How to document respiratory system findings in a case of Lower Respiratory Tract Infection (LRTI)?

Documentation of Respiratory System Findings in Lower Respiratory Tract Infection

Document respiratory system findings systematically by recording specific clinical parameters that determine severity, guide management decisions, and predict bacterial etiology requiring antibiotic therapy.

Essential Clinical Parameters to Document

Vital Signs and Severity Markers

• Temperature: Record exact value, noting if <35°C or ≥40°C, as these extremes indicate immediate severity requiring hospital referral 1
• Respiratory rate: Document breaths per minute, with ≥30 breaths/min indicating severe disease and hospital admission 1
• Heart rate: Record beats per minute, with ≥125 beats/min suggesting immediate severity 1
• Blood pressure: Document systolic/diastolic values, as <90/60 mmHg indicates hemodynamic compromise requiring hospitalization 1
• Oxygen saturation: Record SpO2 on room air, with PaO2 <60 mmHg or need for supplemental oxygen indicating severity 1

Respiratory Examination Findings

• Focal chest signs: Document presence or absence of new focal auscultatory abnormalities, as these increase pneumonia probability from 5-10% to 39% and are key diagnostic criteria 1
• Cough characteristics: Record whether productive or dry, duration (fever >4 days suggests pneumonia), and presence of purulent sputum 1, 2
• Dyspnea/tachypnea: Document presence and severity, as these are cardinal features distinguishing pneumonia from acute bronchitis 1
• Abnormal breath sounds: Specify crackles, wheezes, bronchial breathing, percussion dullness, or pleural rub if present 1
• Cyanosis: Document if present, as this indicates severe hypoxemia requiring immediate intervention 1

Mental Status and General Appearance

• Level of consciousness: Record any confusion, drowsiness, or altered mental status, as these indicate immediate severity 1
• Overall clinical impression: Document whether patient appears "unwell," as this assessment increases pneumonia likelihood fivefold 2

Risk Stratification Documentation

Patient Risk Factors

Document presence of:

• Age >65 years: Increases risk of Streptococcus pneumoniae and severity 1
• Comorbidities: Specifically note COPD, cardiovascular disease, diabetes mellitus, chronic liver/renal failure, neurological diseases 1
• Recent hospitalization: Within previous year (resistant S. pneumoniae) or 2-4 weeks (gram-negative bacilli) 1
• Recent antibiotic use: Increases risk of resistant organisms 1
• Institutionalization: Associated with different pathogen spectrum 1
• Aspiration risk: Document swallowing difficulties 1

Laboratory and Radiographic Findings

Point-of-Care Testing

• C-reactive protein (CRP): Document exact value; CRP >50 mg/L has 93.8% sensitivity for bacterial LRTI requiring antibiotics, while >100 mg/L has 91.9% specificity 3. Even CRP ≥11 mg/L is associated with pneumonia diagnosis 2
• White blood cell count: Record absolute value; <4,000 cells/mL (leukopenia) or >20,000 cells/mL (severe leukocytosis) indicates hospital management 1. WBC >16 x 10^9/L has 94.2% specificity but only 37.5% sensitivity 3
• Procalcitonin (PCT): If available, PCT >0.1 ng/mL has 93.8% sensitivity, while >0.25 ng/mL has 97.7% specificity for bacterial LRTI 3

Chest Radiograph

• Infiltrates: Document presence, location, and extent (multilobar involvement indicates severity) 1
• Complications: Note pleural effusion, cavitation, or other abnormalities requiring hospital management 1
• Radiograph confirmation: Essential when pneumonia is suspected clinically, as infiltrates have 96.9% sensitivity for bacterial LRTI requiring antibiotics 1, 3

Clinical Syndrome Classification

Document the specific LRTI subtype:

• Community-acquired pneumonia (CAP): Acute cough with at least one of new focal chest signs, fever >4 days, or dyspnea/tachypnea 1
• Acute bronchitis: Acute illness with cough in patient without chronic lung disease, no focal signs 1
• COPD exacerbation: Worsening baseline dyspnea, cough, and/or sputum beyond day-to-day variability 1
• Bronchiectasis exacerbation: Similar worsening in patient with known bronchiectasis 1

Predictors of Bacterial Etiology

When documenting findings, note independent predictors of bacterial (vs. viral) infection:

• Fever: Odds ratio 8.0 for bacterial infection 4
• Headache: Odds ratio 4.3 4
• Cervical lymphadenopathy: Odds ratio 8.7 4
• Absence of rhinitis: Odds ratio 0.3 (protective against bacterial) 4
• Absence of diarrhea: Odds ratio 0.3 (protective against bacterial) 4

Common Documentation Pitfalls to Avoid

• Do not rely on sputum color alone: Purulent sputum is insensitive and nonspecific for bacterial LRTI 3
• Do not assume discolored nasal discharge indicates bacterial infection: This alone does not warrant antibiotics 5
• Do not document "bronchitis" without specifying acute vs. chronic: This term means different things and should be avoided in favor of symptom description 6
• Do not omit chest X-ray documentation when pneumonia is suspected: Clinical diagnosis alone is insufficient 1

Hospital Referral Documentation

Clearly document if any hospital referral criteria are met:

• Immediate severity signs: Temperature extremes, tachycardia, tachypnea, hypotension, cyanosis, altered mental status 1
• Biological criteria: Leukopenia, severe leukocytosis, anemia (Hgb <9 g/dL), renal impairment, hypoxemia, acidosis 1
• Radiological criteria: Multilobar involvement, pleural effusion, cavitation 1
• Social factors: Inability to manage at home, poor compliance likelihood, social isolation 1