What is a common symptom of a vagal reaction during a cardiac procedure?

A common symptom of a vagal reaction during a cardiac procedure is diaphoresis, which refers to excessive sweating. This reaction is typically triggered by stimulation of the vagus nerve, leading to a sudden drop in heart rate (bradycardia) and a decrease in blood pressure. The body compensates for this response, and one of the manifestations can be significant sweating as a way to regulate body temperature and fluid balance.

Diaphoresis can also be reflective of the body's stress response to the discomfort or anxiety associated with the procedure. In contrast, flushed skin is more often associated with vasodilation, while an increased heart rate typically indicates the body's fight-or-flight response rather than a vagal reaction. Persistent headache is not a characteristic symptom of a vagal response during cardiac procedures, making diaphoresis the most relevant choice in this context.