Anhepatic Phase Research Articles

Approaches to reconstruction of inferior vena cava by ex vivo liver resection and autotransplantation in 114 patients with hepatic alveolar echinococcosis

BACKGROUNDHepatic alveolar echinococcosis (AE) is most commonly found in retrohepatic inferior vena cava (RHIVC). Ex vivo liver resection and autotransplantation (ELRA) can better realize the radical resection of end-stage hepatic AE with severely compromised hepatocaval confluences, and reconstruction of the affected vessels. Currently, there is a scarcity of information regarding RHIVC reconstruction in ELRA.AIMTo propose reasonable RHICV reconstruction strategies for ex vivo liver resection and autotransplantation.METHODSWe retrospectively summarized the clinical data of 114 patients diagnosed with hepatic AE who treated by ELRA in our department. A total of 114 patients were divided into three groups according to the different reconstruction methods of RHIVC: Group A with original RHIVC being repaired and reconstructed (n = 64), group B with RHIVC being replaced (n = 43), and group C with RHIVC being resected without reconstruction (n = 7). The clinical data of patients, including the operation time, anhepatic phase, intraoperative blood loss, complications and postoperative hospital stay, were analyzed and the patients were routinely followed up. The normally distributed continuous variables were expressed as means ± SD, whereas the abnormally distributed ones were expressed as median and analyzed by analysis of variance. Survival curve was plotted by the Kaplan-Meier method.RESULTSAll patients were routinely followed up for a median duration of 52 (range, 12-125) mo. The 30 d mortality rate was 7.0% (8/114) and 7 patients died within 90 d. Among all subjects, the inferior vena cava (IVC)-related complication rates were 17.5% (11/63) in group A and 16.3% (7/43) in group B. IVC stenosis was found in 12 patients (10.5%), whereas thrombus was formed in 6 patients (5.3%). Twenty-two patients had grade III or higher complications, with the complication rates being 17.2%, 16.3%, and 57.1% in the three groups. The average postoperative hospital stay in the three groups was 32.3 ± 19.8, 26.7 ± 18.2, and 51.3 ± 29.4 d (P = 0.03), respectively.CONCLUSIONELRA can be considered a safe and feasible option for end-stage hepatic AE patients with RHIVC infiltration. The RHIVC reconstruction methods should be selected appropriately depending on the defect degree of AE lesions in IVC lumen. The RHIVC resection without any reconstruction method should be considered with caution.

Porcine Liver Transplantation Without Veno-venous Bypass As an Extended Criteria Donor Model.

Liver transplantation is regarded as the gold standard for the treatment of a variety of fatal hepatic diseases. However, unsolved issues of chronic graft failure, ongoing organ donor shortages, and the increased use of marginal grafts call for the improvement of current concepts, such as the implementation of organ machine perfusion. In order to evaluate new methods of graft reconditioning and modulation, translational models are required. With respect to anatomical and physiological similarities to humans and recent progress in the field of xenotransplantation, pigs have become the main large animal species used in transplantation models. After the initial introduction of a porcine orthotopic liver transplant model by Garnier et al. in 1965, several modifications have been published over the past 60 years. Due to specifies-specific anatomical traits, a veno-venous bypass during the anhepatic phase is regarded as a necessity to reduce intestinal congestion and ischemia resulting in hemodynamic instability and perioperative mortality. However, the implementation of a bypass increases the technical and logistical complexity of the procedure. Furthermore, associated complications such as air embolism, hemorrhage, and the need for a simultaneous splenectomy have been reported previously. In this protocol, we describe a model of porcine orthotopic liver transplantation without the use of a veno-venous bypass. The engraftment of donor livers after static cold storage of 20 h - simulating extended criteria donor conditions - demonstrates that this simplified approach can be performed without significant hemodynamic alterations or intraoperative mortality and with regular uptake of liver function (as defined by bile production and liver-specific CYP1A2 metabolism). The success of this approach is ensured by an optimized surgical technique and a sophisticated anesthesiologic volume and vasopressor management. This model should be of special interest for workgroups focusing on the immediate postoperative course, ischemia-reperfusion injury, associated immunological mechanisms, and the reconditioning of extended criteria donor organs.

An Innovation in the Technique of Recipient Hepatectomy in Living Donor Liver Transplantation.

Recipient hepatectomy is a challenging surgical procedure. Coagulopathy, multiple collaterals, and dense adhesions secondary to previous spontaneous bacterial peritonitis in cirrhotics are the major contributing factors. However, the appropriate recipient hepatectomy technique can limit the massive blood loss and minimize the operative time. The hepatoduodenal dissection has a key role in recipient hepatectomy. The hilar structures of partial graft in live donor liver transplantation (LDLT) usually have a short length and a small caliber. The concerning task in LDLT recipient hepatectomy is to preserve the integrity, quality, and adequacy of hilar structures for successful implantation. The high hilar dissection technique is usually practiced for getting the adequate length of hilar structures. However, the problems with high hilar dissection inducted the authors to tailor the technique over time. In this report, a modified technique of recipient hepatectomy characterised by the artery-first approach is described. This technique is good in terms of preventing arterial dissection and minimising the anhepatic phase. Key Words: Recipient hepatectomy, Hepatoduodenal dissection, Liver transplantation, Technique.

Detection and quantification of perioperative heparin-like effects by rotational thromboelastometry in living-donor liver transplant recipients: A prospective observational study.

Heparin-like effects (HLEs) can affect hemostasis during liver transplantation. The aim of this study was to assess the perioperative incidence and severity of HLE with rotational thromboelastometry (ROTEM) and activated partial thromboplastin time (aPTT). ROTEM and aPTT were measured intraoperatively and on postoperative days (POD) 1, 3, and 7. HLE was identified if ROTEM INTEM/HEPTEM CT-ratio was >1.25 and severe forms of HLE when ratio was ≥2. Based on aPTT, HLE was defined when aPTT ratio was >1.25 (patient aPTT/control aPTT). Thirty-eight recipients were included. Variable degrees of HLE were detected by aPTT-ratio and INTEM/HEPTEM CT ratio. No significant correlation existed between both ratios. Based on INTEM/HEPTEM CT ratio, HLE was detected in 7/38 during anhepatic phase, 19/38 post-reperfusion, 10/38 on POD1, 4/38 on POD3, and 0/38 on POD7. Four cases of severe HLE were identified by INTEM/HEPTEM CT ratio only in the anhepatic phase. Postoperative infusion of unfractionated heparin led to mild-moderate HLE on POD1 and 3 as evident by both tests. Red blood cell and plasma transfusion were higher with severe HLE (1350 ± 191 ml and 3558 ± 1407 ml). Composite adverse outcome of any complication or death within 3 months for patients without HLE, mild-moderate HLE, and severe HLE as detected by ROTEM was 27.8%, 42.9%, and 66.7%, respectively. INTEM/HEPTEM CT ratio was able to detect and quantify HLE as aPTT ratio. The ability of the INTEM/HEPTEM CT ratio to identify severe HLE earlier in the anhepatic phase needs to be studied in a larger population. HLE is self-limiting, but when identified in a severe form, it is associated with worse outcome.

Modified cavocavostomy technique for deceased donor liver transplantation

Rationale. The refinement of liver transplantation technique, the development and implementation of new surgical technologies into clinical practice, including those for inferior vena cava reconstruction, are important for the improvement of surgery outcomes.The study purposes were to present our own modification of cavocavostomy and options for its technical implementation in deceased donor liver transplantation, as well as to study the clinical effects and the impact of new surgical technique on the outcomes.Material and methods. A retrospective, single-centre study included the data from 109 consecutive deceased donor liver transplantations performed between 2012 and 2021. In 106 procedures, inferior vena cava reconstruction was performed either according to the classic technique (group 1, n=23, 22%), or using our own modification of cavocavostomy (group 2, n=83, 78%). To assess the clinical efficacy and safety of the new surgical technique, we compared the characteristics of donors and recipients, intraoperative parameters, features of early postoperative course, incidence of surgical complications, initial function, immediate and long-term graft survival. Three piggyback procedures were not included in the comparative analysis.Results. Two groups were generally comparable in terms of the characteristics of donors and recipients, however, the classic inferior vena cava was significantly more often used during transplants for unresectable parasitic liver lesions (17% vs. 1%, p=0.008) and retransplantations (30% vs. 5%, p=0.002). There were no statistically significant differences in the main intraoperative parameters between groups 1 and 2. The duration of transplantations was 8.0 h (interquartile range: 6.5–8.5 h) and 7.0 h (interquartile range: 6.0–8.0 h), p=0.112; anhepatic phase lasted 70 min (interquartile range: 60–75 min) and 70 min (interquartile range: 59–90 min), p=0.386; warm ischemia time was 45 min (interquartile range: 38–52 min) and 45 min (interquartile range: 38–50 min), p=0.690; inferior vena cava was clamped for 47 min (interquartile range: 40–55 min) and 50 min (interquartile range: 40–55 min), p=0.532. The volumes of intraoperatively transfused blood components were, respectively: packed red cells 630 ml (interquartile range: 0–1280 ml) and 600 ml (interquartile range: 0–910 ml), p=0.262; blood reinfusion 770 ml (interquartile range: 360–1200 ml) and 700 ml (interquartile range: 0–1200 ml), p=0.370; fresh frozen plasma 2670 ml (interquartile range: 2200 and 3200 ml) and 2240 ml (interquartile range: 1880–2900 ml), p=0.087.When using classic caval reconstruction technique, the proportion of grafts with early dysfunction was higher: 44% vs. 17% (p=0.011), due to the higher rate of retransplantations in this group. The incidence of acute kidney injury (by RIFLE > I) was 35% and 19% (p=0.158), the need for renal replacement therapy was 22% and 15% (p=0.520) in group 1 and group 2, respectively. The total incidence of surgical complications in the early postoperative period was 30% and 16%, p=0.110.Conclusions. The proposed technique of cavocavostomy can be considered as a priority method for caval reconstruction during deceased donor liver transplantation, with the exception of specific indications for the use of the classic technique (retransplantation, involvement of the inferior vena cava wall in a parasitic process or presentation of a tumor node to it, as well as in cases of widespread adhesive process in the abdominal cavity, hypertrophy of the 1 segment of the native liver, the presence and location of TIPS, thinning of the wall of the retrohepatic inferior vena cava, the risk of graft compression with its large size).The choice of the cavocavostomy variant should be carried out taking into account the size ratio of the graft to the recipient's right subdiaphragmatic space, and the topography features of the recipient's hepatic veins.

A look into hemostatic characteristics during pediatric liver transplantation using the thromboelastometry (ROTEM® ) test.

There is a paucity of evidence about the coagulation profile regarding the complexity of children undergoing liver transplantation (LT). This study aimed to investigate intraoperative hemostatic changes during pediatric LT according to the etiology for LT and examine the ability of rotational thromboelastometry (ROTEM® , TEM International GmbH, Munich, Germany) as a point-of-care monitoring method. We evaluated 106 patients aged 3months to 17years undergoing LT for acute liver failure (ALF) and chronic liver disease, which consists of patients with cholestatic disease, metabolic/genetic disease, and cancer. A total of 731 ROTEM® measurements, including 301 ellagic acid to initiate clotting via the intrinsic pathway, 172 tissue factor to initiate the extrinsic clotting cascade (EXTEM), and 258 cytochalasin D to inhibit platelet activity reflecting fibrinogen (FIBTEM), were analyzed at predetermined time points (the preanhepatic, anhepatic, and postreperfusion phases). We simultaneously conducted conventional coagulation tests. In children with ALF, preanhepatic measurements of conventional coagulation tests and ROTEM® showed a more hypocoagulable state than other diseases. During LT, the coagulation profile was deranged, with a prolonged clotting time and reduced clot firmness, changes that were more profound in the cholestatic disease group. Maximum clot firmness (MCF) on EXTEM and FIBTEM were well correlated with the platelet count and fibrinogen concentration (r=0.830, p<0.001 and r=0.739, p<0.001, respectively). On the EXTEM, MCF with 30mm predicted a platelet count <30,000/mm3 (area under the curve, 0.985), and 6mm predicted a fibrinogen concentration <100mg/dl on the FIBTEM (area under the curve, 0.876). However, the activated partial thromboplastin time and prothrombin time were significant but only weakly correlated with the clotting time on the ROTEM® . In children undergoing LT, coagulation profiles depend on the etiology for LT. During LT, ROTEM® parameters could help detect thrombocytopenia and hypofibrinogenemia and guide transfusion therapy as a point-of-care monitoring method.

One Step at a Time: A Pediatric Case of Primary Two Staged Liver Transplantation in a Child with ESLD

Toxic liver syndrome is a rare condition with multiorgan failure in end-stage liver disease (ESLD), and a two-stage LT following hepatectomy with a prolonged anhepatic phase is an accepted approach to bridge to transplant. This primary approach has not been described for toxic liver syndrome in children with ESLD. We report a 6-year-old boy who developed toxic liver syndrome with multiorgan failure while awaiting LT for ESLD from biliary atresia and failed Kasai at the age of 2 years. Deemed too sick to transplant, he underwent full hepatectomy and portocaval shunt placement. The child was then transplanted hemodynamically stable after an anhepatic phase of 10 h and 30 min. Although his initial graft showed primary liver dysfunction and he needed re-transplantation after 14 days, he was able to leave the hospital 4 months following 2nd LT and is well with a fully working graft 5 years later. Primary two stage LT is feasible in children in dire situations.

Correlation of Cardiac Output by Arterial Contour-Derived Cardiac Output Monitor Versus Pulmonary Artery Catheter in Liver Transplant: Experience at an Indian Center

Objective:Arterial pulse-derived cardiac output monitors are routinely employed to guide hemodynamic management during liver transplant surgery. In this study, we sought to assess the reliability by evaluating the agreement of the cardiac output measured by the FloTrac Vigileo versus pulmonary artery catheter (continuous cardiac output) at specified times during liver transplant.Methods:Liver transplant database with cardiac output values measured by FloTrac Vigileo and continuous cardiac output was analyzed retrospectively at a tertiary care hospital. Data were compared at T0: baseline, T1: 1 hour in dissection phase, T2: anhepatic phase, T3: portosystemic shunt, T4: reperfusion, T5: 1 hour after reperfusion, and T6: skin closure. Statistical analysis was done using Bland–Altman analysis and percentage error (<30%) to assess the agreement between cardiac output measured by 2 techniques, Lin’s concordance correlation coefficient for quantifying the agreement and 4-quadrant plots to compare the trends of cardiac output.Results:Bland–Altman analysis showed mean cardiac output ± standard deviation L min-1 (95% CI) at T0: 0.2 ± 2.09 (−3.9 to 4.3), T1: 0.53 ± 3.0 (−5.4 to 6.4), T2: 0.47 ± 2.1(−3.7 to 4.6), T3: 0.31 ± 1.9 (−3.4 to 4.0), T4: 0.44 ± 2.15 (−3.8 to 4.7), T 5:0.69 ± 1.9. (−2.9 to 4.3), and at T6: 0.43 ± 2.25 (−4.0 to 4.8). Percentage error was 44%-72% and concordance correlation coefficient was poor (<0.65) at all points.Conclusions:There is poor agreement between the cardiac output measured by FloTrac and pulmonary artery catheter among liver transplant recipients. The need for superior hemodynamic monitoring is mandated in liver transplant.

Changes in the Serum Fatty Acid Profile After Anhepatic Phase of Orthotopic Liver Transplantation Procedure.

During orthotopic liver transplantation (OLT), the patients’ body remains deprived of this organ for some time, which could cause critical changes in the levels of various metabolites in the circulation, including fatty acids. Thus, the aim of this study was to determine whether the liver transplantation procedure leads to significant changes in the FA profile in serum lipids after the anhepatic phase. Our gas chromatography–mass spectrometry analysis revealed that after transplantation, serum levels of myristic and palmitic acids significantly decreased, whereas serum levels of very long-chain FAs containing 20 or more carbons in their chains were increased. These results indicate that the anhepatic phase during liver transplantation produces significant changes in serum fatty acid levels, and emphasizes the role of the liver in the metabolism of very long-chain fatty acids.

Hepatitis B immunoglobulin prophylaxis for de novo hepatitis B infection in liver transplantation: a 30-year experience

BackgroundDonors positive for hepatitis B core antibody (HBcAb) are an important source of organs in hepatitis B virus (HBV) endemic areas despite the risk of occult infection. We analyzed the long-term outcomes of hepatitis B immunoglobulin in de novo HBV prevention following liver transplantation (LT) using HBcAb-positive grafts.MethodsThe prospectively collected data from 2,201 recipients at Seoul National University Hospital (SNUH) and Seoul National University Boramae Medical Center between 1988 and 2018 were retrospectively reviewed. A total of 1,458 patients were enrolled. Of the 1,458, 478 (32.8%) grafts were core-positive, 152 (10.4%) of which belonged to HBV surface antigen-negative recipients. During the anhepatic phase, hepatitis B immunoglobulin 4,000 IU was administered intravenously and daily until postoperative day 3.ResultsThe 152 patients with hepatitis B surface antigen-negative received HBcAb-positive graft. De novo HBV developed in 21 (13.8%) of these recipients. De novo HBV occurred in 1, 11, 0, and 9 of the 4 HBcAb- and hepatitis b surface antibody (anti-HB)-negative, 49 HBcAb-negative and anti-HB-positive, 1 HBcAb-positive and anti-HB-negative, and 98 HBcAb- and anti-HB-positive recipients, respectively. Patients with higher Model for End-stage Liver Disease (MELD) score (23.8±8.7 vs. 19.5±9.2) or HBcAb-negative recipients (22.6% vs. 9.1%) had a higher risk of de novo infection. The median follow-up and serum HBV surface antigen-positivity detection time was 69 and 18 months, respectively. The median HBV surface antibody titer was 65.0 IU/L at de novo infection. Nineteen patients of 21 were treated with nucleoside analogs (NAs), and seven of 19 achieved seroconversion. No patient died of de novo HBV infection.ConclusionsWith close monitoring of viral serum markers and appropriate initiation of NAs, de novo HBV infection can be prevented and treated appropriately with the hepatitis B immunoglobulin monoprophylaxis protocol.

The Requirement of Isoflurane and Remifentanil During Liver Transplantation Using Bispectral Index and Surgical Pleth Index: An Observational Study

During liver transplantation (LT), patients and surgical factors potentially influence the pharmacokinetics of the anesthetic agents. The aim of this study was to investigate the requirement of isoflurane and remifentanil according to severity of liver disease during LT under balanced anesthesia. We enrolled 44 patients undergoing LT. Anesthetic depth was maintained within the bispectral index score of 40 to 60 and Surgical Pleth Index of 20 to 60. Patients were divided into 2 groups according to their median Model for End-Stage Liver Disease (MELD) score: low MELD group and high MELD group. We compared end-tidal inhaled anesthetics and remifentanil consumption. Patients were divided into 2 groups according to median value of MELD score: MELD score <16 (low MELD group; n=20) or MELD ≥16 (high MELD group; n=20). There was no significant difference between the 2 groups in end-tidal concentration of isoflurane during 3 phases. However, the remifentanil requirement was lower in the high MELD group during the dissection and anhepatic phases (mean (SD), 0.105 (0.067) vs 0.064 (0.055) µg/kg/min; P=.037, and 0.167 (0.096) vs 0.108 (0.079) µg/kg/min; P=.039, respectively; low MELD group vs high MELD group) with no significant difference during the neohepatic phase. The severity of liver dysfunction based on MELD score affected the intraoperative remifentanil requirement during LT. Patients with cirrhosis are required to use analgesics appropriate to their individual patient characteristics in clinical practice.

The vexing triad of obesity, alcohol, and coagulopathy predicts the need for multiple operations in liver transplantation

IntroductionOne in four liver transplants (LT) require return to the operating room(R-OR) within 48 h of surgery. We hypothesize that donor, recipient, and intraoperative factors will predict R-OR. MethodsLT recipients were enrolled in an observational study to measure coagulation with thrombelastography (TEG) were assessed with transplant recipient and donor variables for risk of R-OR. Results160 recipients with a median age of 55 years and a MELD-Na of 22 were analyzed. R-OR occurred in 22%. Recipient BMI (p = 0.006), donor heavy alcohol use (p = 0.017), TEG MA (p = 0.013) during the anhepatic phase of surgery, TEG MA at anhepatic and 30-min after reperfusion (p < 0.05), and red blood cell transfusions (p < 0.001) were associated with R-OR. ConclusionThe vexing triad of recipient obesity, heavy donor alcohol use, and low TEG MA were associated with a high rate of R-OR. Strategies to reduce this sub-optimal combination of risk factors could reduce the frequency of unplanned re-operations.

Perioperative kidney injury in liver transplantation: a prospective study with renal histology and measured glomerular filtration rates

Background Acute kidney injury (AKI) is frequent after liver transplantation (LT), with impact on graft function, morbidity and mortality. Although multifactorial, the pathophysiology of perioperative kidney injury remains unclear. Our aims were to analyze the frequency, evolution and risk factors for kidney impairment during the peri- and early post-operative period. Methods In a prospective, single-center study of 27 adult patients undergoing first single-organ LT, we analyzed measured glomerular filtration rate (mGFR) pre-transplant, at post-operative day (POD) 10, and at 1, 3, 12 and 36 months. Kidney and liver graft biopsies were performed during LT. Results A median mGFR decline of 45% was detected from pre-transplant to POD 10, correlating strongly with the mGFR evolution from baseline to 12 months (rs = 0.80, p<.001) and baseline to 36 months (rs = 0.82, p<.001). AKI occurred in 59% of recipients within 48 h of LT, notably before the introduction of calcineurin inhibitors on POD 3. AKI was strongly associated with mGFR at 12 and 36 months. Kidney and liver graft biopsies showed only minor histological changes. Donor and recipient body mass index, recipient age, model of end-stage liver disease score, diagnosis of hepatitis C, donor cause of death, as well as bleeding, transfusions and duration of the anhepatic phase correlated with early kidney dysfunction. Conclusion The greatest decline in mGFR was evident within 10 days and AKI within hours of LT, irrespective of baseline mGFR and before introduction of calcineurin inhibitors. Very early post-LT kidney injury has substantial consequences for long-term kidney function.

Regional anticoagulation magnetic artificial blood vessels constructed by heparin-PLCL core-shell nanofibers for rapid deployment of veno-venous bypass.

Veno-venous bypass (VVB) is necessary for maintaining hemodynamic and internal environment stabilities in complex liver surgeries. However, the current VVB strategies require systematic anticoagulation and are time-consuming, leading to unexpected complications. This study aims to overcome these limitations by using a novel magnetic artificial blood vessel constructed with heparin-PLCL core-shell nanofibers. Coaxial electrospinning was used to fabricate core-shell nanofibers with heparin encapsulated into the core layer. The microstructure, physical and chemical properties, hemocompatibility, and heparin release behavior were characterized. The regional anticoagulation magnetic artificial vessel was constructed with these nanofibers and used to perform VVB in a rat liver transplantation model for in vivo evaluation. The core-shell nanofibers appeared smooth and uniform without apparent defects. Fluorescence and TEM images indicated that heparin was successfully encapsulated into the core layer. In addition, the in vitro heparin release test presented a two-phase release profile, burst release at day 1 and sustained release from days 2 to 14, which resulted in better hemocompatibility. The VVB could be rapidly deployed in 3.65 ± 0.83 min by the magnetic artificial vessel without systemic anticoagulation. Moreover, the novel device could reduce portal pressure and abdominal organ congestion, protect intestinal function, and increase the survival rate of liver transplantation with a long anhepatic phase from 0 to 65%. In summary, VVB can be rapidly deployed using regional anticoagulation magnetic artificial blood vessels without systemic anticoagulation, which is promising for improving patient outcomes after complex liver surgery.

Magnetic-assisted laparoscopic liver transplantation in swine

BackgroundAlthough laparoscopic technology has achieved rapid development in the surgical field, it has not been applied to liver transplantation, primarily because of difficulties associated with laparoscopic vascular anastomosis. In this study, we introduced a new magnetic-assisted vascular anastomosis technique and explored its application in laparoscopic liver transplantation in pigs. MethodsTwo sets of magnetic vascular anastomosis rings (MVARs) with different diameters were developed. One set was used for anastomosis of the suprahepatic vena cava (SHVC) and the other set was used for anastomosis of the infrahepatic vena cava (IHVC) and portal vein (PV). Six laparoscopic orthotopic liver transplantations were performed in pigs. Donor liver was obtained via open surgery. Hepatectomy was performed in the recipients through laparoscopic surgery. Anastomosis of the SHVC was performed using hand-assisted magnetic anastomosis, and the anastomosis of the IHVC and PV was performed by magnetic anastomosis with or without hand assistance. ResultsLiver transplants were successfully performed in five of the six cases. Postoperative ultrasonographic examination showed that the portal inflow was smooth. However, PV bending and blood flow obstruction occurred in one case because the MVARs were attached to each other. The durations of loading of MVAR in the laparoscope group and manual assistance group for IHVC and PV were 13 ± 5 vs. 5 ± 1 min (P < 0.01) and 10 ± 2 vs. 4 ± 1 min (P < 0.05), respectively. The durations of MVAR anastomosis in the laparoscope group and manual assistance group for IHVC and PV were 5 ± 1 vs. 1 ± 1 min (P < 0.01), and 5 ± 1 vs. 1 ± 1 min (P < 0.01), respectively. The anhepatic phase was 43 ± 4 min in the laparoscope group and 23 ± 2 min in the manual assistance group (P < 0.01). ConclusionsOur study showed that magnetic-assisted laparoscopic liver transplantation can be successfully carried out in pigs.

Intraoperative lactic acid concentration during liver transplantation and cutoff values to predict early mortality: a retrospective analysis of 3,338 cases

BackgroundWe aimed to explore the distribution of intraoperative lactic acid (LA) level during liver transplantation (LT) and determine the optimal cutoff values to predict post-LT 30-day and 90-day mortality.MethodsIntraoperative LA data from 3,338 patients were collected between 2008 to 2019 and all-cause mortalities within 30 and 90 days were retrospectively reviewed. Of the three LA levels measured during preanhepatic, anhepatic, and neohepatic phase of LT, the peak LA level was selected to explore the distribution and predict early post-LT mortality. To determine the best cutoff values of LA, we used a classification and regression tree algorithm and maximally selected rank statistics with the smallest P value.ResultsThe median intraoperative LA level was 4.4 mmol/L (range: 0.5–34.7, interquartile range: 3.0–6.2 mmol/L). Of the 3,338 patients, 1,884 (56.4%) had LA levels > 4.0 mmol/L and 188 (5.6%) had LA levels > 10 mmol/L. Patients with LA levels > 16.7 mmol/L and 13.5–16.7 mmol/L showed significantly higher 30-day mortality rates of 58.3% and 21.2%, respectively. For the prediction of the 90-day mortality, 8.4 mmol/L of intraoperative LA was the best cutoff value.ConclusionsApproximately 6% of the LT recipients showed intraoperative hyperlactatemia of > 10 mmol/L during LT, and those with LA > 8.4 mmol/L were associated with significantly higher early post-LT mortality.

New onset nonischemic cardiomyopathy post liver transplantation.

A new onset acute heart failure (HF) with a sudden drop in the left ventricular ejection fraction (LVEF) post orthotopic liver transplant (LT) is a rare but a potentially fatal complication. Because in most of the cases there is no evidence of coronary thrombosis, it can be classified as nonischemic cardiomyopathy. More specifically, clinical presentation of this syndrome shares many features with stress-induced or takotsubo cardiomyopathy. The known factors that predispose these patients to acute HF during or shortly after LT include cirrhotic cardiomyopathy, rapid hemodynamic changes during LT surgery, and the large concentrations of catecholamines, either administered or released endogenously during surgery. The hemodynamic changes during surgery, such as the drop in preload during the anhepatic phase (occasionally requiring massive transfusions and vasopressors) and subsequent increase in preload with acidic and hyperkalemic plasma in the reperfusion phase, lead to rapid electrolyte and hemodynamic shifts. In several cases, intraoperative onset of HF, with or without ventricular arrythmia, could be timed to the reperfusion phase (and occasionally in the anhepatic and pre-anhepatic phases). In other cases, the HF syndrome started hours to days post-surgery. Recovery of cardiac function occurred in the majority of patients during the same admission; however, these patients generally need significantly longer hospitalizations and aggressive supportive care (occasionally requiring mechanical ionotropic and ventilatory support). If recover, the patients have a similar 1-year mortality as those LT patients that did not have this complication. Because no reliable risk stratification currently exists, intraoperative transesophageal echocardiography might be the most dependable way of detecting and addressing this syndrome promptly. Given the mechanism of takotsubo cardiomyopathy, beta-blockade and a preferential use of non-catecholaminergic vasopressors may be a reasonable way to manage this syndrome.

Modeling hepatitis C virus kinetics during liver transplantation reveals the role of the liver in virus clearance.

While the liver, specifically hepatocytes, are widely accepted as the main source of hepatitis C virus (HCV) production, the role of the liver/hepatocytes in clearance of circulating HCV remains unknown. Frequent HCV kinetic data were recorded and mathematically modeled from five liver transplant patients throughout the anhepatic (absence of liver) phase and for 4 hr post-reperfusion. During the anhepatic phase, HCV remained at pre-anhepatic levels (n = 3) or declined (n = 2) with t1/2~1 hr. Immediately post-reperfusion, virus declined in a biphasic manner in four patients consisting of a rapid decline (t1/2 = 5 min) followed by a slower decline (t1/2 = 67 min). Consistent with the majority of patients in the anhepatic phase, when we monitored HCV clearance at 37°C from culture medium in the absence/presence of chronically infected hepatoma cells that were inhibited from secreting HCV, the HCV t1/2 in cell culture was longer in the absence of chronically HCV-infected cells. The results suggest that the liver plays a major role in the clearance of circulating HCV and that hepatocytes may be involved.

Correlation of Deceased Donor Factors to Postreperfusion Severe Hyperglycemia in Adult Patients Undergoing Liver Transplant.

In this study, our objective was to identify perioperative factors associated with postreperfusion severe hyperglycemia, with a particular focus on deceased donor factors. Perioperative data from 100 patients without diabetes who were undergoing liver transplant from deceased donors were reviewed. Mean blood glucose levels were calculated at each liver transplant surgical phase, with a cutoff level of 12.7 mmol/L (230 mg/dL) during the neo-hepatic phase defined as postreperfusion severe hyperglycemia. Patients were divided into those with and without postreperfusion severe hyperglycemia. Selected perioperative variables were compared between the 2 groups. Of 100 patients, 55 developed postreperfusion severe hyperglycemia. Among donor variables, a statistically significant difference between groups was only shown for graft-to-recipient liver weight ratio (P < .001). With regard to preoperative recipient variables, the 2 groups showed a significant difference in mean age (P = .001). Patients in the postreperfusion severe hyperglycemia group required significantly more packed red blood cell transfusions (P = .002), sodium bicarbonate (P = .054), and vasopressors (P = .002) during the operation. Moreover, in terms of laboratory findings, although the last arterial pH was acceptable in both groups, a last lower arterial pH was observed in patients with postreperfusion severe hyperglycemia (P = .011). Higher mean blood glucose levels were detected in the postreperfusion hyperglycemia group during the preanhepatic and anhepatic phases (P = .024, P = .001, respectively). In patients undergoing liver transplant, incidence of postreperfusion severe hyperglycemia was influenced by graft-to-recipient liver weight ratio. Furthermore, postreperfusion severe hyperglycemia was associated with intraoperative clinical and laboratory disturbances in liver transplant recipients.

Intraoperative Factors Associated With Early Recipient Death After Adult-to-Adult Living Donor Liver Transplant.

Living donor liver transplant is the gold standard therapy for patients with terminal hepatic disorders for whom no alternative therapy is available. The primary aim was to assess different intraoperative factors that may predict early death after adult-to-adult living donor liver transplant. The secondary aim was to assess the effect of small-for-size syndrome on mortality. This retrospective multicenter cohort study was performed on records from 145 adults with cirrhosis who had received a right lobe living donor liver transplant. Patients were divided according to the occurrence of short-term mortality (death within the first month after transplant). The primary intraoperative parameters included graft weight, surgical duration, mean blood pressure, serum lactate and sodium bicarbonate, transfusions, durations of cold and warm ischemia and anhepatic phase, input and output during surgery, and portal venous pressures. There were statistically significant variations between both cohorts for number of units of packed red blood cells, durations of cold and warm ischemia and anhepatic phase, preclamp and postreperfusion portal venous pressures, average urine output, mean serum lactate, mean blood pressure, and surgical duration (P ⟨ .001). Also, there were significant differences in the number of platelets, units of fresh frozen plasma, and mean sodium bicarbonate (P = .025, .003, and .035, respectively). Of the 25 patients who died within the early postoperative period, 20 had developed small-for-size syndrome (P ⟨ .001). A variety of intraoperative risk factors may affect early posttransplant mortality, which suggests the high complexity of living donor liver transplants and the need for well-trained experienced teams to perform these surgeries.