Aspiration pneumonia and pneumonitis

Background

• Difficult to predict which pts with pneumonitis will go on to develop PNA
• Aspiration pneumonitis
  • Inflammatory chemical injury of tracheobronchial tree and pulmonary parenchyma
    • Due to inhalation of regurgitated sterile gastric contents
      • Must aspirate at least 20-30mL of gastric contents with pH <2.5
    • Can lead to aspiration PNA d/t pulmonary defense mechanism injury
• Aspiration pneumonia
  • Alveolar space infection d/t inhalation of pathogenic material from oropharynx
    • Increased in pts w/ periodontal dz, chronic colonization of upper airways, PPI/H2 meds
  • Accounts for up to 20% of CAP in elderly, majority of nursing home-acquired PNA
  • Microbiology
    • Community acquired: Pneumococcus, staph, H flu, enterobacter
    • Hospital acquired: Pseudomonas, gram-negatives

Diagnosis

• Aspiration pneumonitis
  • Cough, tachypnea, bloody sputum, respiratory distress
• Aspiration PNA
  • Fever, dyspnea, productive cough, Tachypnea, tachycardia, AMS
  • CXR
    • Unilateral focal or patchy consolidations in dependent lung segments
      • Right lower lobe is most common area; bilateral patterns can also be seen

Work-Up

• CXR

Treatment

• Aspiration pneumonitis
  • Suction upper airway if aspiration is witnessed
  • Abx
    • Only recommended if symptoms persist >48hr
      • Levo/moxifloxacin or clindamycin or amoxicillin-clavulanate
• Aspiration pneumonia
  • Community-acquired
    • Moxifloxacin or clinda or amoxicillin-clavulanate
  • Health care-associated or periodontal disease or alcoholism
    • CTX + clindamycin OR
    • Piperacillin-tazobactam + clindamycin OR
    • Ampicillin-sulbactam + clindamycin OR
    • Cefepime + clindamycin OR
    • Levofloxacin + clindamycin

Disposition

• Healthy person
  • Observe for 1hr; if asymptomatic discharge
  • If mild-moderate symptoms develop and persist >48hr treat with antibiotics
• Chronically ill or nursing home pt
  • Consider ED obs unit versus short admission for observation +/- prophylactic abx
• Admit all pts w/ aspiration PNA

See Also

Pneumonia (Main)

Source

Tintinalli