Treatment:
Control airway early if tongue swelling:
-
Consider flex/fiber optic visualization
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Be prepared for surgical airway
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Consider ketamine for awake intubation, fiber optic nasopharyngeal intubation
- LMA is insufficient
If cause unknown, treat as histamine related with epinephrine, H1 & H2 blockers, and corticosteroids.
Meds:
- Epinephrine- IM preferred due to longer action
-
0.01 mg/kg of 1:1000, max 0.5 mg IM
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Do not withhold due to hx heart disease
-
-
Steroids
-
60-120 mg Methylpredinisolone IV
-
Dexamethasone is a good alternative
-
-
FFP may be of use in ACE inhibitor related angioedema
-
FFP has been (rarely) reported to worsen herditary angioedema
-
-
Novel therapies (icatibant, ecallantide, C1-inh concentrate) are effective in HAE.
-
May be effective in ACE inhibitor related cases, but data limited.
-
Classification:
Anaphylaxis –
- Common triggers include foods, insect stings, and drugs; IgE mediated
- Symptoms include wheezing, chest tightness, and hypotension
Histaminergic angioedema without anaphylaxis (allergic and idiopathic) –
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Common triggers include foods, insect stings, and drugs;
-
Presents as rash;
- Mast cell degranulation or IgE mediated
Non-histaminergic (bradykinin mediated):
-
No urticaria
- More likely to have abdominal symptoms
- Frequently involves upper airway
- Does not responded to corticosteroids or antihistamines
-
Poorly responsive to epinephrine
-
Lasts 2-5 days
- 3 subtypes- Hereditary Angioedema, ACE-induced, and Acquired C1-Inh def.
Non-histaminergic Subtypes:
1) Drug related:
-
Angiotensin receptor blockers and renin antagonists also shown to cause angioedema through and unknown mechanism.
-
Up to 30% Ace-inhibitor induced, of these18% admission rate
-
0.1% to 0.7% on ACE get angioedema
-
Highest incidence during first 30 days of therapy but can occur anytime
-
Most common among African Americans
- Cyclooxygenase inhibitors lead to increased leukotriene mediators seen in NSAID reactions
2) Hereditary Angioedema:
-
Two types caused by abnormal C1-INH gene function resulting in increased production of bradykinin.
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Type 1:
- Low levels of C1-Inhibitor protein production
-
Rare, 1:50,000
-
Begins in childhood and may worsen in puberty
-
50% with recurring symptoms or abdominal pain by age 10
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Common prodrome symptom is erythema marginatum (not urticaria)
-
Type 2:
- More rare than type 1
-
Usually presents older, >40 yo
-
More common in women
-
More involvement of face and tongue
-
Estrogen containing products increase attacks
-
Respond to same meds as type 1, presumed to be bradykinin related
-
High C1-inh levels but dysfunctional
3) Acquired C1-Inhibitor deficiency:
-
Protein is consumed due to underlying lymphoproliferative disorder or antibody in 15% of cases
-
Other malignancies can be related
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age >40
Labs:
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C4 levels are low in HAE during an attack.
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normal C4 in a patient not on C1-acement, during an attack, excludes HAE.
-
if C4 is low, follow up testing includes C1-Inh level and function
-
-
Tryptase levels are high in mast cell mediated disorders
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normal in HAE
-
-
Labs are not helpful for ED treatment, but can be helpful for follow up care
Souce:
Moellman JJ, Bernstein JA, Lindsell C, et al. A consensus parameter for the evaluation and management of angioedema in the emergency department. Acad Emerg Med. 2014;21(4):469-84. PubMed
ABEM LLSA 2017