PLEURAL INFECTION AND EMPYEMA

• Take history, clinical examination and chest X-ray
• If a pleural effusion with no evidence of infection, see Investigation of a pleural effusion guideline

• Involve respiratory physician
• Diagnostic pleural aspiration under ultrasound guidance
• Treatment is both drainage of the infected pleural fluid and antimicrobials

Appearance of aspirated fluid

Fluid aspirated is pus

• Send samples for M, C&S
• Insert chest tube – see Intercostal tube drainage guideline

Fluid aspirated is not pus

• Send samples for: cytology, protein, LDH, glucose, pH, Gram stain, culture and sensitivity and TB cultures
• take blood at same time for LDH, protein and glucose
• If chylothorax suspected, send samples for cholesterol and triglyceride and for centrifuging
• If haemothorax suspected, send sample for haematocrit
• If rheumatoid disease suspected, send samples for glucose and complement
• If pancreatitis suspected, send sample for amylase

Failed aspiration or effusion too small to sample

• Consider CT scan and further image-guided aspiration

Result of pleural fluid microscopy

Gram stain and/or culture positive and/or pH <7.2

Infection

• Insert chest tube – see Intercostal tube drainage guideline

Both Gram stain and culture negative and pH ≧7.2

Pleural fluid aspiration non-diagnostic

• Check if other diagnosis. See Investigation of a pleural effusion guideline
• Unless clinical indication for chest tube, observe
• If poor clinical response, repeat chest imaging and consider repeat fluid sampling

See Original Flowchart

Antimicrobial therapy

• Unless absolutely impossible, send sample of fluid for culture before starting antimicrobial therapy
• If microbe known, follow advice of microbiologist / ID consultant
• Otherwise start empirical therapy while awaiting results of culture

Infection Control alerts

• Check for IC alert
• if IC alert not available, check previous 12 months of microbiology reports
• If MRSA present, treat as tagged for MRSA. See MRSA management
• if ESBL, MGNB, CARB present, treat as tagged for ESBL. See ESBL/MGNB/CARB management

Penicillin Allergy

• True penicillin allergy is rare
• Ask the patient and record what happened when they were given penicillin
• If any doubt about whether patient is truly allergic to penicillin, seek advice from a microbiologist or consultant in infectious diseases

Empirical antimicrobial regimen

• First line: Co-amoxiclav 1.2 g IV 8-hrly
• Alternative (true penicillin allergy): Levofloxacin 500 mg IV by infusion 12-hrly plus metronidazole 500 mg IV by infusion/or 400 mg oral 8-hrly
• if patient tagged for MRSA, add vancomycin IV by infusion (see Vancomycin guideline and calculator)
• if MRSA proven (cultured in pleural fluid) or likely cause of empyema (e.g. recent relevant specimen other than pleural fluid positive for MRSA): Discuss use of additional antimicrobial (e.g. rifampicin) with microbiologist/ID Consultant

• Nutritional support in prolonged illness

Management of chest drain

• Ensure chest tube is draining freely and the tube is swinging at all times.
• For small bore (12–18F) catheters, use the 3-way tap to flush with sodium chloride 0.9% 30 mL every 6 hr if not draining freely
• No flushing required for larger bore drains

Removal of tube

• When the patient better with:
• infection improved and
• CXR showing fluid drained almost completely

Oral antimicrobials

• Change to oral as soon as clinical improvement occurs and temperature normal for 24 hr
• providing there is no contra-indication to oral therapy and sensitivities allow
• Use oral antimicrobial to which microbe sensitive with good tissue penetration
• if not known or in doubt, discuss with microbiologist or consultant in infectious diseases

Duration of antimicrobials

• At least 3 weeks: continue antimicrobial therapy for a prolonged period of time
• usually at least until all fluid has gone and drain has been removed
• Monitor patient closely for recurrence after stopping treatment

Failure to respond to therapy

• Review by respiratory consultant/consultant in infectious diseases
• Repeat Chest X-ray
• Check tube, fluid drainage, and consider CT scan
• Consider large bore chest tube
• Review antimicrobials when culture results become available
• Early liaison with thoracic surgeons

• Discharge when chest drains removed and clinical variables stable
• Continue antimicrobials for at least 3 weeks after initiation
• Follow all up patients in respiratory clinic with Chest X-ray about 3–4 weeks after discharge