Survival following right lobe split graft, living- and deceased-donor liver transplantation in adult patients: a systematic review and network meta-analysis

Comparing High- and Low-Model for End-Stage Liver Disease Living-Donor Liver Transplantation to Determine Clinical Efficacy: A Systematic Review and Meta-Analysis (CHALICE Study)

INTRODUCTION

Various studies have demonstrated that low-Model for End-Stage Liver Disease (MELD) living-donor liver transplant (LDLT) recipients have better outcomes with improved patient survival than deceased-donor liver transplantation (DDLT) recipients. LDLT recipients gain the most from being transplanted at MELD <25-30; however, some existing data have outlined that LDLT may provide equivalent outcomes in high-MELD and low-MELD patients, although the term "high" MELD is arbitrarily defined in the literature and various cut-off scores are outlined between 20 and 30, although most commonly, the dividing threshold is 25. The aim of this meta-analysis was to compare LDLT in high-MELD with that in low-MELD recipients to determine patient survival and graft survival, as well as perioperative and postoperative complications.

METHODS

Following PROSPERO registration CRD-42021261501, a systematic database search was conducted for the published literature between 1990 and 2021 and yielded a total of 10 studies with 2183 LT recipients; 490 were HM-LDLT recipients and 1693 were LM-LDLT recipients.

RESULTS

Both groups had comparable mortality at 1, 3 and 5 years post-transplant (5-year HR 1.19; 95% CI 0.79-1.79; p-value 0.40) and graft survival (HR 1.08; 95% CI 0.72, 1.63; p-value 0.71). No differences were observed in the rates of major morbidity, hepatic artery thrombosis, biliary complications, intra-abdominal bleeding, wound infection and rejection; however, the HM-LDLT group had higher risk for pulmonary infection, abdominal fluid collection and prolonged ICU stay.

CONCLUSIONS

The high-MELD LDLT group had similar patient and graft survival and morbidities to the low-MELD LDLT group, despite being at higher risk for pulmonary infection, abdominal fluid collection and prolonged ICU stay. The data, primarily sourced from high-volume Asian centers, underscore the feasibility of living donations for liver allografts in high-MELD patients. Given the rising demand for liver allografts, it is sensible to incorporate these insights into U.S. transplant practices.

Mechanisms of the ascites volume differences between patients receiving a left or right hemi-liver graft liver transplantation: From biofluidic analysis

BACKGROUND AND OBJECTIVE

Post-transplant refractory ascites (RA) is common in patients receiving living donor liver transplantation (LDLT) using a left hemi-liver graft than in those using a right hemi-liver graft. However, there is currently no clear mechanism explaining the effect of grafts on ascites drainage. The purpose of this study is to analyze the values of blood flow parameters in the portal vein under different grafts using computational fluid dynamics (CFD) to interpret the relationship between portal pressure values with ascites drainage.

METHODS

In this work, ascites drainage was counted in 30 patients who underwent left-sided liver transplantation and 26 patients who underwent right-sided liver transplantation. The portal vein flow models of the transplanted liver under different flow rates were established based on computed tomography (CT) images and finite element theory. Ascites drainage and blood flow parameters were qualitatively compared.

RESULTS

The results show that the ascites drained from patients who received LDLT with a left hemi-liver is three times as that with a right hemi-liver. The simulation results show that the coefficient of the pressure-velocity curve of the left-liver is 1.7 times of the right-liver under the same hydrodynamic conditions, which qualitatively agrees with the clinical data. Moreover, the streamline of the transplanted left liver shows more vortexes compared with the right liver, which is a major reason for the left liver's higher pressure value.

CONCLUSION

This clinical phenomenon is reproduced and comprehensively explained by the hemodynamic parameters of the portal vein. This work establishes the relationship between portal pressure values and floating water drainage, and offers a new way for physicians to predict postoperative risks intuitively.

An exploratory analysis of patient factors influencing acceptance of extended criteria liver grafts

INTRODUCTION AND OBJECTIVES

There is a shortage of ideal donor organs with consequential increasing waitlist times, drop-off, and mortality. Teams have thus extended the donor criteria. Little is known about patients' actual choices and what factors may influence their decisions regarding different extended criteria liver grafts.

PATIENTS AND METHODS

The documented acceptance or refusal of seven extended criteria liver graft types of patients consented for transplant in a single institution over a 2-year period was reviewed. Patient factors including sex, age, indication, aetiology, and model for end-stage liver disease (MELD) score were analysed using logistic regression.

RESULTS

Most patients were willing to accept most graft types. MELD score did not impact the acceptance or refusal of any graft type. Older patients and those with hepatocellular carcinoma (HCC) or ascites had significantly higher rates of acceptance. Hepatitis B or C disease aetiology was predictive of willingness to accept a similarly infected graft, respectively. HCC was predictive of acceptance of grafts from donors with a cancer history.

CONCLUSIONS

In general, patients embrace the available extended criteria donors. Our analysis suggests that consent should be revisited as patients deteriorate or ameliorate on the waitlist, especially if in the form of ascites or HCC but not necessarily MELD score.

BETTER LIVING DONOR LIVER TRANSPLANTATION PATIENT SURVIVAL COMPARED TO DECEASED DONOR — A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT Background Deceased donor liver transplantation (DDLT) is the first choice, but living donor transplantation (LDLT) is an alternative to be considered in special situations, such as lack of donated organs and emergencies. So far, there is no consensus on which transplantation method provides better survival and fewer complications, which is still an open point for discussion. Methods This meta-analysis compared the 1, 3, and 5-year patient and graft survival rates of LDLT and DDLT. We included studies published from April-2009 to June-2021 and adopted the generic model of the inverse of variance for the random effect of hazard ratios. The adequacy of the studies was determined using the Newcastle-Ottawa Scale — NOS (WELLS). Results For patient survival analysis, we included a total of 32,258 subjects. We found a statistically significant better survival for the LDLT group at 1, 3 and 5 years, respectively: 1.35 HR (95%CI 1.10—1.66, P=0.005), 1.26 HR (95%CI 1.09—1.46, P=0.002) and 1.27 HR (95%CI 1.09—1.48, P=0.002). Our meta-analysis evaluated a total of 21,276 grafts. In the overall analysis, the 1-year survival was improved in favor of the LDLT group (1.36 HR, 95%CI 1.16—1.60, P<0.0001), while the 3-year survival (1.13 HR, 95%CI 0.96—1.33, P<0.13), and 5 (0.99 HR, 95%CI 0.74—1.33, P<0.96), did not differ significantly. Conclusion This metanalysis detected a statistically significant greater 1-, 3- and 5-years patient survival favoring LDLT compared to DDLT as well as a statistically significant difference better 1-year graft survival favoring the LDLT group.

The Classification of Biliary Strictures in Patients With Right-Lobe Liver Transplant Recipients and Its Relation to Traversing the Stricture With a Guidewire

BACKGROUND

Traversing the stricture with a guidewire is a prerequisite for the endoscopic treatment of biliary strictures after living donor liver transplantation. We aimed to evaluate the effect of variations in the biliary anastomosis and strictures on the success of endoscopic treatment and suggest a cholangiographic classification.

METHODS

The 125 strictures among the 104 patients with right-lobe living donor liver transplantation were reviewed. The strictures were classified by the anastomosis pattern according to the number (1, 2, or >2), location (common bile, hepatic, or cystic duct), the angle between the proximal and distal sites of the anastomosis, and the contrast enhancement pattern. The relationship between the success rate of traversing the anastomosis and the classification was evaluated.

RESULTS

Of the 125 biliary strictures, 86 (68.8%) could be passed via endoscopically. Thirty-three strictures were managed either percutaneously (n = 13) or by magnetic compression anastomosis (n = 20). Compared with the round, the triangular (odds ratio [OR], 6.5), the intermediate form (OR, 17.7), and the end-to-side anastomosis (OR, 5.1) were associated with an increased chance of traversing. The contrast enhancement pattern of the strictures and the bile ducts was also related to the successful rate of the endoscopic treatment (P < 0.001). The success rate was higher in the patients with the angle between the proximal and distal sites of the anastomosis approximated was small (0°-30° = 74%, 30°-60° = 69%, 60°-90° = 63%, >90° = 41%).

CONCLUSIONS

The type of biliary anastomoses and stricture affect the success rate of endoscopic treatment. These data may play role in making decision about the type of anastomosis during the surgery.

Nature of the liver volume depending on the gender and age assessing volumetry from a reconstruction of the computed tomography

Although the liver is a regenerating organ, excessive loss of liver volume (LV) can cause fatal liver failure. It is unclear whether LV is correlated with age; however, it is known that liver function decreases with age. In addition, the gender-related role of LV remains unclear. This study aimed to investigate the changes in LV by age and gender. Between January and December 2018, 374 consecutive patients who underwent abdominal multidetector computed tomography (MDCT) for any abdominal examinations were enrolled. LV was evaluated using MDCT. The relationship between the LV and body mass index (BMI), body surface area (BSA), age, and gender was investigated. The modified LV (mLV) was calculated by a formula measured LV × 1.5/BSA. LV correlated to BSA more than to BMI in both the males (R: 0.559 vs. 0.416) and females (R: 0.479 vs. 0.300) in our study. Age was negatively correlated to LV and BSA, and correlated to LV more than to BSA in males (R: 0.546 vs. 0.393) and females (R: 0.506 vs. 0.385). In addition, the absolute slope between age and LV in the males was higher than that in the females (14.1 vs. 10.2, respectively). Furthermore, the absolute slope of age and mLV in the males was slightly higher than in the females (9.1 vs. 7.3, respectively). In conclusion, LV in the normal liver is correlated to age rather than the one in the diseased liver. Liver volume in the males decreased more with age than LV in the females.

Meta-analysis and meta-regression of outcomes for adult living donor liver transplantation versus deceased donor liver transplantation

Prior single center or registry studies have shown that living donor liver transplantation (LDLT) decreases waitlist mortality and offers superior patient survival over deceased donor liver transplantation (DDLT). The aim of this study was to compare outcomes for adult LDLT and DDLT via systematic review. A meta-analysis was conducted to examine patient survival and graft survival, MELD, waiting time, technical complications, and postoperative infections. Out of 8600 abstracts, 19 international studies comparing adult LDLT and DDLT published between 1/2005 and 12/2017 were included. U.S. outcomes were analyzed using registry data. Overall, 4571 LDLT and 66,826 DDLT patients were examined. LDLT was associated with lower mortality at 1, 3, and 5 years posttransplant (5-year HR 0.87 [95% CI 0.81-0.93], p < .0001), similar graft survival, lower MELD at transplant (p < .04), shorter waiting time (p < .0001), and lower risk of rejection (p = .02), with a higher risk of biliary complications (OR 2.14, p < .0001). No differences were observed in rates of hepatic artery thrombosis. In meta-regression analysis, MELD difference was significantly associated with posttransplant survival (R2 0.56, p = .02). In conclusion, LDLT is associated with improved patient survival, less waiting time, and lower MELD at LT, despite posing a higher risk of biliary complications that did not affect survival posttransplant.

Adult split liver transplantation: A PRISMA-compliant Chinese single-center retrospective case-control study

Although pediatric split liver transplantation (SLT) has been proven safe and the waitlist mortality rate has been successfully reduced, the safety of adult SLT has not been confirmed.Using 1:2 matching, 47 recipients who underwent adult SLT were matched to 94 of 743 recipients who underwent adult whole graft liver transplantation (WGLT). Eventually, 141 recipients were included in the case-control study. Subgroup analysis of 43 recipients in the SLT group was performed based on the presence of the middle hepatic vein (MHV) in the grafts.No significant differences in 5-year survival (80.8% vs 81.6%, P = .465) were observed between the adult SLT and WGLT groups. However, compared to recipients in the WGLT group, those in the SLT group had more Clavien-Dindo grade III-V complications, longer hospitalization duration, and higher mortality within 45 days. Furthermore, on multivariate analysis, 45-day postoperative mortality in recipients in the SLT group was mainly affected by hyperbilirubinemia within postoperative day (POD) 7-14, surgery time, and intraoperative blood loss. Subgroup analysis showed no significant differences in hyperbilirubinemia within POD 7-14, complications, and survival rate between SLTMHV(+) and SLTMHV [-].Adult SLT is safe and effective based on long-term survival rates; however, a reduction in the incidence of short-term complications is required. Non-obstructive hyperbilirubinemia within POD 7 to 14 is an independent predictor of short-term mortality after SLT.

Short-term and long-term outcomes in living donors for liver transplantation: Cohort study

BACKGROUND

Although perioperative outcomes following donor hepatectomy (DH) have been reported, little is known about the long-term outcomes in living donors of liver transplantation. The aim of this study was to investigate the short-term and long-term outcomes following DH.

METHODS

A total of 408 living donors who underwent DH between 1996 and 2019 were analyzed in this retrospective study, focusing on short-term outcomes with respect to the operation period (era) and the graft type, as well as long-term outcomes.

RESULTS

The overall incidence of postoperative complications was 40.4%. These included minor (30.4%), major (10.0%), and biliary (14.0%) complications. Short-term outcomes after DH slightly improved over time, and outcomes did not differ significantly between the graft types. With regards to long-term outcomes, the incidence of surgery-related complications such as keloids, incisional hernias, and mechanical bowel obstructions was 6.6% over a median follow-up of 7.2 years. In addition, some donors developed comorbidities such as lifestyle diseases and cancers during the follow-up period.

CONCLUSIONS

Our study confirmed an improvement of perioperative outcomes in living donors. There was no significant association between the graft type and postoperative outcomes. Donors could develop various morbidities during long-term follow-up. Therefore, a careful perioperative management and long-term follow-up should be provided to living donors.

Recovery of the Psoas Muscle Index in Living Donors after a Right Lobe Hepatectomy for Liver Transplantation: A Single-Center Experience

OBJECTIVE

The development of sarcopenia leads to adverse postoperative outcomes. However, no study has investigated perioperative loss in core muscle and the correlation between core muscle and residual liver volume in living donors for liver transplant.

PATIENTS AND METHODS

A total of 457 adult healthy donors who underwent a right lobe hepatectomy without the middle hepatic vein for elective liver transplant were retrospectively analyzed. Abdominal computed tomography was performed within 1 month before surgery and the first week and 3 months after the surgery. The average psoas muscle area between lumbar vertebrae 3 and 4 was measured and normalized by height squared (psoas muscle index [PMI] = psoas muscle area/height²). The initial whole liver volume and remnant left lobe volume were measured on computed tomography images.

RESULTS

The study cohort included 279 men (61.1%) and 178 women (38.9%). The median preoperative PMIs were 420.9 mm²/m² (interquartile range, 360.6-487.0 mm²/m²) in men and 280.9 mm²/m² (interquartile range, 243.5-318.7 mm²/m²) in women. The PMIs in men and women significantly decreased during the first week after surgery, and gradually recovered to preoperative levels during the first 3 months after surgery. Based on the ratio between the remnant left lobe and initial whole liver volume (≥30%), the increase in remnant left lobe volume was not correlated with the decrease in PMI on postoperative day 7. A postoperative U-shaped recovery in the core muscles was present in both male and female donors, independent of the remnant liver ratio.

CONCLUSIONS

Despite the requirements of partial liver regeneration and surgical wound repair, healthy donors did not suffer from sustained core muscle loss after surgery.