ICU Chest Films > Fluid in the Chest > Pleural Effusions > Pleural Effusions at the Apex

Pleural Effusions at the Apex

Fluid in the apex, in a supine patient, is more easily identified. A large pleural effusion may appear as a pleural cap with fluid occasionally collecting on the medial side, appearing as a widened mediastinum. Even with optimal radiographic techinique, small pleural effusions are difficult to identify in the supine patient.

How much fluid must accumulate before you expect to see changes in the supine patient's chest x-ray?
5 ml
50 ml
> 500 ml

A large pleural effusion has wrapped around the lateral and apical lung surfaces.