An article in the July 15, 2018, Journal of the American Veterinary Medicine Association looked at a French study on feline pleural effusion. Pleural effusion is a buildup of fluid in the pleural space, which is the space in your cat’s chest between the protective linings covering the lungs and the walls of the chest cavity itself. Normally, there is only a small amount of fluid in that area. Large amounts of fluid mean less room for the lungs to expand, which causes difficulty breathing and getting adequate oxygen to your cat’s body tissues.
Congestive heart failure accounted for about 40 percent of the cats with problems, followed by cancers at about 25 percent. Various infections and trauma accounted for most of the other cases.
Cats with heart failure had consistently lower body temperatures, so while this might be a quick screening test for cats with effusions, low body temperature can be caused by many health problems. If your cat presents at a veterinary hospital with an effusion, steps will be immediately taken to diagnose and treat the condition. A sample of the fluid will be drawn via a sterile needle aspirate through the chest wall. That sample will be evaluated for signs of infection or cancer. Additional fluid may be withdrawn to relieve some of the pressure on the lungs and help your cat to breathe more easily. Further treatments are customized to the cause of the effusion.
Unfortunately, the causes of pleural effusions in cats are often serious and may carry a poor prognosis.
Journal of the American Veterinary Medicine Association July 15, 2018