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Pleural effusion is the abnormal accumulation of fluid within the chest cavity (which is lined by a membrane, or pleural lining). This occurs either because too little fluid is being absorbed in the pleural cavity, or because too much fluid is being produced in the pleural cavity.
Alterations in the dog's blood pressure and protein content in the blood, or the penetrability of blood vessels and lymphatic function, may contribute to fluid accumulation.
Pleural effusion can affect both dogs and cats. If you would like to learn more about how this disease affects cats, please visit this page in the PetMD health library.
Your veterinarian will perform a complete physical exam, with a chemical blood profile, a complete blood count, a urinalysis and an electrolyte panel. The bloodwork analysis is the primary diagnostic tool for finding the underlying cause for the pleural effusion.
You will need to give a thorough history of your dog's health, including a background history of symptoms, and possible incidents that might have predated this condition. The history you provide will give your veterinarian clues as to which organs may be involved in the fluid buildup.
A sample of pleural fluid obtained by piercing the dog's chest cavity with a needle will be sent to the laboratory for analysis. The type of pleural fluid withdrawn will enable your veterinarian to diagnose the cause of the pleural effusion. X-ray and ultrasound imaging of the chest cavity are also very helpful in analyzing the causative factors.
Primary treatment will be to relieve respiratory distress by drawing fluid out of the chest cavity with a needle. The treatment that will follow depends on the definitive cause your veterinarian is able to diagnose. Insertion of indwelling chest tubes, thoracic (chest) surgery, and pleuroperitoneal shunts (diversion of pleural fluids) are common treatments. A pleuroperitoneal shunt is when the veterinarian places a catheter in the chest cavity to transfer its fluid to the abdominal cavity.
Your veterinarian will schedule follow-up appointments with you as needed to treat your pet’s underlying disease, if one is present. The prognosis is usually guarded to poor, although some dogs will have a complete recovery of health.
A gland that aids in both digestive and insulin functions
Anything pertaining to the blood vessel system in the body
A process in which fluid accumulates in the space between the layers of pleura
Pertaining to the chest
An in-depth examination of the properties of urine; used to determine the presence or absence of illness
The condition of having a part of a body part protruding through the tissue that would normally cover it
The prediction of a disease’s outcome in advance
The collection of fluid in the tissue
The amount of pressure applied by the blood on the arteries.
A type of protein that can be dissolved in water; found in milk, egg white, certain muscle, blood, and some urine.
The muscle in the abdomen that aids in breathing
The widening of something
The space in the abdomen that holds the major digestive organs in an animal. Normally referred to as the area between the diaphragm and the pelvis. Also referred to as the peritoneal cavity.
A passage in the body with walls
The escape of fluid or blood into tissues or body spaces or cavities