When the bed bugs bite
Helen Foster
Each night we sleep with two million mites, change position every 12 minutes and lose half a litre of fluid. We are exhausted. What should we do ?

HEALTH BULLETIN
The ways of nuclear medicine

Q&A
More about kidney transplants
Answers by Major-General (Dr) Jaswant Singh.

Are your eyes ageing? Take care
THE following are the conclusions drawn by Dr Rajeev Gupta, a senior lecturer in the Department of Ophthalmology, at the GMCH, Chandigarh, on the problems discussed by him on age-related macular degeneration (published last week.)

High blood pressure: the silent killer
Dr G.S. Grewal

HIGH BLOOD pressure or hypertension is called a "silent killer" because in most cases there are no clear warning signs even as the condition damages our health. Hypertension is a common clinical problem with grave implications for public health. Complications of untreated hypertension include heart enlargement, heart failure, stroke, kidney failure and athersclerotic heart disease.

Systemic HTN defined as SBP>140mmHg or DBP>.90mmHg, affects 50 million adult Americans. About 90 to 95% of hypertensive patients have HTN which is "essential". It implies that a definite cause cannot be identified. The remaining 5 to 10% have secondary hypertension in which a specific cause can be identified. While many causes of high blood pressure are unknown, the risk factors are well known. They are a combination of things you can't control and things you can.

The sixth Report of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure has classified the follow-up of blood pressure in adults based on the initial reading.

Pathophysiology (How high blood pressure is caused)

In most of the cases the cause is not known but regardless of the cause HTN is related to increased TPR (total peripheral resistance). Only infrequently is HTN caused by the increased cardiac output alone. The secretion of an enzyme called renin from the kidneys causing subsequent release of another enzyme called angiotension I and II from the liver, which causes vasoconstriction and hence the release of aldosterone, causing salt and water retention causing increased intravascular volume, has been identified. However 60% of the essential HTN cases have normal plasma renin levels. Sodium: Clinical studies and epidemiologic observations strongly support a link between high blood pressure and the dietary sodium intake. Persons especially sensitive to sodium intake are blacks, older people and those with higher levels of blood pressure.

Potassium deficiency may increase the blood pressure and can also cause extra beats in heart. A high dietary potassium intake improves blood pressure control and approximately 90mmol/d is recommended

Calcium deficiency is associated with the development of high blood pressure and may amplify the effects of high sodium intake. The overall effect of increasing calcium intake is minimal and currently no recommendation to increase the daily intake in excess of the current recommended daily allowance of 800-1200 mg exists.

Magnesium: No firm data is available.

The neurogenic factor is likely to be a major contributor to the pathogenesis of high blood pressure among young people.

Endocrine hypertension is mainly through adrenal hormones by salt and water retention acting both in form volume of expansion and vaso-constriction.

The Renal Parenchymal Disease often contributes to high blood pressure by causing salt and water retention and activation of the RAA system.

Clinical manifestations

History and symptoms: The majority of the patients are asymptomatic and symptoms of severe blood pressure include fatigue, headache, blurred vision, early morning occipetal headache, and in some cases angina pectoris due to the increased myocardial oxygen demand.

Essential hypertension: A strong family history of high blood pressure suggests that it is essential hypertension.

Secondary hypertension clues suggest a secondary cause of high blood pressure.

The level of BP>180/110mmHg.

The onset of blood pressure before 25 years of age or after 55 years.

A poor response or failure to respond to adequate medical therapy.

"Paroxysmal headache, sweating and or palpitation while having high blood pressure.

*High blood pressure associated with low potassium levels.

Drugs: Mainly there are oral contraceptives, non steroidal anti inflammatory agents, corticosteroids, nasal decongestants, appetite suppressants, cyclosporin, erythropoietin, tricyclic antidepressants etc.

A detailed history of alcohol intake is necessary. The intake of more than two ounces of ethanol per day can raise the blood pressure and cause resistance to anti-hypertensive therapy.

Obesity predisposes one to high blood pressure by its association with hyperinsulinaemia and the increased intravascular volume.

The physical examination should focus on blood pressure measurement and the evidence of any target-organ damage — clues to any secondary cause.

Blood pressure measurement

"It should be determined with a calibrated sphygomanometer, an instrument with a mercury column, after 5 minutes of rest and more than 30 minutes after smoking or ingestion of caffeine.

The rubber bladder of the instrument should encircle at least 80% of the bared upper arm. A cuff that is too small produces falsely elevated blood pressure.

A cuff that is too large or loosely applied will result in a reading that is falsely low.

The patient should be seated with the arm horizontal at the heart level. The positioning of the arm vertically in a dependent position results in an elevated BP-reading due to changes in the hydrostatic pressure.

Palpation is used initially to estimate systolic BP. The cuff is rapidly inflated till the radial pulse is extinguished.

The cuff is then slowly deflated and the point at which the radial pulse becomes palpable is systolic BP.

Auscultation is then used to determine the SBP and diastolic BP. The cuff is inflated to approximately 20mmHg above the palpated SBP.

While listening with the stethoscope over the brachial artery, the highest level at which the sound is heard is SBP, and the point at which there is complete disappearance of sound is DBP.

Initially, elevated readings should be confirmed on at least two subsequent visits and the results should be averaged.

BP should be measured in the opposite arm as well. If there is not an equal reading, a higher measurement should be considered as the patient's BP.

The evidence of target organ involvement.

A fundoscopic examination should be done by a qualified doctor.

A cardiac examination, i.e the examination of the heart should be done to see any evidence of a heart enlargement.

All other signs of anaemia, weakness (general or localised) should be looked for any evidence such as kidney failure.

The diagnosis
All hypertensives must go through diagnostic tests used to determine any target organ damage and co-existing cardiac risk factors.

Urinanalysis and Serum BUN and creatinine should be done to evaluate the kidney function. An ECG should be done to identify heart enlargement. Some advocate echocardiography and chest X-rays as well.

The determination of risk factors for heart such as total HDL, LDL, cholestrol, triglycerides and the fasting glucose level is necessary. Other factors to be seen are serum potassium, calcium, and uric acid.

A general approach to therapy

The goal of the therapy is to maintain blood pressure below 140/90 mm Hg, and thereby decrease the chances of the related kidney failure, stroke and heart failure.

In essential hypertension the total therapy involves lifestyle modification alone or in combination with drug therapy, depending on the level of blood pressure and the evidence of vascular disease and target organ damage.

Secondary hypertension: The goal of the therapy of secondary hypertension is to identify and correct the underlying cause.

The doctor in charge should involve the patient in treatment decisions and provide positive reinforcement and education about blood pressure because these measures may improve long-term compliance.

Life-style modification should be considered first for all patients. These measures may occasionally lead to the control of blood pressure, especially when DBP is less than 100 mm Hg, or may reduce the number and dosage of the medication required to manage blood pressure. But the implementation of life-style modifications should not delay the start of the appropriate drug therapy — especially for those at higher risk.

Weight reduction

Weight should be maintained within 15% of the ideal body weight.

In the patients who have more than 110% to 160% of the ideal body weight, the evidence suggests that the weight loss of >4.5 kg is required to a significantly lower BP.

Overweight persons with excessive fat in the upper portion of the body are especially at risk for cardiovascular mortality.

The alcohol intake can raise BP and cause resistance to antihypertensive therapy. Alcohol consumption should be limited to no more than one ounce per day of ethanol equivalent to two ounces (60ml) of 100 proof whisky, 10 ounces 300ml of wine and 24 ounces (720ml) of beer.

Sodium restriction: Sodium may maintain elevated BP and/or interfere with the action of antihypertensive medication. Moderate sodium restriction of limiting the daily sodium intake to less than 100 mmol<2.3 gms of sodium or 6 gm of salt). Although sodium restriction may not lead to decreased BP in all patients, an effort at sodium restriction should be attempted.

Exercise: Regular aerobic exercise is beneficial in reducing BP and the risk of future cardiovascular disease.

Smoking: Tobacco's use is associated with an increased incidence of malignant hypertension as well as the relative resistance to antihypertensive drug therapy. Tobacco may cause acute hypertension also.

Diet: A low-fat, low-cholestrol diet should be given to overweight patients and to those with high cholestrol levels. A diet rich in fruits, vegetables, and low-fat dairy foods and with reduced saturated and total fats may significantly lower the BP level.

Drug therapy is indicated for the treatment of mild blood pressure when 3 to 6 months of life-style modification do not result in adequate BP control.

In moderate to severe hypertension or in the presence of target organ damage, drug therapy is required in addition to life-style modification.

Initial monotherapy is recommended but it is always important to get in touch with your family physician to decide the drug group, and the dosage required to control your BP.

Dr G.S. Grewal, MD, is a noted physician and the Medical Director of the SASGM Mediscan Hospital, Ludhiana.

When the bed bugs bite
Helen Foster

Each night we sleep with two million mites, change position every 12 minutes and lose half a litre of fluid. We are exhausted. What should we do ?

As day becomes night, darkness triggers the changes in the body that prepare us for sleep — relaxing hormones take over from stress ones, your temperature drops and your whole system slows down. But be warned — once you’re asleep, changes carry on occurring that make your body behave differently and it’s best to know what you’re dealing with.

Your skin

Night time is prime regenerative time for your skin — particularly between the hours of 2am and 3am. Studies by cosmetic companies have shown that this is when the skin is abuzz with surges of growth hormone and other substances that lead to the formation of collagen and the repair of some of the DNA damage that occurs every day through exposure to UV rays. The skin is also more porous at this time, which means that any skincare on the face or body is likely to be more effective at getting to the lower levels of skin where it’s actually needed.

Dermatologist Nicholas Lowe, from London’s Cranley Clinic, has speculated that this increased permeability may be due to the amount we sweat while we sleep. On average, we lose about half a litre of fluid from our body each night. This dehydrates the skin, and when skin is dry it will try and draw moisture from the air, sucking in anything else it finds on the way. And you’d better hope it does find something or you’re increasing your chance of wrinkles.

On an average, we change position every 12 minutes while we sleep, and that movement causes the skin on the face to crease. “If the skin is dehydrated, that creasing won’t bounce back and you’ll actually create a permanent line in the skin,” says New Orleans-based dermatologist Prof Mary Lupo. “This is why people who sleep on their front are always more wrinkled than those who sleep on their back.” Lupo, therefore, advises sleeping face up, if you can, or at least using a satin pillowcase which allows you to slip and slide across the surface and cut crease potential. Of course, it’s still important to keep the skin hydrated, so moisturise well before bed with a product you know you’re not allergic to — your immune system is more active at night, making allergic reactions more likely.

The lungs

Breathing slows at night and the muscles of the chest relax. Still, if you’re asthmatic, you are more than 100 times more likely to have an attack at 4am than any other point in the day. The main culprit is the lowered levels of adrenaline while we sleep. “Adrenaline is the fight or flight hormone,” says Dr Jim Waterhouse, from the Institute of Sport and Exercise at Liverpool John Moores University. “It prepares us to move fast during times of stress and attack and it’s present in our body the whole time we are awake. One of its jobs is to keep the airways of the respiratory system wide open so, should we need to run, we are able to breathe faster.” To help us sleep, however, adrenaline levels have to fall and as this happens the airways constrict, becoming their smallest at around 4am, which in an asthma sufferer can be enough to bring on an attack — especially as the airways are likely to be irritated anyway. Night time brings us into contact with one of the most common triggers for asthma: the house dust mite. Ten per cent of us are allergic to their droppings, and the average bed can contain 2m mites producing around 20 droppings each an hour. And the mites (and the droppings) don’t just stay in the bed. “While you sleep you probably have around 1,000 mites running around your eyelids,” says Waterhouse. The good news is dust mites can die. Switching to foam pillows and spraying with anti-mite sprays can help. Also invest in a dehumidifier (from major electrical stores). Mites can’t survive in humidity of less than 50 per cent. If you do try everything and are still having trouble, ask your doctor about time-release inhalers (Uniphyllin Continus is the most commonly used here). These ensure that the active ingredient (something called theophylline, which keeps the airways open) actually reaches its peak around 4 am.

The metabolism

The metabolism is the speed at which we burn calories, and it slows down at night. Obviously this is partly because you’re not moving around, but there is more to it than that. “Sleep slows the speed at which you carry out bodily processes that burn energy “(like breathing)”, says Professor Horne. “The result of this is that you expend about 10 per cent fewer calories when you’re lying asleep than you would lying in exactly the same position when you’re awake.” Weight watchers might like to know that this nightly calorie deficit can be offset by weight training. The more muscle you have in the body, the more calories you burn even if you’re sitting still — one study published in the American Journal of Clinical Nutrition found that regular weight training boosts your basal metabolic rate (the calories you burn sitting still) by 15 per cent — 5 per cent more than that night-timedrop. For best results, work out three to five times a week on all your major muscle groups, choosing a weight on which you can do no more than three sets of eight to 12 repetitions.

The circulatory system

According to major US research, you have a 70 per cent greater chance of having a heart attack or stroke between 7am and 9am than at any other point in the day. “The reason for this is the circulatory changes that occur in your body at night. “The main one of these is that blood pressure drops, because we’re lying down and the heart has to work less hard to pump blood around the body,” says Professor Horne. Now while low blood pressure is generally a good thing, it does also mean that if you wake up and suddenly jump out of bed, the heart and circulatory system have to work harder to get things moving. “And if there is a weakness in the heart, this can sometimes be too much of a shock for it.” Do your heart a favour, and sit up and relax for 10 minutes to allow your body to get used to sending blood upwards for a while.

To be concluded

HEALTH BULLETIN

The ways of nuclear medicine

In general, the basic procedure involves 5 steps.

1. The patient receives radioactive material (an isotope)

in one of several ways:
* injection or IV

* capsules

* liquid

* special tubing

* inhalation.

2. The isotope travels to target organs and tissues

-- different isotopes are matched with different compounds that go to specific organs and tissues.

3. The isotope gives off gamma rays

-- a form of radiation that can only be seen with special equipment. 
4. Special equipment provides images and readings of target organs and tissues. This equipment does not give off any radiation. 
5. The images and readings are studied by a nuclear medicine physician and the patient's health-care provider.

Thyroid uptake
Thyroid uptake and scan give important information about the thyroid (a gland in the neck). These procedures are generally done over a two-day period.

Before these procedures:

* You may be asked to avoid food and water (starting the night before day 1).

* You also may need to avoid certain foods or medications in the weeks before the test.

On day 1:

* You’ll receive the isotope, usually by mouth (liquid or capsule). You may be asked to avoid eating or drinking for 1-2 hours afterwards.

On day 2:

About 24 hours after receiving the isotope, you’ll sit or lie down for:

* the uptake -- a probe is passed over your neck to measure your thyroid's ability to absorb the isotope. This takes about 15 minutes.

* the scan -- a gamma camera takes pictures to show your thyroid's condition and ability to function. This takes about 45 minutes.

NOTE: You may need just one of these procedures done. You may also need one or both done on day 1, about 4-6 hours after receiving the isotope.

If you need a scan only (no uptake), you’ll usually receive the isotope by injection.

Working towards perfect health

1. Stop smoking and drinking.

2. Start the day with a glass of warm water and a dash of lime.

3. Take a brisk, 20-minute walk each morning.

4. Include one green vegetable in every meal.

5. Drink six to eight glasses of water a day.

6. Steam or boil vegetables (don't fry or saute).

7. Use salt in moderation.

8. Read a great book at least once a week.

9. Eat just to the point of fullness.

10. Learn to relax. Spend 20 minutes consciously relaxing each muscle of your body.

11. Learn he healing power of laughter. Watch a crazy movie, read a funny book, laugh aloud.

12. Get a good night's sleep, every night.

— Courtesy: ICI India Ltd

Things to do when fever strikes

When infection strikes, the body reacts with an inflammatory response in an effort to contain and overcome it. Fever is a part of this response and protective and useful in nature. It should not, therefore, be interfered with unless there are reasons to do so, for example, the extreme discomfort of the patient, or danger of it entering the zone of hyperpyrexia.

Fever is usually accompanied by headache, malaise, bodyache and general weakness. Other symptoms like nasal discharge, pain in the throat, cough, urinary symptoms or disturbances of consciousness, and others, may vary according to the system involved in the pathological process. Remember that fever is not a disease entity but an outward manifestation of many diverse diseases like those which have been already discussed. It is the doctor who will diagnose the cause and treat accordingly. Your role is to help him by keeping a proper record of temperature and development of symptoms, giving medication as ordered, and keeping a watch on the patient. In case you are confronted with acute fever, you should know what you need to do.

Dr G. D. Thapar and Dr Anil Thapar in “Pain and Fever”

Q&A
More about kidney transplants

Are your eyes ageing? Take care

THE following are the conclusions drawn by Dr Rajeev Gupta, a senior lecturer in the Department of Ophthalmology, at the GMCH, Chandigarh, on the problems discussed by him on age-related macular degeneration (published last week.)

AMD: This is a non-hereditary, degenerative disorder affecting the central part of the retina (macula). It is the most common cause of permanent central visual loss in the elderly and accounts for nearly 10% of the "legal blindness". Apart from age, the other risk factors include cigarette-smoking and hypertension. Though at present there is no effective medical or surgical treatment to prevent this syndrome, certain serious vision-threatening complications can be treated with laser treatment.

Miscellaneous conditions: Corneal opacity, myopia, retinal detachment and uncorrected refractive errors can also affect vision in the elderly. Voluntary eye donation should be encouraged to restore the vision lost due to corneal blindness.

Recommended screening strategies: We must ensure that no citizen becomes blind due to preventable causes and that the best possible vision is restored to the curable blind. The suggested guidelines are:

(1) Persons above 50 years should get a complete baseline eye examination done by an eye-specialist.

(2) A prompt opinion should be sought from an ophthalmologist in the case of any visual symptom, change in glasses, coloured haloes, blurring of the vision, multiple images etc.

(3) All patients having diabetes, glaucoma and AMD should be on a strict follow-up schedule as advised by the ophthalmologist. Unattended, these conditions may lead to irreversible blindness.