What is the treatment for unilateral laryngeal and parotid edema?

Treatment of Unilateral Laryngeal and Parotid Edema

The treatment approach depends critically on the underlying etiology: if this represents hereditary angioedema (HAE), use C1-INH replacement therapy, icatibant, or ecallantide as first-line treatment; if HAE-specific therapies are unavailable, fresh frozen plasma (10-20 ml/kg) can be lifesaving for laryngeal involvement; if this represents inflammatory edema from trauma or other causes, initiate corticosteroids immediately and maintain airway patency as the primary goal. 1

Immediate Airway Assessment and Management

• All patients with laryngeal edema must be observed in a facility capable of performing intubation or tracheostomy, as laryngeal attacks can progress to complete airway obstruction 1
• Closely monitor for signs of impending airway closure: change in voice, loss of ability to swallow, and difficulty breathing 1
• Consider early intubation or tracheotomy in upper airway angioedema, particularly when first-line treatments are unavailable 1
• Keep the patient upright and administer high-flow humidified oxygen 1
• Maintain NPO status as laryngeal competence may be impaired despite full consciousness 1

Treatment Based on Etiology

If Hereditary Angioedema (HAE) is Suspected or Confirmed

First-line therapies (all equally effective): 1

• Plasma-derived C1-INH (1000-2000 U or 20 U/kg)
• Icatibant (bradykinin B2 receptor antagonist) 30 mg subcutaneously; may repeat at 6-hour intervals (maximum 3 doses in 24 hours) 2
• Ecallantide (plasma kallikrein inhibitor)

Critical points about HAE treatment:

• Standard treatments for allergic angioedema (epinephrine, corticosteroids, antihistamines) do NOT work for HAE 1
• Epinephrine is not considered helpful for angioedema caused by C1 inhibitor deficiency 1
• Treatment should be administered as early as possible in an attack 1

If first-line HAE therapies are unavailable:

• Fresh frozen plasma (FFP) 10-20 ml/kg (approximately 400-560 ml in adults) is effective but slower-acting 1
• FFP contains approximately 1 unit/ml of C1-INH and has been successful in treating laryngeal attacks 1
• Response time with FFP: first improvement at 90 minutes to 12 hours, with resolution between 2-12 hours 1
• Caution: FFP carries risks of transfusion reactions (including anaphylaxis in rare cases), pathogen transmission, and volume overload 1
• Theoretical risk of worsening symptoms exists but is rarely reported 1

If Inflammatory/Traumatic Laryngeal Edema

Corticosteroid therapy (for inflammatory edema from intubation, surgery, or trauma):

• Methylprednisolone 20-40 mg IV every 4-6 hours, initiated at least 12-24 hours before planned extubation in high-risk patients 2, 3, 4
• Alternatively, dexamethasone 5-8 mg IV every 6 hours for 4 doses 5, 6
• Single-dose steroids given immediately before extubation are ineffective 1
• Steroids should be started as soon as possible and continued for at least 12 hours 1
• Steroids are effective for inflammatory airway edema but have no effect on mechanical edema secondary to venous obstruction 1

Adjunctive therapies for inflammatory edema:

• Nebulized epinephrine (1 mg) may reduce airway edema if upper respiratory obstruction or stridor develops 1
• The effect is quick (30 minutes) but transient (2 hours), requiring continued monitoring 1
• IV diphenhydramine 50 mg plus ranitidine 50 mg IV or famotidine 20 mg IV 2

If ACE Inhibitor-Associated Angioedema

• Discontinue the ACE inhibitor immediately 2
• Consider icatibant 30 mg subcutaneously (selective bradykinin B2 receptor antagonist) 2
• Plasma-derived C1 esterase inhibitor (20 IU/kg) may be considered 2
• Standard antihistamines and corticosteroids are generally ineffective for bradykinin-mediated angioedema 1

Monitoring and Supportive Care

• Aggressive hydration for third-space fluid sequestration 1
• Narcotic medications for pain control if needed, but avoid potent narcotics like fentanyl patches or oxycodone out-of-hospital 1
• Antiemetics for nausea and vomiting 1
• End-tidal CO2 monitoring is desirable 1

Common Pitfalls and Caveats

• Do not assume all angioedema responds to epinephrine, antihistamines, and steroids - HAE and ACE inhibitor-induced angioedema are bradykinin-mediated and require different treatment 1
• Do not delay definitive airway management in progressive laryngeal edema - intubation becomes increasingly difficult as swelling progresses 1
• Large volume fluid resuscitation can worsen airway swelling 2
• FFP can theoretically worsen HAE attacks (contains contact proteins), though this is rarely reported 1
• The unilateral presentation is unusual and should prompt consideration of other diagnoses (tumor, abscess, trauma) if the clinical picture doesn't fit angioedema 7