A comparison among three different apheretic techniques for treatment of hyperbilirubinemia

Extracorporeal liver support techniques: a comparison

ExtraCorporeal Liver Support (ECLS) systems were developed with the aim of supporting the liver in its detoxification function by clearing the blood from hepatic toxic molecules. We conducted a retrospective comparative analysis on patients presenting with liver failure who were treated with different extracorporeal techniques in our intensive care unit to evaluate and compare their detoxification abilities. To verify the effectiveness of the techniques, mass balance (MB) and adsorption per hour were calculated for total bilirubin (TB), direct bilirubin (DB), and bile acids (BA) from the concentrations measured. MB represents the total amount (mg or mcMol) of a molecule removed from a solution and is the only representative parameter to verify the purification effectiveness of one system as it is not affected by the continuous production of the molecules, released in the circulation from the tissues, as it is the case for the reduction rate (RR). The total adsorption per hour is calculated by the ratio between MB and the time duration and shows the adsorption ability in an hour. Our comparative study shows the superior adsorption capability of CytoSorb system regarding TB, DB, and BA, evaluated through the MB and adsorption per hour, in comparison with CPFA, MARS, Prometheus, and PAP. In conclusion, as extracorporeal purification in liver failure could be considered useful for therapeutic purposes, Cytosorb, being more performing than other systems considered, could represent the device of first choice.

Pharmaceutical strategies for preventing toxicity and promoting antioxidant and anti-inflammatory actions of bilirubin

Bilirubin (BR) is the final product of haem catabolism. Disruptions along BR metabolic/transport pathways resulting from inherited disorders can increase plasma BR concentration (hyperbilirubinaemia). Unconjugated hyperbilirubinemia may induce BR accumulation in brain, potentially causing irreversible neurological damage, a condition known as BR encephalopathy or kernicterus, to which newborns are especially vulnerable. Numerous pharmaceutical strategies, mostly based on hemoperfusion, have been proposed over the last decades to identify new valid, low-risk alternatives for BR removal from plasma. On the other hand, accumulating evidence indicates that BR produces health benefits due to its potent antioxidant, anti-inflammatory and immunomodulatory action with a significant potential for the treatment of a multitude of diseases. The present manuscript reviews both such aspects of BR pharmacology, gathering literature data on applied pharmaceutical strategies adopted to: (i) reduce the plasma BR concentration for preventing neurotoxicity; (ii) produce a therapeutic effect based on BR efficacy in the treatment of many disorders.

Biological evaluation of a novel bilirubin adsorbent and its therapeutic effect on animal models of hyperbilirubinemia

Hyperbilirubinemia caused severe hepatobiliary diseases with various causes, especially hepatic fibrosis and cirrhosis caused by end-stage hepatitis B and C. Plasma adsorption perfusion (PP) has a tremendous advantage in treating patients with hyperbilirubinemia and liver failure, wherein, a safe and effective adsorbent is the key to filter out bilirubin successfully in PP. In this work, a simple engineering strategy, a new porous polymer adsorption resin ERM-0100 based on the homopolymer predispersion system, is proposed to produce high-performance bilirubin adsorbents. Preliminary experimental results show that ERM-0100 exhibits a large surface area and uniformly porous structure. Experimental results verify that ERM-0100 has high biocompatibility and bilirubin adsorption efficiency (TBIL:35%, direct bilirubin [DBIL]:30%, IBIL:87%) that is significantly higher than most of the reported adsorbents. Animal experiments prove that ERM-0100 has high bilirubin adsorption efficiency and can improve the liver function of animals. The combination of high biocompatibility and high adsorption capacity positions the ERM-0100 as a promising candidate for bilirubin removal.

Continuous renal replacement therapy and extended indications

Extracorporeal blood purification (EBP) techniques provide support for critically ill patients with single or multiple organ dysfunction. Continuous renal replacement therapy (CRRT) is the modality of choice for kidney support for those patients and orchestrates the interactions between the different artificial organ support systems. Intensive care teams should be familiar with the concept of sequential extracorporeal therapy and plan on how to incorporate new treatment modalities into their daily practices. Importantly, scientific evidence should guide the decision-making process at the bedside and provide robust arguments to justify the costs of implementing new EBP treatments. In this narrative review, we explore the extended indications for CRRT as an adjunctive treatment to provide support for the heart, lung, liver, and immune system. We detail practicalities on how to run the treatments and how to tackle the most frequent complications regarding each of the therapies, whether applied alone or integrated. The physicochemical processes and technologies involved at the molecular level encompassing the interactions between the molecules, membranes, and resins are spotlighted. A clinical case will illustrate the timing for the initiation, maintenance, and discontinuation of EBP techniques.

Bilirubin adsorption for the treatment of severe hyperbilirubinemia after cardiac surgery: A retrospective cohort study

OBJECTIVE

Severe hyperbilirubinemia after cardiac surgery increases in-hospital and 1-year mortality. Our present study aimed to analyze the safety and efficacy of bilirubin adsorption (BA) in patients with post-cardiac-surgery severe hyperbilirubinemia.

METHODS

We retrospectively included patients who underwent BA due to severe hyperbilirubinemia after cardiac surgery in our center between January 2015 and December 2018. The change of serum bilirubin, alanine aminotransferase, aspartate aminotransferase, and 30-day and 1-year mortality were assessed as endpoints. Univariate and multivariate analyses were employed to identify the risk factors of patient 30-day mortality.

RESULT

A total of 25 patients with 44 BA treatments were included. One BA treatment reduced total bilirubin (TB) concentration from 431.65 ± 136.34 to 324.83 ± 129.44 µmol/L (p < 0.001), with a reduction rate of 24.8%. No clinically relevant thrombosis of the extracorporeal circuit occurred during the BA treatment. The 30-day and 1-year mortality rates were 68% (n = 18) and 84% (n = 21), respectively. Multivariate analysis identified that TB level before BA treatment (odds ratio [OR] 1.010, 95% confidence interval [CI] 1.000-1.019; p = 0.043) was an independent risk factor of 30-day mortality.

CONCLUSIONS

BA treatment should be considered as an effective and safe method for the reduction of serum bilirubin in patients with post-cardiac-surgery severe hyperbilirubinemia. Patients with higher TB level before BA treatment had a relatively increased risk of 30-day mortality. Further studies are needed to evaluate the timing of BA for severe hyperbilirubinemia after cardiac surgery.

Artificial liver support systems: what is new over the last decade?

The liver is a complex organ that performs vital functions of synthesis, heat production, detoxification and regulation; its failure carries a highly critical risk. At the end of the last century, some artificial liver devices began to develop with the aim of being used as supportive therapy until liver transplantation (bridge-to-transplant) or liver regeneration (bridge-to-recovery). The well-recognized devices are the Molecular Adsorbent Recirculating System™ (MARS™), the Single-Pass Albumin Dialysis system and the Fractionated Plasma Separation and Adsorption system (Prometheus™). In the following years, experimental works and early clinical applications were reported, and to date, many thousands of patients have already been treated with these devices. The ability of artificial liver support systems to replace the liver detoxification function, at least partially, has been proven, and the correction of various biochemical parameters has been demonstrated. However, the complex tasks of regulation and synthesis must be addressed through the use of bioartificial systems, which still face several developmental problems and very high production costs. Moreover, clinical data on improved survival are conflicting. This paper reviews the progress achieved and new data published on artificial liver support systems over the past decade and the prospects for these devices.