What is the management of angioedema?

Management of Angioedema

The management of angioedema requires immediate identification of the type (histamine-mediated vs. bradykinin-mediated) and prompt initiation of appropriate treatment based on this classification, with airway assessment being the first priority in all cases. 1

Initial Assessment and Airway Management

• Airway evaluation is the first priority in all angioedema cases
• Upper airway edema should be treated as a medical emergency regardless of suspected cause 1
• Early elective intubation should be considered if signs of airway compromise develop 1
• High-risk features requiring close airway monitoring:
  • Edema involving larynx, palate, floor of mouth, or oropharynx
  • Rapid progression (within 30 minutes)
  • Oxygen saturation below 92% 1
• Be prepared for emergency tracheotomy if intubation fails in severe cases 1
• All patients with oropharyngeal or laryngeal angioedema should be observed in a facility capable of emergency airway management 1

Treatment Based on Angioedema Type

1. Histamine-Mediated Angioedema (with urticaria/hives)

• First-line treatment:
  • H1 antihistamines (e.g., diphenhydramine 50 mg IV) 1
  • Corticosteroids (e.g., methylprednisolone 125 mg IV) 1
  • Epinephrine for severe cases or laryngeal involvement 2

2. Bradykinin-Mediated Angioedema

A. Hereditary Angioedema (HAE)

• First-line treatments for acute attacks:
  • Icatibant 30 mg subcutaneously in abdominal area (may repeat at 6-hour intervals, not exceeding 3 injections in 24 hours) 1, 3
  • Plasma-derived C1 esterase inhibitor (20 IU/kg) 1
  • Patients may self-administer upon recognition of an HAE attack 3

B. ACE Inhibitor-Induced Angioedema

• Immediate discontinuation of the ACE inhibitor 1
• Icatibant may be effective 4
• Antihistamines, corticosteroids, and epinephrine are generally ineffective 4

C. Acquired C1 Inhibitor Deficiency

• Plasma-derived C1 esterase inhibitor 1
• Fresh frozen plasma (10-15 ml/kg) can be considered as an alternative therapy in resource-limited settings 1

Special Considerations

Risk Factors to Assess

• African Americans are at higher risk for ACE inhibitor-induced angioedema 1
• People over 65, women, and those with a history of smoking are also at increased risk 1

Long-term Prophylaxis for HAE

• Options include:
  • Plasma-derived C1INH replacement
  • Lanadelumab
  • Attenuated androgens (contraindicated in pregnancy)
  • Antifibrinolytic agents (e.g., tranexamic acid 15-25 mg/kg 2-3 times daily) 1

Medication Precautions

• ACE inhibitors should be avoided in patients with any form of bradykinin-mediated angioedema 1
• Estrogen-containing contraceptives should be avoided in women with HAE 1
• In pregnancy, androgens are contraindicated; plasma-derived C1INH is preferred 1

Patient Education and Follow-up

• Provide emergency action plans and medical alert identification 1
• Consider prescribing self-injectable epinephrine for patients with histamine-mediated angioedema, particularly those with:
  • Younger age
  • Throat tightness/fullness 5
  • History of respiratory symptoms

Common Pitfalls to Avoid

1. Misclassification of angioedema type: Bradykinin-mediated angioedema will not respond to antihistamines, corticosteroids, or epinephrine 4

2. Delayed airway intervention: Angioedema can progress rapidly; early airway management is critical 6

3. Continuing ACE inhibitors: After an episode of ACE inhibitor-induced angioedema, lifetime discontinuation of all renin-angiotensin inhibitors may be warranted 1

4. Inadequate monitoring: Even after apparent improvement, patients with head and neck angioedema should be observed for potential airway compromise 1

5. Failure to provide long-term management plan: Patients with recurrent angioedema need appropriate prophylaxis and emergency medications 1