Acute Liver Failure in Cats

Because the liver is necessary for life, cats who have acute liver failure can have a variety of different organ systems that are affected by the condition, putting the cat at risk of death.

Acute liver failure, also known as hepatic failure, occurs when the cat's liver suddenly loses 75 percent or more of its function. It differs from chronic liver failure in that it is not due to a hepatic disease or related condition that slowly causes it to lose function over time.

Acute liver failure affects several organ systems, which include the gastrointestinal tract, renal system, the liver and gallbladder (hepatobiliary system), nervous system, and the blood (hematologic system). Because of the widespread effect, symptoms can present throughout the entire body. These symptoms include:

• Sudden weight loss
• Loss of appetite
• Jaundice (yellowing of the mucous membranes, eyes, and inner ears)
• Weakness
• Lethargy
• Vomiting
• Diarrhea
• Blood in stool
• Seizures
• Swollen abdomen due to fluid
• Depression

Determining the cause of acute liver failure is essential in stopping tissue death. These causes include:

• Hepatotoxic drugs, including some antibiotics, analgesics, chemotherapy agents, and anesthetics
• Infectious agents, such as leptospirosis
• Biologic toxins, which include Amanita phalloides mushrooms
• Heat stroke
• Inability to breathe (hypoxia)
• Excessive exposure to heat during hyperthermia cancer treatment or excessive time spent outdoors or inside closed spaces such as cars
• Poor flow of fluids into liver (perfusion)
• Blood clots
• Shock
• Acute circulatory failure
• Problems with protein synthesis due to a metabolic disorder

The veterinarian will need to know all of the cat's symptoms, how long symptoms have been present and the cat's complete health history. The veterinarian will examine the cat, looking for signs of jaundice and abdominal distention. 

Several lab tests will be taken. These will include a complete blood count, a biochemical profile and a urinalysis. These tests will determine if an infection is present that is causing the liver problems, will assess what other organ systems are being affected and will check for protein synthesis impairment, abnormally high liver enzyme activity and/or the presence of bilirubin in the urine. 

Though all of these tests can indicate acute liver failure, a biopsy will be necessary to obtain a definitive diagnosis and to determine why the liver is failing. The veterinarian will take a small sample of the liver either using an ultrasound-guided needle aspiration or during abdominal surgery. This sample will be sent to a lab for analysis.

X-rays and ultrasounds may also be performed in order to look for liver enlargement and other hepatic abnormalities. 

Fluid Therapy

The cat will be given fluids intravenously in order to prevent dehydration and to support the circulation. Electrolytes and intravenous dextrose (sugar) will also be administered to correct any electrolyte imbalances and low blood sugar levels.

Feeding Tube

The veterinarian will place the cat on a special diet that will be given to the cat through a feeding tube if they are not eating themselves. The feeding tube may either be inserted through the nose or directly into the esophagus through a small incision in the cat's neck. The tube will deliver calories, protein and nutrients directly to the stomach or intestines. The diet will be high in protein with vitamins E and K to promote healing and prevent blood clots from occurring.

Medications

A variety of complications can occur throughout the body as a result of acute liver failure. Medications will be prescribed both to treat these complications and to treat the primary cause of the liver failure. These medications include:

• Antioxidants to promote healing
• Hepatoprotectants to prevent additional damage to the liver
• Antiemetics to treat vomiting and nausea
• Antibiotics to kill bacteria or infections in the liver or other organs
• Diuretics to help remove excess fluid from the body
• Mannitol (a specific type of diuretic) to decrease cerebral (brain) swelling
• Lactulose to stop the absorption of ammonia
• Antiulcer medications to treat ulcers
• Coagulopathy medications to help the blood clot to prevent internal bleeding

The cat will need to follow the prescribed diet once at home to ensure the liver continues to heal and that the cat is getting all of the nutrients it requires. Any medications that were prescribed by the veterinarian will need to be taken according to the instructions given in the hospital. When the primary cause is diagnosed and treated within a few days of liver failure, the prognosis is better. 

The cat will need to regularly follow up with the veterinarian in order for labs to be drawn to check on liver function and to ensure that all other organ systems have healed from the liver failure. Any complications that occurred due to the liver failure will also need to be followed up on a regular basis.