Pleural effusion

A pleural effusion is a life threatening condition where fluid, generally from the lymphatic system, but occasionally blood, drains into the empty cavity between the lungs and the ribcage. As a result, the lung cannot expand into the cavity and the patient becomes unable to breathe.
Treatment is to withdraw the fluid with a large needle and a syringe, but if the condition continues, this must be done frequently. As such, it's important to establish the underlying condition that is causing the fluid to fill the cavity.
Pleural effusion at Wikipedia
Category:Symptoms