Dr Kumar's BASIC HEALTHCARE FOR ALL
Blood pressure is quite simply explained as the lateral pressure exerted by blood on the walls of vessels in which it is contained and flows through. Of the two blood vessel systems, arterial (thick-walled) & venous (much thinner), the pressure measures far more in arteries than in veins. High blood pressure (hypertension) occurs when excessive force is exerted against the arterial walls as the heart pumps blood (systole). This dreaded 'silent disease' has no obvious symptoms until it has reached an advanced and dangerous state, at which point, it may cause headache, lightheadedness, ringing in the ears, and possibly rapid heartbeat (tachycardia). If it remains uncontrolled (and undetected), it may well lead to a heart attack, stroke, eye damage, or even renal failure over a period of time.
The modern (digital) and the olden mercury column type (sphygmomanometer) blood pressure measuring instrument. The digital instrument is a very useful gadget to monitor BP quite easily at home or during our travels outside. It keeps operating for quite sometime on just 4 pencil cells. These digital machines are totally automatic, one just has to wrap the inflatable cuff around the upper arm. Readings are readily available for systolic, diastolic pressure vales, as also for the pulse rate.
In most people, the cause of hypertension is not known, and it may be classified as primary or essential. In about 5-7% of the cases, it may result from underlying renal disease, some hormonal imbalance, or some other identifiable organic factor. This then is known as secondary hypertension. Predisposing risk factors have been identified as (i) obesity, (ii) a family history of hypertension, or even a cerebral stroke at an early age. Allegedly, a high-salt diet is surely a causative reason for hypertension in genetically predisposed persons. Epidemiologically, African-Americans show a higher incidence of hypertension than whites. Women are supposedly less prone to high blood pressure than men, but, at the same, pregnancy and use of oral contraceptives may increase their susceptibility as well. The disease affects an estimated 55 million Americans of all age groups - young and old.
Because there usually are no symptoms, hypertension is most often diagnosed during a routine medical examination or a special screening programme. BP is normally measure with an instrument called as sphygmomanometer. We're not going to discuss the details of this clinical instrument, nor of the BP-measuring procedure using this equipment at this web site. Quite a few physicians and clinics/hospitals still use this instrument, but, for home-monitoring purposes, this rather bulky and tedious-to-use equipment has been replaced with a far easier 'digital' apparatus, which one can regularly use all by oneself.
Normal blood pressure values for healthy
adults are 120 (systolic, when the heart is contracting) / 80 (diastolic,
when the heart is refilling). Usually this difference between the upper &
lower value is called as 'pulse pressure'. It is always (120 minus
80) that is 40 or more. Reducing 'pulse pressure' may indicate
serious issues with one's circulatory health, and may cause functional
heart failure, or may even prove fatal if it intensifies suddenly. Over a
period of 24 hours, blood pressure values may vary considerably. It is
usually lowest during sleep and highest during early morning, mostly owing
to epinephrine surge in the morning. Anger, stress, anxiety or stimulation
(caffeine, nicotine, alcohol) make BP shoot a bit. As said earlier, a
resting BP value of 120/80 or near about is considered normal for adults,
and a consistent reading of 140/90 or higher over a period of time is
classified as clinical hypertension. However, to make a right diagnosis,
BP must be measured a number of times over several weeks, unless the
initial reading itself is dangerously high, e.g., 160/100 or higher.
Wearing of a an ambulatory 24-hour BP monitor may be recommended in some
cases. This device continually measures and records blood pressure.
Besides all these clinical procedures, if any complication related to
hypertension, such as a hypertrophied heart or kidney damage is suspected,
additional, standard cardiology tests may be required for a reasonable
clinical evaluation of the patient.
The choice of treatment is determined by the severity of the hypertensive state of an individual, accompanied possibly by some related complications. Mild to moderate hypertension, generally defined as readings 140-150/90-105, is initially treated by lifestyle changes. Anti-hypertensive drugs are prescribed when lifestyle changes fail to achieve the desired lowering or when blood pressure is diagnosed in the moderate to severe range of more than 160/105. Although high BP almost always can be controlled with medication, there is just no single antihypertensive drug that works for everyone. Treatment may involve taking just one or several medications. The major classes of these antihypertensive drugs are as follows > Diuretics (water pills) that cause excessive urination; Beta-blockers that slow down the heart rate and force of myocardial contraction; Alpha-blockers that work through the autonomic nervous system and widen the arteries; ACE (for angiotensin converting enzyme) inhibitors that lower BP by blocking the synthesis of a potent vasoconstrictor called angiotensin II, that narrows blood vessels, thereby raising blood pressure; Calcium-channel blockers work by dilating the blood vessels, thus making BP fall; Vasodilators, which act directly upon blood vessels and widen them to lower raised BP; Peripheral adrenergic antagonists, these block the release of norepinephrine, a hormone that raises BP; Centrally acting drugs, lower blood pressure by reducing nerve impulses from the brain; Anti-anxiety & tranquilising drugs are often used to make the patient more restful during a sudden spurt in BP, but are usually avoided, as this class of drugs may in fact be habit-forming.
Side effects are quite often a problem with these antihypertensive drugs. However, they can almost always be minimized by changing eithyer the dosage or the prescribed medication itself. Dizziness, anxiety, palpitation, insomnia, impotence and depression can be the major side effects. Some of these may sure subside as the body gets used to the drug. Also, one always have to choose the lesser evil when afflicted with a potentially fatal ailment.
1. Do keep taking your prescribed BP drugs routinely. There may be minor variations in diurnal BP readings, but any major and sudden fluctuations MUST be reported to your physician. It is important to home-monitor your BP routinely, at least twice-a-week, PLUS whenever you aren't feeling well. At regular intervals, your BP instrument must be calibrated/standardized with that of your physician's, especially so if you have bought a new apparatus. Do carry your instrument with you whenever you are traveling. Most BP patients surprisingly ignore home-monitoring their BP, and they also don't get it checked at the clinic. Merely taking the prescribed medication isn't enough ... the BP must ALWAYS remain well-controlled. All medicines have side-effects, and there is absolutely no point in ingesting so much of toxic chemicals into your body and yet have your BP not controlled well enough.
2. Even if your doctor has not advised, all hypertensive people above the age of 45 years must have a general medical check-up. And, those over 60 years, must have a detailed medical check-up at least once a year, if not twice (preferably), especially if one is suffering both from hypertension & diabetes mellitus. This regular check-up MUST include eye examination by an ophthalmologist.
3. Points listed at 1 & 2 above won't be of any use at all if you don't undertake a definite lifestyle modification that is required for your own well-being. Diet, weight and activity (mild exercise) CONTROL must always looked into.
4. A program of aerobic exercise designed to improve overall cardiovascular fitness can help to manage BP better than an entirely sedentary lifestyle. However, before embarking on any exercise regimen your body isn't already used to, it may be advisable to have an exercise stress test done.
5. Mild to moderate hypertension can often be controlled through a combination of dietary changes and mild exercise alone. Add minimal salt to your food. And, do realize that salt sodium isn't just the table/kitchen salt, but is present is quite a few preserved food items as well, including the popular breakfast cereals. It is often recommended to increase your consumption of fruits & vegetable and whole-grain products, while reducing consumption of red meat and other fatty vegetarian or non-vegetarian items, as also to minimize or totally avoid the use of saturated fats in our kitchens.
6. If you do smoke, stop right now. Also, as far as possible, avoid exposure to passive smoke. Minimize alcoholic beverages.
As your hypertensive state becomes chronic, and especially if your BP doesn't remain well-controlled, your heart, blood vessels, kidneys, eye and brain are also affected to varying extents. It will be especially so if you suffer both from BP and diabetes. Decreased renal function and eventual renal failure may ensure. Your vision may be affected 'coz of retinopathy. The heart becomes hypertrophied, especially the left ventricle (that pumps the blood out), heart failure may ensue sooner or later. Worsening state of your blood vessels usually lead to atherosclerosis (narrowing of arteries 'coz of cholesterol deposition) and arteriosclerosis (hardening of arteries 'coz of age). Thrombosis (intravascular blood clots) is a problem that faces all BP patients squarely in the face. If it happens in coronary arteries, it leads to a heart attack (myocardial infarction), in brain it leads to a stroke that causes varying degree of paralysis. There may even be minor or major haemorrhages in eye and brain - some of these states may may sure prove fatal. Because of excessive drug ingestion by us, our liver and kidney are a lot strained functionally as well, and may eventually get partially or totally damaged. Hope all these issues frighten one enough to kickstart a reasonable good healthcare programme of keeping your BP well under check ALWAYS.
OTHER CAUSES OF BLOOD PRESSURE
An adrenal tumor called a pheochromocytoma produces an adrenaline-like hormones than can cause very high blood pressure. A narrowing of the renal artery to the kidney can also raise blood pressure to various extents, as can pre-eclampsia, or toxemia of pregnancy - a serious complication that may sometimes develop during the final trimester. Another hypertensive crisis can be pulmonary arterial hypertension (PAH), quite different aetiology from that of regular hypertension described above. It implies high blood pressure in the arteries that supply blood to lungs from the heart. In such a scenario the tiny pulmonary arteries become narrow or get totally blocked, making it that much harder for blood to flow through them, and thus indirectly making the heart work harder to pump blood through the tiny arteries so affected. This may have serious consequences, as after a while the myocardial muscle lose strength, get weaker, leading eventually to heart failure.
Vascular degeneration with chronic hypertension may result in the localized weakening of the walls blood vessels. An aneurysm is a bulging in the wall of a weakened segment of a blood vessel. The aorta, the body's largest artery, is most often affected, although aneurysms also develop in the arteries at the base brain or in some small vessel within the brain itself. Aneurysms usually do not produce any symptoms until they are large enough to press on adjoining tissues/organs. For example, an aortic aneurysm that occurs near the heart can cause chest pain and other symptoms that may mimic angina or even a heart attack. In this type of aneurysm, the artery's inner & outer walls may divide, allowing blood to seep in between the layers and reducing blood flow in other parts of the body. This is called a dissecting aortic aneurysm and is considered especially dangerous, An abdominal aneurysm can sometimes be felt as throbbing, tender mass just under the skin, below the rib cage in the center of the abdomen. If it leaks, it can cause pain that radiates to the back and groin. In a carotid aneurysm, the throbbing is felt in the neck, and there may also be a visible bulging under the skin. Arteriosclerosis, a hardening of the arteries, promotes aneurysms, as does chronically elevated blood pressure (hypertension). Other causes may be congenital defects and inherited disorders. As an aneurysm enlarges, the danger increases that it might suddenly rupture. A burst aneurysm is usually fatal within minutes, especially if the aorta or carotid arteries are involved, although immediate surgery to arrest bleeding and repair the break at times proves life-saving.