Postural hypertension
Some people experience sudden drop in blood pressure when they stand up from lying or sitting position. This type of low blood pressure is called postural hypertension.
Postural hypertension is a condition when autonomic nervous system (part of nervous system which controls such vitally important involuntary processes as heartbeat) is unable to respond adequately to sudden changes. When you get up, a significant blood volume flows into your lower extremities. This may cause drop in our blood pressure. But, as a rule, your body compensates this drop by sending by sending impulses to heart to make it to beat faster and to blood vessels to make them contract. Thus, pressure drop is neutralized. Postural hypertension develops when this process does not happen or happens too slowly. The risk of high or low pressure is increased with age and is partially associated with the natural process of aging. Moreover, with age blood supply to brain is worsened due to formation of plaques on the walls of vessels.
The pattern of loss of consciousness in patients with postural hypertension is stereotypical. Fainting usually occurs in the way well known by the patient. In such patients the arterial blood pressure is normal in lying position. They usually lose consciousness at night or in the morning right after getting up from the bed. Unlike vasodepressor fainting, loss of consciousness caused by postural hypertension occurs suddenly and without any precursors. After getting into horizontal position, the arterial pressure of the patient increases to the normal level and the patient comes into consciousness.
Causes of arterial hypotension
Very often chronic arterial hypotension is associated with serious cardiac dysfunction; it is when the heart pumps insufficient quantity of blood per unit time.
Other reasons which may cause hypotension are decreased activity of adrenal cortex or significant weight loss induced by prolonged malnutrition.
Low arterial pressure may also be a consequence of spending many days in lying position (in cases when a doctor told you to keep to bed due to some health conditions).
The risk group also includes patients who have to regularly use some certain medicines such as diuretics, drugs for decreasing arterial pressure (started due to initial increase in blood pressure), drugs for treating some psychic and neurological conditions.
Chronic arterial hypertension could be associated with vegetative nervous system disorder. It is a comparatively rare condition mainly found in elderly men. The main symptom of the diseases in such cases is considerably decreased arterial blood pressure which may lead to fainting or seizures when the patient gets up suddenly. At the same time, the patient`s pressure in lying position, no matter how paradoxical it sounds, could be even higher than the norm. Arterial hypotension is often found in teenagers. The disease may first manifest at the age of 8-9. Persistently low blood pressure rate speaks of the seriousness of the disease. The rates of blood pressure dangerous for health may vary in different age groups:
- at the age of 8-9 – the dangerous rate is below 90/50 mm Hg independently of sex;
-at the age of 11-12- below 80/40 mm Hg in boys and below 90/40 mmHg in girls;
-at the age of 14-15 below 90/40 mm Hg in boys and below 95/50 mm Hg in girls.
Teenagers suffering from hypotension usually complain of dull pressing headache in frontoparietal and parietooccipital regions, which usually starts at school and gets worse in the afternoon, dizziness and fatigue, especially in case of sudden change of body position or infrequent nutrition. Apparent absent-mindedness, inability to concentrate and bad memory are also characteristic of patients with hypotension. Some patients are unable to tolerate emotional and physical loads. Breaks during classes, outdoor physical activity and good sleep may significantly help to relieve the condition of children with hypotension.
Arterial hypotension
Hypotension is a characterized by low arterial pressure. This diseases runs in such a peculiar way, that very often the person who became its victim could be taken as a malingerer, slacker or mollycoddle.
The trouble is that, even professionals find it difficult to give definition to normal arterial pressure. It is considered that it should not exceed 140/90 mm Hg at least in people younger than 40~50 years old. However, according to statistics 20% of adult population have a higher arterial pressure. The lowest threshold of blood pressure is considered 100/60 mm Hg. Nonetheless, many people with even lower blood pressure are virtually healthy and their lifetime exceeds duration of life of people with “normal” arterial pressure.
So, how to define when does the blood pressure is out of norm and at what rate does the disease starts? Patients with genuine arterial hypotension, besides having low blood pressure rate, also feel unwell all the time. They complain of fatigue, weakness, dizziness and fainting (especially when you suddenly change your position by standing or getting up). These symptoms indicate insufficient blood supply to the brain, heart and skeletal muscles.