Temporary auxiliary liver transplantation from a living donor to an adult recipient with familial amyloid polyneuropathy

International consensus recommendations for the RAPID procedure in liver transplantation: The RAPID Consensus ISLS 2023 Zurich Collaborative

INTRODUCTION

Since its beginning in 1963, liver transplantation has significantly advanced, now including transplant oncology. As indications broaden, donor supply reduces. The two-stage RAPID procedure (initially abbreviated as "Resection And Partial Liver Segment 2/3 Transplantation With Delayed Total Hepatectomy") has emerged to address the use of small-for-size grafts. However, a comprehensive evaluation of RAPID is essential given its novelty, scarcity, and diverse outcomes reported.

METHODS

The RAPID Consensus International Society of Liver Surgeons 2023 Zurich initiative established evidence around the RAPID procedure using the Danish Model of Consensus. Engaging an international community of specialists, the initiative ensured multidisciplinary involvement and used the GRADE framework to evaluate the quality of evidence and grade the recommendations.

RESULTS

Comprehensive discussions and debates led to internationally recognized recommendations addressing perioperative measures for RAPID. Key recommendations highlighted the significance of standardized nomenclature, specific indications, graft criteria, surgical techniques, optimal interstage timings, and measures to manage potential complications.

CONCLUSION

The consensus provides recommendations for the RAPID procedure, emphasizing transparency and outcome reporting. Establishing dedicated registries can improve care standards, which may ensure the benefits of RAPID by maximizing patient safety and improving outcomes.

Small-for-size syndrome in liver transplantation: Definition, pathophysiology and management

BACKGROUND

Since the first success in an adult patient, living donor liver transplantation (LDLT) has become an universally used procedure. Small-for-size syndrome (SFSS) is a well-known complication after partial LT, especially in cases of adult-to-adult LDLT. The definition of SFSS slightly varies among transplant physicians. The use of a partial liver graft has risks of SFSS development. Persistent portal vein (PV) hypertension and PV hyper-perfusion after LT were identified as the main factors. Hence, various approaches were explored to modulate PV flow and decrease PV pressure in order to alleviate this syndrome. Herein, the definition, clinical symptoms, pathophysiology, basic research, as well as preventive and treatment strategies for SFSS are reviewed based on an extensive review of the literature and on our own experiences.

DATA SOURCES

The articles were collected through PubMed using search terms "liver transplantation", "living donor liver transplantation", "living liver donation", "partial graft", "small-for-size graft", "small-for-size syndrome", "graft volume", "remnant liver", "standard liver volume", "graft to recipient body weight ratio", "sarcopenia", "porcine", "swine", and "rat". English publications published before March 31, 2020 were included in this review.

RESULTS

Many transplant surgeons performed PV flow modulation, including portocaval shunt, splenic artery ligation and splenectomy. With these techniques, patient outcome has been improved even when using a "small" graft. Other factors, such as preoperative recipients' nutritional and skeletal muscle status, graft congestion, and donor factors, were also identified as risk factors which all have been addressed using various strategies.

CONCLUSIONS

The surgical approach controlling PV flow and pressure could help to prevent SFSS especially in severely ill recipients. In the absence of efficacious medications to resolve SFSS, conservative treatments, including aggressive fluid balance correction for massive ascites, anti-microbiological therapy to prevent or control sepsis and intensive nutritional therapy, are all required if SFSS could not be prevented.

Temporary auxiliary partial orthotopic liver transplantation using a small graft for familial amyloid polyneuropathy

Donor shortage is a major issue in liver transplantation. We have successfully performed temporary auxiliary partial orthotopic liver transplantation (APOLT) using a small volume graft procured from a living donor for recipients with familial amyloid polyneuropathy (FAP). The aim of this study was to evaluate this procedure by comparing it with standard living donor liver transplantation (LDLT). We compared 13 recipients undergoing this procedure with 23 recipients undergoing a standard LDLT for the treatment of FAP. The estimated donor graft volume and the graft volume/recipient's standard liver volume ratio were significantly smaller in the temporary APOLT group than in the standard LDLT group. Postoperative complications were comparable, although the hospital stay was longer in the temporary APOLT group. All the patients safely underwent a remnant native liver resection about 2 months after their first operation in the temporary APOLT group. No symptoms related to FAP developed before the remnant liver resection, and no significant differences in graft and patient survival were observed between the two groups. We successfully performed temporary APOLT using a small volume liver graft without postoperative liver failure for FAP. Temporary APOLT for FAP might be a useful alternative procedure for expanding the donor pool for LDLT.

A new procedure for temporary auxiliary partial liver transplantation using living donor graft for patients with familial amyloid polyneuropathy

To introduce duct-to-duct biliary anastomosis to conventional temporary auxiliary partial orthotopic liver transplantation (APOLT) using living donor graft for patients with familial amyloid polyneuropathy, we modified the conventional APOLT procedure in a manner characterized by the use of the recipient's common hepatic duct for biliary reconstruction and the preservation of the right posterior section alone for the certain placement of a tube into the corresponding biliary tree for external biliary drainage (modified APOLT). This procedure was performed in 3 patients without biliary complications. No complications associated with the external drainage tube occurred. Here we report the techniques and results for this new procedure.

Administration of dalteparin based on the activated clotting time for prophylaxis of hepatic vessel thrombosis in living donor liver transplantation

Beginning in 2004, dalteparin doses based on activated clotting time (ACT) were administered for hepatic vessel thrombosis prophylaxis in living donor liver transplantation (LDLT). We verified the feasibility of this new therapy by comparing it with the previous one. From 1993 through 2008, 42 metabolic liver patients who underwent LDLT were divided into two groups. Group A (1993-2003, n = 32) was administered a fixed dalteparin dose and a large amount of fresh frozen plasma (FFP); Group B (2004-2008, n = 10) was administered an appropriate dosage of dalteparin to maintain the ACT levels from 140 to 150 seconds and a small amount of FFP. Group B was administered a lesser amount of FFP and more dalteparin. This resulted in longer activated partial thromboplastin time, lower fibrinogen degradation products D-dimer, and lower aspartate aminotransferase levels compared to group A; all differences were significant. Group B showed neither thrombotic nor hemorrhagic complications. Anticoagulation therapy comprising adjustment of the dalteparin dose based on ACT reduces thrombotic complications without increasing hemorrhagic complications. ACT measurement is a simple, reliable method for bedside monitoring of dalteparin anticoagulant effects for LDLT.

Strategies for improving the outcomes of small-for-size grafts in adult-to-adult living-donor liver transplantation

Living-donor liver transplantation (LDLT) has been refined and accepted as a valuable treatment for patients with end-stage liver disease in order to overcome the shortage of organs and mortality on the waiting list. However, graft size problems, especially small-for-size (SFS) grafts, remain the greatest limiting factor for the expansion of LDLT, especially in adult-to-adult transplantation. Various attempts have been made to overcome the problems regarding SFS grafts, such as increasing the graft liver volume and/or controlling excessive portal inflow to a small graft, with considerable positive outcomes. Recent innovations in basic studies have also contributed to the treatment of SFS syndrome. Herein, we review the literature and assess our current knowledge of the pathogenesis and treatment strategies for the use of SFS grafts in adult-to-adult LDLT.

Living Donor Liver Transplantation for Noncirrhotic Inheritable Metabolic Liver Diseases: Impact of the Use of Heterozygous Donors

BACKGROUND

In living donor liver transplantation (LDLT), the liver donor is almost always a blood relative; therefore, the donor is sometimes a heterozygous carrier of inheritable diseases. The use of such carriers as donors has not been validated. The aim of the present study was to evaluate the outcome of LDLT for noncirrhotic inheritable metabolic liver disease (NCIMLD) to clarify the effects of using a heterozygous carrier as a donor.

METHODS

Between June 1990 and December 2003, 21 patients with NCIMLD underwent LDLT at our institution. The indications for LDLT included type II citrullinemia (n = 7), ornithine transcarbamylase deficiency (n = 6), propionic acidemia (n = 3), Crigler-Najjar syndrome type I (n = 2), methylmalonic acidemia (n = 2), and familial amyloid polyneuropathy (n = 1). Of these 21 recipients, six underwent auxiliary partial orthotopic liver transplantation.

RESULTS

The cumulative survival rate of the recipients was 85.7% at both 1 and 5 years after operation. All surviving recipients are currently doing well without sequelae of the original diseases, including neurological impairments or physical growth retardation. Twelve of the 21 donors were considered to be heterozygous carriers based on the modes of inheritance of the recipients' diseases and preoperative donor medical examinations. All donors were uneventfully discharged from the hospital and have been doing well since discharge. No mortality or morbidity related to the use of heterozygous donors was observed in donors or recipients.

CONCLUSIONS

Our results suggest that the use of heterozygous donors in LDLT for NCIMLD has no negative impact on either donors or recipients, although some issues remain unsolved and should be evaluated in further studies.

Liver Transplantation for Familial Amyloid Polyneuropathy Non-VAL30MET Variants: Are Cardiac Complications Influenced by Prophylactic Pacing and Immunosuppressive Weaning?

BACKGROUND

Cardiac complications represent a cause of morbidity and mortality after liver transplantation among patients with familial amyloid polyneuropathy (FAP), especially for the non-VAL30MET variant types.

METHODS

We retrospectively evaluated 11 recipients from a nonendemic area including 90.9% affected by FAP variants. Preoperative cardiovascular symptoms were present in 81% of patients. An intraoperative pacemaker was placed prophylactically in 90.9% of all recipients. Since tacrolimus has been reported in the international literature to display cardiac toxicity, we evaluated the influence of intraoperative prophylactic pacing and rapid postoperative weaning from tacrolimus, mainly allowed by thymoglobulin on the occurrence of posttransplantation cardiac complications.

RESULTS

One patient received a combined heart-liver transplant, another, living donor liver transplantation. We did not observe any significant intraoperative cardiac complications. Postoperatively, the pacemaker was removed from all patients but 1. Five patients received tacrolimus and steroids; a subsequent, second group of 6 patients (54.5%) was treated with thymoglobulin followed by tacrolimus. At discharge the mean tacrolimus level was 10.6 ng/mL, whereas after 1 month it was 7.5 ng/mL. We observed a case of acute cellular rejection before discharge, which was successfully treated with intravenous steroids and OKT3. After a mean follow-up of 17.4 months (range, 1-31), 2 patients had died (18.1%): 1 due to sepsis and another, to MI. Two recipients experienced cardiac complications (18.1%), namely, the patient who died due to an myocardial infarction and a second one with a tachyarrhythmia, which was treated successfully with beta-blockers and amiodarone.

CONCLUSION

Prophylactic pacing and rapid weaning from immunosuppression are still associated with a significant rate of postoperative cardiac complications.

Feasibility of auxiliary partial orthotopic liver transplantation from living donors for patients with adult-onset type II citrullinemia

More than 20 patients with adult-onset type II citrullinemia have undergone liver transplantation, showing dramatic therapeutic effects. In Japan, living donor liver transplantation is the standard technique of liver transplantation because of the rare availability of cadaveric donors. The feasibility of auxiliary partial orthotopic liver transplantation (APOLT) for adult-onset type II citrullinemia to overcome the problem of a small-for-size graft in living donor liver transplantation has not been defined. We recently performed APOLT for patients with type II citrullinemia. Here, we present 2 patients: patient 1 was a 32-year-old man and patient 2 was a 43-year-old woman. Both patients suffered from hepatic encephalopathy, and laboratory data showed highly elevated plasma levels of ammonia and citrulline. In patient 1, the liver graft was obtained from a patient with familial amyloid polyneuropathy as a domino liver transplant. In patient 2, APOLT was performed after graft donation from her husband. The postoperative clinical courses of both patients were uneventful, and the neurological symptoms were completely resolved. The plasma concentrations of ammonia and citrulline normalized rapidly in both patients. APOLT can provide an adequate hepatocyte mass to correct the underlying enzyme deficiency in adult patients with type II citrullinemia. In addition, APOLT can be carried out safely to overcome the limitation of graft volume in living donor liver transplantation.

Living donor liver transplantation: issues regarding left liver grafts

BACKGROUND

The necessity of widening the indications for living donor liver transplantation (LDLT) has been emphasised. Clarification of the advantages and limitations of using a left liver graft for LDLT in adults is essential for donor safety.

METHODS

Between June 1990 and November 2002, 185 patients underwent LDLT at Shinshu University Hospital, Japan. In 97 of these, the graft comprised the left liver with or without the left portion of the caudate lobe. The peri-hepatectomy profiles of the donors, significance of left liver grafts, postoperative courses of the donors and recipients, and survival of the recipients were investigated.

RESULTS

All the donors recovered well and returned to a normal lifestyle. None required banked-blood transfusion or repeat surgery, and postoperative liver function tests had satisfactory results. The cold ischaemic time for the graft was 127+/-54 minutes. The graft volumes (GVs) ranged from 230 to 625 ml, and GV/standard liver volume (SV) ratios varied from 22% to 65%, at the time of transplantation. Although 85% of the liver grafts had GV/SV ratios <50%, no patient developed immediate postoperative liver failure. Patient survival rates were 89%, 84% and 84% at 1, 3 and 5 years, respectively.

DISCUSSION

Although LDLT using a left liver graft imposes potential postoperative complications (a small liver is more vulnerable to injury, and recipients of small grafts are at higher risk of complications during recovery), such grafts have yielded acceptable results in adult LDLT, with minimal burden to the donors.

Small-for-size graft problems in adult-to-adult living-donor liver transplantation

The number of adult patients undergoing living donor liver transplantation (LDLT) has recently increased. According to a recent Japanese survey, the 5-year survival rate in adults after surgery is only 69.7%, which is significantly poorer than that in pediatric series. Small-for-size grafts remain a problem in adult LDLT. The most commonly used liver graft for adult patients has shifted from the left liver to the right, which alleviates the problem of size disproportion. Right hepatectomy, however, increases the extent of the donor operation and raises an important ethical issue in LDLT. Patients who truly need a right liver graft should be carefully selected using evidence-based criteria.