Question

In terms of the following formula (MAP=CO x R), what do systolic and diastolic pressures represent?

Systolic:

Diastolic:

What is the reason for this?

a)No, because one measures pressure in the ventricles and the other the resistance in the capillaries.

b)Yes, because they are both measures of pressure in arterial blood vessels.

c)No, because systolic and diastolic values represent very different physiological processes.

d)Yes, because you are using the same cuff to measure both pressures.

e)No, because systolic measures the heart at rest and the diastolic value describes what is happening during the contraction phase.

not an incomplete question.

Answer 1

MAP = (C.O × SVR ) + CVP

CVP = 0

MAP = C.O × SVR

SVR = Systemic vascular resistance

In practice, MAP is not determined by knowing the CO and SVR, but rather by direct or indirect measurements of arterial pressure. From the aortic pressure trace over time (see figure), the shape of the pressure trace yields a mean pressure value (geometric mean) that is less than the arithmetic average of the systolic and diastolic pressures as shown to the right.

At normal resting heart rates, MAP can be approximated by the following equation

MAP = Pdia + 1/3(P sys - P dia )

B) yes, both measures the pressure in the atrial blood vessel

The top number refers to the amount of pressure in your arteries during the contraction of your heart muscle. This is called systolic pressure.

The bottom number refers to your blood pressure when your heart muscle is between beats. This is called diastolic pressure