The most characteristic manifestation of hypertension is an increase in blood pressure.
Usually, high blood pressure in hypertension can be detected by examining the pulse.When palpating the pulse in the radial artery, a hard pulse (p. durus) caused by increased intravascular pressure and tonic contraction of the arterial walls is determined.However, during hypertension, due to a slight decrease in the lumen of the medium-sized artery, the filling of the pulse changes little.When recording pulse fluctuations graphically (in a sphygmogram), the pulse wave is low, rounded, and has a gentle rise and fall (pulsus tardus);the dichroic wave is almost imperceptible.
Studying blood pressure using the auscultatory method is still the best method for simultaneously determining systolic, diastolic and pulse pressure.All three values are usually elevated in hypertension.Systolic increases most significantly;diastolic increases to a lesser extent.
If we compare the percentage increase of systolic and diastolic pressure in hypertension with the average values of both pressures in normal conditions, the increase will be almost equal.So if we take 120 mm Hg as the normal value for systolic pressure and 70 mm Hg for diastolic pressure.Art., then with blood pressure equal to 160 mm Hg.Art.(maximum) and 90 mm Hg.Art.(minimum), the increase against the norm for both values will be almost the same (90 compared to 70 and 160 compared to 120).With a reading of 180/100 mmHg.Art.at first sight it seems that the systolic increases more significantly than the diastolic (180 vs. 120 and 100 vs. 70);if we compare with normal coefficients, the increase in percentage expression will be almost equal.
Often in the initial period of hypertension (stage I) there is an increase in either systolic or diastolic pressure (usually the first, less often the second).Perhaps it depends on the baseline level before the disease (each person is individual).
The relationship between diastolic and systolic blood pressure is influenced by:
- the degree of elasticity of the walls of large arteries,
- force of heart contraction.
It is known that a decrease in vascular elasticity contributes to an increase in systolic pressure (most clearly this occurs with atherosclerosis of the central vessels).
Changes in the elasticity of the walls of large vessels are observed in hypertension, which is reflected by an increase in pulse pressure.Under the same conditions, when the heart begins to weaken, the amplitude becomes smaller: systolic pressure decreases, diastolic pressure remains high.
Already at the beginning of the disease there is a tendency to pressure reactions.Blood pressure measurement shows that in some patients its level does not exceed the upper limit of the age norm, but the values obtained during the measurement are higher than usual for a certain person, while in others it exceeds the upper limit of the age norm.In hypertension, the increase in pressure is observed under the influence of various influences - mental, emotional, reflexes, and remains at a high level from several minutes to several hours.
The first measurement usually gives higher numbers (random pressure) than repeated measurements taken 5-10-15 minutes later.The difference between the value of the accidental and the main pressure is defined as "additional pressure";its value is significantly higher in people suffering from hypertension than in healthy people.The main pressure is the pressure obtained during the study of the basal metabolic rate (that is, in bed, in the morning after sleep, on an empty stomach).After repeated measurements under normal conditions, the smallest value of the indicator is conventionally called "almost basic pressure".
"Additional pressure" undoubtedly refers to the degree of mental (emotional) arousal or tension of the patient at the moment and the degree of excitement of the nervous system that regulates blood pressure.Experience shows that the amount of additional pressure in patients in the prehypertensive period is usually more significant than in people who do not show a tendency to hypertension.
When comparing the degree of pressor effect of certain nerve influences, it should be noted that the most acute stimulus is the word.Therefore, it is not an exaggeration to say that the second signaling system influences the high blood pressure level in hypertension and people prone to it.
Tests for high blood pressure in hypertension
They also tried to determine the tendency to hypertension through reflex irritations.In this regard, special attention was paid to the so-called cold test.After a short rest, the subject's blood pressure is measured in a lying position, then the hand of the other hand is immersed in water at a temperature of 4 ° for one minute;measure the level at the moment of immersion and then every 30 seconds until level.An increase in systolic pressure of more than 20 mmHg.Art., more than 15 mm Hg diastolic.Art.serves as an indicator of increased pressure reactivity.Those who discovered it were called "hyperreactors", and those who did not find it were called "hyporeactors".Among healthy people, hyperreactors make up 15%.
The cold test received mixed reviews.The conditions under which the test is conducted play an important role in the pressor effect for a given test.Due to reduced vascular tone, a warm person has a lower blood pressure response to cold than the same person at a colder outside temperature.Reflex response to cold depends on usual temperature effects, occupation and living conditions.It is known that people are addicted to the temperature factor.The cold test may be weak in hardened people, and strong in people sensitive to cold.
The cold test is based on the reflex response of the vasomotor center in response to a sudden thermal (and partially painful) stimulation in the periphery.After taking alcohol, bromine and barbiturates, the pressor response to cold is weakened.
Sometimes the answers to the cold test are paradoxical: high blood pressure does not occur in hypertension, and sometimes it even decreases.
It is interesting to compare these data with the results of determination of blood pressure after exposure to heat.People suffering from hypertension often experience an increase in blood pressure, not a decrease, when the hand is heated (the hand immersed in warm water does not turn red, it turns pale).As a result, cold and heat can sometimes produce the same type of pressure vasoconstrictor effect.
Temperature effects can be used as a difficult method to assess the reactivity of the hypertensive apparatus during hypertension, because they do not reflect the characteristics of the disorders underlying hypertension.Vascular tests using pharmacological agents have been suggested.One of them is the test with glycerol trinitrate.After taking 2 drops of glycerol trinitrate (under the tongue), blood pressure (systolic and diastolic) decreases significantly.The decrease is more noticeable in people whose blood pressure is sharply elevated due to hypertension.The reduction is especially important with unstable blood pressure;Sometimes such a reduction is observed in persistent hypertension.In the later stages of hypertension (with the development of arteriolosclerotic changes in the kidneys), a nitroglycerin test gives a slight decrease in hypertension, which can be used to diagnose renal forms (or stages) of hypertensive conditions.
The same results (depressor effect) are obtained by a test with inhalation of isoamyl nitrite.Glycerin trinitrate, like isoamyl nitrite, acts mainly through central vasomotor devices, thereby characterizing the increased excitability of these centers during hypertension.
The sodium amytal test has gained some popularity.0.2 g of sodium amytal is administered 3 times every hour to a bedridden subject;blood pressure is measured before giving the drug and every half hour after taking it (within 3 hours).The difference between baseline and trough levels determines the magnitude of the depressant effect.After taking the second powder, sleep usually occurs.Typically, sodium amytal helps to reduce blood pressure not only in the first hours, but also in the following days, sometimes even for several days;the patient's well-being improves.However, this effect is not always observed: some patients have intolerance to the drug.
Unlike the nitrite test, which causes a rapid drop in pressure, when tested with amytal sodium, it decreases gradually.After taking sodium amytal, its rate of decrease is especially important at the beginning of the disease.In the late period, when there are arteriolosclerotic changes in the kidneys, the reduction is usually small or absent.
Since the effect of barbiturates is undoubtedly central in nature, a test with amytal sodium characterizes the state of the devices that regulate blood pressure in cortical and subcortical regions.When using different doses of the drug (small and large), it is possible to judge the phase states of vasopressor nerve centers with blood pressure (sometimes large and small doses have the same effect, or small doses have a depressant effect that is different from large doses).
In addition to tests based on the depressor effect, many tests based on pressure activity have been proposed - cessation of breathing, inhalation of carbon dioxide, intake of phenamine, but they do not adversely affect the condition of patients, although they do not determine the tendency to hypertension in its early stage and in the so-called premorbid state.
Having detected a tendency to a short-term increase in blood pressure in a certain person, you should not immediately diagnose hypertension, much less inform the examined person about it.Under favorable environmental conditions, pressure reactions can completely disappear.
High blood pressure depending on the stage of hypertension
In the early stage of hypertension, increased pressure occurs only periodically (transient phase).The more difficult the patient's life conditions are from a neuropsychological point of view, the longer and more frequent the periods of high blood pressure in hypertension, and the shorter and rarer the normal levels.Adherence to treatment measures and regimen is of great importance.Under the influence of rest and treatment, in the initial transitory phase of hypertension, with its benign course, the indicator often returns to normal for a long time.
An increasingly persistent tendency to increase blood pressure and maintain its pathological level during hypertension indicates that the disease is progressing to stage II.Blood pressure is unstable in stage A of stage II (labile phase).Its level can vary significantly.Although it is not maintained at this level for a long time under the influence of rest, it decreases to a near-normal level in a short period of time.Under the influence of treatment, however, it is possible to achieve a long-term reduction of the indicator to the norm.
Blood pressure with hypertension can vary widely during the day.The morning is usually lower than the evening.It increases slightly after eating, then gives a significant decrease.During night sleep, it decreases more sharply in hypertension than in healthy people.
As the disease progresses, blood pressure becomes more firmly established at a high level (stage B of stage II, stable).True, even at this stage, it sometimes has periods of decline.Sometimes remission occurs under the influence of long-term therapy for a sufficiently long time.But this stage is usually characterized by persistent and high hypertension.At this stage, depressor tests show the functional nature of high blood pressure in hypertension.
In stage III, blood pressure usually rises continuously.Hypertension is maintained by a number of factors, among which undoubtedly the kidney is involved.However, during strokes or under the influence of heart failure, a decrease in blood pressure is observed with a decrease in the excitability of vasopressor centers (decompensation due to excessive straining of the contractile function of the hypertrophied heart).Moderate heart failure has little effect on the level of the indicator;sometimes it even increases during this period (stagnation factor).
As for venous pressure in hypertension, it is usually in the normal range and increases only with heart failure.True, in some patients, even in the early stages of the disease, slightly elevated values of venous pressure can be detected, which led to the excitation of the "venomotor center", as a result of which the tone of the venous walls increases (but we cannot judge the latter, because it is usually measured by intravenous blood pressure).It is difficult to determine blood pressure in capillaries.Capillaroscopically, narrowing of precapillary arterial bends and widening of venous bends is usually determined in the nail bed;Variability of the capillary pattern ("their play") is typical.