Hypertensive cerebral crisis is a sudden increase in blood pressure to critical figures, leading to a violation of cerebral circulation. Depending on the type of hypertensive cerebral crisis, its clinical manifestations may be headache and other symptoms of increased intracranial pressure, mental abnormalities accompanied by focal symptoms or a combination of these symptoms. Disease is treated with the complex use of antihypertensive and sedative therapy (generally accepted for the relief of a hypertensive crisis), vasoactive drugs (antispasmodics or venotonics) and symptomatic agents selected in accordance with the type of crisis.
I10 Essential [primary] hypertension
Hypertensive cerebral crisis is a type of hypertensive crisis. Most often it develops against the background of hypertension, since its course is accompanied by an increased load on the apparatus responsible for regulating the tone of cerebral vessels. Pathology can also occur in other diseases that lead to a significant increase in blood pressure (atherosclerosis, pyelonephritis, glomerulonephritis, pheochromocytoma, diabetic nephropathy, primary hyperaldosteronism, etc.). It is noted that in half of cases, hypertensive cerebral crisis occurs after stressful situations. Additional factors leading to a violation of the regulation of the tone of the cerebral vessels are: a sudden change in the weather, hypothermia, overeating, physical overload, etc.
According to the mechanism of development of pathological changes that occur with arterial hypertension in the vessels of the brain, there are: angiohypotonic, ischemic and complex hypertensive cerebral crisis. Angiohypotonic hypertensive cerebral crisis occurs when the tone of the cerebral vessels decreases and blood is deposited in the venous system, which is accompanied by an increase in intracranial pressure. Ischemic hypertensive cerebral crisis is caused by oxygen starvation of brain tissues resulting from a sharp reflex spasm of cerebral arteries in response to an increase in blood pressure. A complex hypertensive cerebral crisis is a combination of both of these mechanisms.
Depending on the presence/absence of complications, clinical neurology classifies hypertensive cerebral crisis as complicated or uncomplicated. Complications include: transient ischemic attack, ischemic stroke, rupture of cerebral aneurysm, eclampsia in pregnant women.
Normally, the system of regulation of cerebral circulation works in such a way that with an increase in systemic blood pressure, there is an increase in the tone of the cerebral arteries, which allows avoiding the entry of excessive amounts of blood into the cerebral vessels. Failure of this compensatory mechanism may be manifested by insufficient or excessive tonic reaction of the cerebral arteries.
In the case when, with an increase in blood pressure, the tonic reaction of the cerebral vessels is insufficient, an excess amount of blood breaks into the blood vessels of the brain. In this case, the second compensatory mechanism should be triggered, which consists in increasing the tone of venous vessels. It accelerates the outflow of excess blood from the cranial cavity. If a sufficient increase in the tone of the venous system does not occur, then an angiohypotonic hypertensive cerebral crisis develops. It is based on stagnant phenomena arising in the venous system of the brain, accompanied by the accumulation of excess fluid in a limited space of the cranial box (hydrocephalus), which leads to an increase in intracranial pressure.
Excessive increase in the tone of the arteries of the brain in response to a jump in blood pressure leads to a violation of blood supply to brain tissues with the development of hypoxia (oxygen starvation) in them and the emergence of an ischemic variant of a hypertensive cerebral crisis. At the same time, the brain structures most sensitive to hypoxia (the cerebral cortex) suffer first of all. The uneven architectonics of the cerebral vessels, as well as the possible addition of local angiospasm, lead to the appearance of foci with more pronounced ischemia, which are associated with the clinically observed focal symptoms.
The pathogenesis of a complex hypertensive cerebral crisis includes hypotension of cerebral vessels with blood deposition in the venous system and ischemia of certain parts of the brain due to deterioration of capillary blood flow due to shunt discharge of blood from the arteries into the veins, bypassing the capillary network.
Angiohypotonic hypertensive cerebral crisis usually develops against the background of a typical and habitual headache for hypertensive patients, which is localized in the occipital region or occurs as a feeling of heaviness in the head. A characteristic sign of such a headache is its intensification in the position of the body, which complicates the venous outflow from the cranial cavity (straining, bending, lying down, coughing). By itself, a headache of this nature is already a sign of cerebral angiodystonia, but it often passes in an upright position of the body and when taking caffeinated beverages.
The onset of a hypertensive cerebral crisis is indicated by the spread of headache into the retroorbital region. At the same time, patients complain of the appearance of pressure on the eyes and behind the eyeballs. A distinctive feature is its occurrence with a moderate rise in blood pressure (170/100 mm Hg). Then there is a rapid (within an hour) increase in headache and its diffuse spread throughout the head. Nausea appears, repeated vomiting, bringing some temporary relief. Angiohypotonic hypertensive cerebral crisis, as a rule, is accompanied by vegetative reactions: increased sweating, tachycardia, wave-like breathing, sometimes facial cyanosis. The late phase of the crisis is characterized by increasing inhibition, nystagmus, dissociation of tendon reflexes. During this period, blood pressure can be at the level of 220/120 mmHg or more, but in some cases it does not rise above 200/100 mmHg.
Ischemic hypertensive cerebral crisis is observed much less frequently than angiohypotonic and is characteristic mainly for hypertensive patients who do not suffer from headaches and tolerate an increase in blood pressure well. Often, an ischemic hypertensive cerebral crisis develops against the background of very high blood pressure figures, sometimes exceeding the limits of the tonometer scale. Clinical manifestations of such a crisis in the initial period may go unnoticed. They relate mainly to disorders of the mental sphere in the form of increased energy, excessive emotionality or external efficiency. Then there is irritability, followed by depression and tearfulness, possibly aggressive behavior. At the same time, due to the lack of criticism, patients themselves cannot adequately assess their condition.
Further development of ischemic hypertensive cerebral crisis is accompanied by the appearance of focal symptoms: visual disturbances (flashing of “flies” in the eyes, diplopia), sensitivity disorders (numbness, tingling, etc.), dysarthria (speech disorders), shaky gait, vestibular ataxia, asymmetry of tendon reflexes.
A complex hypertensive cerebral crisis begins with clinical manifestations characteristic of the angiohypotonic variant of a cerebral crisis, but it often occurs against a background of significantly elevated blood pressure. As the crisis develops, during the period of pronounced clinical manifestations, focal symptoms appear, typical for the ischemic variant of a cerebral crisis. At the same time, the nature of the emerging focal symptoms depends on the location of the ischemic areas of brain tissue.
Hypertensive cerebral crisis is diagnosed by a therapist, neurologist or cardiologist based on a typical clinical picture, data on the development of existing symptoms and blood pressure measurements. Additional instrumental studies are usually carried out after the patient is provided with emergency care and are aimed at in-depth diagnostics of the state of cerebral circulation and the cardiovascular system. They may include ECG, daily blood pressure monitoring, rheoencephalography, Echo-EG, EEG, ultrasound of the vessels of the head, consultation of an ophthalmologist, ophthalmoscopy, perimetry, MRI of the brain.
It is necessary to differentiate hypertensive cerebral crisis from hemorrhagic stroke, TIA, ischemic stroke, acutely developing hydrocephalus in brain tumors and cerebrospinal fluid disorders of other etiology.
Ischemic and mixed hypertensive cerebral crisis are indications for hospitalization of the patient. The need for inpatient treatment for uncomplicated angiohypotonic variant of the crisis depends on its severity. In any case, hypertensive cerebral crisis requires complex treatment, including antihypertensive and tranquilizing therapy common to all types of hypertensive crisis, the appointment of vasoactive drugs, the choice of which depends on the type of cerebral crisis, and symptomatic treatment. The patient must observe bed rest until the blood pressure stabilizes and the regression of the neurological symptoms that have arisen.
Hypotensive therapy of cerebral crisis is carried out in accordance with the general principles of emergency care for hypertensive crisis. It is possible to use vasodilators, calcium channel blockers, beta-blockers, ACE inhibitors, etc. The need to prescribe tranquilizers (diazepam, chlordiazepoxide, phenazepam, etc.) is due to the fact that in half of the cases, the crisis develops against the background of emotional stress and is often accompanied by anxiety and fear.
The administration of vasoactive drugs is carried out mainly by intravenous drip or jet method. Ischemic hypertensive cerebral crisis is most effectively stopped by the administration of vincamine. It is possible to use papaverine, drotaverine, eufillin. Treatment of angiohypotonic hypertensive cerebral crisis is carried out by venotonics. The introduction of caffeine gives a good effect, but it is contraindicated in IHD, ventricular extrasystole, increased individual sensitivity. In the treatment of a complex hypertensive cerebral crisis, caffeine is used along with vincamine or drotaverine.
The main way to prevent hypertensive cerebral crisis is adequate hypotensive therapy of patients with arterial hypertension. For preventive purposes, even with moderately elevated blood pressure figures, work requiring lifting weights, an inclined posture or a fixed body position should be excluded. It is necessary to avoid hypothermia of the head, emotional overstrain, with constipation, follow a diet and take laxatives. With the regular occurrence of morning headache, it is better for the patient to sleep on a high pillow and arrange hiking before going to bed.
An increase in headache may be a harbinger of an incipient cerebral crisis. To avoid the development of a crisis in such a situation, it is necessary to massage the neck-collar area, warm your head with a warm shower or a hairdryer, drink strong tea; with an intense headache, take caffeine tablets or seduxen. If a hypertensive person has an increase in headache, then a two-week course of bellaspon (belloid) or vincapan (vincaton) is recommended for him.