Types

• Blood pressure (BP) refers to the amount of sustained pressure created by the blood being pumped by the heart. A healthy BP is a vital sign of life. Systolic and diastolic BP are the names given to differentiate the types of pressure and their corresponding roles: systolic refers to the force of oxygenated ("fresh") blood being pumped by the heart to the rest of the body. Diastolic is the force being returned to the heart to get oxygenated by the lungs before being shipped out again as fresh blood.
  
  

What It Does

• Systolic is a high pressure system that uses arteries and capillaries to push the blood out to the tissues and organs. Diastolic is much lower in pressure, as the veins carry the de-oxygenated blood back to the heart. Veins are also segmented, which ensures that the blood takes a leisurely pace back to the heart while arteries (and arterioles) are internally smooth, allowing for faster and unimpeded travel.
  
  

Measuring BP

• The sphygmomanometer--medical long hand for the blood pressure cuff--is the most common method, measuring both systolic and diastolic BP via the cuff, which squeezes and slowly releases the arm until the dial can register the BP number. By restricting blood flow, the cuff picks up the systolic at its peak pressure moment; slowing letting the flow continue reads the diastolic, the moment right before a blood pump when the ventricles are filling with blood.
  
  

Significance

• To understand BP anomalies, doctors refer to BP numbers set against standardized norms according to age group (as BP usually increases slightly with age). The average systolic range for adults runs between 90 to 119, whereas the diastolic falls in the 60 to 79 range. Hypotension, or low blood pressure, is suspected when systolic falls lower than 90 and diastolic reads less than 60. Hypertension, or high blood pressure, is divided into three separate distinctions. Pre-hypertensive (conditions that suggest the development of hypertension) is diagnosed when BP reads 120 to 139 systole and 80 to 89 diastole. Actual hypertension, a serious condition, lies above these numbers.
  
  

Warning

• Stage 1 hypertension occurs when systolic reads 140 to 159 and diastole measures 90 to 99. Any numbers greater than those are considered Stage 2 hypertensive, which obviously indicates a worsening condition. For hypertension, the increase and prolonged pressure can, and usually does, damage arterial walls, which result in growths that inhibit blood flow. These growths (atheromas) weaken the heart and make the patient highly susceptible to myocardial infarction, or heart attack. Stage 2 simply means this condition is acute and the patient is in dire need of medical attention. Hypotension is the opposite and isn't an overly serious condition, causing dizzy spells and, in some cases, fainting and shock.