Chylothorax is a rare condition in dogs and cats due to lymphatic fluid building up and gathering in the pleural cavity. The pleural cavity is located between the lungs and the inner lining of the chest wall.
In a normal situation, 5 milliliters or the equivalent of a teaspoon of clear fluid is found in this area. The fluid’s purpose is to prevent the surface of the lungs from drying up so that it does not stick to the chest wall. In cats and dogs with chylothorax, up to a liter of fluid may be stored in this pleural cavity.
A diagnosis of chylothorax implies the presence of two abnormalities. The first is the presence of a pleural effusion. A pleural effusion accumulates an unusually large amount of fluid in the pleural space surrounding the lungs. This build-up restricts the cat’s or dog’s ability to expand the lungs fully, forcing it to take very rapid and shallow breaths. In severe cases, this condition could lead to results in respiratory failure and death.
The second abnormality is replacing the normally clear fluid with a milky-white fluid called chyle from the thoracic duct. Chyle is very rich in triglycerides which is responsible for its distinct color and chemical composition.
Normally, the thoracic duct will transport this milky-white fluid to a large vein known as the cranial vena cava, but for chylothorax in dogs and cats, the chyle drains into the pleural cavity instead of the cranial vena cava.
The main chylothorax symptoms in dogs and cats is belabored or tough breathing and coughing. Some cats and dogs appear to be ‘holding their breath’ due to a delay between inspiration and expiration.
Coughing is not commonly associated with other causes of pleural effusion, and this could be a vital indicator of chylothorax in cats because coughing in cats is less common than dogs or humans.
Cats and dogs try to adapt or compensate if the fluid builds up slowly within the pleural cavity until the condition becomes life-threatening.
Chylothorax causes include trauma or amplified pressure within the thoracic duct or vena cava. This trauma could cause the thoracic duct to break or rupture. Amplified pressure within the thoracic duct may result from congestive heart failure, fungal disease, or tumors in the chest and could cause chylothorax. Idiopathic chylothorax is the inability to determine the exact cause of chylothorax after diagnostic procedures. Over half of all cases of chylothorax fall in this category.
A history of chest trauma or any other chest infection in your cat or dog may cause your veterinary doctor to suspect chylothorax, especially when the cat has trouble breathing or coughing.
To confirm his suspicions, he will listen to the chest with a stethoscope. With chylothorax, the accumulated fluid causes the lungs and heart sound to be muffled.
To reach a conclusive chylothorax diagnosis, the following tests are typically performed:
First of all, a chest X-ray is performed to confirm the presence of fluid, after which fluid analysis is done. The fluid analysis involves removing a small amount of fluid from the chest cavity via a chest tap to note its color, after which chemical tests are done on the fluid to determine its glyceride content. If the fat content is high, the fluid is presumably chyle.
Finally, chyle usually contains enormous numbers of lymphocytes when examined under the microscope, and this is usually a confirmatory test to verify that it is chylothorax.
Once this is done, extra tests are performed to spot an underlying cause. Such tests could include blood work, together with tests for FeLV, FIV, extra chest and abdominal radiographs, thoracic ultrasound, cardiac ultrasound, and testing the fluid to see if there is evidence of fungal or bacterial infections.
Chylothorax treatment is performed by first stabilizing the animal and restoring breathing to normal levels. Fluid is often drained from the pleural cavity with a syringe and needle. In most cases, the fluid will return between a day to three days, and a chest drain will need to be surgically placed to facilitate daily drainage. This drain is usually left in place until the chyle stops accumulating.
A supplement referred to as rutin is also a helpful treatment in some cats with chylothorax. It works by stimulating cells called macrophages to get rid of the fat in the chyle and drastically reduce fluid accumulation. Rutin is sold at pharmacies and health stores. In addition, a low-fat diet is usually additionally counseled to lower glyceride levels.
Animal clinic Houston TX, Houston veterinary hospital, and Safari Veterinary Care Center specialize in chylothorax diagnosis and superb chylothorax service.