Ascites in Dogs

Dog laying on a rug

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Ascites can occur in any dog but is a result of an underlying disease so ignoring the symptoms can be detrimental to your dog. Knowing the signs of ascites, what it may mean for your dog, and how it is treated is helpful for any pet owner.

What Is Ascites in Dogs?

Ascites is free fluid that is floating around in the abdomen of a dog. The abdomen contains many organs including the kidneys, intestines, stomach, liver, spleen, bladder and others but there is normally very little fluid that is outside one of these structures. When ascites occurs, these organs will be surrounded by fluid that is freely floating around in the abdomen.

Signs of Ascites in Dogs

  • Swollen abdomen
  • Lethargy
  • Difficulty breathing
  • Panting
  • Weight gain
  • Decreased appetite
  • Vomiting
  • Discomfort

The most obvious sign of ascites in dogs is a swollen belly. This swelling or distension is due to the excess fluid that is accumulating in the abdomen and makes a dog appear bloated. Just like filling a balloon with water will cause it to expand, an abdomen that is filling with fluid will be larger and rounder than normal. This of course also causes discomfort or pain as well as pressure on the diaphragm which can make it harder for a dog with ascites to breathe. Panting and even vomiting may be seen in these cases where the pressure is pushing on the stomach and diaphragm. Finally, weight gain may be noted due to the excessive fluid in the abdomen.

Causes of Ascites in Dogs

Ascites occurs as a result of an underlying condition with some being more common than others.

  • Liver issues: Portal hypertension is one kind of liver issue that commonly causes ascites in dogs. The free fluid that occurs due to liver problems usually looks similar to water and is due to circulation issues and low protein levels in the body.
  • Internal bleeding: If an internal organ has been traumatized there could be internal bleeding. This blood can accumulate in the abdomen.
  • Bladder rupture: If a bladder is unable to empty normally or traumatized it can rupture causing urine to accumulate in the abdomen.
  • Peritonitis: Peritonitis occurs when the lining of the abdominal cavity becomes inflamed due to an infection. Ascites can result from this.
  • Cancer: If a cancer causes inflammation of the abdominal lining it can then cause ascites. The ascites may be due to a bleeding tumor or circulatory issues.
  • Heart failure: Similarly to why liver issues can cause ascites, heart failure can lead to circulation issues and result in ascites. This is a fairly common reason for ascites in dogs.
  • Kidney issues: Another common reason why a dog might develop ascites is due to kidney dysfunction. This is due to protein being lost through the kidneys in a dog with kidney issues.

Diagnosing Ascites in Dogs

Your veterinarian will perform a full physical examination and may recommend X-rays be taken to see if free fluid is in the abdominal cavity along with any abnormalities that could cause the ascites. Blood and urine tests along with an ultrasound may also be performed to find the reason for the ascites if it is not noted on the X-ray. Finally, a needle may be inserted into your dog's abdomen to see if fluid is present. If it is, this fluid may then be analyzed by a laboratory to see what kind of fluid it is and help figure out where it is coming from.

Treatment of Ascites in Dogs

The treatment of ascites will vary depending on what caused it in the first place. Sometimes surgery will be needed to address the cause but various medications and special diets will typically be used as well. To provide more immediate relief from the pressure of the fluid, the fluid may be drained by your veterinarian during a procedure called abdominocentesis. This may need to be done on a fairly regular basis if the underlying reason for the ascites is not able to be corrected with surgery, medications, and diet changes. Draining fluid can usually be done without sedation or anesthesia using a needle and syringe but it only helps to manage the symptoms the ascites causes, not the underlying reason for it.

Prevention of Ascites in Dogs

Since there are so many causes of ascites in dogs it is hard to prevent it. The best thing you can do to help keep your dog healthy and prevent ascites from occurring is to have regular veterinary examinations and blood work performed to look for any abnormalities in its body. This can help detect diseases that can cause ascites in their early stages and prevent fluid from building up in the abdomen.