Question

Why would hydrostatic blood pressure in blood vessels decrease due to vascular resistance?

Answer 1

Hydrostatic pressure is the force exerted by a fluid due to gravitational pull, usually against the wall of the container in which it is located. One form of hydrostatic pressure is blood pressure, the force exerted by blood upon the walls of the blood vessels or the chambers of the heart. This hydrostatic pressure depends upon the blood flow to that particular tissue or the whole circulation in general.

Five variables influence blood flow and blood pressure:

• Cardiac output
• Compliance
• Volume of the blood
• Viscosity of the blood
• Blood vessel length and diameter

An increase in vascular resistance is actually an:

1. Increase in cardiac output
2. Decrease in compliance
3. Increase in volume of blood
4. Increase in viscosity of blood
5. Increase in length and decrease in diameter of vessel

These all factors cause a decrease in the blood flow and thus decrease the hydrostatic pressure.