Q: 42 year old male is admitted to ICU with community acquired pneumonia. CXR showed significant unilateral pleural effusion. You decided to perform diagnostic pleural tap to send fluid for culture and sensitivity to guide antibiotic drainage. Initial report from lab showed PH of 7.14 of pleural fluid. What is your next step?  

 

Answer: Chest tube placement 

As famously known: “the sun should never set on a parapneumonic effusion”, PH lower than 7.20 of pleural fluid is the most powerful indicator to predict the need for chest tube drainage in patients with non-purulent, culture negative fluid.

Reference:

1.  Heffner JE, Brown LK, Barbieri C, DeLeo JM. "Pleural fluid chemical analysis in parapneumonic effusions. A meta-analysis". American Journal of Respiratory Critical Care Medicine 1995; 151(6):1700-8

2. Sahn SA, Light RW. The sun should never set on a parapneumonic effusion. Chest 1989;95:945-7.