The first step of the investigations would be to remove the fluid for the diagnostic purpose. That will give clue for the causative organisms, by microscopic and biochemistry examination. Removing the fluid may serve therapeutic purpose too, giving relief for his symptoms. So first question needs to be asked what is the cause of the pneumonia (bacterial, viral or other). What would be the further care entail? Will he require some kind of support for breathing or will he be given oxygen? Total days of hospitalization, prognosis etc also needs to be ascertained from the doctors.
Hope this helps.
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Yes this makes the difference in treatment as specific bacteria have specific antibiotic sensitivity and different prognosis. The fluid around the heart can be pericardial fluid or pleural fluid. The pleural fluid is reactionary or part of the disease itself, while pericardial fluid (due to involvement of heart covering with the infection) may point out to a virulent bacteria which if not controlled early, may involve not only adjacent organs but distant organs and multiple organs too. That can complicate the situation.
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