Synopsis
Diagnose pneumonia clinically and radiographically where appropriate, use CRB65/CURB65 plus judgement to select care, and give severity-matched antibiotics, oxygen and adjunctive treatment with explicit review points.
- CAP is an acute lower respiratory infection acquired outside hospital with compatible clinical features and, in hospital, usually new radiographic shadowing not explained by another cause.
- Assess ABCDE, SpO2, sepsis physiology, ability to take oral medicines, frailty/comorbidity and social support before scoring severity.
- CRB65 in the community and CURB65 in hospital support risk assessment: Confusion, urea above 7 mmol/L, respiratory rate at least 30/min, low BP, age 65 or over; each scores 1.
Key red flags
CURB65 3-5 and/or clinical shock, profound hypoxaemia, rapid progression or need for ventilatory/vasopressor support. Seek critical-care input early and treat promptly.
Investigation priorities
Estimate mortality risk and guide place/intensity of care.
Management branches
Suspected CAP with systemic illness or hospital presentation.
- ABCDE, SpO2, sepsis assessment and CRB65/CURB65; obtain CXR and relevant cultures promptly without delaying antibiotics in unstable disease.
- Give oxygen to 94-98%, or 88-92% if hypercapnic risk. Give oral antibiotic first if feasible; use IV when high severity, vomiting, absorption concern or critical illness requires it.
Key medicines
Amoxicillin500 mg orally three times daily for 5 days; higher doses may be used for severe infection according to BNF/renal function.
Doxycycline200 mg orally on day 1, then 100 mg once daily on days 2-5.