Graft To Body Weight Ratio Research Articles

Robotic surgery and liver transplantation: A single-center experience of 501 robotic donor hepatectomies

BackgroundOver the past two decades robotic surgery has been introduced to many areas including liver surgery. Laparoscopic liver surgery is an alternative minimally invasive approach. However, moving on to the complexity of living donor hepatectomies, the advantages of robotic versus laparoscopic approach have convinced us to establish the robotic platform as a standard for living donor hepatectomy. MethodsFrom November 2018 to January 2022, 501 fully robotic donor hepatectomies, including 177 left lateral donor lobes, 112 full left lobes and 212 full right lobes were performed. Grafts were donated to 296 adult recipients and 205 pediatric recipients. Donor age, sex, body weight, body mass index (BMI), graft weight, graft to body weight ratio (GBWR), operative time, blood loss, first warm ischemic time, pain score, length of intensive care unit (ICU) stay and hospital stay, and complications were retrospectively analyzed based on a prospectively kept database. Recipients were evaluated for graft and patient survival, age, sex, BMI, body weight, model of end-stage liver disease score, blood loss, transfusions, operative time, cold ischemic time, length of hospital stay and complications. ResultsThere was no donor mortality. Two cases needed to be converted to open surgery. The median blood loss was 60 mL (range 20-800), median donor operative time was 6.77 h (range 2.93-11.53), median length of hospital stay was 4 days (range 2-22). Complication rate in donors classified following Clavien-Dindo was 6.4% (n = 32) with one grade III complication. Three-year actual recipient overall survival was 91.4%; 87.5% for adult recipients and 97.1% for pediatric recipients. Three-year actual graft overall survival was 90.6%; 87.5% for adult recipients and 95.1% for pediatric recipients. In-hospital mortality was 6%, 9.1% (27/296) for adult recipients and 1.4% (3/205) for pediatric recipients. The recipients’ morbidity was 19.8% (n = 99). Twenty-eight recipients (5.6%) had biliary and 22 (4.4%) vascular complications. Six (12.0%) recipients needed to be re-transplanted. ConclusionsWith growing experience it is nowadays possible to perform any donor hepatectomy by robotic approach regardless of anatomical variations and graft size. Donor morbidity and quality for life results are encouraging and should motivate other transplant centers with interest in minimally invasive donor surgery to adopt this robotic technique.

Left-liver Adult-to-Adult Living Donor Liver Transplantation: Can It Be Improved? A Retrospective Multicenter European Study.

To evaluate the European experience after Adult-to-adult living donor liver transplantation using the left liver (LL-aLDLT). LL-aLDLT decreases donor risk but provides a smaller graft that increases recipient risk as compared with right liver (RL-aLDLT). However, there is little knowledge of results obtained after LL-aLDLT in Europe. This is a European multicenter retrospective study which aims to analyze donor and recipient outcomes after 46 LL-aLDLT. Seventy-six percent of the grafts were harvested by minimally invasive approach. Mean donor hospital stay was 7.5 ± 3.5 days. Donor liver function was minimally impaired, with 36 donors (78.3%) without any 90-day complication, and 4 (8.7%) presenting major complications. One, 3, and 5-year recipient survival was 90.9%, 82.7%, and 82.7%, respectively. However, graft survival was of 59.4%, 56.9%, and 56.9% at 1, 3, and 5 years respectively, due to a 26.1% urgent liver retransplantation (ReLT) rate, mainly due to SFSS (n = 5) and hepatic artery thrombosis (HAT, n = 5). Risk factor analysis for ReLT and HAT showed an association with a graft to body weight ratio (GBWR) <0.6% (P = 0.01 and P = 0.024, respectively) while SFSS was associated with a recipient MELD ≥14 (P = 0.019). A combination of donor age <45 years, MELD <14 and actual GBWR >0.6% was associated with a lower ReLT rate (0% vs. 33%, P = 0.044). Our analysis showed low donor morbidity and preserved liver function. Recipient outcomes, however, were hampered by a high ReLT rate. A strict selection of both donor and recipients is the key to minimize graft loss.

Using Small-for-Size Grafts in Living Donor Liver Transplantation Recipients with High MELD Scores Should Not Be Considered a Contraindication

The model for end-stage liver disease (MELD) system is a good tool to predict short-term mortality among living donor liver transplantation (AALDLT) recipients and has also been suggested to prohibited live liver donation for recipients with MELD scores[25 [1]. A partial liver graft transplanted into an adult recipient is often defined as a small-for-size graft. It is generally accepted that such graft would be tolerated when the graft-to-body weight ratio (GBWR) is higher than 0.8. However, transplanted liver will suffer small-for-size syndrome (SFSS) and irreversible damage when GBWR \0.8. In AALDLT, graft size and pre-transplant MELD scores are important factors for patient post-transplant survival [2]. Here we evaluated the outcome of using a SFSG in AALDLT recipients with different MELD scores in a single liver transplant center. Clinical data of 118 patients who had right-lobe AALDLT from January 2004 to December 2011 were retrospectively analyzed. According to MELD, patients were divided into group L (MELD score B25, n = 102) and group H (MELD score [25, n = 16). To analyze the risk of the graft size, the patients were further stratified into group LS (MELD score B25, GBWR\0.8, n = 23), group LN (MELD score B25, GBWR C0.8, n = 79), group HS (MELD score [25, GBWR \0.8, n = 5), and group HN (MELD score [25, GBWR C0.8, n = 11). MELD scores between the two groups were significantly different. There was no significant difference in preoperative demographic data as well as postoperative liver function data. The length of ICU and hospital stay, graft loss, and mortality were similar in both groups. Complication rate was also similar between two groups (10.8 vs 6.3 %, P = 1.000). The 1and 3-year survival rate were similar between group L and group H (85.2 vs 74 %, 78.9 vs 74 %, P = 0.692). After stratified into groups LS, LN, HS, and HN, there were no significant differences among groups in 1and 3-year survival rate. Multivariate analysis revealed that accompanied hepatocellular carcinoma (HCC), GBWR, and MELD scores did not predict the 1and 3-year survival rate. Recipients with high MELD scores usually have worse preoperative conditions and experience a more complicated peri-operative course. However, there are still debates on this subject. Hayashi et al. [3] reported that there was no correlation between the 1-year survival rate and MELD scores. According to Yi et al. [4], the 1-year survival rate without HCC was found to be similar between those two groups as well as the rate of postoperative complications. In our report, the postoperative complication rate, ICU and hospital stay length after AALDLT did not differ between recipients. Pneumonia was still the first cause of death. We attributed these advanced results to a high level of perioperative intensive care for high MELD score recipients. When using a graft with GBWR less than 0.8 in AALDLT, recipients possibly suffer postoperative irreversible liver damage. However, Yi et al. [4] also reported that a high MELD score ([25) was not an important predictor of the 1-year survival rate in cases with an SFSG. Reconstruction of the MHV is well known as an important factor to reduce the incidence of graft failure in an SFSG. In our study, although there was no significant difference in survival rates among groups with versus without MHV, we might H. Li B. Li (&) Department of Liver and Vascular Surgery, Center of Liver Transplantation, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China e-mail: doclibo@126.com

Using tacrolimus in living donor liver transplantation recipients with high model for end-stage liver disease scores might increase the risk of postoperative neuropsychologic deficits

For decompensated liver cirrhosis and hepatocellular carcinoma, liver transplantation provides these patients the only curative treatment option with better long-term results. The Model for End-stage Liver Disease (MELD) system is a good tool to predict short-term mortality among these patients and has also been applied to allocate liver grafts to patients on waiting lists in several countries.1 In 2002, the New York State Committee on Quality Improvement in Living Liver Donation prohibited live liver donation for potential recipients with MELD scores greater than 25.2 Alves et al suggested MELD scores >18 was associated with higher probability of graft failure after living donor liver transplantation (LDLT).3 Previous studies have demonstrated that using tacrolimus as primary immunosuppressant, neuropsychologic deficits had been found to be higher in recipients with elevated preoperative MELD scores, especially for those MELD scores greater than 15.4,5 We here summarize our experiences on postoperative neuropsychologic deficits in LDLT recipients using tacrolimus with high MELD scores. From 2004 to 2012, 218 LDLT were performed in our transplant center. Postoperative neuropsychologic deficits were observed in 8 male recipients (3.7%) during the first week, including: insomnia (2), vivid dreams (1), paresthesias (1), anxiety (1), agitation (2), and cognitive impairment (1). The mean age was 42 (33-57) and the mean MELD score was 21 (9-28). All of the patients did not have the history of excessive alcohol use and preexisting central nervous system damage. Decompensated liver cirrhosis caused by HBV infection was seen in 5 patients, while hepatocellular carcinoma (HCC) was seen in 3 patients. Right living lobe liver transplantations were performed by the same medical team, with a mean graft to body weight ratio (GBWR) 0.78 (0.6-1.0). Our center used tacrolimus as the initial immunosuppressant for all liver transplant recipients. In the first postoperative week, the mean tacrolimus blood level was 9.3 (6.511.6), while the mean total bilirubin blood level was 23mmol/L (15-30mmol/L), the mean creatinine blood level was 67umol/L (45-90umol/L), and the mean serum sodium level was 139mmol/L (136-143mmol/L). The mean ICU stays was 9 days (7-12 days). After switching tacrolimus to sirolimus, all recipients were relieved from neuropsychlologic deficits and discharged eventually without primary graft non-function, renal failure, acute rejection, re transplantation or death. All the 8 recipients had a relatively higher MELD scores to other LDLT recipients. Although the mechanistic pathway resulting in these neural deficits is not clear, our hypothesis is that several reasons might contribute to it: 1) elevated preoperative MELD scores usually represents a poor liver function, potential encephalopathy risk, and increased susceptibility to blood-brain barrier disruption, associating with increased vulnerability to postoperative tacrolimus neurotoxicity; 2) when GBWR <0.8, a small-for-size (SFS) living graft recipients have significantly decreased tacrolimus dosage requirements compared with non-SFS grafts recipients in LDLT. A regular dosage may cause higher tacrolimus blood levels in these SFS graft recipients and elevated blood levels of tacrolimus are associated with neurotoxicity6; 3) in order to ensure the donor safety, a SFS graft may be transplanted to a high MELD recipient. This interaction may apparently increase the postoperative neuropsychologic deficits risk in such group of patients. Although the switching from tacrolimus to sirolimus can effectively relieve patients’ neuropsychlologic deficits, there are potential risks in graft primary non-function, infection, and 1. Hongyu Li, 2. Bo Li, PhD, MD, 3. Yonggang Wei, MD, 1-3: Department of Liver and Vascular Surgery, Center of Liver Transplantation, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.

Using a Small-For-Size Graft Might Attribute to the Future Use of Left-Lobe Living Graft in Adult to Adult Living Donor Liver Transplantation

Adult to adult living donor liver transplantation (AALDLT) is performed worldwide. The aim of this study was to evaluate using a graft with graft to body weight ratio (GBWR) less than 0.8 in right-lobe AALDLT recipients. Clinical data of 127 patients who had right-lobe AALDLT from January 2002 to November 2009 were retrospectively analyzed. Patients were divided into two groups according to GBWR (group A: 0.6 ≤ GBWR < 0.8, group B: GBWR ≥ 0.8). Preoperative characteristics, postoperative complications graded by the Clavien score and patient survival time were recorded and analyzed. GBWR between the two groups were significantly different (0.67 ± 0.05 vs. 0.97 ± 0.17, p = 0.000). There was no significant difference in preoperative demographic data as well as postoperative liver function data. Complication rate, median ICU stay and small-for-size syndrome incidence were similar in both groups. In univariate analysis, only MELD emerged as independent risk factor for small-for-size syndrome (p = 0.045). Patient survival was similar in both groups at 1, 3 and 5 years as well. Using a GBWR of less than 0.8 is safe in selected recipients. To some extent, this result may attribute to the wide use of left-lobe living graft in AALDLT in future.

Safety of Patients with a Graft to Body Weight Ratio Less than 0.8% in Living Donor Liver Transplantation using Right Hepatic Lobe without Middle Hepatic Vein

This study aimed to evaluate the postoperative outcomes of patient with a graft with graft to body weight ratio (GBWR) less than 0.8% after living donor liver transplantation (LDLT) using the right hepatic lobe without middle hepatic vein (MHV). The clinical data of patients who underwent LDLTs using the right hepatic lobe without the MHV, between March 2006 and April 2009, were retrospectively analyzed. Patients were divided into two groups according to the GBWR (group A, GBWR <0.8%; group B, GBWR =0.8%). Preoperative characteristics were statistically analyzed. Postoperative complications were classified by the Clavien classification. The Kaplan-Meier survival analysis with logrank test was used to compare the long-term survival of two groups. The two groups were comparable. Similar incidence of serious postoperative surgical complication (grade =3) was observed between the two groups. The 1-, 3- and 4-year survival rates of the two groups were 81%, 64% and 57%, and 83%, 71% and 64%, respectively. No significant differences were observed. Small-forsize graft (GBWR <0.8%) can be safely used in adult to- adult LDLT using right hepatic lobe without MHV.

A graft to body weight ratio less than 0.8 does not exclude adult-to-adult right-lobe living donor liver transplantation

Many centers require a minimal graft to body weight ratio (GBWR) >or= 0.8 as an arbitrary threshold to proceed with right-lobe living donor liver transplantation (RL-LDLT), and there is often hesitancy about transplanting lower volume living donor (LD) liver grafts into sicker patients. The data supporting this dogma, based on the early experience with RL-LDLT at Asian centers, are weak. To determine the effect of LD liver volume in the modern era, we investigated the impact of GBWR on the outcome of RL-LDLT with a GBWR as low as 0.6 at the University of Toronto. Between April 2000 and September 2008, 271 adult-to-adult RL-LDLT procedures and 614 deceased donor liver transplants were performed. Twenty-two living donor liver transplantation (LDLT) cases with a GBWR of 0.59 to 0.79 (group A) were compared with 249 LDLT cases with a GBWR >or= 0.8 (group B) and with 66 full-graft deceased donor liver transplants (group C), who were matched 3:1 according to donor and recipient age, Model for End-Stage Liver Disease score, and presence of hepatitis C and hepatocellular carcinoma with the low-GBWR group. Portal vein shunts were not used. Markers of reperfusion injury [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], graft function (international normalized ratio and bilirubin), complications graded by the Clavien score, and graft and patient survival were compared. As expected, LD recipients had a significantly shorter cold ischemia time (94 +/- 43 minutes for A, 96 +/- 57 minutes for B, and 453 +/- 152 minutes for C, P = 0.0001). However, the peak AST, peak ALT, absolute decrease in the international normalized ratio, day 7 bilirubin level, postoperative creatinine clearance, complication rate graded by the Clavien score, and median hospital stay were similar in all groups. The rate of biliary complications was higher with LD grafts than deceased donor grafts (19% for A versus 10% for B and 0% for C, P = 0.2). Patient survival was similar in all groups at 1, 3, and 5 years (91% for A versus 89% for B and 93% for C at 1 year, 87% for A versus 81% for B and 89% for C at 3 years, and 83% for A versus 81% for B and 87% for C at 5 years, P = 0.63). A Cox proportional regression analysis revealed only hepatitis C virus as a risk factor for poorer graft survival and not GBWR as a continuous or categorical variable. In conclusion, we found no evidence of inferior outcomes with smaller size grafts versus larger size LD grafts or full-size deceased donor grafts. Further studies are warranted to examine the factors affecting the function of smaller grafts for living liver donation and thereby define the safe lower limits for transplantation.

Higher Graft-to-Host Ratio May Decrease Posttransplant Mortality in Patients With a High MELD Score

The aim of this study was to determine whether scores from the model for end-stage liver disease (MELD) can be used in the preoperative strategic planning of transplantation surgery. We retrospectively analyzed the outcomes of 62 adult liver transplantation patients whose operation was performed at our center between January 2001 and June 2006. All patients had MELD scores between 8 and 35 with an average value of 20. We compared postoperative mortality among patients who had MELD scores higher than 20 as determined by their graft-to-host ratios. We separately grouped the patients whose graft-to-body weight ratio (GBWR) was equal to or lower than 1 and whose GBWR was higher than 1. The GBWRs associated with mortality after living-donor liver transplantation in the early postoperative period were considered significant ( P = .005). MELD scores were also found to be associated with mortality ( P = .006). Mortality rates in patients with high MELD scores and a low GBWR were highest among the other combinations. In conclusion, we found that GBWR lower than 1 and MELD score higher than 20 are significant risk factors for mortality after living donor liver transplantation. Patients with low MELD scores can undergo transplantation when their GBWR is lower than 1, but recipients with high MELD scores should receive grafts only when their GBWR is higher than 1.

CHOLESTASIS AFTER REDUCED LIVER TRANSPLANTATION. COMPARASION TO CADAVERIC LIVER TRANSPLANTATION.

A156 Split and living donor liver transplantation in adults have emerged as good alternatives to the increasing donor shortage. In reduced liver transplantation, early cholestasis is a frequent clinical problem with confusing etiology and prognosis. Aim: The aim of this study was to compare the incidence of cholestasis in a series of reduced liver graft recipients with one of cadaveric whole liver transplant recipients. Material and Methods: From March 2000 to December 2003, 40 reduced liver transplants (RLT) with a mean graft to body weight ratio (GBWR) of 1.11±0.24 were performed in our Hospital. RLT was retrospectively compared with 80 cadaveric liver transplants (CLT) performed immediately before and after each RLT. Total bilirrubin (Bb), alkaline phosphatase (AP) and gammaGT(GGT) were mesured daily during the first week and three times a week until hospital discharge. Liver biopsy was performed when graft dysfunction occured. Cholestasis was defined as the presence of at least two of the following criteria, in the absence of acute liver rejection or hepatitis C virus recurrence: Bb > 3 mg/dl, or AP > 600 UI, or GGT > 300 UI. Results: No differences were found in either group regarding recipients’ age, sex, diagnosis and Child-Pough score, both groups were comparable except for cold ischemia time (91±45 min in CLT vs 353±131 min in RLT, p<0.05)) and donor age (33±8 years in RLT vs 45±10 years in CLT, p<0.05). During the follow-up, a significant higher biliary complication rate was found in the RLT group in comparison with CLT group (53.8% vs 12.9%, p<0.05). Incidence of cholestasis was higher in the RLT group when compared to the CLT group (48.5% vs 25.4%, p<0.05) Mean AP and GGT were significantly higher in the RLT group. (705±476 vs 483±304, p<0.05 and 470±376 vs 268±230, p<0.05). No difference in cholestasis was found when recipients of the RLT group were divided into two groups according to the presence or absence of biliary complications (46.7% vs 64.7%, p=ns). Furthermore, no correlation was found in the RLT group between cholestasis and GBWR, blood portal flow, cold ischemia time or Child-Pugh classification. Conclusion: Cholestasis is more frequent in recipients underwent reduced liver transplantation and this doesn’t seem to correlate with occurrence of biliary complications, more frequently found in these procedures.

Changes in portal vein flow after adult living-donor liver transplantation: Does it influence postoperative liver function?

In adult living donor liver transplantation, using small grafts in cirrhotic patients with severe portal hypertension may have unpredictable consequences. The so-called small-for-size syndrome is present in most series worldwide. The goal of this study was to prospectively evaluate the influence of hemodynamic changes on postoperative liver function and on the percentage of liver volume increase, in the setting of living donor liver transplantation. Twenty-two consecutive adult living donor liver transplantations were performed at our institution in a 2-year period. We measured right portal flow and right hepatic arterial flow with an ultrasonic flow meter in the donor, and then in the recipient 1 hour after reperfusion. Postoperative liver function was measured by daily laboratory work. We also performed duplex ultrasounds on postoperative days 1, 2, and 7. Liver volume increase was estimated by magnetic resonance imaging graft volumetry at 2 months posttransplantation. We compared the blood flow results with the immediate liver function and its liver volume increase rate at 2 months. There was a significant increase in portal flow in the recipients compared with the donors (up to fourfold in some cases). Higher portal flow increase rates significantly correlated with faster prothrombin time normalization and faster liver volume increases. Median graft volume increase at 2 months was 44.9%. The increase in blood flow to the graft is well tolerated by the liver mass not affecting hepatocellular function as long as the graft-to body weight ratio is maintained (>0.8) and adequate outflow is provided. (Liver Transpl 2003;9:564-569.)