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.
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