Mean arterial pressure (MAP) is a key reading doctors use to assess blood flow through your body. It’s related to your systolic and diastolic blood pressure readings but accounts for flow and resistance.

Automatic blood pressure monitors give you a systolic and diastolic blood pressure reading. Many of them also include a small number in parentheses underneath or beside your standard blood pressure reading. This number in parentheses is the mean arterial pressure (MAP).

MAP is a calculation that doctors use to check whether there’s enough blood flow to supply blood to all your major organs. Too much resistance and pressure may impede that flow.

“Resistance” refers to the way the width of a blood vessel impacts blood flow. For example, it’s harder for blood to flow through a narrow artery. As resistance in your arteries increases, blood pressure also increases while the flow of blood decreases.

You can also think of MAP as the average pressure in your arteries throughout one cardiac cycle, which includes the series of events that happen every time your heart beats.

Keep reading to learn more about the normal, high, and low ranges of MAP and what they mean.

In general, most people need a MAP of at least 60 mm Hg (millimeters of mercury) or greater to ensure enough blood flow to vital organs, such as the heart, brain, and kidneys. Doctors usually consider anything between 70 and 100 mm Hg to be normal.

A MAP in this range indicates that there’s enough consistent pressure in your arteries to deliver blood throughout your body.

A high MAP is anything over 100 mm Hg, which indicates that there’s a lot of pressure in the arteries. This can eventually lead to blood clots or damage to the heart muscle, which has to work a lot harder.

High blood pressure can put people at risk for a number of conditions. These can also lead to a high MAP and they include:

Anything under 60 mm Hg is usually considered a low MAP. It indicates that your blood may not be reaching your major organs. Without blood and nutrients, the tissue of these organs begins to die, leading to permanent organ damage.

Low blood pressure puts people at risk for certain conditions, and these can also lead to a low MAP. They include:

In order to calculate your MAP, you need to know your diastolic blood pressure (DBP) and systolic blood pressure (SDP) values. You then follow this equation: 1/3(SBP)+2/3(DBP).

In some cases, in the hospital, a doctor may place a central line in a person and use that to determine the values of cardiac output, central venous pressure, and systemic vascular resistance. They may then use these other values to calculate a person’s MAP. However, an actual calculation is not always necessary as there is typically a machine that also provides the MAP reading automatically.

You can also calculate a MAP value automatically here.

An unusual MAP is usually a sign of an underlying condition or problem in the body, so the treatment depends on the cause. causes may include heart conditions, Sepsis, stroke, internal bleeding, and more.

For a low MAP, treatment may focus on safely raising blood pressure quickly to avoid organ damage. This is usually done with:

  • intravenous fluids or blood transfusions to increase blood flow
  • medications called “vasopressors” that tighten blood vessels, which can increase blood pressure and make the heart beat faster or pump harder

Depending on the cause, treating a high MAP may also require quick action, in this case, to reduce overall blood pressure. This can be done with oral or intravenous nitroglycerin (Nitrostat). This medication helps to relax and widen blood vessels, making it easier for blood to reach the heart.

Once the blood pressure is under control, the doctor can continue treating the underlying cause. This may involve:

  • breaking up a stroke-causing blood clot
  • inserting a stent into a coronary artery to keep it open

MAP is an important measurement that accounts for flow, resistance, and pressure within your arteries. It allows doctors to evaluate how well blood flows through your body and whether it’s reaching all your major organs.

Most people do best with a MAP between 70 and 110 mm Hg. Anything much higher or lower can be a sign of an underlying problem. However, this is typically most applicable as a measurement for inpatient procedures and hospitalized patients.