All the following are characteristic feature of anaphylactic shock EXCEPT
**Core Concept**
Anaphylactic shock is a severe, life-threatening allergic reaction that occurs within minutes of exposure to an allergen, characterized by a constellation of symptoms including vasodilation, increased vascular permeability, and bronchospasm. It is mediated by the release of histamine and other chemical mediators from mast cells.
**Why the Correct Answer is Right**
The correct answer is a feature that is not characteristic of anaphylactic shock. In contrast, anaphylactic shock is typically associated with symptoms such as **hypotension**, **tachycardia**, and **bronchospasm**. The release of histamine and other chemical mediators leads to vasodilation and increased vascular permeability, resulting in decreased blood pressure and potential respiratory compromise.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is a characteristic feature of anaphylactic shock, as it is often accompanied by **hypotension** due to vasodilation and decreased vascular tone.
**Option B:** Tachycardia is a common response to anaphylactic shock, as the body attempts to compensate for the decreased blood pressure.
**Option C:** Bronchospasm is a hallmark of anaphylactic shock, particularly in individuals with pre-existing asthma or other respiratory conditions.
**Clinical Pearl / High-Yield Fact**
One key point to remember is that anaphylactic shock can be reversed with prompt administration of epinephrine, which helps to mitigate the effects of histamine and other chemical mediators on the cardiovascular and respiratory systems.
**Correct Answer: D**