In-Depth Notes on Allergy and Anaphylaxis for EMTs

National EMS Education Standard Competencies

  • EMTs apply fundamental knowledge to provide emergency care based on assessment findings, particularly for acutely ill patients.
  • Recognition and management of allergic reactions and anaphylaxis are critical.

Importance of Understanding Immunology

  • Immunology: the study of the immune system's response to foreign substances.
  • Key aspects:
    • Emergency response to allergic reactions can involve acute airway obstruction and cardiovascular collapse.
    • EMTs need to distinguish between normal reactions and severe allergic reactions to allergens.

Anatomy and Physiology

  • The immune system defends against foreign substances:
    • Upon invasion, it initiates responses (e.g., histamine release) to disable the invader.

Pathophysiology of Allergic Reactions

  • Definition: An allergic reaction is an exaggerated immune response against a seemingly harmless substance.
  • Common mediators involved:
    • Histamines: Cause allergy symptoms.
    • Leukotrienes: Contribute to inflammation and respiratory issues.
  • Anaphylaxis: A severe form of allergic reaction affecting multiple organ systems, can lead to shock and death.
    • Signs include urticaria (hives), angioedema (localized swelling), wheezing, and hypotension.

Common Allergens

  1. Food: e.g., shellfish and nuts - can take time to react.
  2. Medications: e.g., penicillin - immediate reactions possible with injections.
  3. Plants/Pollens: e.g., ragweed, oak.
  4. Chemicals: e.g., latex and cleaning agents.
  5. Insect Stings: Can be systemic with severe reactions. Around 2 million Americans are allergic.

Patient Assessment in Allergic Reactions

  • Scene Size-up: Assess environment for allergens (food, insects, medication).
  • Primary Assessment:
    • Assess immediate life threats including airway and circulation.
    • Watch for signs of respiratory distress (e.g., stridor, wheezing).
  • Hypotension can occur due to vasodilation during anaphylactic shock.

Treatment Strategies

  • Administer high-flow oxygen if necessary.
  • Use epinephrine to counteract anaphylaxis:
    • Adult dosage: 0.3 mg; Child dosage: 0.15 mg, delivered via auto-injector.
  • Follow protocols and provide prompt transport to medical facilities.

Symptoms and Signs of Anaphylaxis

  • Initial symptoms can include:
    • Sneezing, tightness in chest, shortness of breath.
    • Progressive symptoms such as angioedema, increased heart rate, hypotension.
  • Anaphylactic shock can lead to clinical deterioration quickly, often within minutes.

Communication and Documentation

  • Maintain a clear record of symptoms, treatment provided, and patient response.
  • Significant for ensuring continuity of care and effective emergency treatment.