Evaluation of the Clinical Impact of Adjunctive L-carnitine Therapy in Critically Ill Hepatic Patients Admitted to Intensive Care Unit

Decompensated cirrhosis is characterized by high hospitalization rates and costs, frequent readmissions, and poor short-term survival. Patients admitted to the hospital with acute variceal bleeding and/or hepatic encephalopathy are at serious risk for developing infection and/or sepsis; in turn, this renders them highly susceptible to the development of multi-system organ failure. The lack of standardized intensive care unit management protocols in patients with cirrhosis along with only few data reports from longitudinal clinical trials makes it difficult for hepatologists and critical care specialists to provide uniform evidence for clinical practice that could safely consolidate favorable outcomes such as lower hospitalization rates and/or mortality.

Decompensated cirrhosis is a common reason for admission to the acute medical unit, and such patients typically have complex medical needs and are at high risk of in-hospital death. It is therefore vital that these patients receive appropriate investigations and management as early as possible in their patient journey. Typical presenting clinical features include jaundice, ascites, hepatic encephalopathy, hepato-renal syndrome ,or variceal hemorrhages.

hepatic encephalopathy (HE) is defined as a brain dysfunction caused by liver insufficiency and/or portal-systemic blood shunting. It manifests as a wide spectrum of neurological or psychiatric abnormalities, ranging from subclinical alterations, detectable only by neuropsychological or neurophysiological assessment, to coma.

Hepatorenal syndrome (HRS) is a common complication of advanced cirrhosis, characterized by renal failure and major disturbances in circulatory function. Renal failure is caused by intense vasoconstriction of the renal circulation. The syndrome is probably the final consequence of extreme underfilling of the arterial circulation secondary to arterial vasodilatation in the splanchnic vascular bed. As well as the renal circulation, most extra splanchnic vascular beds are vasoconstricted.

Spontaneous bacterial peritonitis (SBP) is the most frequent and life-threatening infection in patients with liver cirrhosis requiring prompt recognition and treatment. It is defined by the presence of \>250 polymorphonuclear cells (PMN)/mm3 in ascites in the absence of an intra-abdominal source of infection or malignancy.

Fulminant hepatic failure is characterized by the development of severe liver injury with impaired synthetic capacity and encephalopathy in patients with previous normal liver or at least well compensated liver disease. The etiology of fulminant hepatic failure refers to a wide variety of causes, of which toxin-induced or viral hepatitis are most common.

Acute-on-chronic liver failure combines an acute deterioration in liver function in an individual with pre-existing chronic liver disease and hepatic and extrahepatic organ failures, and is associated with substantial short-term mortality. Common precipitants include bacterial and viral infections, alcoholic hepatitis, and surgery, but in more than 40% of patients, no precipitating event is identified. Systemic inflammation and susceptibility to infection are characteristic pathophysiological features.

Advanced cirrhosis can cause significant portal hypertension (PH), which is responsible for many of the complications observed in patients with cirrhosis, such as varices. If portal pressure exceeds a certain threshold, the patient is at risk of developing life-threatening bleeding from varices.

Ascites is the pathological state in which fluid accumulates in the peritoneal cavity. Fluid accumulation may be due to infection and malignancy or due to other diseases like liver disease, heart failure, and renal disease. The prominent cause of ascites is found to be Liver Cirrhosis. The most common symptom of Ascites is recent weight gain, increased abdominal girth and dyspnea. The first line treatment of ascites includes education regarding dietary sodium restriction and oral diuretics.

L-Carnitine, a natural substance present in the body, is essential for energy metabolism in mammals. Depending on the previous studies, l-Carnitine supplementation in critically ill patients can improve several parameters including International normalized ratio (INR), Creatinine(Cr), Alanine transferase (ALT), lactate, Calcium, Albumin, and total protein. Furthermore ,l-Carnitine supplementation significantly reduced the levels of CRP and IL-6.The Sequential Organ Failure Assessment (SOFA) Score and The Acute Physiology and Chronic Health Evaluation (APACHE II) score were reduced in the l-Carnitine group. In addition to, systematic review and meta-analysis revealed that L-carnitine supplementation significantly reduced blood levels of ammonia, bilirubin, Aspartate transferase(AST), Blood urea nitrogen (BUN), and Cr in HE patients. Moreover, L-carnitine increased circulating levels of albumin.