Analysis of factors associated with discrepancies between predicted and observed liver weight in liver transplantation

Graft reduction in adult liver transplantation: indications, techniques, and outcomes

PURPOSE

Graft reduction can be a patient's graft-saving option to avoid large-for-size (LFS) syndrome. This study aimed to summarize the literature on graft reduction in adult liver transplantation and to demonstrate the technique of H67 graft hepatectomy.

METHODS

The technique, shown in a didactical video, entails an ex situ posterior sectionectomy under hypothermic perfusion. The right hepatic vein is identified, and the transection line follows the right hepatic fissure. The Glissonean pedicles are ligated during parenchymal transection.

RESULTS

A narrative review of the literature yielded 7 studies. A total of 15 liver grafts were reduced in adult liver transplantations. Most of the reductions were ex situ (11/15 [73.3%]). Graft reduction entailed an H67 sectionectomy in 10 cases and an H23 sectionectomy in 1 case. In situ reduction included 1 right hepatectomy (H5678), 2 H67 sectionectomies, and 1 H23 left lateral sectionectomy. The duration of the ex situ reduction averaged 56 minutes (median: 40.5 minutes; IQR, 33.0-130.0), and the graft weight-to-recipient weight ratio decreased from 3.57% ± 0.40% to 2.70% ± 0.50% after graft reduction. The average cold ischemia time was 390 minutes (IQR, 230-570). There was no liver retransplantation.

CONCLUSION

Graft reduction in adult liver transplantation may be necessary to avoid LFS syndrome. Ex-situ H67 posterior sectionectomy represents the easiest graft reduction hepatectomy and is able to minimize the occurrence of graft compression while leaving enough functional liver parenchyma.

Graft weight integration in the early allograft dysfunction formula improves the prediction of early graft loss after liver transplantation

The role of the graft-to-recipient weight ratio (GRWR) in adult liver transplantation (LT) has been poorly investigated so far. The aim is to evaluate the contribution of the GRWR to the well-recognized early allograft dysfunction (EAD) model (i.e., Olthoff model) for the prediction of 90-day graft loss after LT in adults. Three hundred thirty-one consecutive adult patients undergoing LT between 2009 and 2018 at Tor Vergata and Sapienza University in Rome, Italy, served as the Training-Set. The Validation-Set included 123 LTs performed at the Erasmus Medical Center, Rotterdam, the Netherlands. The mEAD model for 90-day graft loss included the following variables: GRWR \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le $$\end{document}≤ 1.57 = 2.5, GRWR \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge $$\end{document}≥ 2.13 = 2.5, total bilirubin ≥ 10.0 mg/dL = 2.0, INR ≥ 1.60 = 2.3, and aminotransferase > 2000 IU/L = 2.2. The mEAD model showed an AUC = 0.74 (95%CI = 0.66–0.82; p < 0.001) and AUC = 0.68 (95%CI = 0.58–0.88; p = 0.01) in the Training-Set and Validation-Set, respectively, outperforming conventional EAD in both cohorts (Training-Set: AUC = 0.64, 95%CI = 0.57–0.72; p = 0.001; Validation-Set: AUC = 0.52, 95%CI = 0.35–0.69, p = 0.87). Incorporation of graft weight in a composite multivariate model allowed for better prediction of patients who presented an aminotransferase peak > 2000 IU/L after LT (OR = 2.39, 95%CI = 1.47–3.93, p = 0.0005). The GRWR is important in determining early graft loss after adult LT, and the mEAD model is a useful predictive tool in this perspective, which may assist in improving the graft allocation process.

The authors' reply: Indispensable discrepancy between predicted graft "volume" and actual graft "weight" in clinical practice in living-donor liver transplantation

We would like to respond to the Letter to the Editor "'GRWR' or 'GV/SLV' in clinical practice in living donor liver transplantation" by Haruki et al, that is a comment on our original article "Which is better to use 'body weight' or 'standard liver weight,' for predicting small-for-size graft syndrome after living-donor liver transplantation?" in Annals of Gastroenterological Surgery.

Predicting the available space for liver transplantation in cirrhotic patients: a computed tomography-based volumetric study

BACKGROUND

Anthropometric parameters (weight, height) are usually used for quick matching between two individuals (donor and recipient) in liver transplantation (LT). This study aimed to evaluate clinical factors influencing the overall available space for implanting a liver graft in cirrhotic patients.

METHODS

In a cohort of 275 cirrhotic patients undergoing LT, we calculated the liver volume (LV), cavity volume (CV), which is considered the additional space between the liver and the right hypocondrium, and the overall volume (OV = LV + CV) using a computed tomography (CT)-based volumetric system. We then chose the formula based on anthropometric parameters that showed the best predictive value for LV. This formula was used to predict the OV in the same population. Factors influencing OV variations were identified by multivariable logistic analysis.

RESULTS

The Hashimoto formula (961.3 × BSA_D-404.8) yielded the lowest median absolute percentage error (21.7%) in predicting the LV. The median LV was 1531 ml. One-hundred eighty-five patients (67.2%) had a median CV of 1156 ml (range: 70-7006), and the median OV was 2240 ml (range: 592-8537). Forty-nine patients (17%) had an OV lower than that predicted by the Hashimoto formula. Independent factors influencing the OV included the number of portosystemic shunts, right anteroposterior abdominal diameter, model for end-stage liver disease (MELD) score > 25, high albumin value, and BMI > 30.

CONCLUSIONS

Additional anthropometric characteristics (right anteroposterior diameter, body mass index) clinical (number of portosystemic shunts), and biological (MELD, albumin) factors might influence the overall volume available for liver graft implantation. Knowledge of these factors might be helpful during the donor-recipient matching.