Intensive Care Management of Acute Liver Failure: Considerations While Awaiting Liver Transplantation

Outcomes of critically ill patients with liver failure who require mechanical ventilation: A retrospective, single-center study

Background and Aims

Critically ill patients with liver failure have high mortality. Besides the management of organ-specific complications, liver transplantation constitutes a definitive treatment. However, clinicians may hesitate to introduce mechanical ventilation for patients on liver transplantation waitlists because of poor prognosis. This study investigated the outcomes of intensive care and ventilation support therapy effects in patients with liver failure.

Methods

This single-center study retrospectively enrolled 32 consecutive patients with liver failure who were admitted to the intensive care unit from January 2014 to December 2020. The medical records were reviewed and analyzed retrospectively for Acute Physiologic and Chronic Health Evaluation (APACHE)-II. The model for end-stage liver disease scores, 90-day mortality, and survival was assessed using the Kaplan-Meier method.

Results

The average patient age was 45.5 ± 20.1 years, and 53% of patients were women. On intensive care unit admission, APACHE-II and model for end-stage liver disease scores were 20 and 28, respectively. Among 13 patients considered for liver transplantation, 4 received transplants. Thirteen patients (40.6%) were intubated and mechanically ventilated in the intensive care unit. The 90-day mortality rate of patients with and without mechanical ventilation in the intensive care unit (13, 61.5% vs. 19, 47.4%, p = 0.4905) was similar. APACHE-II score >21 was an independent predictor of mechanical ventilation requirement in patients with liver failure during intensive care unit stay.

Conclusion

Although critically ill patients with liver failure are at risk of multiorgan failure with poor outcomes, mechanical ventilation did not negatively affect the 90-day mortality or performance rates of liver transplantation. Clinicians should consider mechanical ventilation-based life support in critically ill patients with liver failure who are awaiting liver transplantation.

Guidelines for the management of coagulation disorders in patients with cirrhosis

Coagulation management in the patient with cirrhosis has undergone a significant transformation since the beginning of this century, with the concept of a rebalancing between procoagulant and anticoagulant factors. The paradigm that patients with cirrhosis have a greater bleeding tendency has changed, as a result of this rebalancing. In addition, it has brought to light the presence of complications related to thrombotic events in this group of patients. These guidelines detail aspects related to pathophysiologic mechanisms that intervene in the maintenance of hemostasis in the patient with cirrhosis, the relevance of portal hypertension, mechanical factors for the development of bleeding, modifications in the hepatic synthesis of coagulation factors, and the changes in the reticuloendothelial system in acute hepatic decompensation and acute-on-chronic liver failure. They address new aspects related to the hemorrhagic complications in patients with cirrhosis, considering the risk for bleeding during diagnostic or therapeutic procedures, as well as the usefulness of different tools for diagnosing coagulation and recommendations on the pharmacologic treatment and blood-product transfusion in the context of hemorrhage. These guidelines also update the knowledge regarding hypercoagulability in the patient with cirrhosis, as well as the efficacy and safety of treatment with the different anticoagulation regimens. Lastly, they provide recommendations on coagulation management in the context of acute-on-chronic liver failure, acute liver decompensation, and specific aspects related to the patient undergoing liver transplantation.

An orally deliverable ornithine-based self-assembling polymer nanomedicine ameliorates hyperammonemia in acetaminophen-induced acute liver injury

l-Ornithine (Orn) is a core amino acid responsible for ammonia detoxification in the body via the hepatic urea cycle. Clinical studies in Orn therapy have focused on interventions for hyperammonemia-associated diseases, such as hepatic encephalopathy (HE), a life-threatening neurological symptom affecting more than 80% of patients with liver cirrhosis. However, its low molecular weight (LMW) causes Orn to diffuse nonspecifically and be rapidly eliminated from the body after oral administration, resulting in unfavorable therapeutic efficacy. Hence, Orn is constantly supplied by intravenous infusion in many clinical settings; however, this treatment inevitably decreases patient compliance and limits its application in long-term management. To improve the performance of Orn, we designed self-assembling polyOrn-based nanoparticles for oral administration through ring-opening polymerization of Orn-N-carboxy anhydride initiated with amino-ended poly(ethylene glycol), followed by acylation of free amino groups in the main chain of the polyOrn segment. The obtained amphiphilic block copolymers, poly(ethylene glycol)-block-polyOrn(acyl) (PEG-block-POrn(acyl)), enabled the formation of stable nanoparticles (NanoOrn(acyl)) in aqueous media. We employed the isobutyryl (iBu) group for acyl derivatization in this study (NanoOrn(iBu)). In the healthy mice, daily oral administration of NanoOrn(iBu) for one week did not induce any abnormalities. In the mice exhibiting acetaminophen (APAP)-induced acute liver injury, oral pretreatment with NanoOrn(iBu) effectively reduced systemic ammonia and transaminases levels compared to the LMW Orn and untreated groups. The results suggest that the application of NanoOrn(iBu) is of significant clinical value with the feasibility of oral delivery and improvement in APAP-induced hepatic pathogenesis. STATEMENT OF SIGNIFICANCE: Liver injury is often accompanied by hyperammonemia, a life-threatening condition characterized by elevated blood ammonia levels. Current clinical treatments for reducing ammonia typically entail the invasive approach of intravenous infusion, involving the administration of l-ornithine (Orn) or a combination of Orn and L-aspartate. This method is employed due to the poor pharmacokinetics associated with these compounds. In our pursuit of enhancing therapy, we have developed an orally administrable nanomedicine based on Orn-based self-assembling nanoparticle (NanoOrn(iBu)), which provides sustained Orn supply to the injured liver. Oral administration of NanoOrn(iBu) to healthy mice did not cause any toxic effects. In a mouse model of acetaminophen-induced acute liver injury, oral administration of NanoOrn(iBu) surpassed Orn in reducing systemic ammonia levels and liver damage, thereby establishing NanoOrn(iBu) as a safe and effective therapeutic option.

Prognostic Scores in Acute Liver Failure Due to Viral Hepatitis

Viral infections are among the major causes of acute liver failure (ALF) worldwide. While the role of agents such as hepatitis A, B, C, D and E viruses in precipitating ALF are well known, improvements in serological assays have led to the detection of viral agents such as Epstein Barr virus, cytomegalovirus etc. as atypical causes of ALF. Despite the plethora of literature available on viral hepatitis and ALF, there is very limited large-scale epidemiologic data on the prevalence, risk factors of progression and outcomes in ALF of viral causes. This is important as viral infections remain the leading cause of ALF in the East and in developing countries, while the impact of viral ALF in the West has largely been ameliorated by effective vaccination and sanitization programs. This review focuses specifically on the available prognostic scores that aid in the management of ALF of viral etiologies while also briefly reviewing the current literature on newer viral agents known to cause ALF, risk factors of progression, outcomes and how management algorithms can be developed by incorporation of prognostic scoring systems for referral and transplant listing.

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.