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The mortality of pleural effusion depends on various factors such as underlying cause, patient's overall health, and timely treatment. In general, if pleural effusion is treated promptly and effectively, the mortality rate is low. However, severe or untreated cases can lead to complications such as respiratory failure and sepsis, which can increase mortality risk.

To increase oxygenation/ventilation of the unaffected lung

The pleural effusion is any abnormal amount of fluid all around the lungs. It can result to varying types of medical conditions.