Decoding the Clavien-Dindo Classification: Artificial Intelligence (AI) as a Novel Tool to Grade Postoperative Complications.

OBJECTIVE: To assess ChatGPT's capability of grading postoperative complications using the Clavien-Dindo classification (CDC) via Artificial Intelligence (AI) with Natural Language Processing (NLP). BACKGROUND: The CDC standardizes grading of postoperative complications. However, consistent, and precise application in dynamic clinical settings is challenging. AI offers a potential solution for efficient automated grading. METHODS: ChatGPT's accuracy in defining the CDC, generating clinical examples, grading complications from existing scenarios, and interpreting complications from fictional clinical summaries, was tested. RESULTS: ChatGPT 4 precisely mirrored the CDC, outperforming version 3.5. In generating clinical examples, ChatGPT 4 showcased 99% agreement with minor errors in urinary catheterization. For single complications, it achieved 97% accuracy. ChatGPT was able to accurately extract, grade, and analyze complications from free text fictional discharge summaries. It demonstrated near perfect performance when confronted with real-world discharge summaries: comparison between the human and ChatGPT4 grading showed a κ value of 0.92 (95% CI 0.82-1) (P<0.001). CONCLUSIONS: ChatGPT 4 demonstrates promising proficiency and accuracy in applying the CDC. In the future, AI has the potential to become the mainstay tool to accurately capture, extract, and analyze CDC data from clinical datasets.

Reliability of Medical Information Provided by ChatGPT: Assessment Against Clinical Guidelines and Patient Information Quality Instrument.

BACKGROUND: ChatGPT-4 is the latest release of a novel artificial intelligence (AI) chatbot able to answer freely formulated and complex questions. In the near future, ChatGPT could become the new standard for health care professionals and patients to access medical information. However, little is known about the quality of medical information provided by the AI. OBJECTIVE: We aimed to assess the reliability of medical information provided by ChatGPT. METHODS: Medical information provided by ChatGPT-4 on the 5 hepato-pancreatico-biliary (HPB) conditions with the highest global disease burden was measured with the Ensuring Quality Information for Patients (EQIP) tool. The EQIP tool is used to measure the quality of internet-available information and consists of 36 items that are divided into 3 subsections. In addition, 5 guideline recommendations per analyzed condition were rephrased as questions and input to ChatGPT, and agreement between the guidelines and the AI answer was measured by 2 authors independently. All queries were repeated 3 times to measure the internal consistency of ChatGPT. RESULTS: Five conditions were identified (gallstone disease, pancreatitis, liver cirrhosis, pancreatic cancer, and hepatocellular carcinoma). The median EQIP score across all conditions was 16 (IQR 14.5-18) for the total of 36 items. Divided by subsection, median scores for content, identification, and structure data were 10 (IQR 9.5-12.5), 1 (IQR 1-1), and 4 (IQR 4-5), respectively. Agreement between guideline recommendations and answers provided by ChatGPT was 60% (15/25). Interrater agreement as measured by the Fleiss κ was 0.78 (P<.001), indicating substantial agreement. Internal consistency of the answers provided by ChatGPT was 100%. CONCLUSIONS: ChatGPT provides medical information of comparable quality to available static internet information. Although currently of limited quality, large language models could become the future standard for patients and health care professionals to gather medical information.

Early removal of drains and lines after liver transplantation to reduce the length of hospital stay and enhance recovery - A systematic review of the literature and expert panel recommendations.

BACKGROUND: The timing of removing abdominal drains, central venous catheters (CVC), and urinary catheters (UC) on post liver transplantation (LT) outcomes is not well elucidated. OBJECTIVES: To provide international expert panel recommendations and guidelines on time of drain and catheter removal as a part of an ERAS protocol to reduce the length of hospital stay and enhance recovery. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Papers considered were those reporting one or more outcomes of interest related to drainage and line removal in the setting of LT. POSPERO Protocol ID: CRD42021238349 RESULTS: On analyzing five relevant studies pertaining to drains in patients undergoing LT (four retrospectives and one prospective), the length of hospital and/or ICU stay was similar or shorter, and postoperative morbidity and mortality were lower in those without drains. No studies pertaining specifically to the time of removal of drains, CVC's, or UC's in LT were found. Studies in patients undergoing major abdominal surgery or hepatectomies recommend early removal of CVC and UC to reduce catheter-associated infections. CONCLUSIONS: Based more on expert recommendation, we propose that abdominal drains, if placed during LT, should be removed by postoperative day 5 after LT, based on quantity and fluid characteristics (Quality of Evidence; Low to Moderate | Grade of Recommendation; Strong). Larger studies are needed to more reliably determine indications for early drain and line removal in an ERAS protocol setting.

The role of preoperative psychosocial counseling on the improvement of the recipient compliance and speed of recovery after liver transplantation - A systematic review of the literature and expert panel recommendations.

BACKGROUND: Psychosocial disorders ranging from anxiety to severe psychiatric diseases and active alcohol/substance abuse are frequent in liver transplant candidates and potentially associated with worse post- transplant outcomes. Therefore, psychosocial evaluation is mandatory to optimize success after liver transplantation. However, how to carry out this evaluation, the type of intervention needed and its potential impact on patient outcome remain unclear. OBJECTIVES: To investigate whether psychosocial assessment may help in predicting risks of poor outcome; and to investigate whether psychosocial interventions may mitigate these risks and improve posttransplant outcomes, in particular compliance and speed of recovery. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. The protocol was registered on PROSPERO CRD42021238361. Main outcomes assessed were mortality, alcohol relapse, rejection, and medication compliance. RESULTS: Fifteen studies were analyzed including five observational comparative and ten observational noncomparative studies. Preoperative psychosocial evaluation of LT candidates was associated with higher concordance with the treatment plan (i.e., higher adherence to treatment and lower alcohol relapse) and lower rates of rejection. Psychosocial assessment tools were used in some studies to guide the evaluation, but their predictive ability remains debated, and they should not be used in isolation. Most of the interventions were studied in patients with alcohol related issues. In this context, support by specialized teams was associated with better posttransplant outcome, especially through a decrease in post-transplant alcohol relapse. CONCLUSIONS: Preoperative psychosocial assessment should be provided in order to detect patients at increased risk of poorer post-transplant outcome, in particular in terms of concordance to the treatment plan (Quality of Evidence; Low | Grade of Recommendation; Strong/For). The experts suggest that, when possible, provision of preoperative psychological assessment and concomitant interventions aimed at improving the concordance to treatment plans will positively impact the success of liver transplantation. (Quality of Evidence; Very Low | Grade of Recommendation; Strong/For].

The role of acute in-patient rehabilitation on short-term outcomes after liver transplantation: A systematic review of the literature and expert panel recommendations.

BACKGROUND: The indication and surgical complexity of orthotopic liver transplantation underscore the need for strategies to optimize the recovery for transplant recipients. We conducted a systematic review aimed at identifying, evaluating, and synthesizing the evidence examining the effect of in-patient rehabilitation for liver transplant recipients and provide related practice recommendations. METHODS: Health research databases were systematically reviewed for studies that included adults who received liver transplantation and participated in acute, post-transplant rehabilitation. Postoperative morbidity, mortality, length of hospital stay, length of intensive care unit stay, and other markers of surgical recovery were extracted. Practice recommendations are provided by an international panel using GRADE. RESULTS: Twelve studies were included in the review (including 3901 participants). Rehabilitation interventions varied widely in design and composition; however, details regarding intervention delivery were poorly described in general. The quality of evidence was rated as very low largely owing to "very serious" imprecision, poor reporting, and limited data from comparative studies. Overall, the studies suggest that in-patient rehabilitation for recipients of liver transplantation is safe, tolerable, and feasible, and may benefit functional outcomes. CONCLUSION: Two practice recommendations related to in-patient rehabilitation following LT were yielded from this review: (1) it is safe, tolerable, and feasible; and (2) it improves postoperative functional outcomes. Each of the recommendations are weak and supported by low quality of evidence. No recommendation could be made related to benefits or harms for clinical, physiological, and other outcomes. Adequately powered and high quality randomized controlled trials are urgently needed in this area.

When is the optimal time to discharge patients after liver transplantation with respect to short-term outcomes? A systematic review of the literature and expert panel recommendations.

BACKGROUND: Several factors associated with prolonged hospital stay have been described. A recent study demonstrated that hospital length of stay (LOS) is directly associated with an increased cost for liver transplantation (LT) and may be associated with greater mortality; however, the factors associated with post-LT mortality are also related to a prolonged hospital stay, that is, those factors are confounders. Thus, the actual impact of the length of post-LT hospital stay on both short-term and long-term patient and graft survival remains uncertain. OBJECTIVES: To identify the optimal time to discharge patients after LT with respect to short-term outcomes; readmission rate, 30-90-mortality and morbidity. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Initial search keywords for screening were as follows; ((discharge AND (time OR "time point" OR "time-point")) OR "length of hospital stay" OR "length of stay") AND ((liver OR hepatic) AND (transplant OR transplantation)). PROSPERO ID: CRD42021245598 RESULTS: The strength of recommendation was rated as Weak, and we did not identify the direction of recommendations regarding the optimal timing after LT concerning short-term outcomes, including "Readmission rate," six studies on 30- and/or 90-day mortality, and five studies on "30- and/or 90-day morbidity rate." CONCLUSIONS: Evidence is scarce to judge the optimal timing to discharge patients after LT with respect to short-term outcomes. In centers with robust outpatient follow-up, discharge can occur safely as early as post-transplant 6-8 days (Quality of Evidence [QOE]; Low | Grade of Recommendation; Weak).

The role of T-tubes and abdominal drains on short-term outcomes in liver transplantation - A systematic review of the literature and expert panel recommendations.

BACKGROUND: This systematic review and expert panel recommendation aims to answer the question regarding the routine use of T-tubes or abdominal drains to better manage complications and thereby improve outcomes after liver transplantation. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel to assess the potential risks and benefits of T-tubes and intra-abdominal drainage in liver transplantation (CRD42021243036). RESULTS: Of the 2996 screened records, 33 studies were included in the systematic review, of which 29 (six RCTs) assessed the use of T-tubes and four regarding surgical drains. Although some studies reported less strictures when using a T-tube, there was a trend toward more biliary complications with T-tubes, mainly related to biliary leakage. Due to the small number of studies, there was a paucity of evidence on the effect of abdominal drains with no clear benefit for or against the use of drainage. However, one study investigating the open vs. closed circuit drains found a significantly higher incidence of intra-abdominal infections when open-circuit drains were used. CONCLUSIONS: Due to the potential risk of biliary leakage and infections, the routine intraoperative insertion of T-tubes is not recommended (Level of Evidence moderate - very low; grade of recommendation strong). However, a T-tube can be considered in cases at risk for biliary stenosis. Due to the scant evidence on abdominal drainage, no change in clinical practice in individual centers is recommended. (Level of Evidence very low; weak recommendation).

What is the optimal anesthetic monitoring regarding immediate and short-term outcomes after liver transplantation?-A systematic review of the literature and expert panel recommendations.

BACKGROUND: Liver transplant centers vary in approach to intraoperative vascular accesses, monitoring of cardiac function and temperature management. Evidence is limited regarding impact of selected modalities on postoperative outcomes. OBJECTIVES: To review the literature and provide expert panel recommendations on optimal intraoperative arterial blood pressure (BP), central venous pressure (CVP), and vascular accesses, monitoring of cardiac function and intraoperative temperature management regarding immediate and short-term outcomes after orthotopic liver transplant (OLT). METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Recommendations made for: (1) Vascular accesses, arterial BP and CVP monitoring, (2) cardiac function monitoring, and (3) Intraoperative temperature management (CRD42021239908). RESULTS: Of 2619 articles screened 16 were included. Studies were small, retrospective, and observational. Vascular access studies demonstrated low rates of insertion complications. TEE studies demonstrated low rates of esophageal hemorrhage. One study found lower hospital-LOS and 30-day mortality in patients monitored with both PAC and TEE. Other monitoring studies were heterogenous in design and outcomes. Temperature studies showed increased blood transfusion and ventilation times in hypothermic groups. CONCLUSIONS: Recommendations were made for; routine arterial and CVP monitoring as a minimum standard of practice, consideration of discrepancy between peripheral and central arterial BP in patients with hemodynamic instability and high vasopressor requirements, and routine use of high flow cannulae while monitoring for extravasation and hematoma formation. Availability and expertise in PAC and/or TEE monitoring is strongly recommended particularly in hemodynamic instability, portopulmonary HT and/or cardiac dysfunction. TEE use is recommended as an acceptable risk in patients with treated esophageal varices and is an effective diagnostic tool for emergency cardiovascular collapse. Maintenance of intraoperative normothermia is strongly recommended.

Which cava anastomotic techniques are optimal regarding immediate and short-term outcomes after liver transplantation: A systematic review of the literature and expert panel recommendations.

BACKGROUND: It has long been debated whether cava anastomosis should be performed with the piggyback technique or cava replacement, with or without veno-venous bypass (VVB), with or without temporary portocaval shunt (PCS) in the setting of liver transplantation. OBJECTIVES: To identify whether different cava anastomotic techniques and other maneuvers benefit the recipient regarding short-term outcomes and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel (CRD42021240979). RESULTS: Of 3205 records screened, 307 publications underwent full-text assessment for eligibility and 47 were included in qualitative synthesis. Four studies were randomized control trials. Eighteen studies were comparative. The remaining 25 were single-center retrospective noncomparative studies. CONCLUSION: Based on existing data and expert opinion, the panel cannot recommend one cava reconstruction technique over another, rather the surgical approach should be based on surgeon preference and center dependent, with special consideration toward patient circumstances (Quality of evidence: Low | Grade of Recommendation: Strong). The panel recommends against routine use of vevo-venous bypass (Quality of evidence: Very Low | Grade of Recommendation: Strong) and against the routine use of temporary porto-caval shunt (Quality of evidence: Very Low | Grade of Recommendation: Strong).

Optimal anesthetic conduct regarding immediate and short-term outcomes after liver transplantation - Systematic review of the literature and expert panel recommendations.

BACKGROUND: In the era of enhanced recovery after surgery, there is significant discussion regarding the impact of intraoperative anesthetic management on short-term outcomes following liver transplantation (LT), with no clear consensus in the literature. OBJECTIVES: To identify whether or not intraoperative anesthetic management affects short-term outcomes after liver transplantation. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review following PRISMA guidelines was undertaken. The systematic review was registered on PROSPERO (CRD42021239758). An international expert panel made recommendations for clinical practice using the GRADE approach. RESULTS: After screening, 14 studies were eligible for inclusion in this systematic review. Six were prospective randomized clinical trials, three were prospective nonrandomized clinical trials, and five were retrospective studies. These manuscripts were reviewed to look at five questions regarding anesthetic care and its impact on short term outcomes following liver transplant. After review of the literature, the quality of evidence according to the following outcomes was as follows: intraoperative and postoperative morbidity and mortality (low), early allograft dysfunction (low), and hospital and ICU length of stay (moderate). CONCLUSIONS: For optimal short term outcomes after liver transplantation, the panel recommends the use of volatile anesthetics in preference to total intravenous anesthesia (TIVA) (Level of Evidence: Very low; Strength of Recommendation: Weak) and minimum alveolar concentration (MAC) versus bispectral index (BIS) for depth of anesthesia monitoring (Level of Evidence: Very low; Strength of Recommendation: Weak). Regarding ventilation and oxygenation, the panel recommends a restrictive oxygenation strategy targeting a PaO2 of 70-120 mmHg (10-14 kPa), a tidal volume of 6-8 ml/kg ideal body weight (IBW), administration of positive end expiratory pressure (PEEP) tailored to patient intraoperative physiology, and recruitment maneuvers. (Level of evidence: Very low; Strength of Recommendation: Strong). Finally, the panel recommends the routine use of antiemetic prophylaxis. (Level of evidence: low; Strength of Recommendation: Strong).

The optimal immunosuppression management to prevent early rejection after liver transplantation: A systematic review of the literature and expert panel recommendations.

BACKGROUND: The optimal immunosuppression protocol to prevent early acute cellular rejection (ACR) after liver transplantation (LT) avoiding prolonged hospitalization and early hospital readmission is undefined. OBJECTIVES: To identify the most suitable immunosuppression regimen for inclusion in ERAS programs in order to minimize early ACR after LT and to provide expert panel recommendations DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Studies from January 2000 onward focusing on early ACR were included. Rates of early renal dysfunction and infection were evaluated. CRD42021245586 RESULTS: Thirty-seven studies met inclusion criteria; 23 randomized controlled trials, 14 retrospective or prospective observational comparative or noncomparative studies. Several sources of biases which potentially confound conclusions were identified: heterogeneity in immunosuppression protocols, higher serum tacrolimus levels than currently used in clinical practice, differences in the definition of ACR. CONCLUSIONS: Tacrolimus is the standard immunosuppression after LT and can be used in combination with other drugs such as corticosteroids and MMF, and in association with anti-IL2 receptor antibody (IL2Ra) induction. (Quality of Evidence; Low | Grade of Recommendation; Strong). Low dose or delayed introduction of tacrolimus in association with corticosteroids and MMF and/or anti-IL2Ra induction can be used to reduce acute kidney injury. (Quality of Evidence; Low | Grade of Recommendation; Strong). Use of tacrolimus in association with corticosteroids and MMF and/or anti-IL2Ra induction does not lead to increased infection rates. (Quality of Evidence; Low | Grade of Recommendation; Weak).

What is the optimal antimicrobial prophylaxis to prevent postoperative infectious complications after liver transplantation? A systematic review of the literature and expert panel recommendations.

BACKGROUND: Antimicrobial prophylaxis is well-accepted in the liver transplant (LT) setting. Nevertheless, optimal regimens to prevent bacterial, viral, and fungal infections are not defined. OBJECTIVES: To identify the optimal antimicrobial prophylaxis to prevent post-LT bacterial, fungal, and cytomegalovirus (CMV) infections, to improve short-term outcomes, and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. PROSPERO ID: CRD42021244976. RESULTS: Of 1853 studies screened, 34 were included for this review. Bacterial, CMV, and fungal antimicrobial prophylaxis were evaluated separately. Pneumocystis jiroveccii pneumonia (PJP) antimicrobial prophylaxis was analyzed separately from other fungal infections. Overall, eight randomized controlled trials, 21 comparative studies, and five observational noncomparative studies were included. CONCLUSIONS: Antimicrobial prophylaxis is recommended to prevent bacterial, CMV, and fungal infection to improve outcomes after LT. Universal antibiotic prophylaxis is recommended to prevent postoperative bacterial infections. The choice of antibiotics should be individualized and length of therapy should not exceed 24 hours (Quality of Evidence; Low | Grade of Recommendation; Strong). Both universal prophylaxis and preemptive therapy are strongly recommended for CMV prevention following LT. The choice of one or the other strategy will depend on individual program resources and experiences, as well as donor and recipient serostatus. (Quality of Evidence; Low | Grade of Recommendation; Strong). Antifungal prophylaxis is strongly recommended for LT recipients at high risk of developing invasive fungal infections. The drug of choice remains controversial. (Quality of Evidence; High | Grade of Recommendation; Strong). PJP prophylaxis is strongly recommended. Length of prophylaxis remains controversial. (Quality of Evidence; Very Low | Grade of Recommendation; Strong).

Intraoperative transfusion management, antifibrinolytic therapy, coagulation monitoring and the impact on short-term outcomes after liver transplantation-A systematic review of the literature and expert panel recommendations.

BACKGROUND: Liver transplantation (LT) is frequently complicated by coagulopathy associated with end-stage liver disease (ESLD), that is, often multifactorial. OBJECTIVES: The objective of this systematic review was to identify evidence based intraoperative transfusion and coagulation management strategies that improve immediate and short-term outcomes after LT. METHODS: PRISMA-guidelines and GRADE-approach were followed. Three subquestions were formulated. (Q); Q1: transfusion management; Q2: antifibrinolytic therapy; and Q3: coagulation monitoring. RESULTS: Sixteen studies were included for Q1, six for Q2, and 10 for Q3. Q1: PRBC and platelet transfusions were associated with higher mortality. The use of prothrombin complex concentrate (PCC) and fibrinogen concentrate (FC) were not associated with reductions in intraoperative transfusion or increased thrombotic events. The use of cell salvage was not associated with hepatocellular carcinoma (HCC) recurrence or mortality. Cell salvage and transfusion education significantly decreased blood product transfusions. Q2: Epsilon-aminocaproic acid (EACA) and tranexamic acid (TXA) were not associated with decreased blood product transfusion, improvements in patient or graft survival, or increases in thrombotic events. Q3: Viscoelastic testing (VET) was associated with decreased allogeneic blood product transfusion compared to conventional coagulation tests (CCT) and is likely to be cost-effective. Coagulation management guided by VET may be associated with increases in FC and PCC use. CONCLUSION: Q1: A specific blood product transfusion practice is not recommended (QOE; low | Recommendation; weak). Cell salvage and educational interventions are recommended (QOE: low | Grade of Recommendation: moderate). Q2: The routine use of antifibrinolytics is not recommended (QOE; low | Recommendation; weak). Q3: The use of VET is recommended (QOE; low-moderate | Recommendation; strong).

Does machine perfusion improve immediate and short-term outcomes by enhancing graft function and recipient recovery after liver transplantation? A systematic review of the literature, meta-analysis and expert panel recommendations.

BACKGROUND: Recent evidence supports the use of machine perfusion technologies (MP) for marginal liver grafts. Their effect on enhanced recovery, however, remains uncertain. OBJECTIVES: To identify areas in which MP might contribute to an ERAS program and to provide expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review and meta-analysis following PRISMA guidelines and recommendations using the GRADE approach. CRD42021237713 RESULTS: Both hypothermic (HMP) and normothermic (NMP) machine perfusion demonstrated significant benefits in preventing postreperfusion syndrome (PRS) (HMP OR .33, .15-.75 CI; NMP OR .51, .29-.90 CI) and early allograft dysfunction (EAD) (HMP OR .51, .35-.75 CI; NMP OR .66, .45-.97 CI), while shortening LOS (HMP MD -3.9; NMP MD -12.41). Only NMP showed a significant decrease in the length of ICU stay (L-ICU) (MD -7.07, -8.76; -5.38 CI), while only HMP diminishes the likelihood of major complications. Normothermic regional perfusion (NRP) reduces EAD (OR .52, .38-.70 CI) and primary nonfunction (PNF) (OR .51, .27-.98 CI) without effect on L-ICU and LOS. CONCLUSIONS: The use of HMP decreases PRS and EAD, specifically for marginal grafts. This is supported by a shorter LOS and a lower rate of major postoperative complications (QOE; moderate | Recommendation; Strong). NMP reduces the incidence of PRS and EAD with associated shortening in L-ICU for both DBD and DCD grafts (QOE; moderate | Recommendation; High) This technology also shortens the length of hospital stay (QOE; low | Recommendation; Strong). NRP decreases the likelihood of EAD (QOE; moderate) and the risk of PNF (QOE; low) when compared to both DBD and SRR-DCD grafts preserved in SCS. (Recommendation; Strong).

The role of preoperative optimization of the nutritional status on the improvement of short-term outcomes after liver transplantation? A review of the literature and expert panel recommendations.

BACKGROUND: Malnutrition is a known risk factor for postoperative morbidity and mortality in patients awaiting liver transplantation (LT). Malnutrition is a potentially reversible risk factor, though there are no clear guidelines on the best mechanism for an improvement. It also remains unclear if preoperative nutritional interventions have benefits to post-transplant outcomes for transplant recipients. OBJECTIVES: Primary objective: To identify if preoperative optimization of nutritional status is associated with improved short-term outcomes after LT. SECONDARY OBJECTIVES: To determine if preoperative improvement of malnutrition improves short-term outcomes after LT, as well as if weight loss in obese patients affects short-term outcomes after LT. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. POSPERO Protocol ID: CRD42021237450 RESULTS: 3851 records were identified in searching the databases, 3843 records were excluded by not fulfilling eligibility criteria. Seven full-text articles were included for the final analysis of which three were randomized controlled trials, one was prospective observational studies, and three were retrospective observational studies. No appreciable difference in mortality, post-transplant complication rate was noted across the studies. Length of stay (LOS) was noted to be shorter in two observational studies of Vitamin D deficiency in liver transplant patients. CONCLUSIONS: We have made a weak recommendation supporting pre-transplant nutritional supplementation due to possible benefit in reducing LOS as well as the lack of harm (Quality of Evidence low | Grade of Recommendation; Weak). No effective conclusions were reached for the secondary objectives due to the conflicting evidence.

Optimal management of perioperative analgesia regarding immediate and short-term outcomes after liver transplantation - A systematic review, meta-analysis and expert panel recommendations.

BACKGROUND: Adequate pain control is essential for patients undergoing liver transplantation (LT). Multiple analgesic strategies have been implemented during the perioperative period. There is no consensus on the optimal perioperative analgesia management. OBJECTIVES: To provide recommendations, on the optimal perioperative analgesia management for LT. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review and meta-analysis following PRISMA guidelines and recommendations using GRADE. Studies describing outcomes, morbidity, mortality, pain scores, intensive care unit and hospital length of stay in patients that received different pain management techniques during and after LT were included (CRD42021243282). RESULTS: One thousand nine hundred ten articles were screened, but only two randomized controlled trials, one prospective and six retrospective studies were included. The opioid-avoidance protocols included, thoracic epidural analgesia (TEA), Transversus Abdominis Plane (TAP) block, as well as other non-opioid analgesics, resulted in improved short-term outcomes. Mortality was reduced in this group versus control cohorts (OR = 0.51; CI 0.14, 1.83; P = 0.350), Time to extubation, and intensive care unit LOS were shorter; pain scores after surgery were lower in opioid-avoidance group (percentage decrease, 35%, 12%, and 55%, respectively). However, hospital LOS was longer (percentage increase 8%). CONCLUSIONS: Opioid-avoidance analgesia management for LT results in improved short-term outcomes. (Quality of Evidence; Moderate to low | Grade of Recommendation; Weak). Medications such as acetaminophen(paracetamol), gabapentin, ketamine, tramadol and local anesthesia may be used instead of, or as adjuncts to opioids for postoperative analgesia. Overall evidence remains weak and more robust studies are required.

The role of early extubation on short-term outcomes after liver transplantation - A systematic review, meta-analysis and expert recommendations.

BACKGROUND: Early extubation in liver transplantation (LT) and its potential benefits such as reduction in pulmonary complications and enhanced postoperative recovery have been described. The extent of the effect of early extubation on short-term outcomes after LT across the published literature is to the best of our knowledge unknown. OBJECTIVES: The objective of this systematic review and meta-analysis was to determine whether early extubation improves immediate and short-term outcomes after LT and to provide expert recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review and meta-analysis on short-term outcomes after early extubation in LT was performed (CRD42021241402), following PRISMA guidelines and quality of evidence (QOE) and recommendations grading using the GRADE approach, derived from an international experts panel. Endpoints were reintubation rates, pulmonary and other complications/organ dysfunction, intensive care unit (ICU) and hospital length of stay (LOS). RESULTS: Of 831 screened articles, 20 observational studies with a total of 3573 patients addressing early extubation protocols were included, of which 12 studies compared results after early versus deferred extubation. Reintubation and pulmonary complication rates were lower in the early versus deferred extubation groups (OR 0.29, CI 0.22-0.39; OR 0.17, CI 0.09-0.33, respectively). ICU and hospital LOS were shorter in eight out of eight and seven out of eight comparative studies, respectively. CONCLUSIONS: Early extubation after LT is associated with improved short-term outcomes after LT and should be performed in the majority of patients (QOE; Moderate to low | Grade of Recommendation; Strong). Randomized controlled trials using standardized definitions of early extubation and short-term outcomes are needed to demonstrate causality, validate and allow comparability of the results.

The role of graft to recipient weight ratio on enhanced recovery of the recipient after living donor liver transplantation - A systematic review of the literature and expert panel recommendations.

BACKGROUND: There continues to be debate about the lower limit of graft-to-recipient weight ratio (GRWR) for living donor liver transplant (LDLT). OBJECTIVES: To identify the lower limit of GRWR compatible with enhanced recovery after living donor liver transplant and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Studies assessing how GRWR affects recipient outcomes such as small for size syndrome, other complications, patient and graft survival, and length of stay were included. PROTOCOL REGISTRATION: CRD42021260794. RESULTS: Twenty articles were included in the qualitative synthesis, and all were retrospective observational studies. There was heterogeneity in the definition of study cohorts and key outcome measures such as small-for-size syndrome. Most studies lacked risk adjustment given limited single-center sample size. GRWR of ≥ .8% is associated with enhanced recovery. Recipients of grafts with GRWR < .8%, however, were found to have similar outcomes as those with ≥ .8% when appropriate consideration is made for portal flow modulation and recipient illness severity. CONCLUSIONS: GRWR ≥ .8% is often compatible with enhanced recovery, but grafts < .8% can be used in selected LDLT recipients with optimal donor-recipient selection, surgical technique, and perioperative management (Quality of Evidence; Low | Grade of Recommendation; Strong).

Optimal surgical workup to ensure safe recovery of the donor after living liver donation - A systematic review of the literature and expert panel recommendations.

BACKGROUND: The essential premise of living donor liver transplantation is the assurance that the donors will have a complication-free perioperative course and a prompt recovery. Selection of appropriate donors is the first step to support this premise and is based on tests that constitute the donor workup. The exclusion of liver pathologies and assessment of liver anatomy and volume in the donor candidate are the most important elements in the selection of the appropriate candidate. OBJECTIVE: To determine whether there is evidence to define an optimal donor surgical workup that would improve short-term outcomes of the donor after living liver donation. DATA SOURCES: Ovid Medline, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. RESULTS: Although a liver biopsy remains the only method to exactly determine the percentage and type of steatosis and to detect other liver pathologies, its routine use is not supported. Both magnetic resonance imaging (MRI) and computed tomography (CT) appear to be adequate for quantifying liver volume; the preference for one or the other is often based on center expertise. MRI is clearly a better technique to assess biliary anatomy, although aberrant biliary anatomy may not be clearly detected. MRI is also more accurate than CT in determining low grades of steatosis. CT angiography is the imaging test of choice to assess the vascular anatomy. There is no evidence of the need for catheter angiography in the modern evaluation of a living liver donor. CONCLUSIONS: A donor liver biopsy is indicated if abnormalities are present in serological or imaging tests. Both MRI and CT imaging appear to be adequate methodologies. The routine use of catheter angiography is not supported in view of the adequacy of CT angiography in delineating liver vascular anatomy. No imaging modality available to quantify liver volume is superior to another. Biliary anatomy is better defined with MRI, although poor definition can be expected, particularly for abnormal ducts.

Which preoperative assessment modalities best identify patients who are suitable for enhanced recovery after liver transplantation? A systematic review of the literature and expert panel recommendations.

BACKGROUND: To implement Enhanced Recovery After Surgery (ERAS) protocols for liver transplant (LT) candidates, it is essential to identify tools that can help risk stratify patients by their risk of early adverse post-LT outcomes. OBJECTIVE: We aimed to identify pre-LT tools that assess functional capacity, frailty, and muscle mass that can best risk stratify patients by their risk of adverse post-LT outcomes. METHODS: We first conducted a systematic review following PRISMA guidelines, expert panel review and recommendations using the GRADE approach (PROSPERO ID CRD42021237434). After confirming there are no studies evaluating assessment modalities for ERAS protocols for LT recipients specifically, the approach of the review focused on pre-LT modalities that identify LT recipients at higher risk of worse early post-LT outcomes (≤90 days), considering that this is particularly pertinent when evaluating candidates for ERAS. RESULTS: Twenty-two studies were included in the review, encompassing three different types of pre-LT modalities: evaluation of physical function (including frailty and general physical scores like the Karnofsky Performance Status (KPS), assessment of cardiopulmonary capacity, and estimation of muscle mass and composition. The majority of studies evaluated frailty assessment and muscle mass. Most studies, except for liver frailty index (LFI), were retrospective and single-center. All assessment modalities could identify, in different grade, LT recipients with higher risk of early post-LT mortality, length of stay or postoperative complications. CONCLUSIONS: We identified four pre-LT assessment tools that could be used to identify patients who are suitable for ERAS protocols: (1) KPS (quality of evidence moderate, grade of recommendation strong); (2) LFI (quality of evidence moderate, grade of recommendation strong); (3) abdominal muscle mass by CT (quality of evidence moderate, grade of recommendation strong); and (4) cardiopulmonary exercise testing (CPET) (quality of evidence moderate, grade of recommendation weak). We recommend that selection of the appropriate tool depends on the specific clinical setting and available resources to administer the tool, and that use of a tool be incorporated into the routine preoperative assessment when considering implementation of ERAS protocols for LT.