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Hospital Cases  > Medical  > Pyothorax
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This is an uncommon but very serious illness. Basically, its an abscess that has formed inside the chest cavity i.e. the lungs and heart are surrounded by a pool of pus. It is seen in cats following a cat bite that has punctured the chest cavity, and in dogs who have swallowed a sharp foreign body (e.g. grass seed) that has penetrated the oesophagus and ended up in the chest cavity.

Felix was presented with a history of lethargy and inappetence for the last week. His coat was dull and his breathing shallow and rapid. His temperature was elevated and his gums were very pale. When we tapped on his chest with a finger, it had a very dull sound instead of an hollow sound.

X-rays revealed the presence of fluid inside the chest (hydrothorax). We initially suspected bleeding into the chest from an injury or possible rodenticide poisoning which would explain the pale gums.

After sedating Felix with a pain killer and a touch of sedative, we inserted an 20 gauge 1" long IV catheter into the right chest cavity. We removed approx 60mls of smelly pus. We repeated the procedure on the left chest using a 14 gauge 3" IV catheter in which we made some additional small drainage holes in. We removed a further 60mls of pus from the chest with the bigger catheter. We sutured this catheter to the chest wall and placed a bandage over the whole chest.

The chest was flushed with 240mls of warmed saline, using 60mls at a time, and rolling the cat whilst the 60mls was inside the chest cavity. Eventually, the fluid we suctioned back was much less thicker and had less pus present. Finally, we placed a whole vial of Benzyl penicillin in 10msl of saline into the chest cavity and left it in place. Felix was placed on an IV drip and given some analgesics and an antibiotic injection (Clavulox)

The gum colour improved immediately so we suspect his pale gums were due to compression of the lungs by the pus. The lungs could not expand so the blood was not circulating to them and getting fresh oxygen in it.

Over the next 36 hours, we repeated the flushing and instillation of benzyl penicillin twice a day. By 48 hours, we could only remove 10mls of fluid so we decided to remove the catheter as it could possibly act as a continued source of infection itself.

At this stage, Felix was sitting up, eating and stared to groom himself. As soon as his strength returned, we added Flagyl tablets to the treatment to deal with any anaerobic (none-oxygen loving) bacteria inside the chest cavity.

It is hoped the abscess has been treated sufficiently and that there will be no re-occurrence. Felix was sent home on 3 weeks of antibiotic to be sure.

Repeat x-rays at 5 days showed only a small amount of fluid in his chest. The lungs were fully expanded and we could see the outline of the heart. He was eating well and very content with lots of purring when handled.

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