What is the initial management for emergency cases of flu-like symptoms?

Emergency Management of Flu-Like Symptoms

The initial management for emergency cases of flu-like symptoms should include oxygen therapy for hypoxic patients, antiviral treatment with oseltamivir 75 mg twice daily for 5 days if within 48 hours of symptom onset, and appropriate monitoring of vital signs using an Early Warning Score system. 1

Initial Assessment and Monitoring

• Monitor and document the following vital signs at least twice daily (more frequently in severe cases):

  • Temperature
  • Respiratory rate
  • Pulse
  • Blood pressure
  • Mental status
  • Oxygen saturation
  • Inspired oxygen concentration 2, 1

• Use an Early Warning Score system for efficient monitoring 1

• Look for signs of clinical instability:

  • Temperature >37.8°C
  • Heart rate >100/min
  • Respiratory rate >24/min
  • Systolic blood pressure <90 mmHg
  • Oxygen saturation <90%
  • Inability to maintain oral intake
  • Abnormal mental status 1

Oxygen Therapy and Supportive Care

• Provide oxygen therapy to hypoxic patients with monitoring of oxygen saturations
• Aim to maintain PaO2 ≥8 kPa and SaO2 ≥92% 2
• For patients with pre-existing COPD and ventilatory failure, guide oxygen therapy with repeated arterial blood gas measurements 2
• Consider non-invasive ventilation (NIV) for patients with respiratory failure 2
• Assess for cardiac complications, volume depletion, and need for intravenous fluids 2, 1
• Provide nutritional support in severe or prolonged illness 2, 1
• Ensure adequate fluid intake and rest until fever resolves 1

Antiviral Therapy

• Initiate oseltamivir treatment if the patient meets all criteria:

  • Acute influenza-like illness
  • Fever >38°C
  • Symptomatic for two days or less 2, 1

• Dosage:

  • Adults: Oseltamivir 75 mg twice daily for 5 days
  • Reduce dose to 75 mg once daily if creatinine clearance <30 ml/min 2, 1

• Special considerations:

  • Immunocompromised or elderly patients may benefit from antiviral treatment despite lack of documented fever 2, 1
  • Severely ill hospitalized patients may benefit from antiviral treatment started >48 hours from disease onset, although evidence is limited 2, 3
  • Earlier treatment initiation (within 24 hours) provides greater benefits in reducing illness duration 4, 5

Symptomatic Treatment

• Acetaminophen: 650-1000 mg every 4-6 hours (maximum 4000 mg/day) for fever and pain relief 1
• Dextromethorphan: 10-30 mg every 4-8 hours (maximum 120 mg/day) for non-productive cough 1
• Guaifenesin: 200-400 mg every 4 hours (maximum 2400 mg/day) for productive cough 1
• Pseudoephedrine: 60 mg every 4-6 hours (maximum 240 mg/day) for nasal congestion (use with caution in patients with hypertension, cardiovascular disease, or glaucoma) 1

Antibiotic Therapy

• Antibiotics are not routinely required for previously well adults with acute bronchitis complicating influenza 2, 1

• Consider antibiotics for:

  • Patients with worsening symptoms (recrudescent fever or increasing dyspnea)
  • High-risk patients with lower respiratory features 2, 1

• When antibiotics are indicated:

  • First-line: Co-amoxiclav or tetracycline (doxycycline)
  • Alternative for penicillin-intolerant patients: Macrolides (clarithromycin/erythromycin) or respiratory fluoroquinolone 1
  • Administer within 4 hours of admission for severe cases 1

Diagnostic Testing

• For non-severe cases: No routine testing required
• For severe cases (CURB-65 Score 3-5 or bilateral CXR changes):
  • Blood culture (preferably before antibiotic treatment)
  • Pneumococcal urine antigen
  • Sputum Gram stain, culture, and antimicrobial susceptibility tests
  • Paired serological examination for influenza/other agents
  • Tracheal or endotracheal aspirate samples if available 2

Discharge Criteria and Follow-up

• Review patients 24 hours prior to discharge

• Patients should not be discharged if they have two or more of the following:

  • Temperature >37.8°C
  • Heart rate >100/min
  • Respiratory rate >24/min
  • Systolic blood pressure <90 mmHg
  • Oxygen saturation <90%
  • Inability to maintain oral intake
  • Abnormal mental status 2, 1

• Arrange follow-up for patients who:

  • Suffered significant complications
  • Had significant worsening of underlying disease 2, 1

• Provide information about illness, medications, and follow-up arrangements at discharge 2, 1

Special Considerations for High-Risk Patients

• More vigilant monitoring for:

  • Elderly (≥65 years)
  • Children <2 years
  • Patients with chronic medical conditions
  • Immunocompromised individuals
  • Pregnant women 1

• Consider closer monitoring and potential hospital admission for these high-risk groups 1