EMPYEMA THORACIS

DEFINITION

• Fischer's Mastery of Surgery, 8th ed.
• Sabiston Textbook of Surgery

ETIOLOGY / PATHOGENESIS

• Gram-positive: S. pneumoniae, S. aureus, beta-hemolytic streptococci
• Gram-negative aerobes: E. coli, Klebsiella, Pseudomonas
• Anaerobes: Fusobacterium nucleatum, Prevotella spp., Bacteroides fragilis (especially in aspiration, alcoholism, periodontal disease)
• Polymicrobial cultures present in up to 50% of cases
• Cultures may be sterile if antibiotics were started before culture
• Fishman's Pulmonary Diseases and Disorders

THREE STAGES OF EMPYEMA

• Fischer's Mastery of Surgery, 8th ed.
• Schwartz's Principles of Surgery, 11th ed.

CLINICAL FEATURES

• Fever, chills, rigors (constitutional)
• Chest pain (pleuritic - sharp, worse on breathing)
• Dyspnoea, cough (often productive if underlying pneumonia)
• Weight loss, malaise, anorexia (in chronic cases)

• Tachycardia, tachypnoea
• Dullness to percussion over affected area
• Reduced/absent breath sounds
• Reduced chest expansion on affected side
• Intercostal fullness may be present
• In chronic empyema: scoliosis toward affected side, chest wall retraction, clubbing

INVESTIGATIONS

• Raised TLC (neutrophilia), raised ESR, raised CRP
• Blood cultures (bacteremia may be present)
• Low albumin in chronic cases

• Appearance: turbid, frankly purulent
• WBC >25,000/mL with neutrophil predominance
• Glucose <30 mg/dL (empyema) - low due to bacterial metabolism
• pH <7.2 (exudate)
• LDH >1000 U/L
• Gram stain and culture (aerobic, anaerobic, AFB, fungal)
• Protein, LDH (Light's criteria for exudate)

• CXR: Homogeneous opacity, blunting of costophrenic angle; D-shaped opacity suggests loculation; mediastinal shift away from affected side
• CT chest (investigation of choice): Confirms diagnosis, shows loculations, pleural thickening, "split pleura sign" (enhancement of both pleural layers), underlying lung pathology

• Ultrasound: Confirms fluid, guides drainage; internal echoes/septations indicate fibrinopurulent stage

MANAGEMENT

A. General / Medical Measures

1. Antibiotics (systemic, not intrapleural): Broad spectrum empirically covering gram-positive, gram-negative, and anaerobes
   • e.g., Piperacillin-tazobactam / Meropenem + Metronidazole (for anaerobes)
   • Modify based on culture and sensitivity
   • Duration typically 3-6 weeks
2. Nutritional support, physiotherapy, analgesics

B. DRAINAGE PROCEDURES

1. Thoracentesis (Aspiration)

• Used in Stage I (exudative phase) when fluid is thin and free-flowing
• Simple needle aspiration - adequate for early parapneumonic effusions
• Complete drainage + lung re-expansion confirms adequacy

2. INTERCOSTAL TUBE DRAINAGE (Closed Chest Drainage / ICD)

• Stage I-II empyema (fibrinopurulent phase)
• Frankly purulent or rapidly accumulating fluid
• Bronchopleural fistula with empyema
• Loculated fluid unresponsive to thoracentesis

• Patient positioned semi-recumbent or lateral
• Site: usually 5th-6th intercostal space, mid-axillary line (or ultrasound-guided)
• Local anaesthesia; incision over upper border of rib below (to avoid neurovascular bundle)
• Blunt dissection through intercostal muscles; finger sweep to confirm pleural cavity
• Large-bore chest tube (28-32 Fr) inserted; directed posteriorly and basally
• Connected to underwater seal drainage (Bülau drain) ± suction (-20 cmH₂O)
• Tube removed when: drainage <100-200 mL/day, lung expanded on imaging, infection resolving

• tPA (10 mg) + DNase (5 mg): instilled via chest tube, clamped 1-2 hours, drain released; position changes every 15 minutes; repeated daily for 3-5 days
• Reduces viscosity, breaks down fibrin loculations
• Combination more effective than either alone
• Reduces need for surgical intervention; reduces hospital stay by ~7 days
• Schwartz's, Fischer's

• Lung fails to re-expand
• Persistent fever >48-72 hours
• Drainage >200 mL/day beyond 7 days
• CT shows inadequate drainage/loculations
• Fishman's Pulmonary Diseases

3. RIB RESECTION (Open Drainage / Drainage via Rib Resection)

• Chronic/organized empyema where chest tube drainage fails
• When closed drainage is ineffective and patient is unfit for thoracotomy
• As a temporizing measure before definitive surgery

1. Patient under GA or local anaesthesia
2. A 5-7 cm segment of the rib overlying the most dependent part of the empyema cavity is resected (usually 8th or 9th rib posterolaterally)
3. Periosteum is stripped; rib excised with rib shears
4. Underlying parietal pleura entered; pus drained
5. Cavity washed with saline/antiseptic
6. A large-bore tube/drain placed in the cavity and kept open (not connected to underwater seal)
7. Cavity is packed and managed with daily dressings until it gradually obliterates
8. Skin closure delayed (secondary intention)

• Fishman's, Schwartz's

4. DECORTICATION

• Stage III (organized/chronic) empyema with thickened visceral pleura
• "Trapped lung" - lung encased by fibrous peel and unable to expand
• Failed chest tube drainage with persistent pleural infection
• Restrictive physiology from fibrous pleural peel

• Posterolateral thoracotomy (standard) OR
• VATS (Video-Assisted Thoracoscopic Surgery) in selected early-stage cases

1. Posterolateral thoracotomy through 5th or 6th intercostal space
2. Empyema cavity entered; pus and debris evacuated
3. The thick fibrous peel (cortex) overlying the visceral pleura is carefully dissected free using a Cobb elevator, gauze swabs, and sharp dissection
4. Both parietal cortex (from chest wall) and visceral cortex (from lung surface) are removed
5. Care is taken NOT to damage the underlying visceral pleura (which would cause air leak)
6. Lung is inflated intraoperatively to confirm full expansion
7. Chest drains placed; chest closed in layers

• Bailey & Love's Short Practice of Surgery, 28th ed.
• Fischer's Mastery of Surgery, 8th ed.

5. WINDOW OPERATION (Thoracostomy Window / Eloesser Flap)

• Chronic empyema in debilitated/frail patients unfit for thoracotomy
• Empyema with bronchopleural fistula post-pneumonectomy (where definitive surgery is too risky)
• Failed or recurrent empyema after rib resection drainage
• As a palliative/temporizing procedure to allow healing

1. Segments of 2-3 ribs (usually 2-3 cm each) overlying the empyema are resected
2. The skin is fashioned into a U-shaped or tongue flap that is sutured to the parietal pleura, creating a permanent cutaneous opening (the "window")
3. The cavity is packed with gauze/Betadine soaked dressings
4. Daily dressing changes allow the cavity to gradually granulate inward
5. Once the cavity is clean and the bronchopleural fistula (if present) heals, the window can be formally closed - often with a muscle flap (e.g., latissimus dorsi, serratus anterior, or omentum)

• Applicable in high-risk patients
• Does not require general anaesthesia
• Converts life-threatening infection to a manageable chronic wound

• Fishman's Pulmonary Diseases and Disorders (Eloesser flap described)
• Schwartz's Principles of Surgery, 11th ed.

SUMMARY TABLE - SURGICAL PROCEDURES FOR EMPYEMA

COMPLICATIONS OF EMPYEMA

• Bronchopleural fistula - pus enters bronchial tree
• Pneumothorax (if BPF develops)
• Empyema necessitatis - pus burrows through chest wall, presents as subcutaneous swelling
• Osteomyelitis of ribs
• Septicaemia
• Fibrothorax - complete fibrotic obliteration of pleural space
• Scoliosis (in children, from chronic empyema)
• Restrictive lung disease from trapped lung

MORTALITY

• Ranges from 1% in healthy patients to >40% in immunocompromised patients
• Death often reflects severity of underlying comorbidity
• Schwartz's Principles of Surgery, 11th ed.