High Blood Pressure (Hypertension)

Transcription

1 High Blood Pressure (Hypertension) Information for patients Coronary Care Unit Phone no: Ref: Review: 08/2015

2 What is Blood Pressure? Blood pressure measures how strongly blood presses against the walls of your arteries (large blood vessels) as it is pumped around your body by your heart. If this pressure is too high it puts a strain on your arteries and your heart, which makes it more likely that you will suffer a heart attack, a stroke or kidney disease. Blood pressure is measured in millimetres of mercury (mmhg) and it is recorded as two figures: systolic pressure: the pressure of the blood when your heart beats to pump blood out diastolic pressure: the pressure of the blood when your heart rests in between beats An example of this could be the blood pressure is 120 over 80, which is written 120/80. The first figure is the systolic blood pressure the pressure in the arteries when the heart contracts and pushes the blood out into the body. The second figure is the diastolic blood pressure. This is the pressure in the arteries when the heart is filled with blood as it relaxes between two beats. What is hypertension? There is a natural tendency for blood pressure to rise with age due to the reduced elasticity of the arterial system. The definition of hypertension is thus dependent on the age of the patient. For example, in a 60-year-old patient, hypertension occurs when the blood pressure is higher than 160/90 while the patient is at rest. However, in patients who have diabetes, a blood pressure higher than 130/80 would be considered high. Even though hypertension itself rarely has any symptoms, it can cause many serious problems. What causes hypertension? In more than 90 per cent of cases, the cause is unknown. This is called 'primary' or 'essential hypertension'. In the remaining minority of cases, there is an underlying cause. This is called 'secondary hypertension'.

3 Some of the main causes for secondary hypertension are chronic kidney diseases, diseases in the arteries supplying the kidneys, chronic alcohol abuse, hormonal disturbances and endocrine tumours. How is blood pressure measured? To take a blood pressure measurement, a blood pressure cuff is placed around the upper part of the arm. The cuff is inflated and the doctor listens to the artery just below the cuff as the air is then released. When the doctor can hear the heart beat, he or she will note the systolic pressure. When the sound disappears, the doctor will record the diastolic pressure. Blood pressure can be measured in other ways, such as using an automatic blood pressure gauge, which can also be used at home. When the doctor measures blood pressure, it sometimes increases slightly because the patient is nervous. This reaction is called 'white coat hypertension' and the doctor will usually perform several blood pressure readings to get a better idea of what your average level tends to be. Blood pressure can also be measured evenly over the course of a day using an automatic day and night pressure gauge, which the patient carries for 24 hours. What are the symptoms? Hypertension hardly ever causes symptoms and may not be noticed at all. However, serious and rare manifestations of severe hypertension can be: headache, sleepiness, confusion or coma serious breathing difficulties nosebleeds. What factors increase the risk of hypertension? Anyone can suffer from hypertension but certain factors can seriously aggravate hypertension and increase the risk of complications: a tendency in the family to suffer hypertension

4 obesity smoking diabetes Type 1 or Type 2 kidney diseases high alcohol intake excessive salt intake lack of exercise Certain medicines, such as steroids and certain kinds of diet pills. What can I do? Have regular blood pressure tests if there is a family tendency for hypertension. In this way, treatment can be started before any complications arise. Change your lifestyle: o Stop smoking, o lose weight o exercise regularly. o Cut down on alcohol o eat a varied diet, o Try to avoid stressful situations, o and experiment with different relaxation techniques. If you suffer from hypertension, your blood pressure should be measured regularly so that any necessary treatment can be arranged. If your blood pressure requires medical treatment, you will probably have to take medicine on a regular basis. If so, never stop taking it without consulting your GP, even if you feel fine. Hypertension can lead to serious complications if left untreated.

5 What can your doctor do? Pinpoint risk factors and help change your lifestyle in order to reduce blood pressure. If necessary, offer medication for the reduction of blood pressure and arrange regular monitoring. Possible complications atherosclerosis (narrowing of the arteries) strokes (CVAs) - cerebral haemorrhage or cerebral thrombosis thoracic aortic aneurysm - expansion of the main artery in the chest abdominal aortic aneurysms - expansion of the main artery in the abdomen heart attack heart failure (reduced pumping ability) kidney failure eye damage. Probable developments By treating the hypertension, complications can be avoided and average life expectancy will remain almost normal. Without treatment, life expectancy may well be reduced due to the risk of developing any number of the complications listed above. What medicines are used? Diuretics help the body excrete superfluous fluids and salt through the kidneys and, in certain cases, relax blood vessels thus reducing the strain on the circulation. Diuretics can have different effects on your kidneys and can be divided into thiazides, loop diuretics, potassium-sparing diuretics or a combination of these.

6 Beta-blockers block the effect of the hormone adrenaline and the sympathetic nervous system on the body. This relaxes the heart so that it beats more slowly, lowering the blood pressure. Alpha-blockers cause the blood vessels to relax and widen. Combining them with beta-blockers has a greater effect on the resistance in the circulation. Calcium-channel blockers reduce the muscle tension in the arteries, expanding them and creating more room for the blood flow. In addition, they slightly relax the heart muscle so that it beats more slowly, thus reducing the blood pressure. ACE inhibitors interrupt the formation of a hormone (called angiotensin II) that makes the blood vessels contract. As a result, the vessels expand. The tension in the circulation is also lowered by more fluid being filtered from the vessels into the urine by the kidneys. Both mechanisms help reduce blood pressure. These are very useful medicines for the treatment of high blood pressure and, if your blood pressure is not easily controlled on simple medication, your doctor will probably use a medicine of this type. The following medicines are used less frequently: Indapamide is a mildly diuretic preparation which also relaxes the peripheral arteries. Hydralazine relaxes the vascular walls in the peripheral arteries thereby reducing the blood pressure. Methyldopa stimulates the alpha receptors in the brain that relax the blood vessels, causing the blood pressure to drop. Moxonidine is another medicine that acts on receptors in the involuntary part of the brain, causing blood pressure to decrease. Minoxidil relaxes the small arteries so that blood pressure drops. It must be used in combination with other antihypertensive medicines.

7 References: NHS Choices Comments, compliments or complaints We welcome any suggestions you have about the quality of our care and our services. Contact us: Freephone: Phone: Textphone: Customer Care, Reception, Macclesfield District General Hospital, Victoria Road, SK10 3BL For large print, audio, Braille version or translation contact Communications and Engagement on Admission information The trust accepts no responsibility for the loss of, or damage to, personal property of any kind, in whatever way the loss or damage may occur, unless deposited for safe custody. Please leave valuables at home. If you need to bring personal items that are expensive, for example micro hearing aids, please be aware that you do so at your own risk East Cheshire NHS Trust is committed to ensuring that patients and staff will always be treated with dignity and respect. There will be no age, disability, gender, race, sexual orientation or religious discrimination NHS Direct (part of NHS Choices) is a 24 hr phone advice service providing confidential health advice and information. Phone: (Textphone )