Features to evaluate of a thoracentesis aspirate: specific gravity WCC and differential Protein and Glucose concentrations Lactate Dehydrogenase pH and pCO2 amylase Gram stain + cultures (+ AFB) exfoliative cytology ±rheumatoid factor (RF) ± complement (C3/C4) levels Pearls: low pH (< 7.20) – often indicates empyema probably requiring tube drainage very low glucose – rheumatoid … Continue reading Thoracentesis – What to Measure?