Blood Pressure and Its Control Mechanism

Abstract

Arterial blood pressure is the lateral pressure exerted by the column of blood against the arterial walls. During the cardiac cycle the highest pressure attained is the sys-tolic pressure and the lowest pressure is the diastolic pressure. The mean blood pressure (MBP) is the geometric mean, and calculation of MBP requires integration of pressure pulse. However, a crude estimate of MBP is given by the following formulas: 1. MBP = [systolic pressure + 2 (diastolic pressure)]/3. 2. MBP = diastolic pressure + (pulse pressure)/3. Pulse pressure is the difference between the systolic and di-astolic pressures. The MBP (in millimeters of mercury) is the product of cardiac output (liters per minute) and total peripheral resistance (millimeters of mercury per liter per minute).