Occlusion of common carotid aeries on both sides leads to
Occlusion of both common carotid aeries causes an increase in HR and BP. Reduced sinus pressure - response carried to nucleus tractus solitarius glossopharyngeal and vagus nerve -less inhibitory effect on the vasomotor center. Decreased parasympathetic activity to the hea- increases hea rate. Increased sympathetic activity to the hea and blood vessels - increases hea rate, contractility, constricts aerioles - increases TPR, constricts veins- increases venous return. The carotid baroreceptors are located in the walls of the carotid sinus, which is located at or slightly above the bifurcation of the common carotid aeries. So, the occlusion of common carotid aeries is occlusion proximal to the carotid sinus. If the occlusion is distal to the carotid sinus -increase in sinus pressure - activation of baroreceptor reflex- decrease in BP and HR. Ref: Guyton and Hall 13th edition Pgno: 166
Increase in hea rate and BP
Increase in BP and decrease in hea rate
Decrease in hea rate and BP
No effect on hea rate and BP
Cardiovascular system