The mean arterial pressure, often abbreviated as MAP, is a central parameter in medicine, particularly in intensive care medicine. It represents the average pressure in the arteries over an entire cardiac cycle and is crucial for assessing organ perfusion.
Definition
The MAP is usually expressed in mmHg and can be calculated as follows:
MAP = (2 x Diastole + Systole)/3
This formula is based on the assumption that the heart is in systole for about one-third of the time and in diastole for two-thirds. As a result, the diastolic value is weighted twice.
Clinical Relevance
The MAP has significant clinical importance because it serves as an indicator of perfusion. A sufficiently high MAP is essential to ensure the blood flow to vital organs such as the brain, heart, and kidneys. In intensive care medicine, MAP is therefore closely monitored to ensure adequate organ perfusion.
A particular application area of MAP in neurosurgery is the calculation of the cerebral perfusion pressure (CPP), which is crucial for assessing brain perfusion. The CPP is the difference between the MAP and the intracranial pressure (ICP). An adequate CPP is essential for maintaining brain functions and preventing ischemic brain damage.