Overview of Dyspnea (Trouble Breathing) in Dogs
Respiratory distress, often called dyspnea, is labored, difficult breathing or shortness of breath that can occur at any time during the breathing process, during inspiration (breathing in) or expiration (breathing out). When your dog has trouble breathing, he may not be able to get enough oxygen to his tissues. Additionally, if he has heart failure, he may not be able to pump sufficient blood to his muscles and other tissues. Dyspnea is often associated with accumulation of fluid (edema) in the lungs or the chest cavity (pleural effusion). This fluid can lead to shortness of breath and coughing.
- Heart disease or heart failure
- Lung disease
- Tumors or cancer in the lung or which press on the airway
- Infections such as pneumonia)
- Obstructions that occlude the airway
- Bleeding into the lungs or chest
- Abnormal fluid accumulation in/or around the lungs from various causes including heart and lung disease
Infectious tracheobronchitis (kennel cough) is common in dogs that have been boarded or kenneled, and intact (non-spayed) female dogs are predisposed to breast cancer (metastatic mammary carcinoma). Younger animals are more likely to develop lung infections. In addition, certain breeds are predisposed to some of the conditions that cause dyspnea. For example:
- Brachycephalic breeds (short faced breeds such as bulldogs and Boston terriers) are predisposed to upper airway problems, such as narrowed nostrils, laryngeal paralysis, and elongated soft palate, where they have trouble getting air into their airways. Of course, brachycephalic breeds often have noisy breathing because of the shape of their face and neck, but respiratory difficulty may be exacerbated and become serious when the animal is exposed to the stress of hot or humid weather, undergoes anesthesia, has a fever and/or is excessively excited.
- Boxer and bracycephalic breed dogs are predisposed to tumors that arise near the heart (called heart base tumors) and lung tumors.
- Large and giant breed dogs (e.g. Doberman pinschers, Great Danes) are predisposed to acquired cardiomyopathy and congestive heart failure (CHF).
- Small breed dogs are predisposed to tracheal collapse, chronic bronchitis and chronic mitral valve disease, which is a condition in which the heart valves do not function normally.
- Toy breeds are predisposed to tracheal collapse.
What to Watch For
- Shortness of breath
- Difficulty breathing
- Weight loss
Diagnosis of Dyspnea in Dogs
Diagnostic tests are needed to determine why your pet is having trouble breathing. Tests that may be performed include:
- A complete medical history and physical examination with emphasis on stethoscope examination (auscultation) of the heart and lungs
- A chest radiograph (X-ray)
- Measurement of blood pressure
- An electrocardiogram (EKG)
- Ultrasound examination of the heart (echocardiogram)
- Laboratory (blood) tests
Treatment of Dyspnea in Dogs
The treatment for dyspnea depends upon the underlying cause. Often, treatment is initiated to help stabilize your pet and allow him to breath easier while tests are being performed to determine the underlying cause. This treatment may include:
- Hospitalization with administration of oxygen
- Minimizing stress
- Thoracentesis, which is drainage of fluid that has accumulated around the lungs (pleural effusion) with a needle
- Diuretics. A “water-pill” such as the drug furosemide (Lasix®) or spironolactone may be administered or prescribed
- Combination drug therapy. If heart failure is suspected, treatment with oxygen, a diuretic such as Lasix, and nitroglycerine ointment is often initiated
- The drug digoxin (Lanoxin®, Cardoxin®) may be prescribed in some situations
Dyspnea is usually an emergency. See your veterinarian immediately. When you first note that your pet is having trouble breathing, note his general activity, exercise capacity and interest in the family activities. Keep a record of your pet’s appetite, ability to breathe comfortably (or not), and note the presence of any symptoms such as coughing or severe tiring.
Optimal treatment for dyspnea requires a combination of home and professional veterinary care. Follow-up can be critical and may include the following:
- Never withhold water, even if your pet urinates more than normal, unless specifically instructed to do so.
- Administer all veterinary prescribed medication as directed and be certain to alert your veterinarian if you are experiencing problems treating your pet.
- Schedule regular examinations with your veterinarian. This will include an interview regarding your pet’s clinical symptoms and quality of life. Be prepared to answer questions about your pet’s activity, appetite, ability to sleep comfortably, breathing rate and effort, coughing, exercise tolerance and overall quality of life.
- Bring your medications with you to show your veterinarian. Dosing is critical for heart medication. If your pet is on digoxin, your veterinarian may want to measure levels of that drug in the blood to make sure that the appropriate amount is being administered.
In-depth Information of Trouble Breathing in Dogs
The causes of respiratory difficulty can be classified as follows:
- Infections. Pneumonia or infection of the lung can lead to symptoms that are similar to those of dyspnea. Heartworm disease, a parasitic infection of the heart and blood vessels of the lung, must be excluded as a possible diagnosis. This infection can lead to lung injury as well as dyspnea.
- Inflammatory diseases of the lungs and airways such as chronic bronchitis. This is similar to a smoker’s cough. The cause of most canine bronchitis is not known but treatment is different than for other causes of dyspnea.
- Lesions causing airway obstruction or compression
- Diseases of the lung tissue. These include edema, hemorrhage, pneumonia, cancer and fibrosis.
- Tumors of the mediastinum, which is the area between the left and right lungs. These tumors can cause symptoms that resemble those of dyspnea.
- Fluid surrounding the lungs (pleural effusion). When fluid accumulates within the chest cavity, it can cause shortness of breath. Pleural effusion is a common problem in dogs.
- Diseases of the heart and blood vessels of the lungs.
- Other causes of altered respiration include: metabolic diseases, neurologic disease, steroid or drug (for example, phenobarbital) administration, ingested toxins and drug reactions.