– A lung infection caused by inhaling foreign materials like food, liquids, or vomit into the lungs
– Leads to inflammation and infection primarily affecting the lower respiratory tract

– Occurs when foreign material enters the lungs causing inflammation and infection
– Results from the aspiration of stomach contents or oropharyngeal secretions into the lower respiratory tract
– Can lead to inflammation, infection, and lung damage
– Healthy individuals have defense mechanisms like cough and lung cilia to remove small aspirated particles
– Common sites: Typically affects the apical and posterior segments of the lower lobe of the right lung
– Positional impact: The supine position can involve the posterior segment of the upper lobes in aspiration events

– Inhalation of gastric contents: Acid reflux, vomiting
– Aspiration of oral secretions: Impaired swallowing, decreased consciousness
– Aspiration of foreign bodies or other substances

Community-Acquired:
– Streptococcus pneumoniae
– Staphylococcus aureus
– Haemophilus influenzae
– Klebsiella pneumoniae (especially in alcohol misuse)
Nosocomial:
– Oral anaerobes
– Gram-positive cocci (Peptostreptococcus spp., Peptococcus spp.)
– Gram-negative bacilli (Enterobacteria, Pseudomonas aeruginosa)
– Meticillin-resistant Staphylococcus aureus (MRSA)

– Chemical Pneumonitis: Irritation of the lungs that may progress to acute respiratory distress syndrome (ARDS) and bacterial infection, occurring as a complication of aspiration pneumonia.

– Respiratory Complications: Empyema, lung abscess, respiratory failure, and lung injury.

– Most commonly affected: Apical and posterior segments of the lower lobe of the right lung
– In supine position: Posterior segments of the upper lobes may be involved.

Impaired Consciousness:
– Drug or alcohol misuse
– General anesthesia
– Seizures
– Sedation
– Acute stroke
– Central nervous system lesions
– Head injury
Other Factors:
– Poor mobility
– Nil by mouth status
– Increasing age
– Chronic obstructive pulmonary disease (COPD)
– Male gender
– Increasing number of medications
Swallowing Disorders:
– Oesophageal stricture
– Dysphagia
– Stroke
– Bulbar palsy
– Pharyngeal disease (e.g., malignancy)
– Neuromuscular disorders (e.g., multiple sclerosis)
Additional Risk Factors:
– Tracheo-oesophageal fistula
– Ventilator-associated pneumonia
– Periodontal disease
– Gastro-oesophageal reflux
– Post-gastrectomy
– Tracheostomy
– Nasogastric tube feeding (now considered less risky)

– Occurs when foreign material enters the lungs, introducing bacteria and causing infection and inflammation
– The presence of foreign material can also cause chemical injury and damage to the lung tissue

– Community-acquired pneumonia
– Hospital-acquired pneumonia
– Lung abscess
– Pulmonary embolism
– Other respiratory infections
Other causes of respiratory distress:
– Other types of pneumonia
– Bronchiolitis
– Croup
– Epiglottitis
– Foreign body in respiratory tract
– Asthma
– Cardiovascular disease

– Prevalence: Not precisely defined but common overall, especially in certain demographics
– Higher prevalence in men, young children, and the elderly
– Frequent in hospital settings and linked to 10% of community-acquired pneumonia cases in elderly patients
– Often associated with multiple bacterial infections, including anaerobes

– Cough with sputum
– Fever, chills
– Shortness of breath
– Chest pain
– Confusion (older adults)
– Increased respiratory rate

– Headache
– Nausea
– Vomiting
– Anorexia
– Myalgia
– Weight loss

– Dyspnea (difficulty breathing)
– Pleuritic chest pain
– Purulent sputum

– Tachycardia (rapid heart rate)
– Tachypnea (rapid breathing)
– Decreased breath sounds
– Dullness to percussion over consolidation
– Pleural friction rub

– Hypoxia
– Septic shock (severe cases)

– Chest X-ray: Evaluates lung infiltrates or consolidation
– Sputum culture and analysis: Identifies the causative organism
– Blood tests: Assess white blood cell count and inflammatory markers
– Blood count: Neutrophil leukocytosis
– Electrolytes and renal function: Evaluates dehydration and electrolyte imbalance
– Blood culture
– Blood gases
– Culture of sputum: May reveal organisms from the pharynx in bacterial aspiration pneumonia
– Lung CT: Rarely required
– Bronchoscopy specimens: May guide antibiotic treatment choice

– Supportive care: Supplemental oxygen and adequate hydration
– Antibiotic therapy: Targeting the identified or suspected pathogens
– Chest physiotherapy: To assist with mucus clearance
– Management of underlying risk factors: Optimizing swallowing function, treating GERD
– Mechanical obstruction removal: Via bronchoscopy if necessary
– Tracheal suction: If caught early
– Intubation with positive pressure ventilation: If needed
– Antibacterial treatment: Based on patient characteristics, setting, severity, local pathogens, and resistance patterns
– Steroids: Role uncertain
– Supportive therapy: Fluid management, bronchodilators, physiotherapy
– Referral: To speech and language therapists

– Varies based on infection severity, underlying health conditions, timeliness of treatment, and presence of complications
– Complications are more likely in immunocompromised individuals or those with lung issues

– Keep head of the bed elevated at 30°: Reduces risk of aspiration
– Consider nasogastric feeding for at-risk individuals: Poor gag reflex, dysphagia

– Lung abscess formation
– Empyema (pus collection in the pleural cavity)
– Respiratory failure
– Sepsis
– Recurrent or chronic lung infections
– Untreated progression: Aspiration pneumonia may progress to lung abscess or bronchiectasis
– Acute respiratory distress