Which of the following symptoms might indicate anaphylactic shock in a casualty?

Anaphylactic shock is a severe and potentially life-threatening allergic reaction that occurs rapidly after exposure to an allergen. One of the hallmark symptoms of anaphylaxis includes bronchospasm, which is the tightening of the muscles around the airways, leading to difficulty in breathing. This can manifest as wheezing or shortness of breath. Additionally, vasodilation is a key component of anaphylaxis, where blood vessels widen, resulting in a drop in blood pressure and potentially contributing to shock.

These physiological responses occur because the body's immune system overreacts to a harmless substance (the allergen), releasing chemicals such as histamines that lead to these symptoms. The combination of bronchospasm, which restricts airflow, and vasodilation, which affects the circulatory system, directly corresponds to the dangerous nature of anaphylaxis, emphasizing the need for immediate medical attention.

The other options include symptoms that are not characteristically associated with anaphylactic shock. For instance, a severe headache and numbness could suggest other conditions but are not typical indicators of this allergic reaction. Similarly, dehydration and fever suggest other medical issues that do not align with the acute symptoms of anaphylaxis. Rapid heart rate and high blood pressure can be seen in various