The effect of molecular adsorbent recirculating system treatment on survival, native liver recovery, and need for liver transplantation in acute liver failure patients

Liver-Support Therapies in Critical Illness-A Comparative Analysis of Procedural Characteristics and Safety

Extracorporeal liver-support therapies remain controversial in critically ill patients, as most studies have failed to show an improvement in outcomes. However, heterogeneous timing and inclusion criteria, an insufficient number of treatments, and the lack of a situation-dependent selection of available liver-support modalities may have contributed to negative study results. We retrospectively investigated the procedural characteristics and safety of the three liver-support therapies CytoSorb, Molecular Adsorbent Recirculating System (MARS) and therapeutic plasma exchange (TPE). Whereas TPE had its strengths in a shorter treatment duration, in clearing larger molecules, affecting platelet numbers less, and improving systemic coagulation and hemodynamics, CytoSorb and MARS were associated with a superior reduction in particularly small protein-bound and water-soluble substances. The clearance magnitude was concentration-dependent for all three therapies, but additionally related to the molecular weight for CytoSorb and MARS therapy. Severe complications did not appear. In conclusion, a better characterization of disease-driving as well as beneficial molecules in critically ill patients with acute liver dysfunction is crucial to improve the use of liver-support therapy in critically ill patients. TPE may be beneficial in patients at high risk for bleeding complications and impaired liver synthesis and hemodynamics, while CytoSorb and MARS may be considered for patients in whom the elimination of smaller toxic compounds is a primary objective.

Artificial liver support in patients with liver failure: a modified DELPHI consensus of international experts

The present narrative review on albumin dialysis provides evidence-based and expert opinion guidelines for clinicians caring for adult patients with different types of liver failure. The review was prepared by an expert panel of 13 members with liver and ntensive care expertise in extracorporeal liver support therapies for the management of patients with liver failure. The coordinating committee developed the questions according to their importance in the management of patients with liver failure. For each indication, experts conducted a comprehensive review of the literature aiming to identify the best available evidence and assessed the quality of evidence based on the literature and their experience. Summary statements and expert's recommendations covered all indications of albumin dialysis therapy in patients with liver failure, timing and intensity of treatment, efficacy, technical issues related to the device and safety. The panel supports the data from the literature that albumin dialysis showed a beneficial effect on hepatic encephalopathy, refractory pruritus, renal function, reduction of cholestasis and jaundice. However, the trials lacked to show a clear beneficial effect on overall survival. A short-term survival benefit at 15 and 21 days respectively in acute and acute-on-chronic liver failure has been reported in recent studies. The technique should be limited to patients with a transplant project, to centers experienced in the management of advanced liver disease. The use of extracorporeal albumin dialysis could be beneficial in selected patients with advanced liver diseases listed for transplant or with a transplant project. Waiting future large randomized controlled trials, this panel experts' statements may help careful patient selection and better treatment modalities.

MARS: Should I Use It?

Severe liver failure, including acute liver failure and acute-on-chronic liver failure, is associated with high mortality, and many patients die despite aggressive medical therapy. While liver transplantation is a viable treatment option for liver failure patients, a large proportion of these patients die given the shortage in the liver donation and the severity of illness, leading to death while waiting for a liver transplant. Extracorporeal liver support devices, including molecular adsorbent recirculating system (MARS), have been developed as bridge to transplantation (bridge for patients who are decompensating while waiting for liver transplantation) and bridge to recovery (for whom recovery is deemed reasonable). In addition to its uses in acute liver failure and acute-on-chronic liver failure, the MARS system has also been applied in various clinical settings, such as drug overdosing and poisoning and intractable cholestatic pruritus refractory to pharmacological treatment. This review aims to discuss the controversies, potential benefits, practicalities, and disadvantages of using MARS in clinical practice.

Outcome of patients treated with molecular adsorbent recirculating system albumin dialysis: A national multicenter study

Background and Aim

The molecular adsorbent recirculating system (MARS) is the most widely used device to treat liver failure. Nevertheless, data from widespread real‐life use are lacking.

Methods

This was a retrospective multicenter study conducted in all French adult care centers that used MARS between 2004 and 2009. The primary objective was to evaluate patient survival according to the liver disease and listing status. Factors associated with mortality were the secondary objectives.

Results

A total of 383 patients underwent 393 MARS treatments. The main indications were acute liver failure (ALF, 32.6%), and severe cholestasis (total bilirubin >340 μmol/L) (37.2%), hepatic encephalopathy (23.7%), and/or acute kidney injury–hepatorenal syndrome (22.9%) most often among patients with chronic liver disease. At the time of treatment, 34.4% of the patients were listed. Overall, the hospital survival rate was 49% (95% CI: 44–54%) and ranged from 25% to 81% depending on the diagnosis of the liver disease. In listed patients versus those not listed, the 1‐year survival rate was markedly better in the setting of nonbiliary cirrhosis (59% vs 15%), early graft nonfunction (80% vs 0%), and late graft dysfunction (72% vs 0%) (all P < 0.001). Among nonbiliary cirrhotic patients, hospital mortality was associated with the severity of liver disease (HE and severe cholestasis) and not being listed for transplant. In ALF, paracetamol etiology and ≥3 MARS sessions were associated with better transplant‐free survival.

Conclusion

Our study suggests that MARS should be mainly used as a bridge to liver transplantation. Survival was correlated with being listed for most etiologies and with the intensity of treatment in ALF.

Adolescent With Acute Liver Failure in the Setting of Ethanol, Cocaine, and Ecstasy Ingestion Treated With a Molecular Adsorbent Recirculating System

Recreational polypharmacy intoxication is a popular trend, particularly among adolescents and young adults. Acute liver failure is an uncommon complication of drug intoxication and has been described separately among patients intoxicated with ethanol, cocaine, and 3,4-methylenedioxy-methamphetamine (MDMA, ecstasy). Many patients with acute liver failure will die without liver transplant, and management of drug-induced acute liver failure is complicated by the fact that polysubstance abuse may be a contraindication for liver transplant, even among young patients.

Here we report a case of acute liver failure in an adolescent male secondary to recreational intoxication with ethanol, cocaine, and ecstasy. This patient was not a candidate for liver transplantation. We describe successful treatment using a molecular adsorbent recirculating system (MARS®) or “liver dialysis” and review the literature pertaining to management options for this type of patient.

The role of living donor liver transplantation for acute liver failure

Acute liver failure (ALF) is a life-threatening illness that occurs in the absence of pre-existing liver disease. When symptoms seriously progress under continuous supportive medical care, liver transplantation becomes the only therapeutic strategy. However, the available sources of organs for liver transplantation differ worldwide. In regions in which organs from cadaveric donors are more common, deceased donor liver transplantation (DDLT) is performed in this urgent situation. Conversely, in countries where cadaveric donors are scarce, living donor liver transplantation (LDLT) is the only choice. Special considerations must be made for urgent LDLT for ALF, including the expedited evaluation of living donors, technical issues, and the limitations of ABO blood type combinations between recipients and donor candidates. In this review, we highlight the role of LDLT for ALF and the considerations that distinguish it from DDLT. LDLT is well-established as a life-saving procedure for ALF patients and there is often no alternative to LDLT, especially in countries where DDLT is not feasible. However, from a global perspective, an increase in the deceased donor pool might be an urgent and important necessity.

Acute Fatty Liver of Pregnancy: Pathophysiology, Anesthetic Implications, and Obstetrical Management

A narrative review of the pathophysiology, diagnosis, management, delivery implications, obstetric anesthesia care, and potential critical care needs in patients presenting with acute fatty liver of pregnancy.

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.

Nonacetaminophen Drug-Induced Acute Liver Failure

Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival.

Increased acetaminophen related calls to Finnish PIC better reflect acetaminophen sales than serious poisonings

OBJECTIVE

Acetaminophen (APAP) or paracetamol is a commonly encountered medicine in poisonings. We studied the changes in APAP related calls to the Finnish poison information centre (FPIC), and serious intoxications, involving hepatotoxicity or death in 2001-2014. These data were compared with paracetamol sales in Finland.

METHODS

This is a retrospective analysis of the FPIC database calls, national cause of death registry, registries of liver transplantations and molecular adsorbent recycling system (MARS)-treated patients from Helsinki University Hospital together with the National Institute of Health and Welfare registry of patients hospitalized. Data on APAP sales were obtained from the Finnish Medicines Agency.

RESULTS

Between 2001 and 2014, the number of calls/year related to human APAP exposures to the FPIC increased from 227 to 1058. No change in the age distribution of enquiries was seen. Most calls involved minors: 58% (range 52-64%) for children under 6 years old, and 9% (range 6-14%) for children of 6-15 years. In Finland, APAP related fatalities have gradually increased from an average of 7/year (range 4-10) in 2000-2005 to an average of 11/year (range 6-17) in 2010-2013, whereas the number of liver transplantations remained low, average 0.6/year (range 0-2). For patients in need of MARS-treatment, a slight decrease was seen. Total APAP sales increased from 5.6 (47% prescription, 53% OTC) to 29.7 (81% prescription, 19% OTC). DDD/1000 inhabitants/day from 2001 to 2014 is recorded. Best linear relationship (R² = 0.97; p < .001) was observed between total FPIC calls and total sales of APAP in 2001-2014. Fatalities show a weaker relationship with sales (R² = 0.317; p = .045).

CONCLUSIONS

During the study period, we see an increase in FPIC exposure calls accompanied by an increase in APAP sales. Changes in the chosen indicators for serious poisonings show only a weak association. Despite an evident trend between sales and fatalities, the correlation with fatality remains weak due to the small number of fatalities.

EASL Clinical Practical Guidelines on the management of acute (fulminant) liver failure

The term acute liver failure (ALF) is frequently applied as a generic expression to describe patients presenting with or developing an acute episode of liver dysfunction. In the context of hepatological practice, however, ALF refers to a highly specific and rare syndrome, characterised by an acute abnormality of liver blood tests in an individual without underlying chronic liver disease. The disease process is associated with development of a coagulopathy of liver aetiology, and clinically apparent altered level of consciousness due to hepatic encephalopathy. Several important measures are immediately necessary when the patient presents for medical attention. These, as well as additional clinical procedures will be the subject of these clinical practice guidelines.

Molecular adsorbent recirculating system (MARS) in acute liver injury and graft dysfunction: Results from a case-control study

Background

The primary therapeutic goals in the treatment of liver injury are to support liver regeneration or bridge the gap to liver transplantation (LT). Molecular adsorbent recirculating system (MARS) therapy has shown beneficial effects for specific symptoms of liver failure; however, general survival advantages have not yet been demonstrated.

Aim

We studied the effects of MARS therapy compared to standard medical treatment (SMT) in two patient cohorts: in patients with an acute liver injury and in those with graft dysfunction (GD).

Methods

We report on our experience over a 6.5-year period with 73 patients treated with SMT or with SMT and MARS (MARS group). In total, 53 patients suffered from acute liver injury in their native liver without a preexisting liver disease (SMT: n = 31, MARS: n = 22), and 20 patients showed a severe GD after LT (SMT: n = 10, MARS: n = 10).

Results

The entire cohort was predominantly characterized by hemodynamically and respiratorily stable patients with a low hepatic encephalopathy (HE) grade and a model of end-stage liver disease (MELD) score of 20.57 (MARS) or 22.51 (SMT, p = 0.555). Within the MARS group, the median number of extracorporeal therapy sessions was four (range = 3–5 sessions). Independent of the underlying etiology, MARS improved the patients’ bilirubin values in the short term compared to SMT alone. In patients with acute liver injury, this response was sustained even after the end of MARS therapy. By contrast, the majority of patients with GD and an initial response to MARS therapy experienced worsened hyperbilirubinemia. No differences in 28-day mortality were observed with respect to acute liver injury (MARS 5.3% (95% CI: 0–15.3); SMT 3.3% (95% CI: 0–9.8), p = 0.754) or GD (MARS 20.0% (95% CI: 0–44.7), SMT 11.1% (95% CI: 0–31.7), p = 0.478).

Conclusions

Although it did not improve 28-day mortality, MARS therapy improved the short-term response in patients with acute liver injury as well as in those with GD. In cases of acute hepatic injury, the use of MARS therapy resulted in the sustained stabilization of liver function and improved liver regeneration. A short-term response to MARS may predict the future course of the disease.

Drug-Induced Acute Liver Failure

Drug-induced acute liver failure (ALF) disproportionately affects women and nonwhites. It is most frequently caused by antimicrobials and to a lesser extent by complementary and alternative medications, antiepileptics, antimetabolites, nonsteroidals, and statins. Most drug-induced liver injury ALF patients have hepatocellular injury pattern. Cerebral edema and intracranial hypertension are the most serious complications of ALF. Other complications include coagulopathy, sepsis, metabolic derangements, and renal, circulatory, and respiratory dysfunction. Although advances in intensive care have improved outcome, ALF has significant mortality without liver transplantation. Liver-assist devices may provide a bridge to transplant or to spontaneous recovery.

Management of Acute Hepatotoxicity Including Medical Agents and Liver Support Systems

Drug-induced liver injury (DILI) can be predictable or idiosyncratic and has an estimated incidence of approximately 20 cases per 100,000 persons per year. DILI is a common cause of acute liver failure in the United States. No accurate tests for diagnosing DILI exist, and its diagnosis is based on exclusion of other conditions. Managing DILI includes discontinuing the suspected causative agent and in selected cases administering an antidote. Liver support systems are used for long-term support or as a bridge to transplantation and are effective for improving encephalopathy, hyperbilirubinemia, and other liver-related conditions, but whether they improve survival remains uncertain.

Impact of splenic artery ligation after major hepatectomy on liver function, regeneration and viability

It was reported that prevention of acute portal overpressure in small-for-size livers by inflow modulation results in a better postoperative outcome. The aim is to investigate the impact of portal blood flow reduction by splenic artery ligation after major hepatectomy in a murine model. Forty-eight rats were subjected to an 85% hepatectomy or 85% hepatectomy and splenic artery ligation. Both groups were evaluated at 24, 48, 72 and 120 post-operative hours: liver function, regeneration and viability. All methods and experiments were carried out in accordance with Coimbra University guidelines. Splenic artery ligation produces viability increase after 24 h, induces a relative decrease in oxidative stress during the first 48 hours, allows antioxidant capacity increment after 24 h, which is reflected in a decrease of half-time normalized liver curve at 48 h and at 72 h and in an increase of mitotic index between 48 h and 72 h. Splenic artery ligation combined with 85% hepatectomy in a murine model, allows portal inflow modulation, promoting an increase in hepatocellular viability and regeneration, without impairing the function, probably by inducing a less marked elevation of oxidative stress at first 48 hours.

Extracorporeal continuous portal diversion plus temporal plasmapheresis for “small-for-size” syndrome

AIM: To investigate the effect of plasmapheresis via the portal vein for “small-for-size” syndrome (SFSS) aided by extracorporeal continuous portal diversion (ECPD).

METHODS: Extensive or total hepatectomy in the pig is usually adopted as a postoperative liver failure (PLF) or SFSS model. In this study, animals which underwent 85%-90% hepatectomy were randomized into either the Systemic group (n = 7) or the Portal group (n = 7). In the Systemic group, all pigs received temporal plasmapheresis (PP) via the extracorporeal catheter circuit (systemic to systemic circulation) from 24 to 30 h post-hepatectomy (PH); in the Portal group, all pigs received ECPD to divert partial portal vein flow (PVF) to the systemic circulation after hepatectomy, then converted to temporal PP from 24 to 30 h PH, and subsequently converted to ECPD again until 48 h PH. In the Portal group, the PVF was preserved at 3.0-3.3 times that of the baseline value, similar to that following 70% hepatectomy, which was regarded as the optimal PVF to the hypertrophic liver remnant. At 48 h PH, all pigs were re-opened and the portal vein pressure (PVP), PVF, and HAF (hepatic artery flow) were measured, and then diversion of the portal venous flow was terminated. After 1 h the PVP, PVF, and HAF were re-measured. The portal hemodynamic changes, liver injury, liver regeneration and bacterial/lipopolysaccharide (LPS) translocation were evaluated in the two groups.

RESULTS: The PVP in the Portal group was significantly lower than that in the Systemic group during the time period from 2 to 49 h PH (P < 0.05). Serum alanine aminotransferase (ALT), total bilirubin (TB) and ammonia were significantly reduced in the Portal group compared with the Systemic group from 24 to 48 h PH (P < 0.05). The Portal group may have attenuated sinusoidal endothelial injury and decreased the level of HA compared with the Systemic group. In the Systemic group, there was significant sinusoidal dilation, hydropic changes in hepatocytes and hemorrhage into the hepatic parenchyma, and the sinusoidal endothelial lining was partially destroyed and detached into the sinusoidal space. CD₃₁ immunostaining revealed significant destruction of the endothelial lining. In the Portal group, there was no intraparenchymal hemorrhage and the sinusoidal endothelial cells and hepatocytes were well preserved. CD₃₁ immunostaining was mild which indicated less destruction of the endothelial lining. HA was significantly decreased in the Portal group compared with the Systemic group from 2 to 48 h PH. The rate of liver remnant regeneration was elevated, while apoptosis was attenuated in the Portal group compared with the Systemic group. Thymidine kinase activity was much higher in the Portal group than in the Systemic group at 48 h PH. The PCNA index was significantly increased and the apoptotic index was significantly decreased in the Portal group compared with the Systemic group. Bacterial translocation and endotoxin, as well as the inflammatory response, were significantly attenuated in the Portal group compared with the Systemic group. LPS, tumor necrosis factor-α and interleukin-6 levels were all significantly decreased in the Portal group compared with the Systemic group from 24 to 48 h PH, while bacterial DNA level was significantly decreased from 2 to 48 h PH.

CONCLUSION: PP plus ECPD via the portal vein can attenuate toxic load and hyperperfusion injury, and should be undertaken instead of PP via the systemic circulation in SFSS or PLF.

Impact of molecular adsorbent recirculating system on renal recovery in type-1 hepatorenal syndrome patients with chronic liver failure

BACKGROUND AND AIM

Liver transplantation remains the best option for treating type-1 hepatorenal syndrome (HRS1). The aim of this retrospective study was to determine whether the molecular adsorbent recirculation system (MARS) can improve renal function in HRS1 patients.

METHODS

Thirty-two patients with chronic liver disease and HRS1 were treated by MARS sessions which were performed every other day. The endpoint was renal function improvement by 28 days after diagnosis of HRS1 that was defined as a serum-creatinine level of < 133 μmol/L. Partial renal recovery was defined as a 10% decrease in baseline serum-creatinine level.

RESULTS

The mean number of MARS sessions required by each patient was 3.5 ± 1.5. The median time between admission and the start of MARS therapy was 3 (0-15) days. Of the total patients, 13 (40%) had improved renal function. Among these, nine (28%) had complete renal recovery. Among the patients that survived, only 40% (6/15) had improved renal function, and among the patients that died within the first month after the initiation of MARS, seven patients had a renal response. The 28-day survival rate was 47%. Seven patients received a liver transplant after diagnosis of HRS. Of these, four had complete or partial recovery after transplantation (57%) versus 9 of the 25 patients who did not undergo liver transplantation (36%), P = not significant.

CONCLUSION

MARS therapy improved renal function in only very few patients with HRS1. Further controlled studies including large number of patients are required.

Use of the molecular adsorbent recirculating system (MARS™) for the management of acute poisoning with or without liver failure

INTRODUCTION

There is an increasing interest in recent developments in bioartificial and non-bioartificial devices, so called extracorporeal liver assist devices, which are now used widely not only to increase drug elimination, but also to enhance the removal of endogenous substances in acute liver failure. Most of the non-bioartificial techniques are based on the principle of albumin dialysis. The objective is to remove albumin-bound substances that could play a role in the pathophysiology of acute liver failure by dialysing blood against an albumin-containing solution across a high flux permeable membrane. The most widely used device is the Molecular Adsorbent Recirculating System (MARS™).

METHODS

The relevant English and French literature was identified through Medline using the terms, 'molecular adsorbent recirculating system', 'MARS', 'acute liver failure', 'acute poisoning', 'intoxication'. This search identified 139 papers of which 48 reported on a toxic cause for the use of MARS™. Of these 48 papers, 39 specified the substance (eighteen different substances were identified); two papers reported on the same group of patients. BIOARTIFICIAL AND NON-BIOARTIFICIAL SYSTEMS: Bioartificial systems based on porcine hepatocytes incorporated in the extracorporeal circuit are no longer in use due to the possibility of porcine retroviral transmission to humans. Historically, experience with such devices was limited to a few cases of paracetamol poisoning. In contrast, an abundant literature exists for the non-bioartificial systems based on albumin dialysis. The MARS™ has been used more widely than other techniques, such as the one using fractionated plasma separation and adsorption (Prometheus™). All the extracorporeal liver assist devices are able to some extent to remove biological substances (ammonia, urea, creatinine, bilirubin, bile acids, amino acids, cytokines, vasoactive agents) but the real impact on the patient's clinical course has still to be determined. Improvement in cardiovascular or neurological dysfunction has been shown both in acute liver failure and acute-on-chronic liver failure but no impact on mortality has been reported. ACUTE POISONING WITH LIVER FAILURE: Randomized controlled trials are very limited in number and patients poisoned by paracetamol or Amanita phalloides are usually included for outcome analysis in larger groups of acute liver failure patients. Initial results look promising but should be confirmed. Beyond its effect in liver failure, MARS™ could also enhance the elimination of the drug or toxin responsible for the failure, as is described with paracetamol. ACUTE POISONING WITHOUT LIVER FAILURE: Extracorporeal liver assist devices have also been used to promote elimination of drugs that are highly protein bound. Data in various case reports confirm a high elimination of phenytoin, theophylline and diltiazem. However, definite conclusions on the toxicokinetic or clinical efficacy cannot be drawn.

CONCLUSIONS

Despite the lack of large multicentre randomized trials on the use of MARS™ in patients with acute liver failure, the literature shows clinical and biological benefit from this technique. In drug or toxin-induced acute liver failure, such as paracetamol or mushroom poisoning, MARS™ has been used extensively, confirming in a non-randomized fashion, the positive effect observed in the larger population of acute liver failure patients. Furthermore, as MARS™ has been shown in experimental studies to remove protein-bound substances, it is potentially a promising treatment for patients with acute poisoning from drugs that have high protein-binding capacity and are metabolized by the liver, especially, if they develop liver failure concomitantly.

Neurological complications of acute liver failure: pathophysiological basis of current management and emerging therapies

One of the major causes of mortality in patients with acute liver failure (ALF) is the development of hepatic encephalopathy (HE) which is associated with increased intracranial pressure (ICP). High ammonia levels, increased cerebral blood flow and increased inflammatory response have been identified as major contributors to the development of HE and the related brain swelling. The general principles of the management of patients with ALF are straightforward. They include identifying the insult causing hepatic injury, providing organ systems support to optimize the patient's physical condition, anticipation and prevention of development of complications. Increasing insights into the pathophysiological mechanisms of ALF are contributing to better therapies. For instance, the evident role of cerebral hyperemia in the pathogenesis of increased ICP has led to a re-evaluation of established therapies such as hyperventilation, N-acetylcysteine, thiopentone sodium and propofol. The role of systemic inflammatory response in the pathogenesis of increased ICP has also gained importance supporting the concept that antibiotics given prophylactically reduce the risk of developing sepsis during the course of illness. Moderate hypothermia has also been established as a therapy able to reduce ICP in patients with uncontrolled intracranial hypertension and to prevent increases in ICP during orthopic liver transplantation. Ornithine phenylacetate, a new drug in the treatment of liver failure, and liver replacement therapies are still being investigated both experimentally and clinically. Despite many advances in the understanding of the pathophysiological basis and the management of intracranial hypertension in ALF, more clinical trials should be conducted to determine the best therapeutic management for this difficult clinical event.

Extracorporeal liver support with multipass albumin dialysis or plasmapheresis and filtering systems in acute liver failure

Acute liver failure is a very complex type of disease with a mortality of up to 90%, leading to numerous severe disturbances of the whole organism. Bleeding because of absent synthesis of various coagulation factors and disseminated intravascular coagulation, acute kidney failure, circulatory failure with vasopressor dependence, respiratory failure with adult respiratory distress syndrome, neurological failure up to coma because of hepatic encephalopathy, and a very high risk of infection and sepsis frequently result from the initial state of isolated liver failure. High urgency liver transplantation is a highly efficient therapy if performed in time. However, increasing the rate of spontaneous recovery of the patients' own liver, and reducing the need for liver transplantation is preferable and would further improve the outcome of acute liver failure. Extracorporeal liver support by multipass albumin dialysis or plasmapheresis and filtering systems may offer a possibility to fulfill these aims of therapy. A prospective study in 88 patients with acute liver failure has shown a nonsignificant trend in improvement of survival after acute liver failure by multipass albumin dialysis and filtering. Other retrospective studies have shown benefits in improving hepatic encephalopathy and brain oedema. Further, an increase in the rate of spontaneous recovery of liver function has been described. With regional citrate anticoagulation for multipass albumin dialysis and filtering, the need for systemic anticoagulation - a potentially very harmful measure in these patients - can be eliminated and the rate of filter clotting can extremely effectively be reduced.

Bridging Therapies and Liver Transplantation in Acute Liver Failure; 10 Years of MARS Experience from Finland

Acute liver failure is a life-threatening condition in the absence of liver transplantation option. The aetiology of liver failure is the most important factor determining the probability of native liver recovery and prognosis of the patient. Extracorporeal liver assist devices like MARS (Molecular Adsorbent Recirculating System) may buy time for native liver recovery or serve as bridging therapy to liver transplantation, with reduced risk of cerebral complications. MARS treatment may alleviate hepatic encephalopathy even in patients with a completely necrotic liver. Taking this into account, better prognostic markers than hepatic encephalopathy should be used to assess the need for liver transplantation in acute liver failure.

[Intensive care of patients with acute liver failure]

BACKGROUND

Acute liver failure and acute decompensated chronic liver failure are two diseases that demand extensive knowledge of etiology and triggering factors, pathophysiology, diagnosis, prognosis and recommended guidelines for treatment. The article defines the diseases, discusses etiological factors, treatment strategies, indications for referral to the transplantation unit at Rikshospitalet and prognostic factors of importance.

MATERIAL AND METHODS

The basis for this article is literature identified through a non-systematic search in PubMed and the authors' clinical experience and experimental research within the field.

RESULTS

In the Western world paracetamol poisoning and toxic reactions to other drugs are the most common triggering factors for acute liver poisoning in adults. Patients can quickly develop multi organ failure requiring advanced intensive care. The most common complications are hepatic encephalopathy, acute renal failure and coagulation disturbances. Acute decompensated chronic liver failure strikes patients with known liver disease and is most often triggered by inflammation, infection, gastrointestinal bleeding, drugs, traumas or disturbances in acid/base/electrolyte balance. Early diagnosing of triggering factors and intensive medical supportive treatment is especially important. Acute renal failure indicates a very bad prognosis.

INTERPRETATION

Patients diagnosed with acute liver failure or acute decompensated chronic liver failure remain a clinical challenge. Optimal treatment requires extensive knowledge of pathophysiological mechanisms and treatment strategies.

Cost-utility of molecular adsorbent recirculating system treatment in acute liver failure

AIM: To determine the short-term cost-utility of molecular adsorbent recirculating system (MARS) treatment in acute liver failure (ALF).

METHODS: A controlled retrospective study was conducted with 90 ALF patients treated with MARS from 2001 to 2005. Comparisons were made with a historical control group of 17 ALF patients treated from 2000 to 2001 in the same intensive care unit (ICU) specializing in liver diseases. The 3-year outcomes and number of liver transplantations were recorded. All direct liver disease-related medical expenses from 6 mo before to 3 years after ICU treatment were determined for 31 MARS patients and 16 control patients. The health-related quality of life (HRQoL) before MARS treatment was estimated by a panel of ICU doctors and after MARS using a mailed 15D (15-dimensional generic health-related quality of life instrument) questionnaire. The HRQoL, cost, and survival data were combined and the incremental cost/quality-adjusted life years (QALYs) was calculated.

RESULTS: In surviving ALF patients, the health-related quality of life after treatmeant was generally high and comparable to the age- and gender-matched general Finnish population. Compared to the controls, the average cost per QALY was considerably lower in the MARS group (64 732€vs 133 858€) within a timeframe of 3.5 years. The incremental cost of standard medical treatment alone compared to MARS was 10 928€, and the incremental number of QALYs gained by MARS was 0.66.

CONCLUSION: MARS treatment combined with standard medical treatment for ALF in an ICU setting is more cost-effective than standard medical treatment alone.

Critical care organ support: a focus on extracorporeal systems

PURPOSE OF REVIEW

An extensive search of the literature published in the past 2 years related to critical care organ support was undertaken. This review is limited to those that focus on extracorporeal life support modalities for adults.

RECENT FINDINGS

Traditional indications for extracorporeal life support such as oxygenation, carbon dioxide exchange and support of perfusion have expanded to include solute and toxin clearance for kidney, liver and potentially neurological failure. Enhanced understanding of cell-mediated mechanisms of injury may explain multiple-organ dysfunction following single-organ damage. Extracorporeal life support systems can be used safely in patients with traumatic brain, chest, and abdominal injury. 'Emergency perfusion and resuscitation' following traumatic exsanguination is entering clinical trials.

SUMMARY

Multiple-organ dysfunction followed by traumatic injury can be treated with multiple-organ support. A total extracorporeal organ support system may be used in the future as a portable, bedside organ support device.

Albumin dialysis in liver failure: comparison of molecular adsorbent recirculating system and single pass albumin dialysis--a retrospective analysis

Despite improvement in critical care, liver failure is still associated with high mortality. Therapeutic concepts are aimed at restoring endogenous liver function or to bridge the time to liver transplantation. In addition to standard medical treatment, extracorporeal liver support with albumin dialysis is used for this purpose. The aim of this study was to analyze the efficacy of single pass albumin dialysis (SPAD) in comparison to the molecular adsorbent recirculating system (MARS) in patients treated at our university hospital intensive care unit between July 2004 and August 2008. In this retrospective analysis we studied patients presenting with liver failure who were treated with albumin dialysis. Laboratory parameters, daily health scoring, the number of transfusions, and mortality were recorded. The (paired) t-test, Mann-Whitney U-test, and Wilcoxon test were used for statistical analysis. In all, 163 albumin dialysis treatments, 126 with MARS and 37 with SPAD, in 57 patients were performed. MARS resulted in a significant decrease in bilirubin (-38 +/- 66.5 micromol/L from a baseline of 301 +/- 154.6 micromol/L), gamma-glutamyltransferase (gamma-GT), alanine aminotransferase, creatinine, and urea. SPAD resulted in a significant decrease in bilirubin (-41 +/- 111.2 micromol/L from a baseline of 354 +/- 189.4 micromol/L) and gamma-GT, while lactate levels increased. No differences in the need for blood transfusion, health scoring, or mortality between the two treatment modalities were detected. This retrospective analysis suggests equal efficacy of MARS and SPAD; however, prospective assessment to further define the role of SPAD in the treatment of acute or acute-on-chronic liver failure is needed.

Early molecular adsorbents recirculating system treatment of Amanita mushroom poisoning

Acute poisoning due to ingestion of hepatotoxic Amanita sp. mushrooms can result in a spectrum of symptoms, from mild gastrointestinal discomfort to life-threatening acute liver failure. With conventional treatment, Amanita phalloides mushroom poisoning carries a substantial risk of mortality and many patients require liver transplantation. The molecular adsorbent recirculating system (MARS) is an artificial liver support system that can partly compensate for the detoxifying function of the liver by removing albumin-bound and water-soluble toxins from blood. This treatment has been used in acute liver failure to enable native liver recovery and as a bridging treatment to liver transplantation. The aim of the study is to evaluate the outcome of 10 patients with Amanita mushroom poisoning who were treated with MARS. The study was a retrospectively analyzed case series. Ten adult patients with accidental Amanita poisoning of varying severity were treated in a liver disease specialized intensive care unit from 2001 to 2007. All patients received MARS treatment and standard medical therapy for mushroom poisoning. The demographic, laboratory, and clinical data from each patient were recorded upon admission. The one-year survival and need for liver transplantation were documented. The median times from mushroom ingestion to first-aid at a local hospital and to MARS treatment were 18 h (range 14-36 h) and 48 h (range 26-78 h), respectively. All 10 patients survived longer than one year. One patient underwent a successful liver transplantation. No serious adverse side-effects were observed with the MARS treatment. In conclusion, MARS treatment seems to offer a safe and effective treatment option in Amanita mushroom poisoning.

Survival predictors in patients treated with a molecular adsorbent recirculating system

AIM: To identify prognostic factors for survival in patients with liver failure treated with a molecular adsorbent recirculating system (MARS).

METHODS: MARS is a liver-assisting device that has been used in the treatment of liver failure to enable native liver recovery, and as a bridge to liver transplantation (LTX). We analyzed the 1-year outcomes of 188 patients treated with MARS, from 2001 to 2007, in an intensive care unit specializing in liver disease. Demographic, clinical and laboratory parameters were recorded before and after each treatment. One-year survival and the number of LTXs were recorded. Logistic regression analysis was performed to determine factors predicting survival.

RESULTS: The study included 113 patients with acute liver failure (ALF), 62 with acute-on-chronic liver failure (AOCLF), 11 with graft failure (GF), and six with miscellaneous liver failure. LTX was performed for 29% of patients with ALF, 18% with AOCLF and 55% with GF. The overall 1-year survival rate was 74% for ALF, 27% for AOCLF, and 73% for GF. The poorest survival rate, 6%, was noted in non-transplanted patients with alcohol-related AOCLF and cirrhosis, whereas, patients with enlarged and steatotic liver had 55% survival. The etiology of liver failure was the most important predictor of survival (P < 0.0001). Other prognostic factors were encephalopathy (P = 0.001) in paracetamol-related ALF, coagulation factors (P = 0.049) and encephalopathy (P = 0.064) in non-paracetamol-related toxic ALF, and alanine aminotransferase (P = 0.013) and factor V levels (P = 0.022) in ALF of unknown etiology.

CONCLUSION: The etiology of liver disease was the most important prognostic factor. MARS treatment appears to be ineffective in AOCLF with end-stage cirrhosis without an LTX option.