What type of shock will develop after patient develops allergic reaction to a vaccine
Reading Document
Medical Text Search
anaphylactic shock allergic reaction vaccine pathophysiology
GradeResponse
An allergic reaction to a vaccine causes anaphylactic shock (also called distributive shock due to anaphylaxis).
Anaphylactic Shock Following Vaccine Allergic Reaction
Type of Shock
Anaphylactic shock is a subtype of distributive shock. It is characterized by massive vasodilation and increased vascular permeability triggered by an acute systemic allergic (hypersensitivity) reaction.
Pathophysiology
When a sensitized individual receives a vaccine, the following cascade occurs:
- Antigen recognition — IgE antibodies on mast cells and basophils recognize the allergen (vaccine component, excipient, adjuvant, or stabilizer).
- Mast cell/basophil degranulation — Cross-linking of IgE triggers release of:
- Histamine
- Tryptase
- Leukotrienes
- Prostaglandins
- Systemic effects:
- Vasodilation → decreased systemic vascular resistance (SVR)
- Increased capillary permeability → fluid shifts out of the vasculature
- Relative hypovolemia → decreased preload
- Bronchospasm → airway compromise
- Result: Distributive shock with hypotension, tachycardia, and potential cardiovascular collapse
According to Harrison's Principles of Internal Medicine, 21st Edition (p. 9922), anaphylaxis is a potentially life-threatening systemic allergic reaction involving one or more organ systems, typically occurring within seconds to minutes of exposure to the trigger.
Key Features of Anaphylactic Shock
| Feature | Detail |
|---|---|
| Onset | Seconds to minutes post-exposure |
| Hemodynamics | ↓ BP, ↑ HR, ↓ SVR |
| Skin | Urticaria, flushing, angioedema |
| Respiratory | Bronchospasm, stridor, laryngeal edema |
| GI | Nausea, vomiting, cramping |
| Mechanism | IgE-mediated (Type I hypersensitivity) |
First-Line Treatment
- Epinephrine (IM, 0.3–0.5 mg into the lateral thigh) — reverses vasodilation, bronchospasm, and mast cell mediator release
- IV fluids for volume resuscitation
- Supplemental oxygen / airway management
- Antihistamines (H1 + H2 blockers) as adjuncts
- Corticosteroids to prevent biphasic reaction
- Patient should be monitored for 4–6 hours due to risk of biphasic anaphylaxis (recurrence without re-exposure)
Bottom line: A severe allergic reaction to a vaccine produces anaphylactic shock, classified under distributive shock, driven by IgE-mediated mast cell degranulation causing systemic vasodilation and vascular leak.
This is a shared conversation. Sign in to Orris to start your own chat.