Pressure

Hypertension is a common and, at least initially, symptom free disease. Lay people say they have high blood pressure or "a touch of pressure". Inexpensive home blood pressure monitors have become widely used. I hate these monitors. A seemingly universal misconception is that high blood pressure is the equivalent of the psychological feeling of being pressured. Work, family or money stressors lead my soon-to-be patients to check their BP. An elevated reading sends them to the ER in a panic.

Hypertension is a complex disease. Genetic, dietary and anatomic factors may all contribute to the development of HTN. There are no symptoms of early HTN. Patients relate elevated BP with headaches, nose bleeds and anxiety. This is a false correlation. The blood pressure measurement taken from the arm is not the level in the entire body. The arteries that supply the brain have the ability to autoregulate. The BP in the brain is not the same as in the arm.
Headaches may be symptomatic of advanced and prolonged HTN. The nose is not a blow out valve. If your nose is bleeding it is not because your BP is elevated.

The measurement of blood pressure is most accurately obtained with a blood pressure cuff, stethoscope and a well trained ear. The cuff is inflated to a pressure that must be above the patient's systolic pressure. The 120/80 is the reading of the systolic/diastolic pressure in the arteries. Systole is the active contracting phase of the ventricles of the heart. The left ventricle pumps blood into the aorta and subsequently to all the arteries, arterioles and capillaries in the body. The lower number, diastolic pressure, is the reading during the filling phase of the ventricle.

Arteries have three layers that allow them to expand and contract. Aging leads to a decreased elasticity of the arterial wall. Hardening of the arteries is the commonly used term for this decreased flexibility. Aging, increased weight, high salt intake, lack of exercise and stress may all lead to increased blood pressure.

Blood pressure readings are related to the auscultation of the Korotkoff sounds. After pumping up the blood pressure cuff, it is slowly deflated. One listens with a stethoscope over the brachial artery and notes the reading when a "pulse" is heard. The first Korotkoff sound is the systolic blood pressure. As the cuff continues to be slowly deflated, the reading when the sound stops (some use the reading when the sound is muffled) is recorded as the diastolic pressure. This takes some skill. Using too much force, with the stethoscope, over the artery can effect the reading. If the Korotkoff sounds are heard with the cuff inflated it means that the initial cuff pressure was lower than the patient's systolic BP. It is necessary to totally deflate the cuff, wait a few minutes and inflate the cuff to a higher initial pressure.

Electronic BP monitors tend to read higher than BP's done by hand. Like all measuring devices, BP monitors need to be regularly calibrated. The size of the cuff used is also important. A health care worker will use the correct sized cuff for the diameter of the patient's arm. A too small cuff will give a falsely higher reading. The one-size-fits-all BP monitors are often too small for our rapidly "expanding" patient population.

One of my partners treated a patient who's presenting complaint was that he couldn't find a primary care physician (PCP). The patient has HTN and had been started on meds during a prior ER visit. His prescriptions had run out. The ER as primary care center is an issue the continues to grow in importance. When a patient checks their BP and gets a high reading they rush and call their PCP. The advice is usually to go to the ER for further evaluation.

HTN was once referred to as the silent killer. Because HTN causes no symptoms, the initial presentation could be when the end organ damage has occurred. Prolonged untreated HTN strains the heart. The left ventricle compensates for elevated systolic BP by getting thicker. Hypertrophy of the muscle of the left ventricle will eventually lead to heart failure or heart attack. The brain's autoregulatory ability will, over time, fail and stroke will be the result. The kidneys are involved in blood pressure regulation. These vitals organs will also be damaged by long standing HTN.

I know that this will sound familiar but here goes: Maintain a healthy weight. Exercise regularly. Limit your salt intake. See your PCP for regular check ups. Take your blood pressure meds as prescribed. HTN is a chronic but manageable disease. Do not stop taking your BP meds without getting your doctor's OK. Normal BP for an adult is based on recommendations from the American Heart Association. Visit their website for current advisories.