Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets (hemodynamic, neurologic, respiratory) and reassess frequently.
- Plan definitive source control or reperfusion when indicated; document follow‑up and patient education.
Algorithm
- Evaluate airway repeatedly; prepare for awake fiberoptic intubation or surgical airway if deterioration.
- Stop ACE inhibitor; avoid future ACEi exposure; consider ARB alternative with counseling.
- Supportive care, monitor progression; consider icatibant or C1-INH for severe oropharyngeal involvement.
- Observe until clear improvement; provide emergency plan and allergy referral.
Clinical Synopsis & Reasoning
Non-histaminergic swelling (often lips/tongue) typically within months to years of ACEi use. Prioritize airway management; epinephrine/antihistamines/steroids may have limited effect. Consider icatibant or C1-INH in severe cases; avoid ACEi permanently.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced or 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 |
|---|---|---|---|
| Airway assessment (repeat) | Safety | Stridor, voice change, drooling | Early ENT/anesthesia |
| Medication history | Etiology | ACE inhibitor exposure | Consider ARB cautiously if needed |
| C4 (if HAE suspected) | Differential | Low in C1-INH deficiency | Outpatient workup if recurrent |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Icatibant 30 mg SC (selected) | Bradykinin B2 antagonist | Hours | Severe bradykinin-mediated cases | Variable access/cost |
| C1-esterase inhibitor (IV) | C1-INH replacement | Hours | Alternate targeted therapy | Availability/cost |
| Epinephrine/antihistamines/steroids | Adrenergic/anti-inflammatory | Minutes-hours | Limited effect in ACEi angioedema | Still appropriate if mixed picture |
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
- WAO/EAACI recommendations on angioedema (2021) — Link