Which of the following is a contraindication for electrotherapy when considering the carotid sinus area?

• A. Over carotid sinus
• B. Over a non-sensitive area
• C. Under a protective shield
• D. Near a bone surface

Answer: (A)

Stimulation of the carotid sinus can trigger a reflex that slows the heart and lowers blood pressure. Because of this, applying electrotherapy directly over the carotid sinus is avoided. The carotid sinus contains baroreceptors that, when irritated electrically, can initiate a parasympathetic response through the vagus nerve, leading to bradycardia and hypotension, with potential dizziness, syncope, or cerebral hypoperfusion. This makes the area a contraindicated site for electrotherapy.

Locations described as safe in other contexts—over a non-sensitive area, under a protective shield, or near a bone surface—do not inherently carry the same risk of triggering this reflex, so they are not contraindicated for this reason.