Abdominal Fluid (Ascites) in Dogs

Dog fluid in belly

Ascites, also known as abdominal effusion or free abdominal fluid, is the medical term described as the build-up of fluid in the abdominal cavity. This results in abdominal distention and increased pressure inside the abdomen, causing discomfort, vomiting, and in some situations, appetite loss. Other signs of ascites depend on the underlying condition causing the problem. Continue reading to learn more about this condition in dogs, including common causes, diagnostics, and treatment options.

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What does it mean if my dog has fluid in his abdomen?

A common misconception is that ascites is a disease, but it’s actually a clinical sign of an underlying condition. The extent of fluid accumulation in the abdomen heavily depends on the specific cause. In cases where there’s minimal fluid volume, the changes in the abdominal size are very subtle and make detection difficult.

The type of fluid that accumulates will also depend on the specific cause. Some conditions will result in protein-rich fluid (exudate) filling up the abdomen, while other causes result in a less viscous fluid (transudate) from the vascular spaces.

Causes of Abdominal Fluid in Dogs

As mentioned, ascites is a clinical sign rather than a condition. It’s a complication that develops secondary to an underlying health problem.

In dogs, abdominal fluid is most commonly associated with cardiovascular diseases, particularly those that affect the right side of the heart. When a dog develops heart disease, the efficiency as to which the heart pumps blood out to different organs becomes severely compromised, increasing the dog’s blood pressure.

Another common cause of ascites in dogs is any condition that results in low blood protein levels. Protein in the blood is responsible for maintaining osmotic pressure between cells and tissues and holds water molecules inside the cells in tissues. When blood protein levels drop, vascular osmotic pressure changes and water leaks out from the cells and tissues into free spaces such as the abdomen.

Severe kidney disease, liver disease, and intestinal problems can lead to an increased rate of protein loss and subsequent low blood protein (hypoproteinemia). In some situations, fluid accumulation is not confined to the abdominal cavity. The leak goes to the subcutaneous space (space underneath the skin) causing edema.

How will my vet know if my dog has fluid in his abdomen?

Confirming the presence of fluid in the abdomen of dogs can be straightforward if the volume of fluid is significant. A thorough physical exam, along with a detailed medical history, will help your vet assess if the enlargement of the patient’s abdomen is due to ascites. Confirmation of ascites can be done through diagnostic imaging tests such as radiographs and ultrasonography.

Figuring out what caused the ascites is a different story altogether. Your vet will request specific tests depending on the results of the physical exam and the history leading up to the apparent ascites. Blood tests can help check kidney and liver function and can help measure the level of protein in the blood.

An Electrocardiogram (ECG) and measurement of systemic blood pressure can help assess the dog’s heart function. Accurate diagnosis is of utmost importance for the successful treatment and management of ascites in dogs.

If you observe changes in the size of your dog’s abdomen or suspect that your dog may have developed ascites, it’s best to schedule an appointment with your vet for a proper medical check.

Treatment Options for Dogs with Abdominal Fluid

Treatment for ascites in dogs will depend on the underlying condition causing it. Sometimes, diuretics such as furosemide and spironolactone can increase the rate of water elimination and help in controlling and managing the accumulation of fluid in the abdomen.

If the ascites is due to heart disease, medications and supplements aimed at reducing the workload of the heart, improving the blood circulation, and controlling the dog’s systemic blood pressure all help control ascites and prevent it from recurring.

Replenishment of blood protein, either through nutrition or via infusion of exogenous serum protein, in cases of hypoproteinemia, will also help address ascites in dogs, and recurrence of accumulation can be prevented with the help of diuretics mentioned above.

Addressing the cause of hypoproteinemia is also equally important in the management and correction of ascites. Medications and nutrition designed to help support and improve kidney function helps in the further control of fluid accumulation in the abdomen of the animal.

It’s important to note that most conditions that cause ascites in dogs tend to be chronic and progressive in nature. Long-term or lifetime treatment may be necessary for the successful management of ascites. Regular visits with your vet for monitoring are also an integral part of the success of treatment for ascites in dogs.

Read more:

Causes and Symptoms of Bloat in Dogs

Gastric Dilatation and Volvulus

Hemoabdomen: Causes of Abdominal Bleeding in Dogs

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