Risk Factors for Early Mortality in Liver Transplant Patients

A nomogram for predicting early bacterial infection after liver transplantation: a retrospective study

Background

Bacterial infection is a common complication of liver transplantation and is associated with high mortality rates. However, multifactor-based early-prediction tools are currently lacking. Therefore, this study investigated the risk factors of early bacterial infections after liver transplantation and used them to establish a nomogram.

Methods

We retrospectively collected the clinical data of 232 patients who underwent liver transplantation. We excluded 15 patients aged less than 18 years, 7 patients with infection before transplantation, and 3 patients with incomplete laboratory test results based on the sample exclusion criteria, and finally included 207 liver transplant patients. The patients were divided into the bacterial infection group (75 cases) and non-infected group (132 cases) according to whether bacterial infection had occurred within 30 days after surgery. The associated risk factors were determined using stepwise regression, and a nomogram was established based on the results of the multifactorial analysis. The predictive performance of the model was compared by assessing the area under the receiver operating characteristic curve (AUC-ROC), decision curve analysis (DCA), and the calibration curve, which was validated using cross-validation and repeated sampling.

Result

Preoperative systemic immune inflammation index (SII) (OR = 1.003, p = 0.001), duration of surgery (OR = 1.008, p = 0.005), duration of postoperative ventilator use (OR = 1.013, p = 0.025), neutrophil to lymphocyte ratio (NLR) (OR = 1.017, p = 0.024), ICU stay time (OR = 1.125, p = 0.015) were independent risk factors for early bacterial infection after liver transplantation. The nomogram was constructed based on the above factors, achieving an AUC of 0.863 (95%CI: 0.808, 0.918), which showed that the mean absolute error between the predicted risk and the actual risk of the model was 0.044. The decision curve analysis showed that it was located above both extreme curves in a range of more than the 14% threshold, which indicated that there was a good clinical benefit in this range. Internal validation using 10-fold cross validation and bootstrap replicate sampling yielded areas under the corrected ROC curves of 0.842 and 0.854, respectively. These results indicate that the developed model exhibits good predictive performance and a moderate error in training and validation.

Conclusion

The nomogram constructed in this study showed good differentiation, calibration, and clinical applicability. It can effectively identify the high-risk group for bacterial infection in the early postoperative period after liver transplantation, while simultaneously helping the transplant team dynamically monitor the key indicators and optimize perioperative management.

Associations Between Social Support, Health Literacy and Psychological Resilience to Self-Management Behaviours in Liver Transplant Recipients-A Structural Equation Model

AIMS

This study aimed to develop a structural model to elucidate the contributions of social support, health literacy and psychological resilience to self-management behaviours in liver transplant recipients after surgery.

DESIGN

Cross-sectional study.

METHODS

This study included 215 Chinese patients who returned to the outpatient department after liver transplantation between June 2023 and March 2024. Data were collected via a general demographic questionnaire, a self-management questionnaire for liver transplant recipients, a chronic disease resource questionnaire, the Connor-Davidson resilience scale and the health literacy scale for chronic patients. Correlation analysis and structural equation modelling were utilised to analyse the relationships among social support, health literacy, psychological resilience and self-management ability.

RESULTS

The final model showed good fit (χ2/df = 1.690, GFI = 0.919, IFI = 0.951, TLI = 0.938, CFI = 0.950 and RMSEA = 0.057). The direct effect coefficient of social support on self-management ability is 0.293. The indirect effect value of health literacy on the relationship between social support and self-management ability was 0.312, whereas the indirect effect value of psychological resilience in this context was 0.096. Furthermore, the chain-mediating effect involving both health literacy and psychological resilience between social support and self-management ability was 0.109.

CONCLUSION

The revised model, grounded in social cognitive theory, demonstrated a strong fit for predicting self-management behaviours among liver transplant recipients. Furthermore, social support, health literacy and psychological resilience exerted both direct and indirect influences on the self-management behaviours of these recipients.

REPORTING METHOD

Strengthening the Reporting of Observational Studies in Epidemiology (STROBE).

PATIENT OR PUBLIC CONTRIBUTION

In public or patient involvement in this study.

Computer-Aided Diagnosis of Complications After Liver Transplantation Based on Transfer Learning

Liver transplantation is one of the most effective treatments for acute liver failure, cirrhosis, and even liver cancer. The prediction of postoperative complications is of great significance for liver transplantation. However, the existing prediction methods based on traditional machine learning are often unavailable or unreliable due to the insufficient amount of real liver transplantation data. Therefore, we propose a new framework to increase the accuracy of computer-aided diagnosis of complications after liver transplantation with transfer learning, which can handle small-scale but high-dimensional data problems. Furthermore, since data samples are often high dimensional in the real world, capturing key features that influence postoperative complications can help make the correct diagnosis for patients. So, we also introduce the SHapley Additive exPlanation (SHAP) method into our framework for exploring the key features of postoperative complications. We used data obtained from 425 patients with 456 features in our experiments. Experimental results show that our approach outperforms all compared baseline methods in predicting postoperative complications. In our work, the average precision, the mean recall, and the mean F1 score reach 91.22%, 91.70%, and 91.18%, respectively.

Predictors of intraoperative massive transfusion in orthotopic liver transplantation

BACKGROUND

Although transfusion management has improved during the last decade, orthotopic liver transplantation (OLT) has been associated with considerable blood transfusion requirements which poses some challenges in securing blood bank inventories. Defining the predictors of massive blood transfusion before surgery will allow the blood bank to better manage patients' needs without delays. We evaluated the predictors of intraoperative massive transfusion in OLT.

STUDY DESIGN AND METHODS

Data were collected on patients who underwent OLT between 2007 and 2017. Repeat OLTs were excluded. Analyzed variables included recipients' demographic and pretransplant laboratory variables, donors' data, and intraoperative variables. Massive transfusion was defined as intraoperative transfusion of ≥10 units of packed red blood cells (RBCs). Statistical analysis was performed using SPSS version 17.0.

RESULTS

The study included 970 OLT patients. The median age of patients was 57 (range: 16-74) years; 609 (62.7%) were male. RBCs, thawed plasma, and platelets were transfused intraoperatively to 782 (80.6%) patients, 831 (85.7%) patients, and 422 (43.5%) patients, respectively. Massive transfusion was documented in 119 (12.3%) patients. In multivariate analysis, previous right abdominal surgery, the recipient's hemoglobin, Model for End Stage Liver Disease (MELD) score, cold ischemia time, warm ischemia time, and operation time were predictive of massive transfusion. There was a direct significant correlation between the number of RBC units transfused and plasma (Pearson correlation coefficient r = .794) and platelets (r = .65).

DISCUSSION

Previous abdominal surgery, the recipient's hemoglobin, MELD score, cold ischemia time, warm ischemia time, and operation time were predictive of intraoperative massive transfusion in OLT.

Epidemiology and Prevention of Early Infections by Multi-Drug-Resistant Organisms in Adults Undergoing Liver Transplant: A Narrative Review

Invasive bacterial infections are a leading cause of morbidity and mortality after liver transplant (LT), especially during the first months after LT, and infections due to multi-drug-resistant organisms (MDRO) are increasing in this setting. Most of the infections in patients in intensive care unit arise from the endogenous microflora and, for this reason, pre-LT MDRO rectal colonization is a risk factor for developing MDRO infections in the post-LT. Moreover, the transplanted liver may carry an increased risk of MDRO infections due to organ transportation and preservation, to donor intensive care unit stay and previous antibiotic exposure. To date, little evidence is available about how MDRO pre-LT colonization in donors and recipients should address LT preventive and antibiotic prophylactic strategies, in order to reduce MDRO infections in the post-LT period. The present review provided an extensive overview of the recent literature on these topics, with the aim to offer a comprehensive insight about the epidemiology of MDRO colonization and infections in adult LT recipients, donor-derived MDRO infections, possible surveillance, and prophylactic strategies to reduce post-LT MDRO infections.

Fibrinolysis resistance after liver transplant as a predictor of early infection

BACKGROUND

Infection is a leading cause of morbidity in liver transplant (LT). Considering that the fibrinolytic system is altered in sepsis, we investigated the relationship between fibrinolysis resistance (FR) and post-transplant infection.

METHODS

Fibrinolysis was quantified using thrombelastography (TEG) with the addition of tPA to quantify FR. FR was defined as LY30 = 0% and stratified as transient if present on POD1 or POD5 (tFR), persistent (pFR) if present on both, or no FR (nFR) if absent.

RESULTS

180 LT recipients were prospectively enrolled. 52 (29%) recipients developed infection. 72 had tFR; 37 had pFR; and 71 had nFR. Recipients with pFR had significantly greater incidence of infections (51% vs. 26% tFR vs. 20% nFR, p = 0.002). pFR was independently associated with increased odds of post-transplant infection (adjusted OR 3.39, p = 0.009).

CONCLUSIONS

Persistent fibrinolysis resistance is associated with increased risk of post-transplant infection.

Impact of allograft types on outcomes after pediatric liver transplantation due to biliary atresia

BACKGROUND

Several surgical strategies, including split donor transplantation and living donor transplantation, have been used to increase the donor liver pool. This report focuses on the effects of whole, split, and LDLT on recipient outcomes.

METHODS

We retrospectively analyzed the records of all patients with biliary atresia at Tianjin First Central Hospital between April 2013 and December 2019.

RESULTS

A total of 882 patients were included and divided into three groups by graft type, with 198 in the whole-liver-transplantation group, 78 in the split liver transplantation group, and 606 in the LDLT group. The median follow-up time was 39 months, patient survival rates of three groups were 94.4%, 88.5%, and 95.0%, respectively, and graft survival rates were 90.2%, 83.3%, and 94.7%, respectively. We divided the split liver transplantation group into two subgroups according to the donor's age, and patient survival rates exhibited a significant difference only in the group whose donor age was over 45 years. The postoperative complication rates were significantly higher with respect to hepatic artery thrombosis, portal stenosis, and AR; and lower in hepatic venous stenosis, PTLDs, CMV virus, and EBV infection in the WLT group. Our multivariate model showed that donor age ≥45 years, RBC transfusion, pneumonia, and HAT were the independent predictors of allograft loss.

CONCLUSIONS

The survival of split liver transplantation group was slightly lower. The types of complications are different from different graft types. Therefore, postoperative monitoring and treatment need to be adjusted according to the different graft types used.

Comparison of the long-term outcomes of patients with hepatocellular carcinoma within the Milan criteria treated by ablation, resection, or transplantation

BACKGROUND

Liver transplantation (LT), resection (LR), and ablation (LA) are three curative-intent treatment options for patients with early hepatocellular carcinoma (HCC). We aimed to develop a prognostic calculator to compare the long-term outcomes following each of these therapies.

METHODS

A total of 976 patients with HCC within the Milan criteria who underwent LT, LR, and LA between 2009 and 2019 from four institutions were evaluated. Multistate competing risks prediction models for recurrence-free survival (RFS), recurrence within the Milan criteria (RWM), and HCC-specific survival (HSS) were derived to develop a prognostic calculator.

RESULTS

During a median follow-up of 51 months, 420 (43%) patients developed recurrence. In the multivariate analysis, larger tumor size, multinodularity, older age, male, higher alpha-fetoprotein (AFP), higher albumin-bilirubin (ALBI) grade, and the presence of portal hypertension were significantly associated with higher recurrence and decreased survival rates. The RFS and HSS were both significantly higher among patients treated by LT than by LR or LA and significantly higher between patients treated by LR than by LA (all p < 0.001). For multinodular HCC ≤3 cm, although LT had better RFS and HSS than LR or LA, LA was noninferior to LR. An online prognostic calculator was then developed based on the preoperative clinical factors that were independently associated with outcomes to evaluate RFS, RWM, and HSS at different time intervals for all three treatment options.

CONCLUSIONS

Although LT resulted in the best recurrence and survival outcomes, LR and LA also offered durable long-term alternatives. This prognostic calculator is a useful tool for clinicians to guide an informed and personalized discussion with patients based on their tumor biology and liver function.

Clinical impact of the Model for End Liver Disease (MELD) score on the presence of microvascular invasion and on the postoperative outcome in patients undergoing liver transplantation

OBJECTIVE

to correlate clinical and epidemiological data with the pathological analysis of liver explants from patients undergoing liver transplantation for hetapocarcinoma in the UNICAMP HC and to verify whether the MELD and MELD-Na scores are reliable factors to predict a worse post-transplant prognosis.

METHODS

we studied liver transplants carried out between May 2010 and November 2017. After excluding 38 patients, we included 87, analyzing clinical and laboratory data for correlation with the outcome Microvascular Invasion (MVI). Subsequently, we computed the MELD and MELD-Na scores and performed a descriptive analysis of clinical and laboratory data and, finally, calculated ROC curves to assess the association between these laboratory parameters and mortality in these patients.

RESULTS

most patients were male (78.30%), with an average age of 58.53 years. Most liver diseases were caused by HCV (53.26%). We found no predictors for MVI among the laboratory parameters. The ROC curves for death identified the MELD score as the cutoff point with the highest combined sensitivity (90.91%) and specificity (37.50%), with a value of 10 points, whereas in the MELD-Na the cutoff point was 7 points, with a sensitivity of 90.91% and a specificity of 33.33%, both scores being significant.

CONCLUSIONS

there were no reliable predictors of MVI between clinical, laboratory, and epidemiological variables. The MELD-Na score is more sensitive than the MELD one for predicting mortality in patients undergoing liver transplantation.

Transfusion requirements and alloimmunization to red blood cell antigens in orthotopic liver transplantation

BACKGROUND AND OBJECTIVES

Orthotopic liver transplantation (OLT) has been associated with high blood transfusion requirements. We evaluated the transfusion needs and frequency of alloimmunization to RBC antigens among OLT recipients pre- and post-transplantation.

MATERIALS AND METHODS

We reviewed the medical records of patients who underwent a first OLT between January 2007 and June 2017. Transfusions given only during the perioperative period, defined by 1 week before OLT until 2 weeks following OLT, were included in this study. Records were reviewed in June 2019 for updated antibody testing results.

RESULTS

A total of 970 patients underwent OLT during the study period. The median age of patients was 57 years; 608(62.7%) were male. During the perioperative period, transfused patients received an average of 10.7 (±10.7) RBC units, 15.6 (±16.2) thawed plasma units and 4.1 (±4.3) platelet units. At the time of OLT, a total of 101 clinically significant RBC alloantibodies were documented in 58(5.98%) patients. Fifty-three of these antibodies were directed against Rh blood group antigens. Twenty-two (37.9%) patients had more than one alloantibody. Patients with alloimmunization before OLT (N = 58) received perioperatively comparable number of RBCs to non-alloimmunized patients (10.5 ± 10.6 vs. 9.6 ± 10.7; p = 0.52). There was no significant difference in perioperative or intraoperative RBC transfusion between patients with one alloantibody and those with multiple alloantibodies. Only 16 patients (16/737; 2.17%) developed new alloantibodies at a median of 61 days after OLT. The overall alloimmunization rate was 9.8% (72/737), and female patients were more likely to be alloimmunized.

CONCLUSION

Blood transfusion requirements in OLT remain high. However, the rate of RBC alloimmunization was not higher than the general patient population.

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

OBJECTIVES

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.

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

The Impact of Intraoperative Donor Blood on Packed Red Blood Cell Transfusion During Deceased Donor Liver Transplantation: A Retrospective Cohort Study

BACKGROUND

Blood from deceased organ donors, also known as donor blood (DB), has the potential to reduce the need for packed red blood cells (PRBCs) during liver transplantation (LT). We hypothesized that DB removed during organ procurement is a viable resource that could reduce the need for PRBCs during LT.

METHODS

We retrospectively examined data on LT recipients aged over 18 y who underwent a deceased donor LT. The primary aim was to compare the incidence of PRBC transfusion in LT patients who received intraoperative DB (the DB group) to those who did not (the nondonor blood [NDB] group).

RESULTS

After a propensity score matching process, 175 patients received DB and 175 did not. The median (first-third quartile) volume of DB transfused was 690.0 mL (500.0-900.0), equivalent to a median of 3.1 units (2.3-4.1). More patients in the NDB group received an intraoperative PRBC transfusion than in the DB group: 74.3% (95% confidence intervals, 67.8-80.8) compared with 60% (95% confidence intervals, 52.7-67.3); P = 0.004. The median number of PRBCs transfused intraoperatively was higher in the NDB group compared with the DB group: 3 units (0-6) compared with 2 units (0-4); P = 0.004. There were no significant differences observed in the secondary outcomes.

CONCLUSIONS

Use of DB removed during organ procurement and reinfused to the recipient is a viable resource for reducing the requirements for PRBCs during LT. Use of DB minimizes the exposure of the recipient to multiple donor sources.

The Impact of Previous Abdominal Surgery in a High-Acuity Liver Transplant Population

BACKGROUND

It is not uncommon for liver transplant (LT) recipients to have had previous abdominal surgery (PAS) preceding transplant. The impact of PAS on morbidity and mortality in LT patients remains unclear. In this study, we investigated the correlation between PAS and LT outcomes in a high-acuity patient population.

MATERIALS AND METHODS

This is a single-center retrospective review of 936 adult primary LT recipients between 2012 and 2018. Patients were divided based on PAS history. PAS was subdivided into upper abdominal surgery (UAS) and lower abdominal surgery (LAS). UAS was separated into high-impact UAS and low-impact UAS. Finally, we studied patients with PAS ≤90 d versus PAS >90 d.

RESULTS

Extensive adhesiolysis was the only significant perioperative factor between the PAS group (n = 367) and the non-PAS group (n = 569) (P < 0.001). Red blood cell (RBC) transfusion (20U versus 17U, P = 0.044) and abdominal packing (24.2% versus 13.3%, P = 0.008) were significantly higher in the UAS group (n = 186) versus the LAS group (n = 181). Patients with high-impact UAS required greater RBC (P = 0.021) and fresh frozen plasma transfusion (P = 0.005), and arterial conduits (P = 0.016) during LT. Compared with recipients with PAS >90 d (n = 338), recipients with PAS ≤90 d (n = 29) had significantly higher RBC transfusion (P = 0.046), fresh frozen plasma transfusion (P = 0.022), and abdominal packing (P = 0.025). No differences in patient and graft survival was observed.

CONCLUSIONS

These findings suggest that, with appropriate care in the perioperative setting, PAS is not a contraindication to successful LT. Careful consideration is warranted when risk stratifying patients with multiple comorbidities who had PAS, especially those with UAS or PAS ≤90 d.

A clinical coagulopathy score concurrent with viscoelastic testing defines opportunities to improve hemostatic resuscitation and enhance blood product utilization during liver transplantation

BACKGROUND

An NIH clinical coagulopathy score has been devised for trauma patients, but no such clinical score exists in transplantation surgery. We hypothesize that that this coagulopathy score can effectively identify laboratory defined coagulopathy during liver transplantation and correlates to blood product utilization.

METHODS

TEGs were performed and coagulopathy scores (1, normal bleeding - 5, diffuse coagulopathic bleeding) were assigned by the surgeons at 5 intra-operative time points. Blood products used during the case were recorded between time points. Statistical analyses were performed to identify correlations between coagulopathy scores, TEG-detected abnormalities, and blood product utilization.

RESULT

Transfusions rarely correlated with the appropriate TEG measurements of coagulation dysfunction. Coagulopathy score had significant correlation to various transfusions and TEG-detected coagulopathies at multiple points during the case. High aggregate coagulopathy scores identified patients receiving more transfusions, re-operations, and longer hospital stays CONCLUSION: The combination of viscoelastic testing and a standardized clinical coagulopathy score has the potential to optimize transfusions if used in tandem as well as standardize communication between surgery and anesthesia teams about clinically evident coagulopathy.