HWN Suggests

Swelling out of the Blue - Angioedema in the ED

The following can help differentiate ACEI angioedema from histamine-mediated allergic angioedema (although it will have more features in common with other forms of bradykinin-induced angioedema).

Starts with focal swelling (isolated swelling of tongue or lips, often asymmetric) Evolves over hours (slower progression than histamine-mediated angioedema). Absence of urticaria, itching, and other skin changes. Won’t respond in the classic way to antihistamines, steroids, or epinephrine. HAE specifically is more likely to involve swelling of the hands & feet and have been precipitated by stress...

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 Angioedema

Broadly speaking, we have the mast-cell / histamine-mediated vs bradykinin-mediated vs we-have-no-idea idiopathic mediated. Let’s focus on the more confusing treatments for bradykinin-mediated angioedema.

 Angioedema Basics

TXA inhibits plasminogen→ decreased production of bradykinin.

 Evaluation and Management of Angioedema in the Emergency Department

Patients with angioedema involving the tongue or larynx require consideration of definitive airway management. Angioedema can progress rapidly within hours, and airway obstruction occurs in up to 15% of patients with angioedema

 Initial Evaluation and Management of Patients Presenting with Acute Urticaria or Angioedema

Disposition of the patient with angioedema can be challenging for the emergency physician. As discussed, any patient with laryngeal edema by NPL should be admitted to the ICU for airway monitoring. In addition, ICU admission is also indicated for non-intubated patients with tongue edema or edema of the floor of the mouth.

 Treatment of Severe ACE Inhibitor Angioedema: Current and Future Therapies

For many years, corticosteroids, antihistamines, and epinephrine have been used to treat severe angioedema related to therapy with angiotensin-converting enzyme inhibitors (ACEIs). However, no clear evidence exists to support these therapies in patients who present with ACEI-induced angioedema.

Articles of Interest

Angioedema Evaluation and Management

You can think of angioedema in several different ways: bradykinin- or histamine-mediated, or hereditary (bradykinin) or acquired (bradykinin or histamine) (Table 1) (1-4,7,8,14). The underlying cause can impact the presentation and management in angioedema. Bradykinin-mediated forms are usually longer-lasting, more severe, and tend to affect the upper airway.

Angioedema in the Emergency Department: An Evidence-Based Update

When a patient presents to the ED with complaints of nonpitting edema, difficult breathing, and/or abdominal pain, angioedema may be at the top of your differential, but determining which of the 3 types of angioedema is presenting will be key to proper management.

Firazyr of Limited Help with Angioedema Caused by ACE Inhibitors

Firazyr (icatibant acetate) does not appear to be superior to placebo or symptomatic therapies in treating attacks of angioedema (swelling) caused by angiotensin-converting enzyme (ACE) inhibitors, a pooled analysis of three clinical studies shows.

How Not to Be Misled by Disorders Mimicking Angioedema: A Review of Pseudoangioedema

The majority of patients with angioedema describe a tingling, slightly numb or even burning sensation of the affected site, while itching is not a typical symptom.

Idiopathic Angioedema: Current Challenges

Mast-cell induced AE (MC‐AE) is the most frequent form, seen in 96% of consultations.1 MC‐AE can last from only a few hours up to several days and is often associated with hives, concomitant with or at some distance in time from the AE episode. So, searching for episodes of hives in the patient’s medical history is the first step in this challenging diagnosis.

Novelties in the Diagnosis and Treatment of Angioedema

Angioedema is defined as local, noninflammatory, self-limiting edema that is circumscribed owing to increased leakage of plasma from the capillaries located in the deep layers of the skin and the mucosae. Two mediators, histamine and bradykinin, account for most cases of angioedema. Angioedema can occur with wheals as a manifestation of urticaria, and this form is frequently allergic. In the present review, we discuss nonallergic angioedema without wheals, which can be divided into 3 acquired and 4 hereditary forms.

Urticaria & Angioedema

Differential diagnosis: Important to distinguish from other rashes that can mimic urticaria. Erythema multiforme, targetoid lesions. Papular urticaria: insect bite-induced hypersensitivity, typically clustered or linear. Urticaria pigmentosa (mast cell syndrome).

Resources

Core EM

Take Home Points: Airway management is paramount, expect a challenging intubation and consider controlling the airway early. Understanding the cause of angioedema (mast cell vs. bradykinin mediated) helps dictate directed management. Urticaria and pruritus = MAST CELL mediated, which is treated like a standard allergic reaction.

EMCrit

If you're going to choose an expensive drug for treatment of bradykinin-mediated angioedema, C1-esterase concentrate seems to be supported by a greater amount of evidence and experience.

Life in the Fastlane

ACE Inhibitors (ACEI) •up to 1% incidence •angioedema is a class effect and is not dose dependent – symptoms can occur any time from a few hours up to 10 years after the initial dose (Winters et al, 2013) •more common in African Americans and patients on immunosuppressants •note that angioedema can occur in patients switched to an angiotensin receptor blocker