Sometimes referred to as Quinke's Edema, angioedema is that swelling we see that is most apparent around the mucosal areas of the face. Consider Hives as swelling on the surface of the skin, and angioedema as swelling beneath the skin.
The most common cause of this type of swelling without the presence of Hives is hypersensitivity to ACE inhibitors.
ACE = Angiotensin converting enzyme. This converts angiotensin one into angiotensin two.
ACE inhibitors block ACE.
Bradykinin is a peptide that has a role with all forms of angioedema. It is a potent vasodilator that increases permeability and allows the accumulation of fluid within the interstitial space.
ACE is one of the main ways that bradykinin is degraded. So when we inhibit the production of ACE, we are then inhibiting the degradation of bradykinin. We then have this run away peptide and subsequent swelling.
Many patients that suddenly present with severe angioedema have been taking ACE inhibitors, such as lisinopril, for a long period of time. They may have never had any issues before, but out of no where have this severe reaction. This type of reaction is most common in the African-American population, but may occur in anyone.
There are other types of angioedema, including the traditional allergic reaction. Those are more well known and prepared for.
As you can see from the pictures above, swelling may be within the oropharynx. This can cause an airway obstruction, and aggressive airway management should be advocated.
This patients may be obtunded and snoring as you enter the scene. They have been confused for diabetics, or acute coronary syndrome patients due to their initial impression.
It is common for these patients to undergo cricothyrotomy due to complete glottic obstruction. Moving quickly is imperative to prevent severe hypoxia and cardiorespiratory arrest.
The usual drugs used for anaphylactic reactions are indicated.
- Epinephrine to reduce the vasodilation.
- Crticosteroids & antihistamines.
So the next time you run on a patient that is presenting with swelling in the absence of hives, think angioedema, and act fast!