Cardiac Vascular Nursing Certification Practice Exam 2025 - Free Cardiac Vascular Nursing Practice Questions and Study Guide

The formula for calculating Mean Arterial Pressure (MAP) is critical in assessing overall blood flow to organs and tissues. The correct calculation is derived from the understanding that MAP represents the average pressure in a person's arteries during one cardiac cycle.

The formula involves taking the diastolic blood pressure and adding one-third of the difference between the systolic and diastolic pressures. This is represented mathematically as:

MAP = Diastolic + 1/3(Systolic - Diastolic)

When this is simplified, it can be expressed in a form that looks similar to option A, particularly when rearranging terms. The significance of this formula is rooted in the fact that the heart spends more time in diastole (the relaxation phase) than in systole (the contraction phase). Thus, the weighted average correctly reflects the blood pressure profile over the whole cycle, accounting for the longer duration of diastole.

Other options do not reflect the proper understanding of cardiovascular dynamics or do not consider how diastolic and systolic pressures relate in terms of time and physiological relevance.