Ace the Ontario Paramedic Practice Exam 2025 – Sprint to Success and Save Lives!

The correct answer describes typical cardiovascular presentations during an allergic reaction, particularly in the case of anaphylaxis. Anaphylaxis is a severe and potentially life-threatening allergic reaction that can lead to a series of cardiovascular symptoms.

In anaphylaxis, the body's response to the allergen causes a release of mediators like histamine, which can lead to vasodilation and increased vascular permeability. This results in a decrease in blood pressure (hypotension) and can cause an increase in heart rate (tachycardia) as the body attempts to compensate for the dropping blood pressure. The decrease in blood perfusion can lead to syncopal episodes (loss of consciousness) and may result in a decrease in level of consciousness (LOC) due to inadequate blood flow to the brain. Hypoxemia is also a concern, as airway compromise may occur, further impacting oxygen levels.

This understanding of the physiological responses during an allergic reaction highlights the importance of recognizing these changes in cardiovascular function, enabling prompt and effective intervention in emergency situations.