These include cardiac puncture or coronary vessel laceration, liver or stomach laceration, pneumothorax, hemothorax, pneumoperitoneum, pneumopericardium, suppurative pericarditis
[jove.com]
This can cause uncomfortable pressure on the heart and chest as well as dyspnea (shortness of breath) and coughing.
[asbestos.com]
Usually within 10 days for mose cases of neoplasia (eg hemangiosarcoma Pericardium: hemangiosarcoma ). Prognosis following repeated drainages is less good.
[vetstream.com]