Pneumonia

Key Points

  • Pneumonia: acute infection causing inflammation of the alveoli → alveoli fill with fluid/purulent material → impaired gas exchange
  • CAP remains a major mortality burden (eighth leading cause of death in the United States; high global burden).
  • Highest risk: Adults >65 years, infants/young children, COPD, immunocompromise
  • Priority assessments: SpO2, respiratory rate, sputum characteristics, mental status changes
  • Diagnostic: Chest X-ray (consolidation) + CBC (elevated WBC) + sputum culture (guide antibiotic choice)
  • Target SpO2: >92% — oxygen therapy titrated to maintain this level
  • CURB-65 supports admission and ICU triage decisions in CAP.
  • VAP prevention: HOB elevated 30–45°, oral hygiene every 2–4 hours, daily sedation vacation

Pathophysiology

Pneumonia is caused by microorganism invasion of the alveoli → inflammatory response → alveolar filling with fluid and purulent exudate → impaired gas exchange → hypoxia.

Lobar pneumonia illustration comparing normal alveoli with inflamed fluid-filled alveolar spaces Illustration reference: OpenStax Medical-Surgical Nursing Ch.11.7.

Hospitalized pneumonia carries meaningful mortality risk, so early recognition and escalation are essential.

Common causative organisms:

  • Bacteria: Streptococcus pneumoniae (most common), Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, group A streptococci, aerobic gram-negative organisms (for example Klebsiella and Escherichia coli), Legionella, Mycoplasma pneumoniae, and Chlamydia species
  • Viruses: Influenza A/B, SARS-CoV-2 and other coronaviruses, rhinovirus, parainfluenza, adenovirus, RSV, human metapneumovirus, and human bocavirus
  • Fungi: Blastomyces, Histoplasma, Coccidioides, and selected opportunistic pathogens in immunocompromised hosts

Classification of Pneumonia

TypeDefinitionKey Considerations
CAP (Community-Acquired)Acquired outside healthcare settingsMost common; outpatient or hospitalized treatment
HAP (Hospital-Acquired)Onset ≥48 hours after hospital admissionOften caused by drug-resistant organisms
VAP (Ventilator-Associated)Occurring after intubation and mechanical ventilationHigh mortality risk; requires aggressive prevention
aspiration-pneumonia (Aspiration Pneumonia)Inhalation of food, vomit, saliva, or medicationsRisk: dysphagia (dysphagia), impaired gag reflex, oversedation, alcohol/drug use

Common HAP/VAP organisms include Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Enterobacter, and Acinetobacter.

Risk Factors and Severity Context

  • Older age increases hospitalization risk; adults over 65 are at markedly increased CAP admission risk.
  • Chronic lung disease, especially COPD, is a major risk factor for pneumonia-related hospitalization.
  • Immunocompromise increases severity risk, including fungal pneumonia susceptibility.
  • Aspiration-prone states (dysphagia, anesthesia, alcohol or drug effects, neurologic disease) raise pneumonia risk.
  • Heavy alcohol use, opioid exposure, and smoking increase pneumonia risk.
  • Socioeconomic and environmental exposure factors (poverty, crowded housing/shelters/prisons, inhalational toxin exposure) increase CAP risk and poor outcomes.

Clinical Manifestations

Body SystemSigns and Symptoms
RespiratoryCough (nonproductive or productive of purulent sputum), dyspnea, tachypnea, pleuritic chest pain, fine crackles on auscultation, ↓ SpO2
CardiovascularTachycardia
NeurologicalNew onset confusion or altered mental status (especially older adults)
GeneralFever, shaking chills (especially high fever), malaise, fatigue, weight loss
MusculoskeletalMuscle aches and joint pain (common with viral pneumonia)
IntegumentaryDiaphoresis, cyanosis (severe hypoxia)

Sputum in bacterial pneumonia is often purulent or blood-tinged. Viral-pattern sputum may be watery, though mixed mucus or pus can still be seen.

Altered Mental Status in Pneumonia

New onset confusion or altered mental status — especially in older adults — may be the first and only symptom of pneumonia. Always assess for respiratory infection when mental status changes acutely in elderly patients.

Diagnostic Tests

Initial Assessment:

TestFinding in Pneumonia
Chest X-rayConsolidation — areas of opacification (fluid/exudate in alveoli)
CBCElevated WBC (leukocytosis) → indicates infection
Sputum cultureIdentifies causative organism → guides antibiotic selection
Pulse oximetry↓ SpO2 — severity indicator
CURB-65 scoreSupports outpatient vs. admission vs. ICU triage

Additional Testing for Hospitalized/Severe Cases:

  • ABG: Assess PaO2, PaCO2, pH — determines severity of hypoxemia/hypercapnia
  • Blood cultures: Determine if bacteremia (systemic spread) has occurred
  • CT scan: Detailed lung imaging when diagnosis uncertain
  • Bronchoscopy: Direct visualization; sample collection when cause unclear
  • Pleural fluid culture (thoracentesis): If pleural effusion present
  • Urinary antigen testing: Useful in selected pathogens such as suspected Legionella
  • CRP/procalcitonin: Supports bacterial-versus-viral pattern differentiation
  • Lactate: Helps risk-stratify possible septic pneumonia

Medical Management

Medication Therapy

CategoryUse
AntibioticsBacterial pneumonia — choice based on type (CAP vs. HAP/VAP) and culture results; may adjust after sensitivity results
AntiviralsViral pneumonia (e.g., oseltamivir for influenza); antibiotics are not effective for viral-only causes
AntifungalsFungal pneumonia (e.g., fluconazole, trimethoprim-sulfamethoxazole for PCP)
BronchodilatorsAlbuterol — relieves bronchoconstriction, especially in COPD/asthma patients
CorticosteroidsReduce severe airway inflammation
AntipyreticsAcetaminophen or ibuprofen for fever and discomfort

Respiratory Support

  • Supplemental oxygen: Titrate to maintain SpO2 >92%
  • Incentive spirometry: Prevents atelectasis — instruct to use every 1–2 hours while awake
  • Chest physiotherapy: Postural drainage and percussion — assists in clearing secretions
  • BiPAP/CPAP: Non-invasive positive pressure ventilation for moderate-severe respiratory failure
  • Mechanical ventilation: Severe cases requiring intubation
  • Pleural procedures for pleural effusion: Thoracentesis and, when indicated, chest tube insertion to support lung re-expansion

Fluid Management

  • Encourage oral fluids to thin secretions, with a practical target of about 2 liters/day unless fluid restriction is ordered
  • IV fluids for high fever, poor oral intake, or dysphagia

Nursing Interventions

Priority Nursing Actions

Airway Clearance:

  • Encourage coughing and deep breathing exercises hourly while awake
  • Suction if patient cannot clear secretions independently
  • Administer mucolytics/expectorants as ordered
  • Positioning — upright (HOB 30–45°) to maximize lung expansion
  • If aspiration risk is present, maintain NPO until a trained provider or SLP completes an evidence-based swallow screen.

Oxygenation:

  • Monitor SpO2 continuously; maintain >92%
  • Apply oxygen per orders; titrate to SpO2 target
  • Assess respiratory rate, depth, and lung sounds every 4 hours
  • Monitor ABG results as ordered

Infection Control:

VAP Prevention Bundle (for ventilated patients):

  • HOB elevation 30–45°
  • Oral hygiene every 2–4 hours with antiseptic
  • Daily sedation vacation to assess readiness for extubation
  • Deep vein thrombosis (DVT) prophylaxis
  • Peptic ulcer disease prophylaxis

Patient Education

  • Complete full course of antibiotics — even when feeling better
  • Vaccination: Keep influenza vaccination current and follow pneumococcal vaccine recommendations, especially for at-risk adults and all adults age 65 or older
  • Smoking cessation — smoking is major risk factor
  • Oral hygiene to reduce aspiration risk
  • Return precautions: worsening dyspnea, coughing up blood, fever >101°F (38.3°C)

Severity-Guided Antimicrobial Strategy

  • CAP with CURB-65 0-1: Outpatient-leaning therapy; common options include macrolide or doxycycline when major comorbidity burden is low, with broader regimens when significant comorbid risk is present.
  • CAP with CURB-65 2-3: Inpatient-level therapy is commonly recommended, often using broader dual-class coverage.
  • CAP with CURB-65 4-5: ICU-level management with broad coverage is typically required.
  • HAP/VAP: Broad-spectrum regimens are commonly used initially, then narrowed once microbiology and resistance data are available.

Evaluation and Care Plan Revision

  • Reevaluate outcomes after interventions, new lab/diagnostic results, and interprofessional care-plan discussions
  • Determine whether expected outcomes are met, partially met, or not met within the planned timeframe
  • Revise the nursing care plan when outcomes are partially met or not met

CURB-65 Quick Triage

  • Confusion: 1 point
  • Uremia (BUN >20 mg/dL): 1 point
  • Respiratory rate >=30/min: 1 point
  • Blood pressure (SBP <90 mmHg or DBP <60 mmHg): 1 point
  • Age >=65 years: 1 point
  • Score 0-1: often outpatient management
  • Score 2-3: hospital admission generally recommended
  • Score 4-5: ICU-level care typically recommended

Self-Check

  1. An 80-year-old patient with pneumonia is oriented x1 (knows name only), febrile at 101.8°F, and has fine crackles bilaterally. SpO2 is 89% on room air. What is the priority nursing intervention, and what SpO2 target should the nurse maintain?
  2. A nurse is about to administer the first dose of antibiotics for a patient diagnosed with community-acquired pneumonia. What should be done before administering the antibiotic, and why?
  3. A ventilated patient in the ICU develops a new fever, purulent sputum, and chest X-ray showing new infiltrate 3 days after intubation. What type of pneumonia is suspected, and what prevention measures should have been implemented?