Key Points
- Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
- Use system-specific risk tools to guide testing and disposition.
- Order high-yield tests first; escalate imaging when indicated.
- Start evidence-based initial therapy and reassess frequently.
Algorithm
- Primary survey and vitals; IV access and monitors.
- Focused history/physical; identify red flags and likely etiologies.
- Order system-appropriate labs and imaging (see Investigations).
- Initiate guideline-based empiric therapy (see Pharmacology).
- Reassess response; arrange consultation and definitive management.
Clinical Synopsis & Reasoning
For Influenza In Adults Testing Antivirals, frame the differential by acuity and pathophysiology, then align diagnostics to the leading hypotheses. Prioritize stabilization while obtaining high‑yield studies such as CBC (Inflammation/infection), Lactate (Hypoperfusion), Blood cultures (Pathogen ID). Incorporate bedside imaging and targeted labs to define severity and identify complications; synthesize results with clinical trajectory to refine the working diagnosis and disposition needs.
Treatment Strategy & Disposition
Initiate disease‑directed therapy alongside supportive care, titrating to objective response. Pharmacologic options commonly include Broad-spectrum antibiotics. Use validated frameworks (e.g., Antivirals (Adults — Examples)) to guide escalation and site of care. Address precipitating factors, de‑escalate empiric therapies with data, and arrange follow‑up for monitoring and risk‑factor modification; admit patients with instability, high risk of deterioration, or needs for close monitoring.
Management Notes
Begin treatment empirically in hospitalized or severe cases without waiting for test results. Watch for secondary bacterial pneumonia.
Epidemiology / Risk Factors
- Immunosuppression, devices; recent hospitalization
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| CBC | Inflammation/infection | Leukocytosis/leukopenia | |
| Lactate | Hypoperfusion | Elevated | Trend |
| Blood cultures | Pathogen ID | Positive/negative | Before antibiotics if feasible |
Antivirals (Adults — Examples)
| Drug | Dose | Notes |
|---|---|---|
| Oseltamivir | 75 mg BID ×5 days | Renal dose adjust |
| Zanamivir | Inhaled 10 mg BID ×5 days | Avoid in airway disease |
| Peramivir | 600 mg IV once | Hospitalized if unable PO |
| Baloxavir | Single weight‑based dose | Avoid in pregnancy? check labels |
| Prophylaxis | Oseltamivir daily ×7–10 days | For high‑risk exposures |
Pharmacology
| Medication | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Oseltamivir | Neuraminidase inhibitor | Days | High-risk or severe cases | Nausea/vomiting |
Prognosis / Complications
- Depends on host and source control; sepsis/organ failure risk
Patient Education / Counseling
- Explain red flags and when to seek emergent care.
- Reinforce medication adherence and follow-up plan.
References
- CDC/IDSA Influenza Guidance — Link