Intracranial hypertension syndrome

Introduction to intracranial hypertension syndrome In the lateral position, when the average cerebrospinal fluid pressure in adults exceeds 1.96 kPa (equivalent to 200 mm H2O), the intracranial pressure is increased. Intracranial hypertension (intracranialhypertension) is caused by a variety of causes of increased total volume of the cranial contents, or congenital malformation caused by a small volume of the cranial cavity, increased intracranial pressure and beyond its compensation range, followed by a common The nervous system syndrome, also known as increased intracranial pressure (increasedintracranialpressure). Increased intracranial pressure can cause a series of physiological disorders and pathological changes. If not treated promptly, patients often die due to cerebral palsy. basic knowledge The proportion of illness: 0.0003% Susceptible people: no special people Mode of infection: non-infectious Complications: disturbance of consciousness upper gastrointestinal bleeding pulmonary edema acute renal failure diabetes insipidus cerebral palsy

Causes of intracranial hypertension syndrome

(1) Causes of the disease

Common causes of increased intracranial pressure are:

1. Craniocerebral injury, such as brain contusion, intracranial hematoma, surgical trauma, extensive skull fracture, craniocerebral firearm injury, traumatic subarachnoid hemorrhage.

2. Intracranial space-occupying lesions, including various cancers, abscesses, hematomas, granuloma, cysts, brain parasites, etc., which is the most common cause of increased intracranial pressure.

3. Cerebrovascular diseases, common diseases are cerebral infarction, hypertensive cerebral hemorrhage, subarachnoid hemorrhage, hypertensive encephalopathy, etc.

4. Intracranial inflammation, such as various encephalitis, meningitis, sepsis and so on.

5. Cerebral hypoxia, such as respiratory obstruction caused by various diseases, asphyxia, cardiac arrest, carbon monoxide poisoning and hypoxic encephalopathy.

6. Poisoning and metabolic disorders, such as hepatic encephalopathy, acidosis, lead poisoning, acute water intoxication and hypoglycemia.

7. False brain tumor syndrome is also known as benign intracranial pressure.

8. Congenital anomalies, such as the developmental malformation of the aqueduct, skull base depression and congenital cerebellar tonsil malformation, etc., can cause cerebrospinal fluid reflux obstruction, resulting in secondary hydrocephalus and increased intracranial pressure; narrow cranial disease, due to the cranial cavity Small, limited the normal development of the brain, and often increased intracranial pressure.

(two) pathogenesis

1. The mechanism that causes the increase of intracranial pressure has the following aspects:

(1) The volume of brain tissue increases, which is due to cerebral edema.

(2) Increased intracranial blood volume, various causes of carbon dioxide accumulation or carbonation in the blood, can make the cerebral blood vessels dilate, cerebral blood flow increases sharply; when the hypothalamus, saddle area or brain stem damage, can cause cerebral blood vessels Regulating the dysfunction of the central nervous system, the cerebral vascular reactivity is dilated, and the cerebral blood flow is dramatically increased.

(3) Excessive cerebrospinal fluid, found in various hydrocephalus.

(4) intracranial space-occupying lesions, which are additional contents in the cranial cavity. In addition to the lesion itself, it also has a certain cranial volume, which can also cause cerebral edema around the lesion or obstruction of the cerebrospinal fluid circulation pathway, resulting in increased intracranial pressure. .

2. Pathophysiology of intracranial hypertension syndrome

(1) Systemic vasopressor response: When the autoregulatory function of the cerebral blood vessels is lost, in order to maintain the required cerebral blood flow, the body through the reflex of the autonomic nervous system causes the blood vessels around the system to contract, the blood pressure rises, and the heart beats out. Increased amount to increase cerebral perfusion pressure, accompanied by slowing of respiratory rhythm and increased respiratory depth, which increases arterial pressure, accompanied by slowing of heart rate, increased cardiac output and slowing of respiratory rhythm It is called systemic vasopressor response or Cushing three main signs, and is more common in patients with acute craniocerebral injury or acute intracranial hypertension.

(2) Relationship between intracranial pressure and volume: Langfitt et al. (1965) showed through animal experiments that due to the compensatory effect of cranial contents, the presence of external pathological factors does not necessarily cause intracranial pressure changes, cranial contents volume and cranial volume The increase in the internal pressure is not linear, but an exponential relationship. This relationship can also be expressed by intracranial plasticity and compliance. Plasticity comes from the plasticity and elasticity of soft tissue in the cranial cavity. It is the pressure change caused by the change of unit volume. It is expressed by P/V. Compliance represents the volume compensatory function in the cranial cavity. It is the volume change caused by the change of intracranial pressure. It is expressed by V/P. In the early stage of the increase of the volume of the cranial contents, there is enough space for adjustment, that is, the compliance (compensation) is strong; in the later stage of the increase of the volume of the cranial contents, the space for adjustment is less and less, and the expansion of the lesion is encountered. The resistance is getting bigger and bigger, so the intracranial pressure is sharply increased. By checking the compliance and plasticity, it is helpful to judge the severity of the increase of intracranial pressure. The clinical use method is as follows: 1m when the ventricular drainage or lumbar puncture is released. l Cerebrospinal fluid, if the pressure drop is very small, it indicates that during the compensation period, if the pressure drops more than 0.39kPa (3mmHg), it indicates that the intracranial pressure/volume curve has exceeded the critical point, that is, the compensatory function has been exhausted.

(3) cerebral palsy formation: intracranial lesions, especially intracranial space and injury, causing uneven intracranial pressure, often the brain tissue is under pressure, some brain tissue is displaced by some anatomical fissure When it comes to the lower pressure, it is brain herniation, which is the most deadly emergency of increased intracranial pressure.

Prevention of intracranial hypertension syndrome

Active prevention and treatment of primary disease is the most important preventive measure. For benign intracranial hypertension and congenital anomalies, timely diagnosis and early treatment should be made.

Complications of intracranial hypertension syndrome Complications, disturbance of consciousness, upper gastrointestinal bleeding, pulmonary edema, acute renal failure, diabetes insipidus, cerebral palsy

Consciousness disorder, vision loss, diplopia, convulsions; emotional instability, irritability or crying, or apathy, slow response, slow movements and thinking, etc., is a symptom of increasing intracranial pressure, can also be regarded as a complication Severe intracranial hypertension may occur due to hypothalamic and brainstem dysfunction. Upper common gastrointestinal hemorrhage, neurogenic pulmonary edema, acute renal failure, diabetes insipidus, cerebral sodium retention and brain Sodium deficiency syndrome.

The serious complications are cerebral palsy and central circulatory respiratory failure leading to deterioration of vital signs.

Symptoms of intracranial hypertension syndrome Common symptoms Dizziness Head enlargement Intracranial hypertension Pathological calcification Consciousness Responsive Slow bone fracture Separate thinking Slow bone destruction Blood pressure drop

Intracranial hypertension syndrome is a gradual development process, its clinical manifestations vary in severity, typical manifestations of intracranial hypertension syndrome, including clinical manifestations caused by increased intracranial pressure itself, and the cause of increased intracranial pressure The nervous system is defective.

Common symptoms and signs:

1. The headache area is uncertain and progressively worse.

2. Vomiting can be jet vomiting.

3. Optic disc edema can be accompanied by flaming bleeding and exudation.

4. The nerve palsy with double vision is the longest walking of the skull at the base of the skull. It is easy to be compressed under high intracranial pressure and produces unilateral or bilateral paralysis and diplopia.

5. Epileptic seizures There may be localized or systemic convulsions in the late stage of high intracranial pressure and coma.

6. Changes in vital signs

(1) Pulse: When the acute high intracranial pressure is applied, the slow pulse can be generated, and the intracranial pressure is increased faster, and the slow pulse is more obvious.

(2) Respiratory: In the case of acute high intracranial pressure, the initial breathing is deep and slow. When the medullary failure occurs, it turns into shallow breathing, slow irregular breathing or sigh-like breathing, and finally stops suddenly.

(3) Blood pressure: The faster the increase of high intracranial pressure, the higher the blood pressure rises reflexively, and the blood pressure drops in the late medullary failure, and cerebral shock occurs.

(4) Consciousness: Due to high intracranial pressure and cerebral edema, the cerebral cortex and brainstem reticular structure are ischemic and hypoxic, which may cause different degrees of disturbance of consciousness. Chronic high intracranial pressure may first cause restlessness and then sleepiness to Coma, high intracranial pressure and consciousness disorder are not necessarily proportional, depending on the location, such as subthalamic tumor or brain stem contusion consciousness disorder can be very heavy, intracranial pressure is not necessarily high.

(5) Pupil: In the early stage, it suddenly becomes small or small, and if the side is scattered, the light reaction disappears, indicating that the sacral leaf hook is formed.

7. Tinnitus, vertigo, high intracranial pressure can make the road, the vestibule is stimulated, and the inner ear is congested, and some patients may have tinnitus and dizziness.

The main clinical manifestations are "three main signs": headache; nausea and vomiting; fundus optic edema, other common manifestations of disturbance of consciousness, vision loss, diplopia, convulsions and cortical rigidity, some can be expressed as emotional instability, easy to irritate or cry , or mental symptoms such as apathy, unresponsiveness, slow movements and thinking.

In infants and young children, headache symptoms are often not obvious, often scalp venous engorgement, head enlargement, enlargement of the cardia, separation of the sutures, increased or increased anterior tendon tension, and a broken pot sound (Macewn sign).

For chronic intracranial hypertension syndrome, the saddle can be found on the skull X-ray film, especially the saddle back and anterior and posterior sacral bone destruction or absorption, the skull is diffusely thin and thin, and the cerebral gyrus is increased and deepened. Children before the age can see the widening and separation of the cranial suture. The younger the age, the more common. Because of the intracranial space, the normal calcification point of the pineal gland can be seen, pathological calcification, local hyperplasia or destruction of the skull, inner ear. Abnormal changes in the nerves of the brain and other brains.

Computed tomography (CT) or magnetic resonance imaging (MRI) can detect intracranial space-occupying lesions and confirm the diagnosis, and these two tests are safe, simple, accurate and reliable. For those with objective signs or nerves with increased intracranial pressure Patients with a positive finding or a clinically highly suspected increase in intracranial pressure should be examined early for CT or MRI.

For patients with increased intracranial pressure, lumbar puncture has the risk of promoting cerebral palsy. It should be prohibited or carefully worn. If necessary, the waist should be closed after the dehydrating agent is applied. Strengthen dehydration and close observation.

Examination of intracranial hypertension syndrome

1. Cerebrospinal fluid examination pressure is generally higher than 200mmH ₂ O, CSF routine laboratory tests are more normal, for patients with increased intracranial pressure, lumbar puncture has the risk of promoting cerebral palsy, for clinically suspected increased intracranial pressure, while other examinations If there is no positive finding, in the absence of posterior cranial fossa or neck stiffness, it can be considered carefully. It should be done after the dehydration agent is applied.

2. Necessary selective examination According to the possible causes, blood routine, blood electrolyte, blood sugar, immune project examination, and differential diagnosis.

3. For chronic intracranial hypertension syndrome, the skull X-ray film can be found in the saddle, especially the saddle back and anterior and posterior sacral bone destruction or absorption, the skull is diffusely thin and thin, and the cerebral gyrus is increased and deepened. .

4. For patients with positive signs of increased intracranial pressure or positive findings in the neurological examination or clinically highly suspected increase in intracranial pressure, CT or MRI should be performed early.

Diagnosis and identification of intracranial hypertension syndrome

diagnosis

Typical intracranial hypertension syndrome has headache, vomiting and optic disc edema. Among them, optic disc edema is the most objective. According to this sign, the diagnosis is not difficult, but in the early stage of acute intracranial hypertension or chronic intracranial hypertension, More than disc edema, patients may have only headache and / or vomiting, easily misdiagnosed as a functional disease, with serious consequences, therefore, every headache and / or vomiting patients should be treated with caution, alert to the possibility of increased intracranial pressure.

Differential diagnosis

The early stage of the disease should be differentiated from functional diseases such as vascular headache, and the primary disease leading to intracranial hypertension syndrome needs to be identified.

1. craniocerebral injury (braniocerebral injury) caused by any cause of brain injury caused by brain contusion, cerebral edema and intracranial hematoma can increase intracranial pressure, acute severe craniocerebral injury can occur intracranial pressure Increased, a small number of patients can appear later, such as chronic subdural hematoma, patients with craniocerebral injury often quickly into a coma, accompanied by vomiting, intracerebral hematoma can be partial hemiplegia according to different parts, aphasia, convulsions, etc., brain CT can directly determine the size, location and type of intracranial hematoma, as well as intraventricular hemorrhage that cannot be diagnosed by cerebral angiography.

2. Cerebrovascular disease (cerebrovascular disease) is mainly hemorrhagic cerebrovascular disease, hypertensive cerebral hemorrhage is the most common, generally onset is more urgent, the increase in intracranial pressure is 1 to 3 days to develop peak, patients often have different The degree of consciousness disorder, manifested as headache, dizziness, vomiting, limb paralysis, aphasia, incontinence, etc., often have significant blood pressure rise in the onset, most patients with meningeal irritation positive, cerebrospinal fluid pressure increased and often bloody, brain CT can Determine the size of the bleeding and the location of the bleeding.

3. Hypertensive encephalopathy Hypertensive encephalopathy refers to acute and severe brain dysfunction caused by sudden increase in blood pressure, common in acute hypertension, acute and chronic nephritis or eclampsia, or pheochromocytoma or Taking monoamine oxidase inhibitors while taking tyramine-containing foods, lead poisoning, Cushing's syndrome, etc., often sudden onset, blood pressure suddenly increased significantly to 33.3/20kPa (250/150mmHg), diastolic blood pressure increased more than systolic blood pressure Significant, often accompanied by severe headache, nausea, vomiting, neck stiffness and other symptoms of increased intracranial pressure, neuropsychiatric symptoms including visual impairment, hemiplegia, aphasia, epilepsy-like convulsions or limb muscle rigidity, disturbance of consciousness, etc., the fundus may be hypertensive , retinal artery spasm, and even retinal hemorrhage, exudate and optic disc edema, CT examination showed cerebral edema, narrowing of the ventricles.

4. Intracranial tumour can be divided into primary intracranial tumors and metastases that are metastasized from other parts of the body to the brain. The common feature of intracranial pressure caused by brain tumors is chronic progressive. Increased intracranial pressure, although the symptoms may be slightly ups and downs during the course of the disease, but the general trend is gradually worsening, a small number of patients with increased intracranial pressure can suddenly turn into an acute attack, depending on the location of the tumor can be accompanied by different symptoms, such as Changes in visual field of vision, pyramidal tract damage, seizures, aphasia, sensory disturbances, psychiatric symptoms, cerebellopontine angle syndrome, etc., CT can identify the location and nature of tumor growth.

5. Brain abscess (brain abscess) often have primary infections, such as otogenic, nasal or traumatic, systemic symptoms of acute inflammation at the onset of blood, such as high fever, chills, meningeal irritation Symptoms, increased white blood cells, blood sedimentation, increased number of white blood cells in the cerebrospinal fluid of the lumbar spine, but after the abscess matures, the above symptoms and signs disappear, only manifested as increased intracranial pressure, with or without focal neurological signs The course of brain abscess is generally short, and mental retardation is more serious. CT scan often shows circular or oval density to reduce shadow. After contrast injection, the edge image is obviously enhanced, and the thin and smooth ring density increases shadow, and the abscess The surrounding low-density brain edema zone is more pronounced.

6. Brain infectious disease Brain infection refers to inflammatory diseases of the brain and meninges caused by bacteria, viruses, parasites, rickettsia, spirochetes, etc., showing acute or subacute intracranial hypertension. A small number of manifestations of chronic intracranial hypertension, often onset of infection symptoms, such as fever, general malaise, increased blood, etc., some cases have consciousness disorders, mental disorders, myoclonus and seizures, etc., severe cases develop to deep within a few days Coma, the important feature is often frequent focal symptoms, such as hemiplegia, aphasia, binocular deviation, partial epilepsy, involuntary movement, other neck stiffness, meningeal irritation, etc., cerebrospinal fluid often have inflammatory changes, Such as cerebrospinal fluid leukocytosis, increased protein, or decreased sugar or chloride, positive complement test, etc., head CT can be seen inflammatory changes.

7. Hydrocephalus Hydrocephalus Due to various reasons, the cerebrospinal fluid in the ventricular system is increasing, and the brain parenchyma is correspondingly reduced. When the ventricle is enlarged and accompanied by increased intracranial pressure, it is called hydrocephalus, also known as progressive or high. Pressure hydrocephalus, ventriculography showed a significant enlargement of the ventricles, CT can detect tumors, accurately observe the size of the ventricles and can show the degree of edema around the ventricles.

8. Benign intracranial hypertension (benign intracranial hypertension), also known as "pseudo-brain tumor", patients with only increased intracranial pressure symptoms and signs, but no space-occupying lesions, the cause may be arachnoiditis, ear source Hydrocephalus, venous sinus thrombosis, endocrine diseases, etc., but often unclear, clinical manifestations in addition to increased chronic intracranial pressure, generally no focal signs.

9. The increase of intracranial pressure caused by other systemic diseases is also quite common in clinical, such as toxic encephalopathy, uremia, water and electrolytes and acid-base balance disorders, diabetes coma, hepatic coma, food poisoning, etc. The development of the disease to the severity can have increased intracranial pressure, combined with the history of the disease and systemic examination can make a clear diagnosis.

When the intracranial pressure is increased to cause the brain tissue to be displaced into the dura mater or the cranial hole, it is the cerebral palsy. It is common to have the sacral sacral sputum (Tianmu , the cerebral hiatus, the cerebellar incision) and the occipital foramen (Cerebellum cerebral palsy) two kinds.

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