A 46-year-old male patient is 2 days post-op for surgery to repair an aortic aneurysm. He is cur-rently receiving mechanical ventilation. Auscultation of the anterior and posterior chest reveals bilateral late inspiratory crackles

Percussion is dull in both lower lobes. A STAT radiograph reveals bibasilar infiltrates. The most likely cause of this patient's clinical presentation is which of the following?
a. Asthma
b. Pneumonia
c. Pneumothorax
d. Pleural effusion

ANS: B
Late inspiratory crackles and infiltrates on the chest X-ray are indicative of consolidation due to pneumonia. A patient having an asthma exacerbation would present with wheezing, hyperreso-nance on percussion, and increased radiolucency on X-ray. A patient with a pneumothorax would have unilateral absence of breath sounds, hyperresonance on percussion over the affected area, and lack of vascular markings over the affected area on X-ray. A pleural effusion manifests itself on X-ray as a blunting of the costophrenic angle on the affected side, a pleural friction rub just above the fluid level, and dullness to percussion over the pleural effusion.