Liver support systems and liver transplantation in acute liver failure

Comparative Analysis of Plasmapheresis Versus Plasmapheresis Combined With Continuous Renal Replacement Therapy in Adult Liver Failure: A Retrospective Observational Study

BACKGROUND

Liver failure constitutes a critical medical condition marked by the rapid decline in hepatic functions. Novel therapeutic approaches, including therapeutic plasma exchange (TPE) and continuous venovenous hemodiafiltration (CVVHDF), have emerged as promising modalities for mitigating the effects of this condition by facilitating detoxification and enhancing liver function. The efficacy of these interventions, whether administered individually or in combination, is a prominent area of investigation in the management of liver failure among adult populations. This study aims to evaluate the role and effectiveness of TPE, both as a standalone treatment and in conjunction with CVVHDF, in the management of liver failure in adult patients.

METHODS

This retrospective study was conducted in a Liver Transplant Intensive Care Unit (LTICU), focusing on the medical records of adult patients aged 35 to 62 years. The patient cohort consisted of individuals admitted between January 1, 2021, and June 1, 2024, due to acute liver failure or acute-on-chronic liver failure. The analysis specifically included patients who underwent therapeutic plasma exchange (TPE) or those who received continuous renal replacement therapy in conjunction with TPE. For the statistical analysis, a P-value of less than .05 was deemed indicative of statistical significance. The study encompassed a total of 47 patients with liver failure, comprising 23 males and 24 females. Among these patients, 25 (53.2%) received only TPE, while 22 (46.8%) were treated with a combination of TPE and continuous venovenous hemodiafiltration (CVVHDF).

RESULTS

In the cohort of patients who received only therapeutic plasma exchange (TPE), the median International Normalized Ratio (INR) improved significantly, decreasing from 2 (1.6-2.6) to 1.3 (1.1-1.7). Similarly, alanine aminotransferase levels reduced from 351 (66-1482) to 166 (71-367), while aspartate aminotransferase levels decreased from 259 (132-1392) to 86 (35-160). In the group receiving a combination of TPE and continuous venovenous hemodiafiltration (CVVHDF), notable reductions were also observed: INR decreased from 3 (2.4-4.7) to 1.5 (1.3-2.4), alanine aminotransferase levels dropped from 691 (59-2397) to 162 (70-1060), and aspartate aminotransferase levels fell from 916 (134-1828) to 69 (45-503). These changes were statistically significant, with P-values of less than .05 for each parameter in both treatment groups. Overall, 21 patients achieved survival without requiring a liver transplant, while 7 patients underwent liver transplantation, resulting in a transplant-free survival rate of 44.7%.

CONCLUSION

The findings from our study on the management of liver failure in adults demonstrate that both therapeutic plasma exchange (TPE) administered alone and in conjunction with continuous venovenous hemodiafiltration (CVVHDF) are effective treatment modalities, particularly as a bridging strategy to liver transplantation. The observed transplant-free survival rate of 44.7% underscores the significant clinical advantages of these therapies. However, to enhance the validity of these results and their applicability in broader clinical contexts, additional multicenter studies are essential for further exploration of these treatment approaches in liver failure management.

Role of continuous renal replacement therapy in management of the preliver transplant patient

PURPOSE OF REVIEW

Highlight the importance of acute kidney injury (AKI) among liver transplant candidates, its importance of survival and the vital role of continuous renal replacement therapy (CRRT) as a supportive therapy.

RECENT FINDINGS

Kidney dysfunction is common in the preliver transplant patient. Early recognition, broad diagnostic work up, and therapeutic interventions are vital in minimizing morbidity and mortality in this critically ill group of patients. Liver dysfunction can impact kidney function in multiple ways, leading to worsening of clinical illness. High mortality and poor prognosis in those with AKI without CRRT and Liver Transplant are highlighted.

SUMMARY

Etiology of AKI may not be as important as is the potential for liver transplant (LT) listing in offering CRRT. Non eligibility for a LT does not by default imply non eligibility for CRRT. Multidisciplinary approach should be adopted among those with a need for CRRT in the setting of end-stage liver disease. Goals of care conversations are key, in evaluating the role of CRRT in this group of individuals as they have a very high risk of mortality.

Continuous renal replacement therapy and survival in acute liver failure: A systematic review and meta-analysis

OBJECTIVE

Acute liver failure (ALF) is a rare syndrome leading to significant morbidity and mortality. An important cause of mortality is cerebral edema due to hyperammonemia. Different therapies for hyperammonemia have been assessed including continuous renal replacement therapy (CRRT). We conducted a systematic review and meta-analysis to determine the efficacy of CRRT in ALF patients.

MATERIALS AND METHODS

We searched MEDLINE, EMBASE, Cochrane Library, and Web of Science. Inclusion criteria included adult patients admitted to an ICU with ALF. Intervention was the use of CRRT for one or more indications with the comparator being standard care without the use of CRRT. Outcomes of interest were overall survival, transplant-free survival (TFS), mortality and changes in serum ammonia levels.

RESULTS

In total, 305 patients underwent CRRT while 1137 patients did not receive CRRT. CRRT was associated with improved overall survival [risk ratio (RR) 0.83, 95% confidence interval (CI) 0.70-0.99, p-value 0.04, I2 = 50%] and improved TFS (RR 0.65, 95% CI 0.49-0.85, p-value 0.002, I2 = 25%). There was a trend towards higher mortality with no CRRT (RR 1.24, 95% CI 0.84-1.81, p-value 0.28, I2 = 37%). Ammonia clearance data was unable to be pooled and was not analyzable.

CONCLUSION

Use of CRRT in ALF patients is associated with improved overall and transplant-free survival compared to no CRRT.

Extra-corporeal non-liver transplant therapies for acute liver failure: Focus on plasma exchange and continuous renal replacement therapy

The acute inflammatory milieu in patients with acute liver failure (ALF) results in 'toxic' blood in these patients. In vitro experiments have shown that the plasma obtained from ALF patients is toxic to rabbit hepatocytes and inhibits regeneration of rat hepatocytes. Treatments such as plasma exchange and continuous renal replacement therapy to cleanse the blood have improved survival in ALF patients. In the liver microcirculation, the exchange of fluid across fenestrae in liver sinusoidal endothelial cells (LSECs) is vital for proper functioning of hepatocytes. Clogging of the liver filter bed by inflammatory debris and cells ('traffic jam hypothesis') impeding blood flow in sinusoids may in turn reduce the exchange of fluid across LSEC fenestrae and cause dysfunction and necrosis of hepatocytes in ALF patients. In mouse model of paracetamol overdose, disturbances in microcirculation in the liver preceded the development of injury and necrosis of hepatocytes. This may represent a reversible pathophysiological mechanism in ALF which may be improved by the anti-inflammatory effect of plasma exchange. Wider access to urgent plasma exchange is a major advantage compared to urgent liver transplantation to treat ALF patients worldwide, especially so in resource constrained settings. Continuous hemo-filtration or dialysis is used to reduce ammonia levels and treat cerebral edema in ALF patients. In this review, we discuss the different modalities to cleanse the blood in ALF patients, with an emphasis on plasma exchange, from a hepatology perspective.

Single-center experience in 127 adult patients, mono or dual artificial liver support therapy, in patients with acute liver failure

Background

Acute liver failure (ALF) is a serious condition characterized by sudden liver dysfunction, jaundice and hepatic encephalopathy. Its mortality rate of approximately 80% underscores the urgent need for effective treatments. Supportive extracorporeal therapies (SET), which temporarily support liver function and remove toxins, have shown promise in improving outcomes in acute liver failure (ALF). The aim of this study was to compare the outcomes of dual supportive extracorporeal therapy (SET) and mono supportive extracorporeal therapy in patients with acute liver failure.

Methods

A total of 127 patients with acute liver failure were included in this retrospective, single-center study. Of these, 62 patients received dual supportive extracorporeal therapy and 65 patients received mono supportive extracorporeal therapy. Primary endpoints were survival without the need for liver transplantation and mortality. Secondary endpoints included resolution of encephalopathy and normalization of International Normalized Ratio (INR).

Results

In the dual supportive extracorporeal therapy group, 59.6% of patients survived without the need for liver transplantation, while 27.4% achieved recovery with liver transplantation. The mortality rate in this group was 12.9%. Significant regression of encephalopathy grade was observed in 87% of patients, and the 1 year mortality rate for liver transplant recipients was 10.7%. In the mono supportive extracorporeal therapy group, 61.5% of patients experienced a successful recovery without the need for liver transplantation, with a mortality rate of 29.2%. Significant improvement in the grade of encephalopathy was observed in 70.7% of patients.

Conclusion

Both dual supportive extracorporeal therapy (CVVHDF and PE) and mono supportive extracorporeal therapy (PE) were associated with significant improvements in renal and hepatic biochemical parameters, blood ammonia levels, and neurological status in patients with acute liver failure associated with grade III-IV hepatic encephalopathy. In particular, dual support was associated with improved hemodynamic stability, lactic acidosis and acid-base balance. Survival in acute liver failure in our retrospective cohort using a protocolized approach to extracorporeal therapies is higher compared to previously published large ALF studies. This protocolized approach warrants further prospective studies.