Pneumonia Management Guide: CAP, HAP, and VAP Diagnosis and Treatment

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🏥 Part 1: Community-Acquired Pneumonia (CAP)

🔍 Diagnostic Criteria

• Cough, fever, dyspnea, pleuritic chest pain

• Physical findings: rales, bronchial breath sounds, dullness to percussion

• Imaging: new infiltrate on chest X-ray
  

🧪 Severity Assessment (to guide IPD vs OPD)

• CURB-65:

• Confusion

• Urea > 7 mmol/L

• Respiratory rate ≥ 30

• Blood pressure (SBP < 90 or DBP ≤ 60 mmHg)

• Age ≥ 65
  

Score ≥2 → consider hospitalization

💊 Empiric Antibiotic Therapy (IDSA/ATS 2019)

A. Outpatient Treatment

1. Healthy patient, no recent antibiotics:

   • Amoxicillin 1 g TID PO

   • Doxycycline 100 mg BID PO

   • Macrolide (Azithromycin 500 mg Day 1, then 250 mg daily × 4 days) if local resistance <25%

2. Comorbidities (DM, CHF, COPD, CKD, etc.):

   • Amoxicillin-clavulanate 875/125 mg BID PO or cefpodoxime 200 mg BID PO

   • PLUS macrolide or doxycycline

   • Or monotherapy: Levofloxacin 750 mg PO daily or Moxifloxacin 400 mg PO daily

B. Inpatient (Non-ICU)

• Ceftriaxone 1-2 g IV q24h + Azithromycin 500 mg IV/PO q24h

• Or Levofloxacin 750 mg IV/PO daily

C. ICU Treatment

• Ceftriaxone 2 g IV q24h + Azithromycin 500 mg IV q24h

• Or Ceftriaxone + Levofloxacin
  

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🏨 Part 2: Hospital-Acquired Pneumonia (HAP)

Definition:

• Occurs ≥48 hours after hospital admission without prior mechanical ventilation.

Risk Stratification:

• Low risk for MDR pathogens: No prior IV antibiotics in past 90 days

• High risk: Prior IV antibiotics, structural lung disease, or septic shock

Empiric Treatment:

1. Low risk for MDR:

   • Piperacillin-tazobactam 4.5 g IV q6h

   • Or Cefepime 2 g IV q8-12h

2. High risk/MDR suspicion:

   • Antipseudomonal β-lactam: Meropenem or Cefepime

   • PLUS anti-MRSA: Vancomycin 15 mg/kg IV q12h or Linezolid 600 mg IV q12h

   • Add second antipseudomonal agent if septic shock or >10% resistance
     

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🛏️ Part 3: Ventilator-Associated Pneumonia (VAP)

Definition:

• Occurs ≥48-72 hours after endotracheal intubation

Pathogens to Cover:

• MRSA, Pseudomonas aeruginosa, ESBL GNB, Acinetobacter spp.

IDSA 2016 Empiric Regimens:

• 1 anti-MRSA agent:

  • Vancomycin or Linezolid

• 2 anti-pseudomonal agents from different classes:

  • β-lactam (e.g., meropenem, cefepime, piperacillin-tazobactam)

  • Non-β-lactam (e.g., ciprofloxacin, levofloxacin, or aminoglycoside like amikacin)

Duration:

• Typically 7 days (can be adjusted by clinical response)
  

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🧼 Additional Management Steps

• Oxygen therapy (maintain SpO₂ > 92%)

• Fluids and antipyretics (e.g., paracetamol)

• Monitor vitals and oxygenation

• Sputum culture and blood cultures before antibiotics

• Consider Legionella urinary antigen and influenza testing in CAP

Would you like me to continue into Thai CPG adaptation, summarize these for OSCE pattern, or help simulate a case-based management?