Use of arterial conduit as an alternative technique in arterial revascularization during orthotopic liver transplantation

BACKGROUND: The risk of hepatic artery thrombosis after orthotopic liver transplantation is higher in cases of poor hepatic arterial inflow, small or anomalous recipient hepatic arteries, unsafe native hepatic arteries. AIMS: To assess the use of arterial conduits as alternative technique for graft revascularization. PATIENTS: At the Liver Transplant Center of the "S. Giovanni Battista" Hospital in Torino, a review has been made of 600 consecutive orthotopic liver transplantations in 545 adult patients from 1990 to 1999. METHODS: In 95 orthotopic liver transplantations (15.8%) in 88 patients, the graft was supplied by infrarenal conduit, while in 505 orthotopic liver transplantations (84.2%) in 457 patients, a direct anastomosis was used. RESULTS AND CONCLUSIONS: The overall incidence of hepatic artery thrombosis in our series was 3.5% (21/600): 5.3% (5/91) for conduits and 3.2% (16/505) for standard technique (p=ns, chi2 test). The actuarial 5-year graft survival was 67.7% for conduits and 68.6% for the standard technique; p (log rank): ns. The iliac prosthesis torsion was the only complication related to the use of infrarenal iliac conduit. The arterial conduit, performed with donor iliac artery, is an effective and safe revascularization technique in patients at high risk of arterial thrombosis.     

Portal vein arterialization technique for liver transplantation patients

Liver transplantations were performed on two patients with hepatic failure caused by liver cirrhosis. Hard obsolete thrombi and portal venous sclerosis were observed in the major portal veins of both patients. The arteria colica media of one recipient and the portal vein of the donor were anastomosed end-to-end. The hepatic artery of the first donor was anastomosed end-to end with the gastroduodenal artery of the first recipient; meanwhile, the portal vein of the second donor was simultaneously anastomosed end- to-end with the common hepatic artery of the second recipient. The blood flow of the portal vein, the perfusion of the donor liver and liver function were satisfactory after surgery. Portal vein arterialization might be an effective treatment for patients whose portal vein reconstruction was difficult.     

Incidence and treatment of hepatic artery complications after orthotopic liver transplantation

AIM: To investigate the incidence and treatment of hepatic artery complications after orthotopic liver transplantation. METHODS: From February 1999 to May 2002, orthotopic liver transplantations (OLT) were performed in 72 patients with end-stage liver diseases with an average age of 40.2±13.6 years (ranged from 11 to 68 years), 56 were males and 16 females. The preoperative evaluation for the 72 patients was performed using duplexsonography, abdominal CT scan, and angiography of the hepatic artery. All donor grafts were perfused and preserved in University of Wisconsin solution at 4℃. OLT was performed with standard techniques with or without a veno-venous bypass. Reconstructions of hepatic artery were performed between the branch patches of gastroduodenal/hepatic or splenic/common hepatic artery confluence of the donors and recipients, and an end-to-end anastomosis between other arterial vessels of the donors and recipients was done. Arterial anastomosis was performed with interrupted 7-0/8-0 monofilament polypropylene suture under 3.5 x Ioupe magnification. Diagnosis of the complications of hepatic artery after OLT was based on the clinical presentations, ultrasound findings and arterial angiography. All patients were followed up regularly for duplex ultrasound scan after discharge. RESULTS: The overall incidence of arterial complications in 72 patients after OLTs was 1.4% (1/72). One 3cm pseudoaneurysm at the side of anastomotic site of hepatic artery was found by urgent arteriogram due to hemoperitoneum secondary to bile leakage after OLT. Subsequently the pseudoaneurysm was successfully embolized and the blood flow toward the donor liver in hepatic artery remained. The overall postoperative 30day mortality rate was 8.33%. The one-year survival rate was 83.72% in 50 patients with benign diseases and was 71.43% in 22 patients with malignant diseases following OLT. No death associated with complications of hepatic artery occurred. CONCLUSION: Careful preoperative evaluations and intraoperative microsurgical technique for hepatic artery reconstructions are the keys in prevention of hepatic artery complications after OLT.     

Graft survival following three occurrences of hepatic arterial thrombosis after living-related liver transplantation. A case report

Hepatic arterial thrombosis is a major cause of morbidity and graft loss in patients undergoing liver transplantation. We report the case of a patient who underwent living-related liver transplantation and suffered three instances of early hepatic arterial thrombosis requiring revascularization in the first 8 days after grafting. The patient was discharged with good graft function. A 21-month-old female with biliary atresia underwent living-related liver transplantation using her mother's extra-lateral segment. The donor middle hepatic artery was anastomosed end-to-end to the posterior branch of the donor's hepatic artery. The time of operation was 8 hr 36 min, and the blood loss was 193 mL. On postoperative day 5, the patient was returned to surgery to close a perforation in the transverse colon. At operation we found hepatic arterial thrombosis and performed a thrombectomy and redid the arterial anastomosis. Hepatic arterial thrombosis recurred during the operation, so we interposed the recipient's right radial artery between the graft artery and recipient posterior branch. On postoperative day 8, ultrasound showed a fluid collection in Winslow's pouch. After removing the fibrin clot, we discovered that hepatic arterial thrombosis had recurred in the interposed artery. We revascularized the graft using the right gastroepiploic artery. Arterial blood flow was restored, and graft function remained excellent.     

8a Liver transplantation: newer surgical approaches

The standard procedure for orthotopic liver transplantation remains transplantation of the whole organ together with resection of the vena cava and the use of venovenous bypass. In cases of severe mismatch of the donor and recipient vena cava, the piggyback technique, if necessary with vena cava plasty, is preferable. Furthermore, in all cases where venovenous bypass cannot be performed, the piggyback or other technique preserving the vena cava should be performed. In paediatric patients, reduced/size liver transplantation may be indicated because of the shortage of small livers. In the hands of experienced surgeons, the results of reduced-size liver transplantation in paediatric patients are similar to those of whole organ transplantation. Further innovative procedures to overcome the problem of organ shortage include split-liver and living related transplantation in children. Distinct advantages of living related transplantation can be seen in a well-functioning graft, lack of preservation injury, elective operation and optimal graft-size matching. The immunological advantage that has been claimed could not be demonstrated so far, and will need to be examined in the long-term follow-up. However, there remains a distinct disadvantage for living related transplantation with regard to the surgical technique. Pre-operative portal venous thrombosis should be carefully assessed, but is not a contraindication to liver transplantation if the confluence of the superior mesenteric vein and splenic vein is patent. Arterial reconstruction at the confluence of two arteries (hepatic and gastroduodenal or splenic artery) seems to be preferable to an end-to-end anastomosis because of improved inflow into the graft and a reduced risk of arterial stenosis and thrombosis. Where the common hepatic arteries are small, with reduced or reversed flow, and in patients with coeliac trunk stenosis, we recommend a direct approach to the suprarenal or infrarenal aorta. Bile duct anastomosis may preferably be performed with a side-to-side technique, to reduce early and late biliary complications.     

Hepatic artery reconstruction in pediatric liver transplantation: Experience from a single group

BackgroundThe reconstruction of hepatic artery is a challenging part of the pediatric liver transplantation procedure. Hepatic artery thrombosis (HAT) and stenosis are complications which may result in ischemic biliary injury, causing early graft lost and even death.MethodsTwo hundred and fifty-nine patients underwent liver transplantation in 2017 in a single liver transplantation group. Among them, 225 patients were living donor liver transplantation (LDLT) and 34 deceased donor liver transplantation (DDLT).ResultsIn LDLT all reconstructions of hepatic artery were microsurgical, while in DDLT either microsurgical reconstruction or traditional continuous suture technique was done depending on different conditions. There were five (1.9%) HATs: four (4/34, 11.8%) in DDLT (all whole liver grafts) and one (1/225, 0.4%) in LDLT (P = 0.001). Four HATs were managed conservatively using anticoagulation, and 1 accepted salvage surgery with re-anastomosis. Until now, 3 HAT patients remain in good condition, whereas two developed biliary complications. One of them needed to be re-transplanted, and the other patient died due to biliary complications.ConclusionsMicrosurgical technique significantly improves the reconstruction of hepatic artery in pediatric liver transplantation. The risk for arterial complications is higher in DDLT. Conservative therapy can achieve good outcome in selected HAT cases.     

Anatomical keys and pitfalls in living donor liver transplantation

The surgery of living donor liver transplantation is more technically challenging than cadaveric whole liver transplantation and liver resection for the treatment of various pathological conditions. It requires a thorough understanding of the intra- and extra-hepatic anatomical relationships between the portal vein, hepatic artery, biliary tract, and hepatic vein, and also their respective contributions to liver physiology. Although a precise understanding of general anatomical principles is the key to correctly performing living donor liver transplantation procedures, anatomic anomalies are often present, and the means of detecting them and the surgical methods of coping with them represent technical challenges. In this monograph, we describe the anatomical keys and pitfalls of living donor liver transplantation surgery based on our own experience with more than 1800 hepatectomies, and 150 living donor liver transplantations. We also elaborate on techniques of selective intermittent vascular occlusion and their teleological and practical background.     

Present status and prospects of living-related liver transplantation

Living-related liver transplantation (LRLT) is a relatively new surgical modality that has developed, in part, to overcome the shortage of available cadaveric livers for transplantation and as a method to provide liver graft implants from living donors for patients end-stage with liver disease in areas where the use of cadaveric livers is not yet practiced or permitted. Since 1988 almost 500 LRLTs have been performed globally. The safety of donors who provide a portion of their liver for grafting is of utmost concern, and only one donor death from this procedure has been reported in the literature. Postoperative survival in recipients depends on their pretransplant physical status, but emergency patients in rapid need of a liver have a poorer survival than elective LRLT patients for whom survival is about 80%. Children and infants are the main recipients of LRLTs, but adult patients particularly in Japan, are increasing in number, and present indications for LRLT surgery include not only cholestatic end-stage liver diseases but also metabolic disorders affecting the liver and emergency LRLTs for fulminant hepatic failure. Many ethical problems relating to the concept of liver transplantation, donor liver source, recipient selection, and reimplantation have yet to be resolved. But we believe that LRLTs and cadaveric liver transplantations are saving lives and that the practice should be continued.     

CEUS： A new imaging approach for postoperative vascular complications after right-lobe LDLT

AIM： To investigate contrast-enhanced ultrasound （CEUS） for early diagnosis of postoperative vascular complications after right-lobe living donor liver transplantation （RLDLT）. METHODS： The ultrasonography results of 172 patients who underwent RLDLT in West China Hospital, Sichuan University from January 2005 to June 2008 were analyzed retrospectively. Among these 172 patients, 16 patients＇ hepatic artery flow and two patients＇ portal vein flow was not observed by Doppler ultrasound, and 10 patients＇ bridging vein flow was not shown by Doppler ultrasound and there was a regional inhomogeneous echo in the liver parenchyma upon 2D ultrasound. Thus, CEUS examination was performed in these 28 patients. RESULTS： Among the 16 patients without hepatic artery flow at Doppler ultrasound, CEUS showed nine cases of slender hepatic artery, six of hepatic arterial thrombosis that was confirmed by digital subtraction angiography and/or surgery, and one of hepatic arterial occlusion with formation of lateral branches. Among the two patients without portal vein flow at Doppler ultrasound, CEUS showed one case of hematoma compression and one of portal vein thrombosis,and both were confirmed by surgery. Among the 10 patients without bridging vein flow and with liver parenchyma inhomogeneous echo, CEUS showed regionally poor perfusion in the inhomogeneous area, two of which were confirmed by enhanced computed tomography （CT）, but no more additional information about bridging vein flow was provided by enhanced CT. CONCLUSION： CEUS may be a new approach for early diagnosis of postoperative vascular complications after RLDLT, and it can be performed at the bedside.     

Living donor liver transplantation.

Initially living donor liver transplantation (LDLT) was almost exclusively performed in infants and children. Adult LDLT programmes were initiated several years later. In the west this programme was introduced in view of a critical shortage of deceased donors and a constant increase in waiting list mortality. At present, this procedure is accepted as a therapeutic option for patients with end-stage liver disease to make up for the shortage of donor organs from dead patients. In Asia, however, LDLT has become the predominant means of liver transplantation as donor organs from the diseased cannot be used for religious and ethical reasons. Although there have been significant improvements in surgical techniques and consequently in recipient outcome over recent years, the LDLT procedure is still associated with donor morbidity and even mortality. The overall reported donor mortality was 0.2% and donor morbidity ranged between 0% and 100%. Biliary complications and infections were the most commonly reported donor complications. Therefore, a thorough medical as well as psychological evaluation of the donor and recipient are necessary prior to this procedure. To date, LDLT comprises less than 5% of adult liver transplantations in Europe and in the United States. Recipient and graft survival are almost identical to those seen with liver transplantations from deceased donors (DD). Biliary and vascular complications are more often seen in the LDLT setting. So far, no studies have focussed on the impact of LDLT on waiting list mortality. There is international consensus that this procedure should be restricted to centres with large experience in deceased donor liver transplantations as well as in hepatobiliary surgery. Ethical issues, optimal utility and application of adult LDLT and optimal recipient and donor characteristics have yet to be defined.     

Complete recovery from fulminant hepatic failure with severe coma by living donor liver transplantation

In Japan, living donor liver transplantation has been established as a therapeutic strategy for the rescue of terminal liver disease, including fulminant hepatic failure that shows no signs of recovery. We performed living donor liver transplantation for a subacute type fulminant hepatic failure patient, who had developed a hepatic coma of grade V (no right reflex, no response to pain stimuli). The electroencephalogram indicated almost flat waves. However, cranial computed tomography revealed that brain edema was not severe in this case. The recipient did not have hepatitis virus and had not taken medication that had been determined to cause hepatitis. The recipient was a 12-year-old boy, 165.5 cm in height and 45.5 kg in weight. The donor was his mother, who was 42 years old; her blood type, type B, was identical to that of the boy. The mother's right hepatic lobe was transplanted to her son (the recipient). The post-transplantation condition of recipient was quite excellent. He recovered consciousness 3 days after liver transplantation, and rapidly attained normal hepatic function. The donor was discharged on the 20th postoperative day without any problems. The recipient was discharged on the 79th postoperative day without any neurological deficits. This case suggests that deep coma without electroencephalogram waves may not be a contraindication for living donor liver transplantation in fulminant hepatic failure patients, if the brain edema is not severe.     

Implantable Doppler probe for continuous monitoring of blood flow after liver transplantation

BACKGROUND/AIMS: Hepatic artery and portal vein thromboses after liver transplantation remain significant causes of graft loss. Doppler ultrasonography is useful for detecting the thrombosis early. Doppler examination requires specialized equipment and training. However the results depend on the skill of the operator. METHODOLOGY: We developed a new Doppler probe that can be implanted in the abdominal cavity. The probe was used for 48 hours in 10 living donor liver transplantation patients. RESULTS: In all recipients, hepatic arterial and portal flows were monitored continuously. The medical staff could easily operate the ultrasonography system at the bedside. CONCLUSIONS: The technique was useful for detecting hepatic blood flow for 48 hours after liver transplantation.     

Adult to adult living-related liver transplantation. The Paul-Brousse Hospital preliminary experience

AIM: Liver-graft shortages justify the development of adult living-related liver transplantation. The preliminary experience with this technique at Paul-Brousse Hospital is reported. PATIENTS ET METHODES: From January to July 2000, 7 adult to adult living-related liver transplantations were performed. Donors were 5 females and 2 males aged 20 to 53 years old (median: 41). A right liver graft was harvested in all cases. Recipients were 5 males and 2 females aged from 17 to 58 years old (median: 50) transplanted for viral cirrhosis (4 cases including 2 with hepatocellular carcinoma), subfulminant hepatitis (1 case), hepatocellular carcinoma on a healthy liver (1 case), and epithelioid hemangioendothelioma (1 case). Follow-up ranged from 41 to 157 days (median: 117 days). RESULTS: One donor had a biliary fistula that healed spontaneously. One donor had asterixis for 24 hours. The 7 donors are alive at home without any late complications. One recipient was retransplanted for hepatic artery thrombosis and 2 recipients had a biliary fistula that healed spontaneously. The 7 recipients are alive at home with normal liver function. CONCLUSION: Our experience and other reports suggest that adult to adult living-related liver transplantation is feasible with rare mortality and low morbidity in donors. Results in recipients are comparable to those obtained with cadaveric grafts. For a given patient the possibility of living related donation might extend the indications for transplantation without penalizing patients waiting for a cadaveric graft.     

Problems in adult living donor liver transplantation using the right hepatic lobe

BACKGROUND: Adult living donor liver transplantation (LDLT) is now widely applied to patients, children or adults, and the graft extends from the left hepatic lobe to the right hepatic lobe. Harvesting the right hepatic lobe would mean putting the donor at high risk. The congestion of a graft may cause small-for-size syndrome. The safety of the donor and its evaluation, which are related to the outcome for the recipient,play an important role in LDLT. How to decrease the congestion of the graft is another challenge to transplant experts. DATA SOURCES: A literature search from MEDLINE about adult LDLT in recent years was made to analyze the safety of the living donor and the innovation of surgical techniques for preventing small-for-size syndrome. RESULTS: The top priority for adult LDLT is donor safety. Preoperative donor evaluation consists of three stages: phase 1 for general evaluation, phase 2 for laboratory tests, and phase 3 for radiological evaluation of graft volume and vessel anatomy. The potential pathogenic mechanisms of small-for-size syndrome seem to be related to persistent portal hypertension and portal overperfusion. Improved surgical techniques for decreasing portal hypertension and preventing congestion of a graft may reduce the incidence of small-for-size syndrome. The improved techniques include reconstruction of the tributaries of the middle hepatic vein, end-to-side portocaval shunting, ligation of the splenic artery, dual-graft transplantation, and modified reconstruction of hepatic veins. CONCLUSION: With the careful preoperative assessment and the safety of the living donor, as well as improved surgical techniques, adult LDLT using the right lobe is safe.     

Risk factors contributing to hepatic artery thrombosis following living-donor liver transplantation

Background/Purpose

This study was carried out to investigate the risk factors contributing to hepatic artery thrombosis in living-donor liver transplantation.

Methods

Two hundred and twenty-two recipients (113 adults and 109 children) of living-donor liver transplantation were the subjects of this study. The diagnosis of hepatic artery thrombosis was made by color-Doppler ultrasonography and/or hepatic angiography. Parameters for this study were: (1) donor sex, age, and body weight; (2) recipient sex, age, body weight, liver disease, preoperative prothrombin time, and type of arterial reconstruction; and (3) previous liver transplantation.

Results

Hepatic artery thrombosis occurred in 12 patients (5.4%) at 3 to 15 days posttransplant. Recipient female sex and metabolic disorder as the original disease were found to be significantly associated with hepatic artery thrombosis. The 5-year patient survival rate in recipients with hepatic artery thrombosis (58.3%) was significantly lower than that in recipients without this complication (84.4%).

Conclusions

Female sex and metabolic disease may be factors contributing to hepatic artery thrombosis after living-donor liver transplantation. More intensive anticoagulation therapy for this patient population might decrease the incidence of hepatic artery thrombosis and, thus, posttransplant recipient mortality.     

Technical dilemma in living-donor or split-liver transplant

In partial liver transplantation for adults criteria for the extent of reconstruction of middle hepatic vein tributaries have not been clarified. After hepatic venous and portal anastomoses in living-donor liver transplantation using left liver graft without middle hepatic vein, color Doppler ultrasonography was applied to check venous and portal blood flow. Color Doppler ultrasonography demonstrated absent hepatic venous flow and reversed portal venous flow in the congested area of the left paramedian sector which had been drained by the divided branch of the middle hepatic vein. The area was darkly discolored before arterial reperfusion and under clamping of the artery. Reconstruction of the venous branch was added after arterial anastomosis. Color Doppler ultrasonography revealed restored normal venous outflow and portal inflow after venous reconstruction. Postoperative course of the recipient was uneventful with rapid recovery of liver function. We propose that middle hepatic vein tributaries should be reconstructed if color Doppler ultrasonography demonstrates absent venous flow and reversed portal flow, and if the liver volume excluding the discolored area under occlusion of the hepatic artery is estimated to be insufficient for postoperative metabolic demand.     

Aortic conduit aneurysm and enteric fistula formation in a post–liver transplant patient: A potential causative role for cytomegalovirus?

Hepatic arterial aortic conduits can be used as an alternative means of revascularizing the donor liver when the native recipient hepatic artery (HA) cannot be used. Cytomegalovirus (CMV) is a common Herpesviridae infection in patients who have undergone solid organ transplants. It can be asymptomatic but may cause fever and invasive disease affecting any organ system. Here we describe the first case in the literature of an aortic conduit aneurysm and concurrent CMV viremia following liver transplantation. We speculate on a causative role for CMV in the development of the aneurysm.     

Outflow reconstruction with arterial patch in domino liver transplantation: a new technical option

Domino liver transplantation (LT), using livers from familial amyloidotic polyneuropathy (FAP) patients, is a well described technique useful to expand donor pool. One of the main difficulties of this type of LT arises from the necessity to share the vascular pedicles between the graft and the donor. The most important challenge resides in restoring a proper hepatic venous outflow in the FAP-liver recipient. This is specially challenging when using the piggy-back technique, because the hepatic stumps may be too short. To overcome this issue, surgeons explored several techniques using different types of venous grafts. We describe a new technical option by using an arterial graft from the deceased donor. By using both iliac arteries a long graft is created and sutured as needed to the hepatic vein stump. We describe herein this new technique employed in a domino liver recipient who underwent retransplantation for ischemic cholangitis. The procedure was performed using the piggy-back technique; the venous stump of the FAP liver was reconstructed with the arterial graft. The patient had uneventful postoperative and mid-term hepatic function, and anastomosis was patent 24 months after LT.     

Establishment of a new pig model for auxiliary partial orthotopic liver transplantation

AIM: To establish a new pig model for auxiliary partial orthotopic liver transplantation (APOLT). METHODS: The liver of the donor was removed from its body. The left lobe of the liver was resected in vivo and the right lobe was used as a graft. After the left lateral lobe of the recipient was resected, end-to-side anastomoses of suprahepatic inferior vena cava and portal vein were performed between the donor and recipient livers, respectively. End-to-end anastomoses were made between hepatic artery of graft and splenic artery of the host. Outside drainage was placed in donor common bile duct. RESULTS: Models of APOLT were established in 5 pigs with a success rate of 80%. Color ultrasound examination showed an increase of blood flow of graft on 5th d compared to the first day after operation. When animals were killed on the 5th d after operation, thrombosis of hepatic vein (HV) and portal vein (PV) were not found. Histopathological examination of liver samples revealed evidence of damage with mild steatosis and sporadic necrotic hepatocytes and focal hepatic lobules structure disorganized in graft. Infiltration of inflammatory cells was mild in portal or central vein area. Hematologic laboratory values and blood chemical findings revealed that compared with group A (before transplantation), mean arterial pressure (MAP), central venous pressure (CVP), buffer base (BB), standard bicarbonate (SB) and K+ in group B (after portal vein was clamped) decreased (P<0.01). After reperfusion of the graft, MAP, CVP and K+ restored gradually. CONCLUSION: Significant decrease of congestion in portal vein and shortened blocking time were obtained because of the application of in vitro veno-venous bypass during complete vascular clamping. This new procedure, with such advantages as simple vessel processing, quality anastomosis, less postoperative hemorrhage and higher success rate, effectively prevents ischemia reperfusion injury of the host liver and deserves to be spread.     

Management of early hepatic artery occlusion after liver transplantation with failed rescue

Hepatic artery thrombosis is a serious complication after liver transplantation which often results in biliary complications, early graft loss, and patient death. It is generally thought that early hepatic artery thrombosis without urgent re-vascularization or re-transplantation almost always leads to mortality, especially if the hepatic artery thrombosis occurs within a few days after transplantation. This series presents 3 cases of early hepatic artery thrombosis after living donor liver transplantation, in which surgical or endovascular attempts at arterial re-vascularization failed. Unexpectedly, these 3 patients survived with acceptable graft function after 32 mo, 11 mo, and 4 mo follow-up, respectively. The literatures on factors affecting this devastating complication were reviewed from an anatomical perspective. The collective evidence from survivors indicated that modified nonsurgical management after liver transplantation with failed revascularization may be sufficient to prevent mortality from early hepatic artery occlusion. Re-transplantation may be reserved for selected patients with unrecovered graft function.