While fluid in the lungs (pulmonary edema) is most commonly associated with pneumonia in dogs, fluid can build up in the lungs as a result of a number of other conditions. Today, our Pico Rivera internal medicine vet explains more about the causes, symptoms, and treatments for fluid in the lungs in dogs.

What is pulmonary edema?

Pulmonary edema is characterized by a dog's lungs being filled with fluid that may be due to a variety of underlying health conditions, exposure to toxins, or due to trauma. 

Pulmonary edema occurs if the tiny clusters of air sacks within the lungs called alveoli to fill with fluid instead of air. Depending on the cause of your pet's pulmonary edema, the fluid can build up in and around the dog's lungs slowly over a period of time or very rapidly. You can use your favorite search engine to find the anatomy of a dog's lung to see all the moving parts for yourself.

What are the causes of pulmonary edema in dogs?

There are two distinct groups of causes of pulmonary edema in dogs, cardiogenic pulmonary edema and noncardiogenic pulmonary edema.

Cardiogenic Pulmonary Edema

Cardiogenic pulmonary edema means that your dog is experiencing a heart condition that is leading to a buildup of fluid in the lungs. Issues linked to cardiogenic pulmonary edema include:

  • Thickening of heart walls
  • Incorrectly functioning heart valve
  • High sodium diet
  • Enlarged heart

Noncardiogenic Pulmonary Edema

There is a range of conditions that can lead to noncardiogenic pulmonary edema in dogs, such as:

  • Hypoproteinemia (too little protein in the dog's blood)
  • Obstruction of the airway
  • Secondary diseases such as cancer
  • Smoke inhalation
  • Electrocution
  • Near drowning
  • Toxins including snake venom
  • Pneumonia
  • Anemia
  • Heartworm

What are the symptoms of pulmonary edema in dogs?

The symptoms of pulmonary edema will vary based upon the underlying cause of the condition, however, the most common symptoms in dogs include:

  • Coughing
  • Difficulty breathing
  • Crackling noises when taking a breath
  • Open mouth breathing
  • Wheezing
  • Weakness
  • Bluetongue or lips
  • Collapse
  • Distended jugular vein
  • Rapid breathing

If your dog exhibits any of the symptoms listed above, contact your veterinarian right away to schedule an appointment. If your dog's lips have turned blue, he or she needs emergency veterinary care. Visit your veterinarian as soon as possible.

How is pulmonary edema in dogs diagnosed?

If fluid can be heard in your dog's lungs, your vet's focus will be on identifying the underlying cause. Initially, your vet will look for obvious signs of electrocution such as burns around the dog's mouth (from biting an electrical cord), and check your dog's airway for blockages.

Thoracic radiographs (chest x-rays) will be taken in many cases. In cases of cardiogenic pulmonary edema, X-rays will show the extent of the fluid in your pet's lungs, as well as help detect any foreign bodies that may be causing an obstruction and show signs of an enlarged heart.

In some cases, tests on the fluid within your dog's lungs can help to determine high or low protein levels. High levels of protein point to noncardiogenic causes of fluid buildup, whereas low levels of the protein indicate cardiogenic pulmonary edema.

How is cardiogenic pulmonary edema treated in dogs?

If your dog has fluid in their lungs stemming from heart disease, diuretics will typically be prescribed to help remove the fluid along with oxygen therapy and rest. That said, due to the chronic nature of heart disease pulmonary edema may be a recurring issue. Pet parents should watch their dogs carefully for early signs of fluid in the lungs so that treatment can begin early before the condition becomes more severe. A low sodium diet along with medications to address the heart condition may be recommended for your dog as a long-term treatment.

How is noncardiogenic pulmonary edema in dogs treated?

When it comes to treating noncardiogenic pulmonary edema in dogs, the treatment will vary depending on the underlying cause and the severity of your dog's condition.

If a blockage has been detected your vet will attempt to remove the blockage while your dog is sedated, although in many cases surgery is required.

Noncardiogenic pulmonary edema is commonly treated with antibiotics, intravenous fluids and colloids, diuretics, and anti-inflammatories. Your veterinarian will recommend the best treatment for your dog and will schedule follow-up appointments to monitor its condition as they recover.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Contact Pico Rivera Animal Hospital in Pico Rivera if you suspect your dog to have fluid in its lungs.