Allergic Reactions and Anaphylaxis:

Definition/Etiology:

We all know that an allergic reaction is a response by the body’s immune system to an exposure to an antigen. The most common ones are antibiotics, insect bites and stings, foods, and environment. The most severe reaction is, of course, anaphylaxis, which can cause complete airway obstruction pretty quickly.

Pathophysiology:

OK so we don’t have the time to go through the full patho of allergic reactions, and frankly, CEN likely will not ask about the patho on this, so just know that allergic reactions are the body’s response to an antigen. The reaction involves IgE cells, T cells, B cells, CD4 cells….a whole bunch of cells that are basically trying to protect the body from a perceived threat. If you want to know more, you can check the article in the reference section.

Clinical Presentation:

• The presentation of these patients can be from mild to severe and we have all seen the spectrum. Any of the following (or frankly all of the following) can be present.
• Flushed skin
• Hives
• Urticaria
• Coughing
• Sneezing
• Dyspnea
• Facial and upper airway edema
• Muffled voice
• Wheezing
• Stridor
• N/V/D

Collaborative Management:

Our treatment here will depend on the severity of the reaction. If someone comes in with some simple hives, they may be discharged just with a prescription and some well wishes. On the other hand, if they are in full blown anaphylaxis, well then, time to go to work!

• Allow positioning for comfort and air exchange
• High flow O2
• IV access (don’t get me started on small gauge)
• Cardiac and O2 sat monitoring
• Grab the emergency airway cart, just in case.
• Prep for intubation
• Anticipate meds:
  • Bronchodilators
  • Epi – sub-Q for moderate reactions, IV for more severe
  • Antihistamines – Benadryl
  • H2 blockers – Pepcid
  • Corticosteroids

Evaluation | Patient Monitoring | Education:

Our effectiveness of treatment will be determined by the patient’s response. If they are having difficulty breathing…we want them to have less difficulty. If they have hives and urticaria, we want to lessen these symptoms. Honestly, an allergic reaction is one of the conditions where we can see a positive response fairly quickly.

One of the most important things to remember is just because we have resolution of symptoms after our initial treatments, DON’T LET THEM LEAVE. Especially if we are unsure of what triggered the reaction. Usually after symptoms begin to resolve, we want to hold on to these patients for a few hours….why?

That’s right, to make sure the reaction does not rebound when the meds wear off!

As far as education here, it can be difficult if we don’t know what caused the reaction. If we do.. well, it’s fairly simple… stay away from that thing!

Linchpins: (Key Points)

• What?
• Act fast
• Prep for anything