Blood Pressure Guidelines

Medical Author: Benjamin C. Wedro, MD, FACEP, FAAEM
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

The concept of blood pressure is sometimes difficult to understand because it is usually described with numbers. However, adequate pressure within arteries is important to allow blood to be pumped throughout the body to deliver oxygen and other nutrients to areas of the body. This allows for normal metabolism and organ function.

The blood pressure recording, measures pressures within the arteries at two different times. The first reading, the systolic pressure, measures the pressure when the heart is pumping blood to the body through the arteries. The second reading, the diastolic pressure, measures the pressure within the arteries when the heart is receiving blood returning from the body.

There needs to be an underlying pressure within arterial blood vessels regardless of whether the heart is pumping or not. This intrinsic pressure is maintained by smooth muscle cells that surround all artery walls, great and small, and in effect squeeze and support the walls. Without this wall support, arteries would collapse in diastole (between each heart beat).

Picture of the systolic and diastolic pressure systems of measuring blood pressure

Blood pressure measurement is listed with two numbers with normal being less than 120/80, with 120 being the systolic blood pressure when the heart is pushing blood through the arterial system; and 80 being the diastolic blood pressure when the arteries are at rest and the heart is refilling.

Medically Reviewed by a Doctor on 12/1/2014