It is a measure of the pressure exerted by blood on the artery walls in its drive through the arteries. Because the blood moves in waves, two types of measures of pressure:
Systolic pressure is the blood due to contraction of the ventricles, ie the maximum pressure and the diastolic pressure is the pressure that remains when the ventricles relax, this is the minimum pressure.
The mean arterial pressure (MAP) was calculated using the following formula: systolic pressure – diastolic pressure / 3 + diastolic pressure. The PA is determined by cardiac output and peripheral vascular resistance, hence the PA reflects both the stroke volume of blood as the elasticity of arterial walls.
- The arm and forearm should be naked, or at least the clothes should not exert improper compression.
- The cuff size should be chosen according to the diameter of the arm. The relative disparity between the size of the arm and the cuff may be cause of error, in very obese arms usually falsely elevated values are obtained very thin arms and obtained values below normal.