What is the assessment and plan for Community-Acquired Pneumonia (CAP)?

Assessment and Plan for Community-Acquired Pneumonia (CAP)

The assessment and management of CAP should follow a systematic approach using severity assessment tools like CURB-65 or PSI to guide site-of-care decisions and empiric antibiotic therapy, with treatment tailored to likely pathogens based on patient risk factors.

Severity Assessment

Severity assessment is the cornerstone of CAP management and should be performed for all patients to guide appropriate treatment decisions 1.

Recommended Severity Assessment Tools:

• CURB-65 Score (preferred due to simplicity and possibly better outcomes 2)

  • Confusion
  • Urea >7 mmol/L (BUN >19 mg/dL)
  • Respiratory rate ≥30/min
  • Blood pressure (systolic <90 mmHg or diastolic ≤60 mmHg)
  • Age ≥65 years

• Scoring interpretation:

  • Score 0-1: Low risk (consider outpatient treatment)
  • Score 2: Moderate risk (consider short inpatient stay or supervised outpatient treatment)
  • Score 3-5: High risk (requires hospitalization, consider ICU for scores 4-5)

Additional Adverse Prognostic Features:

• Hypoxemia (SaO₂ <92% or PaO₂ <8 kPa) 1
• Bilateral or multilobar involvement on chest radiograph 1
• Presence of septic shock or need for mechanical ventilation 3

Management Plan Based on Setting

1. Outpatient Management (Low Risk)

• Empiric Antibiotic Therapy:

  • First choice: Amoxicillin (higher dose than previously recommended) 1
  • Alternative (for penicillin-allergic patients): Macrolide (erythromycin or clarithromycin) 1

• Supportive Care:

  • Rest and adequate hydration 1
  • Smoking cessation 1
  • Simple analgesia (e.g., paracetamol) for pleuritic pain 1
  • Follow-up within 48 hours or earlier if clinically indicated 1

2. Inpatient Management (Moderate to High Risk)

• Initial Assessment:

  • Oxygen therapy to maintain PaO₂ >8 kPa and SaO₂ >92% 1
  • Volume status assessment and IV fluids if needed 1
  • Regular monitoring of vital signs (at least twice daily) 1

• Empiric Antibiotic Therapy:

  • For non-severe hospitalized CAP: β-lactam (ceftriaxone, cefotaxime, ampicillin/sulbactam) plus a macrolide 1
  • Alternative: Antipneumococcal fluoroquinolone alone 1
  • First dose should be administered within 8 hours of hospital arrival 1

• Monitoring Response:

  • Monitor temperature, respiratory rate, pulse, blood pressure, mental status, and oxygen saturation 1
  • Repeat CRP measurement for patients not progressing satisfactorily 1
  • Consider repeat chest radiograph for patients not improving clinically 1

3. ICU Management (Severe CAP)

• Indications for ICU admission:

  • Respiratory failure requiring mechanical ventilation
  • Septic shock requiring vasopressors
  • Two or more of: systolic BP <90 mmHg, multilobar involvement, PaO₂/FiO₂ <250 3

• Management:

  • Should be managed by specialists with appropriate training in intensive care and respiratory medicine 1
  • Antibiotic therapy: β-lactam plus either a macrolide or fluoroquinolone; consider dual antipseudomonal agents in at-risk patients 1
  • Consider bronchoscopy to remove secretions, obtain samples, and exclude endobronchial abnormality 1

Diagnostic Testing

• Outpatient setting:

  • Chest radiograph to confirm diagnosis 1
  • Limited additional testing unless severe disease suspected

• Inpatient setting:

  • Complete blood count, blood chemistry, blood cultures (before antibiotics)
  • Sputum Gram stain and culture
  • Pulse oximetry or arterial blood gas analysis
  • Consider legionella urinary antigen testing in severe CAP or during outbreaks 1
  • Consider pneumococcal antigen tests for patients with severe CAP 1

Follow-up Plan

• Clinical review for all patients at approximately 6 weeks 1
• Chest radiograph at follow-up for patients with:
  • Persistent symptoms or physical signs
  • Higher risk of underlying malignancy (especially smokers and those over 50 years) 1
• Further investigations (including bronchoscopy) for patients with persisting signs, symptoms, and radiological abnormalities at 6 weeks 1

Common Pitfalls to Avoid

1. Overdiagnosis of CAP - Studies show up to 38% overdiagnosis rate 4
2. Underutilization of severity scores - Documentation rates as low as 7% 4
3. Delayed antibiotic administration - First dose should be given within 8 hours of hospital arrival 1
4. Inadequate follow-up - Arrange clinical review at 6 weeks for all patients 1
5. Unnecessary hospitalization - 50-78% of CAP patients may be admitted unnecessarily 4

Prevention Strategies

• Pneumococcal and influenza vaccination for at-risk populations 1
• Smoking cessation counseling 1
• Nutritional support for prolonged illness 1