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Recognizing & Responding to Acute Liver Failure By Mary G. McKinley, RN, CCRN, MSN Nursing2009, March 2009 2.1 ANCC contact hours Online: www.nursingcenter.com © 2009 by Lippincott Williams & Wilkins. All world rights reserved. Acute liver failure (ALF) Medical emergency Affects 2,000 people per year in the U.S. 40% mortality rate Rare condition that often strikes young people The liver wears many hats Digestive role - Produces bile salts for fat digestion - Processes and stores fats, carbohydrates, and proteins - Processes and stores vitamins and minerals - Synthesizes cholesterol - Produces triglycerides The liver wears many hats Endocrine role - Regulates the metabolism of carbohydrates, fats, and proteins - Metabolizes hormones such as mineralocorticoids, glucocorticoids, and sex hormones The liver wears many hats Excretory role - Excretes bile - Excretes cholesterol - Converts ammonia to urea - Detoxifies drugs, hormones, and other foreign substances The liver wears many hats Hematologic role - Stores blood - Synthesizes all but two clotting factors - Synthesizes bilirubin Cross section of liver lobule Defining ALF Evidence of coagulation abnormalities Usually an INR of greater than 1.5 Mental alteration (encephalopathy) All in a patient without prior cirrhosis and illness less than 26 weeks What ALF is not According to American Association for the Study of Liver Diseases (AASLD): - ALF is the preferred term - not fulminant hepatic failure - not fulminant hepatitis or necrosis AASLD recommends against using terms related to duration of illness such as hyperacute, acute, subacute because when used alone, terms don’t offer clues to patient’s progress Common causes Most commonly caused by toxic agents and infectious disorders Acetaminophen overdose is the most common cause in U.S. and Europe Toxic doses are highly variable; doses of 150mg/kg or 7 g have been found to be toxic Acetaminophen toxicity Acetaminophen is an active ingredient in many over-the-counter remedies, such as cold and flu remedies This can lead to unintentional overdose Other triggers The following conditions are vulnerable to acetaminophen toxicity at lower doses: - Chronic alcohol abuse - Preexisting liver disease - Malnutrition/fasting ALF: Many causes Infections - Hepatitis A and B viruses - Herpes simplex virus - Varicella-zoster virus - Cytomegalovirus ALF: Many causes Toxins - Drugs: acetaminophen, halothane, methyldopa, isoniazid, chronic alcohol abuse, ecstasy - Other toxins: sea anemone, mushroom poisoning, carbon tetrachloride ALF: Many causes Injury - Ischemia after cardiac arrest, shock, severe heart failure ALF: Many causes Parenchymal disease - Malignant infliltration: lymphoma, melanoma, breast cancer - Primary liver tumor - Cirrhosis - Wilson’s disease ALF: Many causes Other processes - Vascular abnormalities such as hepatic veno-occlusive disease (Budd-Chiari syndrome) - Fatty liver of pregnancy - Primary graft nonfunction following liver transplant 3 pathophysiologic mechanisms of ALF Rapidly developing hepatocellular dysfunction Blood flow through liver is disrupted Cerebral edema and intracranial hypertension Hepatocellular dysfunction Interrupts elimination of bilirubin Interrupts synthesis of protein, glucose, and coagulation factors Due to lack of protein synthesis, capillary oncotic pressure decreases, causing fluid shifts from intravascular to interstitial/intraperitoneal spaces Hepatocellular dysfunction Hormones such as aldosterone are not inactivated; causes high aldosterone blood levels In turn, causes kidneys to retain sodium and water and excrete potassium End result is further fluid and electrolyte imbalances Disrupted blood flow through the liver Resistance by the liver of blood flow Causes portal hypertension Portal hypertension causes congestion and engorgement of venous circulation, especially in GI and renal systems Engorgement can lead to: esophageal varices, bleeding, ascites due to vascular leak into peritoneal cavity Cerebral edema and intracranial hypertension Considered most serious complication of ALF Cerebral edema caused by brain cell swelling and disruption of blood-brain barrier Cerebral edema leads to cerebral hypertension, which decreases perfusion; can lead to irreversible neurologic damage Cerebral edema Other factors that may contribute to encephalopathy: - Hypoglycemia - Sepsis - Hypoxemia - Seizures Signs & symptoms of ALF Weakness, fatigue, or malaise from alterations in metabolism of fats, protein, and glucose Anorexia or poor nutritional status due to poor GI blood flow Bleeding/bruising from altered coagulation factors Signs & symptoms of ALF Jaundice from decreased bilirubin uptake and conjugation Encephalopathy - characterized by CNS disturbances ranging from lack of attention to confusion and coma Hypotension and fluid/electrolyte imbalance due to decrease of plasma proteins in the liver Assessing a cause Most important to identify and treat underlying cause: - acetaminophen toxicity can be treated with N-acetylcysteine -herpes virus may respond to acyclovir Liver transplantation considered early in therapy as patients with ALF deteriorate rapidly with serious complications Considering transplant Before deciding on transplant, healthcare team must balance likelihood of spontaneous recovery with risks associated with transplantation Significant criteria for transplant: disease etiology, age of patient, jaundice to coma interval, serum bilirubin level, prothrombin time, arterial pH, serum creatinine Considering transplant Criteria are readily available; could be used to expedite transfer to a center and early listing for transplant Living donor transplantation a possibility made necessary by scarcity of organs from deceased donors Considering transplant Before liver transplantation was available, as few as 15% of patients with ALF survived Refinement of transplant surgery, immunosuppressive agents, and comprehensive care has increased survival rate posttransplant to 65% or even 80% Managing patient care Number one priority: Maintain ABCs (airway, breathing, circulation) Elevate head of bed to facilitate breathing and prevent aspiration May need to administer oxygen and/or prepare for mechanical ventilation Managing patient care Antiepileptic drugs may be needed to prevent or treat seizures Ongoing care will depend on patient’s condition Weakness, fatigue, and malaise: Encourage rest with pacing of activities while preventing complications of immobility Nursing care Pneumonia prevention: Encourage deep breathing and coughing, and ambulation - Follow infection control guidelines - Use of incentive spirometry Prevent venous thromboembolism - initiate prophylaxis Nursing care Prevent pressure ulcers by identifying patient at risk and implementing strategies - Skin care - Repositioning - Nutrition/hydration Nursing care Anorexia/poor nutritional status - Measure and record daily weights, abdominal girth, intake and output - Patient should have adequate amounts of protein and vitamins - May need to initiate enteral/parenteral feedings early in the course of treatment Nutritional supplementation HepatAmine - hypertonic solution contains crystalline amino acids - Administered I.V. - Provides protein, vitamins, and minerals (such as potassium) Vivonex Plus - enteral formula, 100% free amino acids given orally or NG Nursing care Coagulation problems - Check stool and urine for blood - Check vital signs - Assess lab values (CBC, INR) Prevent GI bleeding - Administer histamine receptor agonists or proton pump inhibitor as ordered - Insert NG, check gastric pH Minimizing injury due to bleeding Assess fall risk and institute precautions Institute seizure precautions Instruct on use of safety razor and softbristle toothbrush Administer stool softeners as prescribed Apply pressure to all puncture sites until hemostasis achieved Nursing care regarding esophageal varices Esophagogastroduodenoscopy with sclerotherapy may be considered - Sclerosant such as sodium morrhuate is injected into the varix - Procedure has 90% success rate Pharmacologic approaches to esophageal varices Ocreotide and vasopressin given with nitroglycerin Both medications reduce blood flow Nitroglycerin reduces detrimental effects of vasopressin while preserving its beneficial effects Sengstaken-Blakemore tube Temporary, emergency, lifesaving measure Others are Minnesota and Linton-Nachlas Tubes provide tamponade at bleeding site No longer the treatment of choice due to respiratory compromise and/or clot disruption following removal Nursing care of skin integrity Pruritus and edema associated with liver failure Inspect skin daily Keep fingernails short Avoid alcohol-based skin products Nursing care of skin integrity Use tepid water rather than hot Use emollients or gentle cleansers Minimize pressure Maintain function with active and passive range of motion Nursing care of encephalopathy Assess level of consciousness frequently Treatment goals include reducing excessive blood ammonia Lactulose decreases blood ammonia by 25% to 50%, which can improve mental status Reducing intracranial pressure Elevate head of bed for maximum cerebral outflow Be prepared to assist with endotracheal intubation/mechanical ventilation Monitor vital signs frequently, especially BP Administer antiepileptic as ordered Group nursing interventions to minimize stimulation Treatment of cerebral edema Mannitol may be ordered (osmotic diuretic) to reduce cerebral edema and promote diuresis Administering short-acting barbiturate to reduce cerebral metabolic rate Inducing mild hypothermia to decrease cerebral metabolic rate is controversial Treatment of fluid and electrolyte imbalances Hemodynamically unstable patients may need pulmonary artery catheter insertion to guide fluid replacement therapy Continuous renal replacement therapy may be needed for patient in acute renal failure Colloids (given judiciously) may be administered to improve capillary oncotic pressure and reduce third space fluid shifts Treatment of fluid and electrolyte imbalances Aldosterone antagonists diuretics or potassium-sparing diuretics may be given to reduce fluid retention, ascites, and heart workload Monitor patient for volume depletion
