Empyema

Abstract

Empyema thoracis is defined as a collection of pus in the pleural space. It exists in three phases. The exudative, acute phase is characterized by low viscosity fluid with a low cell count, low WBC count, low LDH, and normal glucose and pH. The lung is easily expandable after removal of the fluid. The fibrinopurulent, intermediate phase has turbid fluid with increased WBC, high LDH, low glucose and pH. There is fibrin deposition on both pleural surfaces that forms a confining peel that traps the lung. The organizing, chronic phase shows organization of the peel with ingrowth of capillaries and fibroblasts. The fluid is viscous with a pH < 7, glucose <40, and begins at ~ 7–10 days and is completed by 4–6 weeks.