Empyema
Empyema is inflammatory fluid and debris in the pleural space
Causes
-Parapneumonic 70%
-Thoracic trauma (About 1-5% of cases of thoracic trauma lead to an empyema.)
-Rupture of a lung abscess into the pleural space
-Extension of a non–pleural-based infection (eg, mediastinitis, abdominal infection)
-Esophageal tear
-Iatrogenic introduction at the time of thoracic surgery
-An indwelling catheter that is a nidus for infection
pathophysiology
1-Exudative stage: Protein-rich pleural fluid remains free flowing. The number of neutrophils is rapidly increasing. Glucose and pH levels are normal. Drainage of the effusion and appropriate antimicrobial therapy are normally sufficient for treatment.
2-Fibrinolytic stage: Viscosity of the pleural fluid increases. Coagulation factors are activated, and fibroblastic activity begins coating the pleural membrane with an adhesive meshwork. Glucose and pH levels are lower than normal.
3-Organizing stage: Loculations form. Fibroblastic activity causes adherence to the visceral and parietal pleura. This activity may progress with the formation of pleural peels in which the pleural layers are indistinguishable. Pus, which is a protein-rich fluid with inflammatory cells and debris, is present in the pleural space. Surgical intervention is often required at this stage
1. Exudate stage:
1. Protein-rich pleural fluid remains free flowing.
2.The number of neutrophils is rapidly increasing.
3.Glucose and pH levels are normal.
4 Drainage of the effusion and appropriate antimicrobial therapy are normally sufficient for treatment
2-Fibrinolytic stage:
1.Viscosity of the pleural fluid increases.
2.Coagulation factors are activated, and fibroblastic activity begins coating the pleural membrane with an adhesive meshwork.
3.Glucose and pH levels are lower than normal
3-Organizing stage:
1.Loculations form.
2.Fibroblastic activity causes adherence to the visceral and parietal pleura. This activity may progress with the formation of pleural peels in which the pleural layers are indistinguishable.
3.Pus, which is a protein-rich fluid with inflammatory cells and debris, is present in the pleural space.
Surgical intervention is often required at this stage
Presentation:
-chills, high-grade fever, sweating, poor appetite, malaise, and cough
-Pleurisy and dyspnea
-dullness to percussion and absent breath sounds
Investigations:
Standard 2-view chest radiography
Ultrasonography
Chest CT
Intrvention:
The main clinical decision is determining the appropriate time to drain the empyema
Laboratory indications for consideration of drainage are the following:
pH < 7.20
Glucose < 60 mg/dL
LDH > 600 IU/L
Bacteria on Gram staining
earliest stages:
thoracentesis
small-bore catheter
Chest tube
Surgical interventions:
-Thoracoscopic debridement
-Video-assisted thoracoscopic surgery (VATS)
-Open thoracotomy for debridement
-Open surgical decortication