Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Administer SABA ± ipratropium and oxygen; start systemic steroids early.
- Reassess; give IV magnesium if severe; consider epinephrine for refractory bronchospasm.
- Decide disposition based on response and peak flow; optimize controller therapy and action plan at discharge.
Clinical Synopsis & Reasoning
Treat acute asthma with repeated inhaled short-acting beta-agonists (± ipratropium for severe), early systemic corticosteroids, and adjunct IV magnesium for severe exacerbations; provide oxygen to maintain SpO₂ 93–95%. Consider epinephrine and noninvasive ventilation/intubation if impending failure.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| Peak flow/FEV1 and pulse oximetry | Severity | <50% predicted = severe | Track response |
| Chest X-ray (selected) | Differential | Rule out pneumonia/pneumothorax | — |
| ABG if deteriorating | Ventilation | Rising PaCO₂ indicates fatigue | — |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Silent chest/AMS/normal-high PaCO2 | Impending failure | ICU; consider intubation |
| Poor response to initial therapy | Refractory | IV magnesium; epinephrine |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Albuterol (back-to-back or continuous) ± Ipratropium | Bronchodilators | Minutes | First-line | — |
| Prednisone 40–60 mg PO (or IV methylpred) | Steroid | Hours | Reduce inflammation/relapse | 5–10 days typical |
| Magnesium sulfate 2 g IV over 20 min (severe) | Bronchodilator adjunct | Minutes | Improves airflow | Safe in most adults |
| Epinephrine IM (severe refractory or anaphylaxis) | Adrenergic | Minutes | Rescue | Monitor closely |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- GINA adult asthma strategy documents — Link