Machine learning in liver surgery:Benefits and pitfalls

The application of machine learning(ML)algorithms in various fields of hepatology is an issue of interest.However,we must be cautious with the results.In this letter,based on a published ML prediction model for acute kidney injury after liver surgery,we discuss some limitations of ML models and how they may be addressed in the future.Although the future faces significant challenges,it also holds a great potential.

Machine perfusion and the prevention of ischemic type biliary lesions following liver transplant:What is the evidence?

The widespread uptake of different machine perfusion(MP)strategies for liver transplant has been driven by an effort to minimize graft injury.Damage to the cholangiocytes during the liver donation,preservation,or early posttransplant period may result in stricturing of the biliary tree and inadequate biliary drainage.This problem continues to trouble clinicians,and may have catastrophic consequences for the graft and patient.Ischemic injury,as a result of compromised hepatic artery flow,is a well-known cause of biliary strictures,sepsis,and graft failure.However,very similar lesions can appear with a patent hepatic artery and these are known as ischemic type biliary lesions(ITBL)that are attributed to microcirculatory dysfunction rather than main hepatic arterial compromise.Both the warm and cold ischemic period duration appear to influence the onset of ITBL.All of the commonly used MP techniques deliver oxygen to the graft cells,and therefore may minimize the cholangiocyte injury and subsequently reduce the incidence of ITBL.As clinical experience and published evidence grows for these modalities,the impact they have on ITBL rates is important to consider.In this review,the evidence for the three commonly used MP strategies(abdominal normothermic regional perfusion[A-NRP],hypothermic oxygenated perfusion[HOPE],and normothermic machine perfusion[NMP])for ITBL prevention has been critically reviewed.Inconsistencies with ITBL definitions used in trials,coupled with variations in techniques of MP,make interpretation challenging.Overall,the evidence suggests that both HOPE and A-NRP prevent ITBL in donated after circulatory death grafts compared to cold storage.The evidence for ITBL prevention in donor after brain death grafts with any MP technique is weak.

Short-term outcomes of robotic liver resection: An initial singleinstitution experience

BACKGROUND Liver surgery has traditionally been characterized by the complexity of its procedures and potentially high rates of morbidity and mortality in inexperienced hands.The robotic approach has gradually been introduced in liver surgery and has increased notably in recent years.However,few centers currently perform robotic liver surgery and experiences in robot-assisted surgical procedures continue to be limited compared to the laparoscopic approach.AIM To analyze the outcomes and feasibility of an initial robotic liver program implemented in an experienced laparoscopic hepatobiliary center.METHODS A total of forty consecutive patients underwent robotic liver resection(da Vinci Xi,intuitive.com,United States)between June 2019 and January 2021.Patients were prospectively followed and retrospectively reviewed.Clinicopathological characteristics and perioperative and short-term outcomes were analyzed.Data are expressed as mean and standard deviation.The study was approved by the Institutional Review Board.RESULTS The mean age of patients was 59.55 years,of which 18(45%)were female.The mean body mass index was 29.41 kg/m^(2).Nine patients(22.5%)were cirrhotic.Patients were divided by type of resection as follows:Ten segmentectomies,three wedge resections,ten left lateral sectionectomies,six bisegmentectomies(two VVI bisegmentectomies and four IVb-V bisegmentectomies),two right anterior sectionectomies,five left hepatectomies and two right hepatectomies.Malignant lesions occurred in twenty-nine(72.5%)of the patients.The mean operative time was 258.11 min and two patients were transfused intraoperatively(5%).Inflow occlusion was used in thirty cases(75%)and the mean total clamping time was 32.62 min.There was a single conversion due to uncontrollable hemorrhage.Major postoperative complications(Clavien–Dindo>Ⅲb)occurred in three patients(7.5%)and mortality in one(2.5%).No patient required readmission to the hospital.The mean hospital stay was 5.6 d.CONCLUSION Although robotic hepatectomy is a safe and feasible procedure with favorable short-term outcomes,it involves a demanding learning curve that requires a high level of training,skill and dexterity.