following A-A LDLT, and were immediately revascularized with GSV between the graft and recipient AA. HAT in one patient occurred on the 46th postoperative day with no symptoms, and the remaining case of HAT occurred on the 3rd d following A-A LDLT, and was cured by thrombolytic therapy combined with an anticoagulant but died of multiorgan failure on the 36th d after A-A LDLT. No deaths were related to HAT.

CONCLUSION

Applying microsurgical techniques and selecting an appropriate anastomotic artery for HA reconstruction are crucial in reducing the high risk of HAT during A-A LDLT.