How to Calculate Minimum Heart Blood Pressure for Brain Arterial Pressure?

[jmandas]

okay having trouble setting up the formula for this one! So if someone could just tell me what formula to use that would be awesome.

What minimum blood pressure in mmHg at the heart is required to produce an artial blood pressure of 59 mmHg in the brain if the brain is 34 cm above the heart and blood density is 1.05g/cm^3. You may neglect pressure drops due to resitance.

Formula I've been attemting to use:
First I tried P(heart)=P(brain)-(height)(p which is blood density)(g)
Didn't work so tried P= hpg/P(brain)
then tried P=P(brain)/hpg

Answer should be 85.3mmHg

 

[dextercioby]

There's a similar problem posted earlier...I gave you the advice to use the formula that u have,but pay attention with the units.

Daniel.

 

[thepatientmental]

Hi there,

Thank you for sharing your question about the blood pressure problem. The formula you are looking for is called the hydrostatic pressure formula, which is:

P = ρgh

Where:
P = pressure (in mmHg)
ρ = blood density (in g/cm^3)
g = acceleration due to gravity (9.8 m/s^2)
h = height difference between the heart and brain (in cm)

Using this formula, we can solve for the minimum blood pressure at the heart:

P(heart) = P(brain) + ρgh

P(heart) = 59 mmHg + (1.05 g/cm^3)(9.8 m/s^2)(34 cm)

P(heart) = 85.3 mmHg

Therefore, the minimum blood pressure at the heart required to produce an arterial blood pressure of 59 mmHg in the brain is 85.3 mmHg.

I hope this helps and clarifies the formula for you. Let me know if you have any other questions. Best of luck!