Review Question - QID 109319

This patient is presenting after a trauma with decreased breath sounds, and a chest radiograph showing a pleural effusion and rib fractures, suggesting the diagnosis of hemothorax, which would show a protein pleural fluid to serum ratio of > 0.5.

Hemothorax is the accumulation of blood in the pleural cavity. The patient often presents following thoracic trauma such as after a motor vehicle accident, gun-shot, or knife wound. Signs and symptoms may include flat neck veins (secondary to hypovolemia), a deviated trachea, decreased breath sounds, and dullness to percussion. Pleural fluid analysis would show a grossly red exudate (i.e., protein pleural fluid to serum ratio > 0.5, lactate dehydrogenase (LDH) pleural fluid to serum ratio > 0.6, LDH > 2/3 upper limits of normal for serum LDH) with a hematocrit that exceeds half the simultaneous peripheral blood hematocrit.

Figure A shows a chest radiograph with broken ribs and a fluid accumulation in the left pleural space, likely a hemothorax.

Incorrect Answers:
Answer 1: Grossly black pleural fluid can be seen with Aspergillus niger infections, metastatic melanoma, non-small cell lung cancer, or a ruptured pancreatic pseudocyst. It can also be seen with a chronic hemothorax, but an acute hemothorax following trauma would appear red/bloody.

Answer 2: Lymphocyte count of > 90% of total WBC can be seen in tuberculosis or lymphoma.

Answer 3: Presence of amylase may suggest the presence of pancreatic disease, esophageal rupture, or malignancy.

Answer 5: Triglycerides > 110 mg/dL indicates a chylothorax. This is most commonly caused iatrogenically or it can seen in association with lymphoma. This patient’s clinical presentation is more consistent with a hemothorax.

Bullet Summary:
Hemothorax presents with trauma to the chest, reduced breath sounds, dullness to percussion, and possibly flat neck veins and tracheal deviation.