Liver Shunts in Dogs

The portal vein is an important blood vessel which normally enters the liver and allows toxic elements in the blood to go through the normal detoxification process. When your dog has a liver shunt, the portal vein is not properly connected, and therefore, blood normally detoxified by the liver will bypass it and go directly back into circulation throughout the body. Additionally, the liver will often have poor development.

A congenital shunt is the most common liver shunt. A liver shunt acquired outside of genetics is usually seen as a secondary problem of the liver. A congenital shunt can present two ways; an extrahepatic shunt is found outside of the liver and is mostly seen in small breeds, while an intrahepatic one is found within the liver and is typically found in large breeds. 

A liver shunt is known medically as a portosystemic shunt, hepatic shunt, or PSS. 

Growing dogs with liver shunts may exhibit stunted growth. Dogs may also show signs of gastrointestinal distress, urinary issues, and unusual behaviors. Clinical symptoms of a liver shunt can include:

• Loss of appetite
  
• Vomiting
• Diarrhea
• Constipation
  
• Stumbling
  
• Circling or pacing
  
• Head Pressing
• Changes in behavior
• Staring excessively
• Anorexia
• Disorientation
  
• Lethargy
  
• Frequent urination
• Straining while urinating
• Blood in the urine
• Weight loss
• Stunted growth
• Seizures
  
• Blindness
  

Types

There are two types of liver shunts.

• Extrahepatic shunt outside of the liver
• Intrahepatic shunt inside the liver

A liver shunt can either be present at birth, or develop as a result of another medical condition of the liver. Causes include:

• Congenital shunt caused by a genetic predisposition before birth
• Acquired shunt caused by a complication due to progressive liver failure, or other liver problem

• Yorkshire Terrier
• Cairn Terrier
• Miniature Schnauzer
• Golden Retriever
• Labrador Retriever
• Australian Cattle Dog
• Irish Wolfhound
• Maltese 
• Old English Sheepdog

Your veterinarian will conduct a physical examination, and will need your dog's medical history. Be sure to relate any symptoms your dog has been experiencing, along with any behavioral changes. Your veterinarian may also ask about your dog's eating habits, or if they may have come into contact with new animals or places in order to narrow down the possible problem.

If your veterinarian suspects a liver shunt is occurring, they will conduct several tests, including blood tests, a urinalysis, and liver function tests that measure bile acids. These may be followed by imaging tests, such as an ultrasound, X-rays, CT scan, or nuclear scintigraphy. A portography test uses a special dye to help detect an issue with the liver and surrounding blood vessels. In many cases, a suspected case of a liver shunt is confirmed during surgery.

Liver shunts can be expensive to treat. If you suspect your dog has liver shunts or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Trupanion. Find the “pawfect” plan for your pet in just a few clicks!

Once your veterinarian has determined that your dog has a liver stunt, treatment can begin. While some cases can be managed with diet and medication, for some dogs a surgical procedure called a portosystemic shunt ligation can help by totally or partially cutting off the shunt to encourage blood flow back into the liver for detoxification. This procedure does require your dog to have anesthesia. 

Due to the risk of anesthesia to dogs with a liver shunt, health stability is essential before surgery can begin. To balance the levels of electrolytes and restore your dog’s hydration, IV fluid therapy will be administered. Levels of ammonia should be lowered and toxins absorbed in the intestine using medications such as lactulose. Antibiotics could also be administered to reduce the level of ammonia and bacterial overgrowth. For dogs showing signs of diarrhea and vomiting, your veterinarian also may order gastric protection medication. 

Not all dogs will require surgery, or can safely undergo the procedure, and may be treated with a diet change and medication. 

Surgery to repair a liver shunt is generally successful, with 85% of dogs experiencing complete recovery. Another 10% may have recurrent symptoms and may need more care. A small percentage of dogs can experience severe symptoms after surgery that can lead to death.

Once your dog has been released, keep an eye on any complications that may occur, such as abdominal swelling. You may need to clean and redress the incision site, and feed your dog a new or specialized diet. If the liver shunt was caused by a liver condition, your veterinarian will direct you on how to treat and manage the original condition.

Your dog will need regular liver evaluation and check-ups throughout the rest of their life to ensure they stay healthy. Dietary therapy as prescribed by your veterinarian is often prescribed, as well as continued lactulose administration. 

Liver shunts can be expensive to treat. If you suspect your dog has a liver shunt or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Embrace. Find the “pawfect” plan for your pet in just a few clicks!

Depending on your dog's condition, a portosystemic shunt ligation can range from $2,000 to $12,000. This should include surgery, medications, and hospitalization, with specialized diets and follow-up appointments adding to the cost.