How is mean arterial pressure at rest calculated?

Mean arterial pressure (MAP) is a crucial physiological metric that provides insights into the average blood pressure in a person's arteries during one cardiac cycle. It is more representative of tissue perfusion than systolic or diastolic blood pressure alone.

The correct calculation for MAP at rest involves using diastolic blood pressure and taking into account the pulse pressure, which is the difference between systolic and diastolic blood pressure. The formula that accurately captures this relationship is:

Mean Arterial Pressure = Diastolic Blood Pressure + (0.33 x Pulse Pressure)

Here, pulse pressure is defined as the difference between systolic and diastolic blood pressure. The 0.33 factor is utilized because it effectively weights the time the heart spends in diastole compared to systole, given that the heart remains in diastole for approximately two-thirds of the cardiac cycle when at rest.

This means that while the systolic pressure reflects the peak pressure in the arteries when the heart beats, and diastolic pressure reflects the lowest pressure, the mean arterial pressure represents a more stable average pressure that is critical for ensuring adequate blood flow to organs and tissues at rest.

Therefore, option B provides the correct formula for calculating mean arterial pressure at rest