Minoru Umehara

Influence of cold ischemia time and graft transport distance on postoperative outcome in human liver transplantation.

Abstract.Purpose: The association between hepatic allograft cold ischemia time (CIT) and graft transport distance (GTD) in human liver transplantation was examined by investigating whether extended graft transportation prolongs the CIT and adversely affects graft survival.Methods: We retrospectively analyzed 186 consecutive orthotopic liver transplants (OLTs) done between May 1997 and July 1998. The number of miles from the donor hospital to the University of Pittsburgh Medical Center in a straight line was measured in each case, and defined as the GTD. The OLTs were divided into two groups according to whether the GTD was ≤200 miles or >200 miles. The latter group was then subdivided into groups of GTD 200–400 miles, GTD 400–600 miles, and GTD >600 miles. The CIT and graft outcome within 90 days after OLT were assessed.Results: Extended GTD prolonged the CIT (P < 0.001). The rate of hepatic allograft loss in the long GTD group was significantly higher than that in the short GTD group (P= 0.018). When the OLTs were subdivided according to GTD, the CIT increased and graft survival decreased as the GTD extended. Hepatic allograft transportation for a long distance prolonged the CIT and decreased the graft survival rate.Conclusion: Since prolonged CIT is a major risk factor, avoiding long-distance graft transportation is recommended when the donor risk factors are high.

Double-balloon enteroscopy for bilioenteric anastomotic stricture after pediatric living donor liver transplantation.

Bilioenteric anastomotic stricture after liver transplantation is still frequent and early detection and treatment is important. We established the management using double‐balloon enteroscopy (DBE) and evaluated the intractability for bilioenteric anastomotic stricture after pediatric living donor liver transplantation (LDLT). We underwent DBE at Jichi Medical University from May 2003 to July 2009 for 25 patients who developed bilioenteric anastomotic stricture after pediatric LDLT. The patients were divided into two types according to the degree of dilatation of the anastomotic sites before and after interventional radiology (IVR) using DBE. Type I is an anastomotic site macroscopically dilated to five times or more, and Type II is an anastomotic site dilated to less than five times. The rate of DBE reaching the bilioenteric anastomotic sites was 68.0% (17/25), and the success rate of IVR was 88.2% (15/17). There were three cases of Type I and 12 cases of Type II. Type II had a significantly longer cold ischemic time and higher recurrence rate than Type I (P = 0.005 and P = 0.006). In conclusion, DBE is a less invasive and safe treatment method that is capable of reaching the bilioenteric anastomotic site after pediatric LDLT and enables IVR to be performed on strictures, and its treatment outcomes are improving. Type II and long cold ischemic time are risk factors for intractable bilioenteric anastomotic stricture.

Living Donor Liver Transplantation for Neonates Using Segment 2 Monosubsegment Graft

The prognosis of liver transplantation for neonates with fulminant hepatic failure (FHF) continues to be extremely poor, especially in patients whose body weight is less than 3 kg. To address this problem, we have developed a safe living donor liver transplantation (LDLT) modality for neonates. We performed LDLTs with segment 2 monosubsegment (S2) grafts for three neonatal FHF. The recipient age and body weight at LDLT were 13–27 days, 2.59–2.84 kg, respectively. S2 or reduced S2 grafts (93–98 g) obtained from their fathers were implanted using temporary portacaval shunt. The recipient portal vein was reconstructed at a more distal site, such as the umbilical portion, to have the graft liver move freely during hepatic artery (HA) reconstruction. The recipient operation time and bleeding were 11 h 58 min–15 h 27 min and 200–395 mL, respectively. The graft‐to‐recipient weight ratio was 3.3–3.8% and primary abdominal wall closure was possible in all cases. Although hepatic artery thrombosis occurred in one case, all cases survived with normal growth. Emergency LDLT with S2 grafts weighing less than 100 g can save neonates with FHF whose body weight is less than 3 kg. This LDLT modality using S2 grafts could become a new option for neonates and very small infants requiring LT.

Living-Donor Liver Transplantation in 126 Patients with Biliary Atresia: Single-Center Experience

OBJECTIVES To describe our experience with 126 consecutive living-donor liver transplantation (LDLT) procedures performed because of biliary atresia and to evaluate the optimal timing of the operation. PATIENTS AND METHODS Between May 2001 and January 2010,126 patients with biliary atresia underwent 130 LDLT procedures. Mean (SD) patient age was 3.3 (4.2) years, and body weight was 13.8 (10.7) kg. Donors included 64 fathers, 63 mothers, and 3 other individuals. The left lateral segment was the most commonly used graft (75%). Patients were divided into 3 groups according to body weight: group 1, less than 8 kg (n = 40); group 2,8 to 20 kg (n = 63); and group 3, more than 20 kg (n = 23). Medical records were reviewed retrospectively. Follow up was 4.5 (2.7) years. RESULTS All group 3 donors underwent left lobectomy, and all group 1 donors underwent left lateral segmentectomy. No donors required a second operation or died. Comparison of the 3 groups demonstrated that recipient Pediatric End-Stage Liver Disease score in group 1 was highest, operative blood loss in group 2 was lowest (78 mL/kg), and operative time in group 3 was longest (1201 minutes). Hepatic artery complications occurred more frequently in group 1 (17.9%), and biliary stenosis (43.5%) and gastrointestinal perforation (8.7%) occurred more frequently in group 3. The overall patient survival rates at 1, 5, and 9 years was 98%, 97%, and 97%, respectively. Five-year patient survival rate in groups 1,2, and 3 were 92.5%, 100%, and 95.7%, respectively. Gastrointestinal perforation (n = 2) was the primary cause of death. CONCLUSIONS Living-donor liver transplantation is an effective treatment of biliary atresia, with good long-term outcome. It seems that the most suitable time to perform LDLT to treat biliary atresia is when the patient weighs 8 to 20 kg.

Living donor liver transplantation for ornithine transcarbamylase deficiency

Wakiya T, Sanada Y, Mizuta K, Umehara M, Urahasi T, Egami S, Hishikawa S, Fujiwara T, Sakuma Y, Hyodo M, Murayama K, Hakamada K, Yasuda Y, Kawarasaki H. Living donor liver transplantation for ornithine transcarbamylase deficiency.
Pediatr Transplantation 2011: 15: 390–395.

Hepatic venous outflow obstruction in living donor liver transplantation: balloon angioplasty or stent placement?

BACKGROUND The incidence of hepatic venous outflow obstruction (HVOO) has been reported to be 5%-13% when a partial graft is used for orthotopic liver transplantation (OLT). HVOO leads to graft congestion, portal hypertension, and finally cirrhosis, which jeopardizes both graft and recipient survivals. In this study, we sought to identify perioperative factors influencing HVOO and to investigate conditions that require stent placement. PATIENTS AND METHODS From February 1994 to December 2010, we performed 40 living donor liver transplantations (LDLT). HVOO occurred in 5 cases (12.5%), all of which were left lobe grafts. Because HVOO was not observed in patients with body weight (BW) <30 kg, we investigated the other 28 cases with BW >30 kg. RESULTS There was no difference from unaffected subjects except for cold ischemic time (CIT), which was significantly longer: 86.2 ± 10.4 minutes vs 46.0 ± 4.8 minutes (P = .001). Balloon angioplasty, which was selected as the initial treatment for all stricture patients, improved 2 patients after 1 and 5 treatments, respectively, but 3 subjects underwent repeated HVOO, finally being treated with self-expandable metallic stents at 9, 6, and 10 years after LDLT, respectively. All patients finally resolved their strictures. CONCLUSION HVOO reflects intimal hyperplasia and fibrosis at the anastomotic sites or compression and twisting of the anastomosis caused by graft regeneration. In addition, progression of chronic rejection and fibrosis are possibly responsible for late-onset HVOO. Longer CIT possibly reflects difficulties in the venoplasty before anastomosis. No bleeding or thrombosis complications were observed during dilatation among our cases. The selection of the stent size for each case and careful stent deployment are important to prevent complications. Stent placement should be considered in patients with chronic rejection who are refractory to several balloon angioplasties with early-onset or late-onset HVOO.

Torsion of an accessory lobe of the liver in a child: report of a case.

We report a case of torsion of an accessory lobe of the liver (ALL) in a 14-year-old girl. The patient was admitted for acute abdominal pain and laparotomy revealed an ALL, the pedicle of which was elongated with 180° torsion. The diagnosis was not made preoperatively because of the rarity of this condition. However, a close relationship between omphalocele repair and the development of ALL has been reported; thus, a history of omphalocele repair should alert the doctor to the possibility of this condition, which could be suggested by imaging findings preoperatively. Torsion of an ALL should be included in the differential diagnosis of a patient with a history of omphalocele, who presents with acute abdominal symptoms.

Endovascular interventions for hepatic artery complications immediately after pediatric liver transplantation

Hepatic artery complications after living donor liver transplantation (LDLT) can directly affect both graft and recipient outcomes. For this reason, early diagnosis and treatment are essential. In the past, relaparotomy was generally employed to treat them. Following recent advances in interventional radiology, favorable outcomes have been reported with endovascular treatment. However, there is ongoing discussion regarding the best and safe time for definitive endovascular interventions. We herein report a retrospective analysis for six children with early hepatic artery complication after pediatric LDLT who underwent endovascular treatment as primary therapy at our institution. We evaluate the usefulness of endovascular treatment for hepatic artery complication and its optimal timing. The mean patient age was 11.9 months and mean body weight at LDLT was 6.7 kg. The mean duration between the transplantation and first endovascular treatment was 5.3 days. Five of the six patients were technically successful treated by only endovascular treatment. Of these five patients, two developed biliary complications. Endovascular procedures were performed 10 times in six patients without any complications and nine of the 10 procedures were successful. By selecting optimal devices, our findings suggest that endovascular treatment can be feasible and safe in the earliest time period after pediatric LDLT.

Liver Transplantation for Wilson's Disease in Pediatric Patients: Decision Making and Timing

Transplantation for Wilsons disease occupies 1/3 of the cases for metabolic diseases in Japan. At the end of 2009, 109 transplantations had been performed including three deceased donor cases in the Japanese registry. We herein discuss problems of transplantation for Wilsons disease as well as its indication, timing, and social care. We retrospectively reviewed four fulminant cases and two chronic cases who underwent living donor liver transplantation. There were two boys and two girls. Four adolescents of average age 11.3 years underwent living donor liver transplantation. Duration from onset to transplantation ranged from 10 to 23 days. Average Model for End-stage Liver Disease (MELD) score was 27.8 (range=24-31). All patients were administrated chelates prior to transplantation. MELD, New Wilsons index, Japanese scoring for liver transplantation, and liver atrophy were useful tools for transplantation decision making; however, none of them was an independent decisive tool. Clinical courses after transplantation were almost uneventful. One girl, however, developed an acute rejection episode due to noncompliance at 3 years after transplantation. All patients currently survive without a graft loss. No disease recurrence had been noted even using living related donors. Two adults evaluated for liver transplantation were listed for deceased donor liver transplantation. Both candidates developed cirrhosis despite long-term medical treatment. There were no appropriate living donors for them. There are many problems in transplantation for Wilsons disease. The indications for liver transplantation should be considered individually using some decision-making tools. The safety of the living donor should be paid the most attention.

Plasma Exchange-based Plasma Recycling Dialysis System as an Artificial Liver Support

Abstract:  We developed a plasma recycling dialysis (PRD) system based on plasma exchange (PE). In this system, rapid reduction of toxic substances and restitution of deficient essential substances are performed by PE and subsequent blood purification is performed by dialysis between separated plasma recycled over a purification device and the patients blood across the membrane of a plasma separator. To demonstrate the safety and efficacy of this system, we used a pig model of fulminant hepatic failure (FHF) and anion exchange resin, activated charcoal and hemodialysis for the purification device. FHF was induced by intraportal administration of α‐amanitine (0.1 mg/kg) and lipopolysaccharides (1 µg/kg) in pigs. Three groups of animals were studied: group 1, diseased controls (N = 4); group 2, PE group (N = 4), 16 h after drug infusion the pigs underwent PE of approximately 1.2 L for 2 h; and group 3, PE + PRD group (N = 4), the pigs underwent PE followed by PRD for 6 h. The hemodynamic status of all animals was stable during the procedure. In group 3, the values of ammonia, total bile acid and total bilirubin continuously decreased and were significantly lower than those of the animals in group 2 24 h after the induction of FHF. The Fischer ratio was significantly higher than in group 2 after 24 h. Group 3 pigs maintained a higher level of consciousness and survived longer than group 2 pigs. Safety of this PE‐based PRD system was demonstrated and the removal of toxic substances was significant. This study confirmed the clinical utility of this system as an artificial liver support.