HAP, VAP & aspiration pneumonia
HAP ≥48 h after admission; VAP ≥48 h after intubation. Cover PsA; add MRSA if risk (prior MRSA, IV abx 90 d, high local rates).
HAP and VAP
HAP starts ≥48 hours after admission. VAP starts ≥48 hours after intubation (/ATS, ). Diagnosis: new or progressive infiltrate plus 2 of 3 — fever, leukocytosis, purulent tracheal secretions. On the ventilator the differential includes atelectasis, ARDS, edema, and PE (VAE, not just VAP).
1
IV antibiotics in 90 days
The single most important MDRO risk factor. Recent drugs beat nursing-home labels.
2
Local ecology
Add MRSA and a second Gram-negative agent when local rates of MRSA or MDR GNR are >10%, or the patient has structural lung disease (CF, bronchiectasis) or prior MDRO.
3
VAP extras
Septic , ARDS, onset ≥5 days in hospital, or RRT before onset.
Micro: enteric GNR, MRSA/MSSA, Pseudomonas, Acinetobacter. About 1 in 5 is viral (Semin Respir ).
| Lane | Agents |
|---|---|
| Antipseudomonal β-lactams | Cefepime, ceftazidime, pip-tazo, meropenem. Aztreonam only for severe penicillin allergy. |
| Second Gram-negative (if high-risk Pseudomonas) | Levofloxacin / ciprofloxacin (local PsA susceptibility often only ~70–80%), tobramycin 5–7 mg/kg ×1 then levels, polymyxin B (call ID). De-escalate to monotherapy when cultures return. |
| Anti-MRSA | Vancomycin or linezolid. Daptomycin cannot treat pulmonary infection. |
- Workup: CXR, sputum culture, blood cultures, viral testing, MRSA swab. Induced sputum or BAL when the floor sample is junk.
- Daily toothbrushing cuts HAP (). Head of bed up, less sedation, extubate.
- On a ventilator ≥72 hours, 3 days of inhaled amikacin reduced VAP in AMIKINHAL ().
Aspiration: pneumonia vs pneumonitis
Micro-aspiration is common; “aspiration pneumonia” as a distinct bug list is overstated (). Large-volume events cause either chemical pneumonitis or bacterial pneumonia. Predisposition: AMS, dementia, esophageal dysmotility, post-obstruction, post-extubation, poor dentition, seizure, tube feeds.
Aspiration pneumonia
- GNRs and ordinary CAP/HAP organisms. Anaerobes are over-credited (; ).
- Indolent, putrid sputum, necrosis with cavity / abscess / empyema.
- Treat as CAP or HAP. Add anaerobes only for suspected abscess or empyema: amp-sulbactam if not severely ill, pip-tazo if sick, amox-clav outpatient. Alt: CTX + metronidazole, or clindamycin.
- Duration 7 days unless cavitary / abscess / empyema. Failure → image for a drainable collection.
Aspiration pneumonitis
- Chemical injury without infection. Abrupt (hours): low-grade fever, leukocytosis, hypoxemia, infiltrate (RML/RLL upright, RUL supine).
- Indistinguishable from pneumonia at the bedside in hour 1. Reassess — do not lock in 7 days of pip-tazo for a sandwich.
- No mortality benefit to prophylactic antibiotics after a witnessed aspiration ().
- Anaerobic respiratory cultures are low-yield; most labs will not run them.