Blood pressure is normally taken on the upper arm at the level of the heart. Sup

Question

Blood pressure is normally taken on the upper arm at the level of the heart. Suppose, however, that a patient has his arms in a cast so you cannot take his blood pressure in the usual way. If you have him stand up and take the blood pressure at his calf, which is 87.5 cm below his heart, what would be the magnitude of the difference between this measurement of blood pressure and a normal blood pressure measurement? The density of blood is 1060 kg/m3.

Is the blood pressure measured in the calf larger or smaller than the blood pressure measured on the upper arm?

Explanation / Answer

Let pressure at heart be P0

Then pressre at calf = P = P0 - d* g * h

Pressure difference = (P0 -d*g*h ) -(P0) = -d*g*h =(1060 kg/m^3) * ( 9.81m / s^2) * ( 0.875 m) = -9098.775 Pa

This blood pressure at calf is smaller than the blood pressure measured on the upper arm

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects