Synopsis
Diagnose hospital-acquired or ventilator-associated pneumonia without mistaking colonisation or non-infective infiltrates for infection, obtain useful microbiology promptly, and start proportionate empirical therapy guided by severity and local resistance data.
- Hospital-acquired pneumonia develops 48 hours or more after admission and was not incubating at entry; ventilator-associated pneumonia usually begins more than 48 hours after endotracheal intubation.
- Require a compatible new clinical syndrome—fever or hypothermia, purulent secretions, inflammatory response, worsening gas exchange—and new or progressive radiographic infiltrate; no single sign proves VAP.
- Distinguish pneumonia from atelectasis, pulmonary oedema, aspiration pneumonitis, pulmonary embolism, acute respiratory distress syndrome, alveolar haemorrhage and ventilator-associated tracheobronchitis.
Key red flags
New or progressive infiltrate with worsening oxygenation, increased or purulent secretions and systemic inflammatory features after more than 48 hours of invasive ventilation; rising ventilator support is a severity marker.
Investigation priorities
Identify a new infiltrate and complications while comparing with prior films.
Management branches
Suspected HAP or VAP with new physiological deterioration.
- Perform ABCDE assessment, prescribe target-based oxygen, check the airway and ventilator circuit, obtain chest imaging and involve critical care early for shock or escalating support.
- Review admission timing, aspiration, recent procedures, fluid balance, antibiotics, prior cultures and resistance risks; search for non-pulmonary sepsis and common radiographic mimics.
Key medicines
Co-amoxiclav for low-resistance-risk HAPA typical NICE oral option is 500/125 mg three times daily for 5 days; use IV therapy if oral treatment is unsafe or severity requires it.
Piperacillin with tazobactamA common severe-infection regimen is 4.5 g IV every 8 hours, increased to every 6 hours in selected severe infection according to local policy and renal function.