Question

explain 3 ways that cardiac output and total peripheral resistance are altered to affect blood pressure.

Answer 1

1) If blood pressure decreses --> Baroreceptor signal--> Increased sympthetic and decresed parasympathetic outflow --> Tachycardia & vasoconstriction--> Increased peripehral resistance --> Increases venous return--> Increases cardiac output --> BP returns back to normal.

2) When BP Increases - Baroreceptor signals - Increased parasympathetic and decreses sympthetic signals --> Bradycardia and vasodilation --> Blood remain in complaint venous system--> Decreased venous return and hence Decreased cardiac output --> BP returns back to normal

3) In case of blood loss, blood is diverted to vital organ and vasoconstriction occurs in skin and skeletal muscle -> Increased TPR --> Increased venous retrun --> Increases BP

4) During exercise to meet the demand of exercising muscle vasodilation in the skeletal muscle vasulature lead to decrased peripheral resistance. Also contractility of heart is Increased by sympthetic stimulation --> Hence Increased cardiac output. BP is maintained due to vasodilation i.e. decresed TPR.