Here’s another one to add to your “scary things that can happen to patients” list, and that, my friends, is angioedema. But, with a little knowledge ahead of time, you’ll hopefully recognize when it happens and know what to do for your patient.

Angioedema is a sudden, non-pitting edema of the skin and mucous membranes. You’ll typically see angioedema in the upper respiratory and GI tracts, though it’s detrimental effects on airway patency are what make it potentially life-threatening.

In angioedema, histamines or bradykinins are released as part of an allergic or anaphylactic response, and this causes an abrupt increase in capillary permeability. This could be a reaction to a food, drug or other substance. Common drugs that can cause angioedema are ACE inhibitors (lisinopril), NSAIDS (ibuprofen, naproxen, aspirin) and antibiotics.

​​In addition to allergy-induced angioedema, patients can experience hereditary angioedema and chronic, idiopathic angioedema as well.

You can maximize your learning by also listening to the accompanying podcast episode on angioedema (episode 192) right from this website, or search the Straight A Nursing podcast wherever you get your podcasts.

Let’s go through angioedema using the Straight A Nursing LATTE method.

L: How does the patient LOOK?

  • The most prevalent indicator of angioedema is the presence of edema, particularly in the face, hands, feet and genitalia. Swelling of the lips and eyes is considered the “classic” sign of angioedema.
  • Some patients will have an accompanying urticaria
  • Numbness or tingling may be present at sites with extreme swelling. 
  • They may be anxious or nervous.
  • Diaphoresis may be present.
  • If the patient is struggling to breathe, they may be pale with dusky lips. 
  • Due to swelling around the eyes, the patient may state they have difficulty seeing.

A: How do you ASSESS the patient?

  • Your priority assessment with angioedema is airway patency. In fact, any time your patient has swelling of the head, neck, face, mouth, lips, tongue….airway should always be top of mind. 
  • Monitor severity of the edema, especially as it relates to the face, head, and neck.
  • Assess CSM of hands and feet for any neurovascular abnormalities such as delayed capillary refill or numbness/tingling. 
  • Monitor HR, blood pressure, and respiratory rate to ensure that the patient is remaining stable and no further interventions are needed. 
  • Assess vision. The swelling may impede eyesight and create a safety concern. 

T: What TESTS will be conducted?

Which tests are ordered will be dependent upon whether the angioedema has been triggered by a known substance or idiopathic in nature. 

  • C1-INH levels – to determine whether or not a deficiency is present (a deficiency would indicate that hereditary or acquired angioedema is present).
  • CBC –  to monitor blood counts for presence of infection
  • C-reactive protein and ESR – both are indicators of inflammation; CRP may be elevated in ACE inhibitor-induced angioedema
  • Urinalysis – to check for a UTI, which may occur when the mucosal lining of the urinary tract is affected
  • Serum tryptase – elevations indicate the angioedema is a mast-cell mediated event, which is typical in angioedema with anaphylaxis
  • Allergy testing may be conducted if the angioedema is due to a suspect allergen
  • Imaging studies of the bowel may be conducted if the GI tract is involved and can include CT or ultrasound. A multidetector CT scan can also be conducted to determine if GI tract edema is a result of ACE inhibitor-induced angioedema, presenting unnecessary surgery in these patients.
  • Thyroid studies may be performed, especially in women or those with family history of thyroid disease and/or autoimmune disorders. Studies show that autoimmune thyroid disease is strongly associated with angioedema.

T: What TREATMENTS will be provided?

How angioedema is treated depends on the severity, acuity and mechanism.

  • If the airway is involved, the patient may require intubation for airway protection.
  • Angioedema secondary to ACE inhibitors typically involves stopping the medication and protecting the airway until symptoms resolve.
  • Angioedema secondary to anaphylaxis will likely be treated with IM epinephrine, oxygen administration and IV fluids.
  • Allergy-induced (mast-cell mediated)  angioedema that is not anaphylaxis is typically treated with antihistamines and corticosteroids. 
  • If the angioedema is hereditary in nature, treatments can include C1 inhibitor concentrate, medications that inhibit kallikrein or antagonize bradykinin, or even FFP though it’s important to note that in some cases FFP can make the angioedema worsen acutely and is utilized with extreme caution.
  • Recurrent angioedema may be treated with nonsedating antihistamines. Some patients may also require a leukotriene receptor antagonist. Severe cases that are resistant to treatment may require a bradykinin-B2-receptor antagonist or monoclonal antibody therapy.

E: HOW DO YOU EDUCATE THE PATIENT/FAMILY? 

  • Once the trigger has been identified, patients should avoid it as much as possible to prevent another episode. 
  • Patients with anaphylaxis-related angioedema should always carry an EpiPen
  • Teach the patient the signs of angioedema and to call for emergency help if they have difficulty breathing or swallowing, nausea/vomiting, abdominal cramps, swelling of the neck, lips or tongue, or a tight feeling in the throat
  • If a diagnosis of hereditary angioedema is made, continue to follow up and check C1-INH levels regularly to prevent another episode

SUMMARY

The key must-know information for angioedema is: 

  • It involves acute swelling of the tissue under the skin and is most concerning when it includes the face, mouth, tongue, and neck
  • The priority assessment is airway patency
  • The priority intervention is airway patency and intubation may be necessary
  • Common pharmacologic treatments include epinephrine, corticosteroids and antihistamines
  • Angioedema can be hereditary, idiopathic, due to an allergy, or drug-mediated
  • Common drugs that cause angioedema include ACE inhibitors, antibiotics and NSAIDS

Listen to episode 192 of the Straight A Nursing podcast to review the nursing management of angioedema on the go.

REFERENCES

Delves, PhD, P. J. (2020, October). Angioedema. Merck Manuals Professional Edition; Merck Sharp & Dohme Corp. https://www.merckmanuals.com/professional/immunology-allergic-disorders/allergic,-autoimmune,-and-other-hypersensitivity-disorders/angioedema

Greiner, B., Pelton, J., & Baker, D. (2020). Hypothyroidism-associated angioedema. Proceedings (Baylor University. Medical Center), 33(2), 254–255. https://doi.org/10.1080/08998280.2020.1724847

Huamin, MD, PhD, H. L. (2018, September 4). Angioedema workup: Approach considerations, laboratory studies, allergy testing. Medscape; WebMD. https://emedicine.medscape.com/article/135208-workup#c1

Kaplan A. P. (2008). Angioedema. The World Allergy Organization journal, 1(6), 103–113. https://doi.org/10.1097/WOX.0b013e31817aecbe

Zuraw, B. (n.d.). An overview of angioedema: Clinical features, diagnosis, and management. UpToDate. Retrieved December 2, 2021, from https://www.uptodate.com/contents/an-overview-of-angioedema-clinical-features-diagnosis-and-management?search=angioedema&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H25