Pleural effusion visualized from the apical window
These images were obtained from a patient with acute kidney injury requiring renal replacement therapy. In the apical view, you can see a large anechoic area beside the left heart = left pleural effusion. Presence of collapsed lung is a clue that the effusion is around the lung. In poor quality images, this can be confused with pericardial effusion.
Take home point: Get used to appreciating pleural and pericardial effusions in multiple views. Not all patients have every scanning window available (due to body habitus, surgical dressings/drains etc.) Presence of collapsed lung is a big clue for pleural effusion in any view.
Another interesting thing to note in this context: If this patient becomes hypotensive during dialysis, think of left pleural effusion causing tamponade effect. During ultrafiltration, venous return/ intra-cardiac pressure drops. In a patient with low intravascular volume, extra-cardiac pressure due to pleural effusion might cause a drop in cardiac output in this scenario.
Below image obtained from a patient with CKD and hypervolemia demonstrates both pericardial and pleural effusions seen from the apical window (more lateral probe position).