In a patient with respiratory distress, which sign should lead you to suspect pleural effusion?

Diminished breath sounds are a significant indication that can suggest the presence of pleural effusion in a patient experiencing respiratory distress. When fluid accumulates in the pleural space, it can obstruct the normal transmission of breath sounds during auscultation. This is because the fluid dampens the sound waves produced by air movement in the lungs. As a result, localizing the source of diminished sounds can point to either a pleural effusion or other pathologies, but the presence of effusion is a key consideration.

In contrast, fever and chills typically indicate an infectious or inflammatory process, such as pneumonia, rather than directly pointing to pleural effusion. Cor pulmonale, which refers to right heart failure resulting from lung disease, is a consequence of chronic lung issues rather than a direct indicator of pleural effusion. Similarly, a productive cough can suggest pneumonia or bronchitis, but it does not specifically indicate pleural effusion. Therefore, among the choices provided, diminished breath sounds are the most direct clinical sign leading to a suspicion of pleural effusion.