[Artificial liver support systems: update on albumin dialysis (MARS)]

Crosslinked Bifunctional Particles for the Removal of Bilirubin in Hyperbilirubinemia Cases

This work describes the development of styrene-divinylbenzene (St-DVB) particles with polyethylene glycol methacrylate (PEGMA) and/or glycidyl methacrylate (GMA) brushes for the removal of bilirubin from blood in haemodialyzed patients. Bovine serum albumin (BSA) was immobilized onto the particles using ethyl lactate as a biocompatible solvent, which allowed the immobilization of up to 2 mg BSA/g of particles. The presence of albumin on the particles increased their capacity for bilirubin removal from phosphate-buffered saline (PBS) by 43% compared to particles without albumin. The particles were tested in plasma, finding that St-DVB-GMA-PEGMA particles that had been wetted in ethyl lactate with BSA reduced the concentration of bilirubin in plasma by 53% in less than 30 min. This effect was not observed in particles without BSA. Therefore, the presence of albumin on the particles enabled quick and selective removal of bilirubin from plasma. Overall, the study highlights the potential use of St-DVB particles with PEGMA and/or GMA brushes for bilirubin removal in haemodialyzed patients. The immobilization of albumin onto the particles using ethyl lactate increased their capacity for bilirubin removal and enabled quick and selective removal from plasma.

Development of an automated liver perfusion system: The benefit of a hemofilter

Introduction:

Liver perfusion machines are close to becoming a reality in the transplantation field. However, depending on the techniques used and the goals pursued, their application is limited in the research field. Here, we present the entire development of a perfusion system with self-made engineering, completely autonomous controls, and a high degree of versatility that allows the design of different studies on liver functionality.

Methods:

A user-friendly interface permits real-time monitoring and remote control by the devices within the circuit. Centrifugal pumps allow the perfusate enter the organ with controlled pressures and flows at both hepatic artery and portal vein. The implementation of a hemofilter as a novel tool permits to control and maintain homeostasis. Peristaltic pumps adjust pH, extraction rate, and total volume by means of sensors.

Results:

Real-time monitoring facilitates liver functionality assessment. The controlled system shows rapid stabilization and quick responses to changes during 6 h of perfusion experiments. Furthermore, the integration of a hemofilter helps the system to eliminate toxic waste and maintain homeostasis.

Discussion:

The machine provides the basis of a perfusion system with autonomous controls and the implementation of a hemofilter that enables a more efficient control of hemostasis. Moreover, the developed hardware and software are subjected to further tuning for additional purposes such as pathophysiologic studies, suboptimal grafts recovery, or recellularization of decellularized scaffolds among others.

Clinical observation on the treatment of acute liver failure by combined non-biological artificial liver

The clinical efficacy and safety of different combinations of non-bio artificial liver in the treatment of acute liver failure was examined. A total of 61 cases were selected under blood purification treatment from the patients with severe acute liver failure admitted to the severe disease department of the hospital from December, 2010 to December, 2015. Three types of artificial liver combinations were observed, i.e., plasma exchange plus hemoperfusion plus continuous venovenous hemodiafiltration (PE+HP+CVVHDF), PE+CVVHDF and HP+CVVHDF. The heart rate (HR), mean arterial pressure (MAP), respiratory index (PaO₂/FiO₂), liver and kidney function indicator, as well as platelet and coagulation function were compared. A comparison before and after the treatment using the three methods, showed improvement in the HRs, MAPs, PaO₂/FiO₂, total bilirubins (TBIL) and alanine aminotransferases (ALT) (P<0.05), of which TBIL and ALT were decreased more significantly (P<0.01) in the PE+CVVHDF and PE+HP+CVVHDF groups. Only changes in the PE+HP+CVVHDF and PE+CVVHDF groups were statistically significant after prothrombin time and albumin treatment (P<0.05). The difference between the decrease in TBIL in the PE+HP+CVVHDF group and that in the HP+CVVHDF group was statistically significant (P<0.05). Treatment of the 61 patients using the artificial liver support system yielded a survival rate of 62.3% (38/61), and a viral survival rate of 35.0% (7/20); with the non-viral survival rate being 75.6% (31/41). In conclusion, following the treatment of three types of artificial livers, the function was improved to varying degrees, with the PE+HP+CVVHDF and the PE+CVVHDF method being better. By contrast, after the treatment of non-viral liver failure, the survival rate was significantly higher than the patients with viral liver failure.

[Acute on chronic liver failure]

Acute-on-Chronic Liver Failure (ACLF) is a recently introduced term defined as severe acute deterioration of an established liver disease. This entity usually develops after an acute insult. The main clinical manifestations are hepatorenal syndrome, hepatic encephalopathy and organ failure, with a high risk of death in the short term. The true incidence of ACLF remains difficult to determine due to confusions surrounding the definition of this entity, but seems to be 40% at 5 years in patients with advanced cirrhosis, which translates into 4,000 cases in Europe within this time span. The treatment of choice is liver transplantation. However, due to the shortage of suitable organs and morbidity and mortality in these patients, other options must be used.