Assessing relative cost of complications following orthotopic liver transplant

Healthcare Costs and Early Complications in Liver-Transplanted Patients With Portal Vein Thrombosis: Experience From a Colombian Reference Center

OBJECTIVES

This study aimed to analyze the direct healthcare costs and early complications associated with pretransplant portal vein thrombosis (PVT) in cirrhotic patients undergoing their first orthotopic liver transplant (LT) at a hospital in Colombia from 2013 to 2021.

METHODS

A registry-based retrospective follow-up study was conducted on cirrhotic patients aged 14 years or older who underwent their first LT at the San Vicente Fundación Rionegro Hospital between January 2013 and April 2021. The primary outcomes were early (30-day) vascular and biliary complications and direct healthcare costs. The generalized linear model was used to estimate observed and adjusted mean differences in costs and risk ratios for complications based on pretransplant PVT. Costs were expressed in 2020 international dollars.

RESULTS

The medical records of 161 patients were analyzed, with 15.5% having pretransplant PVT. Patients with pretransplant PVT exhibited a statistically significant higher risk of early vascular complications (adjusted risk ratio 2.17; 95% CI 1.04-4.51; P = .039). However, there was no statistically significant difference in the risk of early biliary complications (P = .225). Patients with grade I PVT did not show a significant difference in costs compared with patients without PVT (P = .661). For patients with grade II-IV PVT, the adjusted mean difference in the healthcare cost was 33 175 international dollars (95% CI 730-65 620).

CONCLUSIONS

Patients with pretransplant grade II-IV PVT have a higher risk of early vascular complications and require more medical resources, leading to increased costs associated with LT.

[Application Value of Novel Coagulation Markers in Predicting Postoperarative Complications in the Early Stage After Liver Transplantation]

Objective

To investigate the relationship between thrombin-antithrombin complex (TAT), plasmin-α 2-plasmininhibitor complex (PIC), soluble thrombomodulin (sTM), and tissue plasminogen activator-inhibitor complex (tPAIC) and postoperative complications in the early stage after liver transplantation (LT).

Methods

We analyzed the perioperative clinical data, including plasma TAT, PIC, sTM, and tPAIC, of 130 post-LT patients admitted to the intensive care unit (ICU), West China Hospital, Sichuan University between December 2021 and November 2022. Patients were divided into two groups, a complication group and a non-complication group, according to whether they experienced complications of Clavien-Dindo (CD) grade Ⅲb and above within 30 days after the surgery. Univariate analysis and binary multivariate logistic regression models were used to determine the risk factors for complications within 30 days post-LT.

Results

The incidence of complications of CD grade Ⅲb and above within 30 days post-LT was 33.1% (43/130). Patients in the complication group had significantly higher scores for the Model for End-Stage Liver Disease (MELD), operative time, intraoperative red blood cell transfusion volume, intraoperative plasma transfusion volume, and plasma TAT, PIC, sTM and tPAIC measured at the time of admission to ICU after the operation than those in the non-complication group did (all P<0.05). Logistic regression showed that for every single U of red blood cells transfused during the transplant surgery, the probabilities of complications within 30 days post-LT increased by 15.1% (95% confidence interval [ C I]: 1.070-1.239, P<0.001) and for the increase of every single TU/mL of plasma sTM measured upon post-LT admission to ICU, the probabilities of complications increased by 13.7% (95% CI: 1.060-1.220, P<0.001).

Conclusion

Plasma sTM measured upon admission to ICU after LT is an independent risk factor for complications within 30 days post-LT, and additional assessment of sTM may help predict complications in the early stage post-LT.

Patients are pragmatic and physicians are perfectionists? Comparing success after liver transplantation among patients and physicians

Although both patients and physicians are key stakeholders in health care outcomes, patients and physicians often define success differently. The purpose of this study was to compare patient and physician perceptions of success 1 year after liver transplantation. This was a single-institution, qualitative study. We conducted in-person, semi-structured interviews with liver transplant recipients 1 year after transplantation and virtual interviews with transplant surgeons and hepatologists. Transcripts were coded and iteratively analyzed for themes using the principles of phenomenology. Twenty patients, 8 caregivers, 5 transplant surgeons, and 4 hepatologists were interviewed. Subject interviews averaged 57 (patient) and 27 (physician) minutes. Overall, patients and physicians had significant agreement in their definitions of success, which included avoidance of death, restoration of physical and mental function, return to society, acquisition of new health care knowledge, and open communication between the patient and the physician. Patients highlighted relief from worry about their future health status, and physicians highlighted decreased health care costs. Patients noted that a liver transplant did not have to be perfect, that is free from complications, to be successful. Physicians had a more stringent view and felt that any deviation from an ideal course reduced the relative success of a transplant. Detailed assessment of patient and physician responses reveals similar overall goals of regaining physical, mental, and emotional function. Complications are perceived differently by patients and physicians. Awareness of this discordance may serve to enhance relationships between transplant patients and their providers.

Performance of a Prospective Anticoagulation Stratification Algorithm After Liver Transplantation

Venous thromboembolism (VTE) occurs in 0.4% to 15.5% and bleeding occurs in 20% to 35% of patients after liver transplantation (LT). Balancing the risk of bleeding from therapeutic anticoagulation and risk of thrombosis in the postoperative period is challenging. Little evidence exists regarding the best treatment strategy for these patients. We hypothesized that a subset of LT patients who develop postoperative deep vein thromboses (DVTs) could be managed without therapeutic anticoagulation. We implemented a quality improvement (QI) initiative using a standardized Doppler ultrasound-based VTE risk stratification algorithm to guide parsimonious implementation of therapeutic anticoagulation with heparin drip.

Methods

In a prospective management QI initiative for DVT management, we compared 87 LT historical patients (control group; January 2016-December 2017) to 182 LT patients (study group; January 2018-March 2021). We analyzed the rates of immediate therapeutic anticoagulation after DVT diagnosis within 14 d of LT, clinically significant bleeding, return to the operating room, readmission, pulmonary embolism, and death within 30 d of LT before and after the QI initiative.

Results

Ten patients (11.5%) in the control group and 23 patients (12.6%; P = 0.9) in the study group developed DVTs after LT. Immediate therapeutic anticoagulation was used in 7 of 10 and 5 of 23 patients in the control and study groups, respectively (P = 0.024). The study group had lower odds of receiving immediate therapeutic anticoagulation after VTE (21.7% versus 70%; odds ratio = 0.12; 95% confidence interval, 0.019-0.587; P = 0.013) and a lower rate of postoperative bleeding (8.7% versus 40%; odds ratio = 0.14, 95% confidence interval, 0.02-0.91; P = 0.048). All other outcomes were similar.

Conclusions

Implementing a risk-stratified VTE treatment algorithm for immediate post-LT patients appears to be safe and feasible. We observed a decrease in the use of therapeutic anticoagulation and a lower rate of postoperative bleeding without adverse impacts on early outcomes.

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.

Inventing Engineered Organoids for end-stage liver failure patients

End-stage liver disease (ESLD) is a term used clinically in reference to a group of liver diseases with liver transplantation as the choice of treatment. Due to the limitations of liver transplantation, alternative treatments are needed. The use of primary human hepatocytes represents a valid alternative treatment, but the limitations related to hepatocyte quality, viability, function, conservation, and storage need to be overcome. Transplanted hepatocytes have only been followed for 6–9 months. Therefore, long-term causes of failures are not yet established, including rejection, apoptosis, or other causes. Other alternative therapies to replace liver transplantation include plasmapheresis, hemodiafiltration, and artificial livers. Unfortunately, these methods are highly limited due to availability, high cost, anaphylaxis reaction, development-deposition of immune-complexes, and restricted functionality. Liver organoids, which utilize stem cells instead of ‘impractical’ adult hepatocytes, may be a solution for the development of a complex bioartificial liver. Recent studies have explored the benefits of differentiating mature hepatocytes from stem cells inside a bioreactor. When the use of human-induced Hepatocytes (hiHeps) was investigated in mouse and pig models of liver failure, liver failure markers were decreased, hepatocyte function indicated by albumin synthesis improved, and survival time increased. Bioartificial liver treatment may decrease the infiltration of inflammatory cells into liver tissue by down-regulating pro-inflammatory cytokines.

Association between Gut Colonization of Vancomycin-resistant Enterococci and Liver Transplant Outcomes

BACKGROUND

Vancomycin-resistant enterococci (VRE) colonization is common in liver transplant recipients and has been associated with worse post-transplant outcomes.

METHODS

We conducted a retrospective cohort study at the University of Alberta Hospital including patients who underwent a liver transplant between September 2014 and December 2017.

RESULTS

Of 343 patients, 68 (19.8%) had pre-transplant VRE colonization and 27 (27/275, 9.8%) acquired VRE post-transplant, 67% were males and the median age was 56.5 years. VRE colonized patients at baseline had higher MELD scores and required longer post-transplant hospitalization. VRE colonization was associated with increased risk of early acute kidney injury (AKI) (64% vs 52%, p = 0. 044), clinically significant bacterial/fungal infection (29% vs 17%, p = 0. 012) and invasive VRE infection (5% vs 1%, p = 0. 017). Mortality at 2-years was 13% in VRE-colonized versus 7% in non-colonized (p = 0.085). On multivariate analysis, VRE colonization increased the risk of post-transplant AKI (HR 1.504, 95% CI: 1.077-2.100, p = 0.017) and clinically significant bacterial or fungal infection at 6 months (HR 2.038, 95%CI: 1.222-3.399, p = 0.006), and was associated with non-significant trend towards increased risk of mortality at 2-years post-transplant (HR 1.974 95% CI 0.890-4.378; p = 0.094).

CONCLUSIONS

VRE colonization in liver transplant patients is associated with increased risk of early AKI, clinically significant infections, and a trend towards increased mortality at 2-years. This article is protected by copyright. All rights reserved.

Effect of post-operative goal-directed fluid therapy (GDFT) on organ function after orthotopic liver transplantation: Secondary outcome analysis of the COLT randomised control trial

BACKGROUND

Goal-directed fluid therapy (GDFT) has been shown to reduce the complications following a variety of major surgical procedures, possibly mediated by improved organ perfusion and function. We have shown that it is feasible to randomise patients to GDFT or standard fluid management following liver transplant in the cardiac-output optimisation following liver transplantation (COLT) trial. The current study compares end organ function in patients from the COLT trial who received GDFT in comparison to those receiving standard care (SC) following liver transplant.

METHODS

Adult patients with liver cirrhosis undergoing liver transplantation were randomised to GDFT or SC for the first 12 h following surgery as detailed in a published trial protocol. GDFT protocol was based on stroke volume (SV) optimisation using 250 ml crystalloid boluses. Total fluid administration and time to extubation were recorded. Hourly SV and cardiac output (CO) readings were recorded from the non-invasive cardiac output monitoring (NICOM) device in both groups. Pulmonary function was assessed by arterial blood gas (ABG) and ventilatory parameters. Lung injury was assessed using PaO₂:FiO₂ ratios and calculated pulmonary compliance. The KDIGO score was used for determining acute kidney injury. Renal and liver graft function were assessed during the post-operative period and at 3 months and 1-year.

RESULTS

60 patients were randomised to GDFT (n = 30) or SC (n = 30). All patients completed the 12 h intervention period. GDFT group received a significantly higher total volume of fluid during the 12 h trial intervention period (GDFT 5317 (2335) vs. SC 3807 (1345) ml, p = 0.003); in particular crystalloids (GDFT 3968 (2073) vs. SC 2510 (1027) ml, p = 0.002). There was no evidence of significant difference between the groups in SV or CO during the assessment periods. Time to extubation, PaO2: FIO₂ ratios, pulmonary compliance, ventilatory or blood gas measurements were similar in both groups. There was a significant rise in serum creatinine from baseline (77 μmol/L) compared to first (87 μmol/L, p = 0.039) and second (107 μmol/L, p = 0.001) post-operative days. There was no difference between GDFT and SC in the highest KDIGO scores for the first 7 days post-LT. At 1-year follow-up, there was no difference in need for renal replacement therapy or graft function.

CONCLUSIONS

In this randomised trial of fluid therapy post liver transplant, GDFT was associated with an increased volume of crystalloids administered but did not alter early post-operative pulmonary or renal function when compared with standard care.

Cost-utility analysis of normothermic machine perfusion compared to static cold storage in liver transplantation in the Canadian setting

To estimate the incremental cost-effectiveness of a liver transplant program that utilizes normothermic machine perfusion (NMP) alongside static cold storage (SCS) compared to SCS alone (control). A Markov model compared strategies (NMP vs. control) using 1-year cycle lengths over a 5-year time horizon from the public healthcare payer perspective. Primary micro-costing data from a single center retrospective trial were applied along with utility values from literature sources. Transition probabilities were deduced using the retrospective trial cohort, local transplant data, and supplemented with literature values. Scenario and probabilistic sensitivity analysis (PSA) were conducted. The NMP strategy was cost-effective in comparison to the control strategy, which was dominated. The mean cost for NMP was $456 455 (2021 US$) and the control was $519 222. The NMP strategy had greater incremental quality-adjusted life years (QALYs) gains over 5 years compared to the control, with 3.48 versus 3.17, respectively. The overarching results remained unchanged in scenario analysis. In PSA, NMP was cost-effective in 63% of iterations at a willingness-to-pay threshold of $40 941. The addition of NMP to a liver transplant program results in greater QALY gains and is cost-effective from the public healthcare payer perspective.

Hepatic Encephalopathy: From Metabolic to Neurodegenerative

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome of both acute and chronic liver disease. As a metabolic disorder, HE is considered to be reversible and therefore is expected to resolve following the replacement of the diseased liver with a healthy liver. However, persisting neurological complications are observed in up to 47% of transplanted patients. Several retrospective studies have shown that patients with a history of HE, particularly overt-HE, had persistent neurological complications even after liver transplantation (LT). These enduring neurological conditions significantly affect patient's quality of life and continue to add to the economic burden of chronic liver disease on health care systems. This review discusses the journey of the brain through the progression of liver disease, entering the invasive surgical procedure of LT and the conditions associated with the post-transplant period. In particular, it will discuss the vulnerability of the HE brain to peri-operative factors and post-LT conditions which may explain non-resolved neurological impairment following LT. In addition, the review will provide evidence; (i) supporting overt-HE impacts on neurological complications post-LT; (ii) that overt-HE leads to permanent neuronal injury and (iii) the pathophysiological role of ammonia toxicity on astrocyte and neuronal injury/damage. Together, these findings will provide new insights on the underlying mechanisms leading to neurological complications post-LT.

Cost Utilization and the Use of Pulmonary Function Tests in Preoperative Liver Transplant Patients

BACKGROUND

Pulmonary function tests (PFTs) are currently recommended for liver transplant candidates. We hypothesized that PFTs may not provide added clinical value to the evaluation of liver transplant patients.

METHODS

We conducted a retrospective cohort study of adult cadaveric liver transplants from 2012 to 2018. Abnormal PFTs were defined as restrictive disease of diffusing capacity of the lungs for carbon monoxide (DLCO) <80% or obstructive disease of ratio of forced expiratory volume in the first 1 second to the first vital capacity of the lungs (FEV1/FVC) <70%.

RESULTS

We analyzed data on 415 liver transplant patients (358 abnormal PFT results and 57 normal results). The liver transplant patients with abnormal PFTs had no difference in number of intensive care unit (ICU) days (P = .68), length of stay (P = .24), or intubation days (P = .33). There were no differences in pulmonary complications including pleural effusion (P = .30), hemo/pneumothorax (P = .74), pneumonia (P = .66), acute respiratory distress syndrome (P = .57), or pulmonary edema (P = .73). The significant finding between groups was a higher rate of reintubation in liver transplant patients with normal PFTs (P = .02). There was no difference in graft survival (P = .53) or patient survival (P = .42).

DISCUSSION

Abnormal PFTs, found in 86% of liver transplant patients, did not correlate with complications, graft failure, or mortality. PFTs contribute to the high cost of liver transplants but do not help predict which patients are at risk of postoperative complications.

Incidence of Bleeding and Thrombosis in Patients with Liver Disease

Historically, liver disease has been associated with a bleeding tendency. Global hemostatic assays have demonstrated that hemostasis is overall rebalanced, in both acute liver failure and chronic liver disease. It is now recognized that many bleeding events in chronic liver disease are mediated by portal hypertension rather than an underlying hemostatic defect. This is acknowledged in recent guidelines, which recommend against coagulation testing prior to low risk procedures in this patient group, with avoidance also of attempts at correction of prolonged coagulation times. Over time, the incidence of bleeding events has decreased in both chronic liver disease and acute liver failure, with improved supportive care, targeted treatments for underlying cause of liver disease, and the advent of liver transplantation. Concurrently, there has been increased recognition of the risk of thrombosis in chronic liver disease, with a predilection for the splanchnic vasculature. This review describes the incidence of bleeding and thrombosis in chronic liver disease and acute liver failure, including the periprocedural and liver transplantation setting.

Neurological Complications After Renal Transplantation: A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to evaluate the prevalence of neurological complication after renal transplantation. The searches were conducted by two independent researchers in the international (PubMed, Web of Science, Scopus, and Google Scholar) and national databases (Magiran and SID) to find the relevant studies published in English and Persian languages since the creation of the databases until January 2019 (without time limitations). The keywords used in the search strategy were: neurologic complication, central nervous system, peripheral nervous system, tremor, CVA, encephalopathy, neurological complications, renal transplantation, renal failure, kidney transplantation, immunosuppression, neurotoxicity, opportunistic infections, CNS, cerebrovascular disease, chronic kidney disease, cognitive impairment, and end-stage renal disease, which were combined using the AND, OR, and NOT operators. Finally, a meta-analysis was conducted in STATA14 statistical software. Based on the random effect model, the total prevalence of neurologic complications in 4674 patients who had undergone the renal transplantation surgery was 7.9% (95% confidence interval [CI]:7.2%,8.7%, I² = 90.1%). The prevalence of infectious, non-infectious and treatment associated neurologic complications was 9.5% (95% CI -8.9, 10.2), 91.8% (95% CI -91.3, 92.4) and 97% (95% CI-95.7%,98.4%) of all neurologic complications in renal transplant patients, respectively. And according to the present subgroup analysis, peripheral neuropathy with a prevalence about 30% (29%) (95% CI -27.6%, 30.4%, I² = 99.4%) was the most common neurological disorder in renal transplant patients followed by tremor with a prevalence of 19.5% (CI -17.6%, 21.3%, I² = 97.1%), cerebrovascular events with a prevalence of 15.1% (95% CI -13.9%, 16.4%, I² = 96.5%), encephalopathy with the prevalence of 13% (95% CI -12%, 14%, I² = 99.3%), headache with a prevalence of 8.3% (95% CI -6.8%, 9.8%, I² = 97.3%) and seizure with a prevalence of 7.4% (CI - 6.5%, 8.3%, I² = 94.6%). The results of the present systematic review and meta-analysis, suggests that post-kidney transplantation neurological disorders, with a prevalence rate about 8%, are relatively common; most of them are caused by immunosuppressive drugs and can be treated by decreasing the dose or switching the immunosuppressive drugs. Neurological disorders are associated with increased mortality; thus, differential diagnosis should be conducted for each individual patient with neurological symptoms after transplantation. It is important for all health care providers to become familiar with the symptoms of neurological disorders that may occur after organ transplants. Recognizing and monitoring these symptoms can reduce the risk of death in kidney transplant recipients. Further research is needed to help the transplant community to identify these issues and problems better in order to achieve the ultimate goal of helping renal patients and sending them back into their normal lives.

Abdominal Organ Transplantation: Noteworthy Literature in 2018

A PubMed search revealed 1382 articles on pancreatic transplantation, 781 on intestinal transplantation, more than 7200 on kidney transplantation, and more than 5500 on liver transplantation published between January 1, 2018, and December 31, 2018. After narrowing the list down to human studies, 436 pancreatic, 302 intestinal, 1920 liver, and more than 2000 kidney transplantation studies were screened for inclusion in this review.