What is the initial approach to treating an acute respiratory infection in a SOAP (Subjective, Objective, Assessment, Plan) note?

SOAP Note for Acute Respiratory Infection

Subjective

Start by determining if this is remote or face-to-face contact, as this fundamentally changes your assessment approach. 1

Key History Elements to Document:

• Symptom onset and duration: Fever, cough, nasal symptoms, sore throat, myalgia, chills/sweats, malaise, fatigue, headache 2, 3
• Severity indicators: Breathlessness (new or increased), confusion, rate of symptom deterioration 1
• Red flags for sepsis: Think "could this be sepsis?" in every patient with suspected ARI 1
• Risk factors: Age >65 years, comorbidities (COPD, cardiovascular disease, diabetes), recent hospitalization, immunosuppression, recent antibiotic use 2, 3
• Social factors: Ability to manage at home, vomiting preventing oral intake, social isolation, dependency 3, 4
• Self-care attempted: Over-the-counter medications, hydration status 3

Remote Assessment Caveat:

If assessing remotely and the patient is potentially ill enough to require antimicrobials, arrange face-to-face assessment rather than prescribing remotely—this should be usual practice. 1

Objective

Vital Signs (Critical Decision Points):

Immediate hospital referral required if ANY of the following: 4

• Temperature <35°C or ≥40°C
• Heart rate ≥125 beats/min
• Respiratory rate ≥30 breaths/min
• Blood pressure <90/60 mmHg
• Oxygen saturation requiring assessment

Physical Examination:

• General appearance: Level of consciousness, confusion, drowsiness, cyanosis 4
• Respiratory examination:
  • Distinguish upper (above vocal cords, normal lung sounds) versus lower respiratory tract infection (abnormal lung sounds, respiratory distress) 2
  • Listen for signs of pneumonia: crackles, bronchial breathing, pleural effusion 4
• ENT examination for URTI: Pharyngeal erythema, tonsillar exudate (note: purulent nasal discharge alone does NOT indicate bacterial infection) 3

Point-of-Care Testing:

C-reactive protein (CRP) testing when available can inform antibiotic decisions if bacterial infection is suspected: 1

• CRP <20 mg/L: Do not routinely offer antibiotics
• CRP 20-100 mg/L: Consider back-up antibiotic prescription
• CRP >100 mg/L: Consider immediate antibiotics

Important limitation: CRP threshold of 20 mg/L has poor specificity (55%), meaning many without LRTI will have elevated CRP. 1

Assessment

Diagnostic Algorithm:

1. Upper Respiratory Tract Infection (URTI):

• Symptoms above vocal cords, normal lung examination 2
• Most are viral and self-limiting; <2% complicated by bacterial infection 3
• Discolored nasal discharge is inflammation, NOT bacterial infection 3

2. Acute Bronchitis:

• Cough with normal lung examination or diffuse wheezes 2
• Typically viral; antibiotics have no value (Grade C evidence) 2
• Consider antibiotics only if fever ≥38.5°C persisting >3 days 2

3. Community-Acquired Pneumonia (CAP):

• Clinical triad: fever, cough, respiratory distress 2
• Abnormal lung examination findings 2
• Use CRB65 score (1 point each for: Confusion, Respiratory rate ≥30, Blood pressure <90/60, age ≥65) 1, 2
  • Score 0: Consider home-based care
  • Score 1: Clinical judgment needed
  • Score ≥2: Consider hospital assessment 1

4. Acute Exacerbation of Chronic Bronchitis/COPD:

• Increased dyspnea, sputum volume, or sputum purulence in patient with known COPD 5
• Majority benefit from antibiotic treatment 4

5. Influenza:

• Fever with respiratory and systemic symptoms during influenza season 6
• Follow UK Health Security Agency seasonal advice 1

Plan

Treatment Algorithm Based on Diagnosis:

Upper Respiratory Tract Infection (URTI):

Do NOT prescribe antibiotics—they are ineffective for viral infections and contribute to resistance. 3

• Symptomatic treatment: Acetaminophen or ibuprofen for pain, fever, inflammation 3
• Supportive care: Adequate hydration and rest 3
• Adjunctive measures: Saline nasal irrigation, oral decongestants if no contraindications 3
• Safety netting: Advise return if symptoms persist >3 weeks, fever >4 days, worsening dyspnea, decreased oral intake, or decreased consciousness 3

Acute Bronchitis:

Antibiotics are NOT indicated in most cases. 2

• Symptomatic treatment as above 3
• Consider antibiotics only if high fever ≥38.5°C persisting >3 days 2
• If antibiotics needed: Amoxicillin 3g/day for 7-10 days 2

Community-Acquired Pneumonia (CAP):

Prompt antibiotic therapy is essential; delay increases mortality risk. 2, 5

For outpatients without risk factors: 2

• First-line: Amoxicillin 3g/day for 7-10 days
• Evaluate response within 48-72 hours; do not change therapy before 72 hours unless clinical worsening 2

For patients with risk factors (age >65, comorbidities, immunosuppression): 2

• Consider broader spectrum: amoxicillin-clavulanate, 2nd/3rd generation cephalosporin, or fluoroquinolone active against S. pneumoniae
• Consider atypical pathogen coverage if standard therapy fails 2

Hospital admission criteria (CRB65 ≥2 or clinical judgment): 1, 4

• Discuss care pathway options: hospital admission, virtual ward, community intervention team 1

Acute Exacerbation of Chronic Bronchitis/COPD:

• Antibiotics indicated for majority of patients 4
• First-line: Amoxicillin or tetracycline for 7-10 days 4
• Obtain sputum culture before starting antibiotics if hospitalization required 4

Influenza:

Antiviral therapy must be initiated within 36-48 hours of symptom onset for optimal effect. 2

• Neuraminidase inhibitors (oseltamivir, zanamivir): Effective for influenza A and B, reduce illness duration by ~2 days, prevent secondary complications 2
• Oseltamivir 75 mg twice daily for 5 days 6

Oxygen Therapy (if respiratory distress present):

Continuous oxygen indicated for: 2

• PaO2 <8 kPa
• Systolic blood pressure <100 mmHg
• Metabolic acidosis with bicarbonate <18 mmol/L
• Respiratory rate >30/min

Target: PaO2 >8 kPa or SaO2 >92% 2

Prevention:

• Annual influenza vaccination for high-risk patients (age ≥65, chronic cardiac/pulmonary disease, diabetes, institutionalized) 4
• Pneumococcal vaccination for at-risk adults 4

Common Pitfalls to Avoid:

• Prescribing antibiotics for viral URIs (ineffective, promotes resistance) 3
• Delaying antibiotics in suspected bacterial pneumonia (increases mortality) 2
• Remote antibiotic prescribing without face-to-face assessment when patient appears ill enough to need antimicrobials 1
• Assuming purulent discharge indicates bacterial infection (it indicates inflammation) 3
• Changing antibiotics before 72 hours unless clinical worsening 2
• Using sputum Gram stain alone to guide initial CAP therapy (limited reliability) 2
• Failing to recognize severity and need for hospitalization in high-risk patients 2

Follow-up:

• Reassess within 48-72 hours if antibiotics prescribed 2, 3
• Symptoms should begin improving within 48-72 hours of effective treatment for pneumonia 2
• If no improvement or worsening, consider treatment failure and reassess for complications or alternative diagnoses 2, 3