Level 1 of 6Core
Community-acquired pneumonia: severity assessment and antibiotics
The core to-do list — diagnose and manage, at a glance
Diagnose— recognise it
- Pneumonia is a clinical AND radiographic diagnosis: a compatible history (cough, sputum, fever, dyspnoea) *plus* a new infiltrate on chest radiography — a febrile cough with a clear film is bronchitis. Physical examination is only 58% sensitive and 67% specific: a normal-sounding chest excludes nothing.
- Red flags whatever the outward composure: new confusion, respiratory rate ≥ 30/min, systolic BP ≤ 90 mmHg, SpO₂ < 92% on room air, hypothermia, frank haemoptysis, multilobar shadowing, rising lactate, exhaustion. Physiological reserve masks severity in the young — a 25-year-old with a rate of 34 and multilobar consolidation who is still conversing has severe pneumonia.
- Score CURB-65 for the admission decision: one point each for new Confusion, Urea > 7 mmol/L, Respiratory rate ≥ 30/min, BP systolic ≤ 90 or diastolic ≤ 60 mmHg, and age ≥ 65. Two findings override any score and mandate admission: room-air SpO₂ below 92%, and inability to maintain oral intake.Not available at your setup — Renal function (creatinine/urea). No urea available: score the remaining CRB-style criteria and let SpO₂ and oral intake drive the decision.
- Use the IDSA/ATS criteria — not CURB-65 or the PSI — for the critical care decision: either major criterion (invasive mechanical ventilation, or septic shock requiring vasopressors) mandates critical care; so do any three of nine minor criteria (rate ≥ 30, PaO₂/FiO₂ ≤ 250, multilobar infiltrates, confusion, urea ≥ ~7 mmol/L, white cells < 4000/µL, platelets < 100,000/µL, temperature < 36 °C, hypotension needing aggressive fluids).
- The elderly presentation is the one most often missed: new or worsening confusion, a fall, or decompensation of a chronic illness with no fever, no cough and no crackles — delayed treatment lets infection evolve rapidly.
- Children — count the respiratory rate for a full minute in a quiet child: fast breathing is ≥ 60/min under 2 months, ≥ 50/min at 2–11 months, ≥ 40/min at 1–5 years, ≥ 30/min over 5 years. Severe features: lower chest wall indrawing, grunting, head nodding, central cyanosis, SpO₂ < 90%, inability to drink, convulsions, lethargy, apnoea — in a young infant it is apnoea, not cough, that kills. CURB-65 does not apply to children.
Manage now— do this, in order
- Give empirical antibiotics as expeditiously as possible — no test delays the first dose: not a biomarker, not a sputum sample, not a radiograph. Mortality in hospitalised CAP correlates closely with timely administration.
- Oxygen to SpO₂ 94–98%, or 88–92% in known or suspected chronic type 2 respiratory failure; in children there is no hypoxic-drive concern — target 94–98% and never restrict oxygen in a hypoxic child.
- Outpatient, no comorbidity or resistance risk: amoxicillin 1 g orally three times daily plus a macrolide (azithromycin 500 mg day 1 then 250 mg daily for 4 days, or clarithromycin 500 mg twice daily) or doxycycline 100 mg twice daily; or doxycycline monotherapy; macrolide monotherapy only where local pneumococcal macrolide resistance is under 25%. Antibiotic use within the previous three months is the single most important risk factor for resistant pneumococci.Doctor / Nurse
- Inpatient, non-severe: a β-lactam (ceftriaxone 1–2 g IV daily, cefotaxime 1–2 g IV 8-hourly, or ampicillin–sulbactam 1.5–3 g IV 6-hourly) plus a macrolide (azithromycin 500 mg daily or clarithromycin 500 mg twice daily), or a respiratory fluoroquinolone alone (levofloxacin 750 mg or moxifloxacin 400 mg daily).Doctor / Nurse
- Severe CAP — a β-lactam alone is NOT adequate therapy: ceftriaxone 2 g IV daily plus a macrolide (observational data favour the macrolide), or a β-lactam plus a respiratory fluoroquinolone. Add MRSA cover (vancomycin 15 mg/kg IV 12-hourly adjusted to renal function and levels, or linezolid 600 mg 12-hourly) or *Pseudomonas* cover (piperacillin–tazobactam 4.5 g IV 6-hourly, cefepime 2 g 8-hourly, or meropenem 1 g 8-hourly) where that organism was isolated from the respiratory tract within the past year.Doctor / Nurse
- Daptomycin must never be used for pneumonia of any kind — pulmonary surfactant inactivates it.
- Supportive care: adequate hydration is therapeutic, not comfort care (dehydration suppresses sputum production) — balanced crystalloid to restore perfusion in shock, reassessed after each bolus, vasopressors for fluid-unresponsive shock; paracetamol 1 g 6-hourly (max 4 g/24 h) so the patient can cough and breathe deeply instead of splinting; thromboprophylaxis unless contraindicated. NIV frequently fails in pneumonia — a failed trial that delays intubation is dangerous.
- Paediatric antibiotics — weigh every child, never estimate: amoxicillin 45–90 mg/kg/day orally 8-hourly for non-severe pneumonia; ampicillin 200 mg/kg/day IV 6-hourly first-line in a previously well child; cefotaxime 75–225 mg/kg/day IV 8-hourly or ceftriaxone 50–75 mg/kg/day IV 12–24-hourly for severe illness; add vancomycin per local protocol in the critically ill child.Doctor / Nurse
- Treat a minimum of 5 days and until clinically stable, switching to oral when the patient can ingest and absorb the drug, is haemodynamically stable and improving. Sample a significant effusion in a septic patient — drainage is required if pH < 7.2, glucose < 2.2 mmol/L, LDH > 1000 U/L, bacteria are seen or cultured, or the fluid is frank pus; unrecognised empyema is the commonest reason an apparent treatment failure is not one. Reassess formally at about day 3; radiographic shadows take 4–12 weeks to clear — do not change antibiotics for a persistent shadow. Offer an HIV test to every patient with pneumonia.Doctor / Nurse
CURB-65 — 30-day mortality and disposal
| Score | Mortality | Action |
|---|---|---|
| 0 | 0.7% | Outpatient |
| 1 | 3.2% | Usually outpatient |
| 2 | 13.0% | Short stay / very close observation |
| 3 | 17.0% | Admit; consider critical care |
| 4–5 | 41.5–57.0% | Admit and refer for critical care |
SpO₂ < 92% on air or inability to maintain oral intake overrides any score.
Refer / escalate
Admit anyone with a CURB-65 of 2 or more, or with room-air SpO₂ below 92% or inability to maintain oral intake whatever the score, and refer immediately for critical care where either IDSA/ATS major criterion is present (invasive mechanical ventilation, or septic shock requiring vasopressors) or any three minor criteria are met — monitoring the borderline patient in critical care from the outset rather than waiting for deterioration on the ward.
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