Cerebral edema

cerebral is a collection of fluid that forms in a tissue of the brain, pressing against the blood capillaries of the affected area. This compression blocks the flow of blood and the supply of oxygen, first damaging the affected area of ​​the brain and then causing its death.
The formation of a cerebral edema can be caused by different causes; most often, it occurs after a head injury or stroke, but it can also occur as a result of an infection or severe diabetes.
The symptoms of a cerebral edema are numerous and can vary greatly from patient to patient.
Diagnosis must be rapid and therapy timely, as cerebral edema is a clinical emergency which, if not treated in time, can cause permanent brain damage.

and is mainly composed of plasma; after having accumulated inside and / or outside the cells of the brain, this liquid begins to compress the blood capillaries and the walls of the skull. This compression, called intracranial pressure, blocks the supply of oxygen and nutrients, slowly causing the death of the edematous brain tissue and a severe headache.
Furthermore, again because of the edema, the cerebrospinal fluid (or CSF) could remain confined in the cerebral ventricles, where it is produced, without being able to move. This situation, better known as hydrocephalus, causes the CSF to accumulate in excessively inside the brain, further worsening the disorders caused by edema.

(i.e. a spill of blood). The blood, which escapes in this way, increases the intracranial pressure and worsens the cerebral edema.

Ischemic stroke. The term stroke identifies a serious pathological condition, which occurs when the blood supply to the brain is interrupted or severely reduced. In the case of ischemic stroke, the blockage of the cerebral blood supply depends on a blood clot (a thrombus or an embolus). Without blood, the affected brain areas no longer receive oxygen and slowly begin to die. This deleterious mechanism lays the foundation, in some cases, for the formation of a cerebral edema.

Hemorrhagic stroke and hypertension. Stroke is hemorrhagic when the lack of blood and oxygen supplies results from the rupture of a blood vessel. This blood loss, also known as cerebral haemorrhage, increases intracranial pressure and promotes the onset of edema. Among the main causes of haemorrhagic stroke c "is" hypertension (ie "high blood pressure), which is therefore also considered one of the main risk factors for cerebral edema.

Infections. Infections are diseases caused by pathogens, such as viruses, bacteria and parasites; those that can give rise to a cerebral edema are: meningitis, encephalitis, toxoplasmosis and subdural empyema. The latter are collections of pus located between the dura mater and arachnoid meninges.

Brain tumors. A brain tumor is an abnormal mass of cells that grows inside the brain. The formation of a tumor, in addition to being a possible cause of cerebral edema, favors the increase in intracranial pressure, as the presence of the skull reduces the space available to the tumor mass. This, in fact, as it grows, pushes on the bone walls and especially on the surrounding brain areas.

High altitude (or altitude sickness). Being at a high altitude (from 2500 meters upwards) can cause various ailments, such as headaches, nausea, dizziness, shortness of breath, palpitations, etc. In some individuals, these disorders can get worse and worse, leading to brain edema and pulmonary edema. The explanation of how to get to this situation has not yet been clarified, however, at the first symptoms of the so-called altitude sickness, it is advisable not to rise further in altitude and, possibly, to descend towards the valley. Attention, below 2500 meters the Disorders that someone may experience are not generally considered altitude sickness and usually do not have serious consequences.

Abuse of opiate drugs. Opiate drugs (morphine, codeine, oxycodone, etc.) are taken for their strong pain relieving powers. However, their excessive use is at the origin of various complications, including cerebral edema.

Diabetes. It is a metabolic disease caused by "impaired insulin activity". In particular, cerebral edema can arise due to a condition, which affects some diabetic patients, called diabetic ketoacidosis.

Dizziness

Irregular heartbeat

Loss or changes in vision (blurred vision, double vision, etc.)

Pain and stiffness in the neck

Memory loss (amnesia)

Motor impairments, such as difficulty walking and / or balance

Lack of coordination in movements

Difficulty speaking (aphasia)

Feelings of numbness, malaise and lightheadedness (or lethargy)

Epilepsy attacks

Confusion or loss of consciousness

Difficulty in understanding

Fever

Hydrocephalus

AGE OF THE PATIENT

The age of the patient has a decisive influence on the consequences of a particular symptom, hydrocephalus.

Figure: A characteristic symptom of cerebral edema is headache

This condition, if it occurs in childhood, causes disorders such as increased head circumference, loss of appetite, difficulty in sucking and feeding, deviation of the eyes downwards, irritability and sudden mood changes; all of these signs do not occur, or are not as pronounced, among adults.
Among these pathological manifestations, the increase, in the infant, of the head circumference is the most characteristic, as it is due to the not yet complete welding of the skull bones.

BRAIN AREA AFFECTED

The brain is divided into several areas and each of them controls distinct functions.
It follows that a cerebral edema arising at the level of the occipital lobe of the brain, has different consequences compared to a cerebral edema developed at the level of the temporal or frontal lobe. For example, if the occipital lobe is affected, visual disturbances will occur, while if the temporal lobe is affected, spoken language is lost.

Figure: hydrocephalus in the child

The exact location of the affected area of ​​the brain is very important, because it allows you to plan the surgery in the best possible way.

COMPLICATIONS

If you do not intervene in a timely manner, cerebral edema can produce permanent brain damage and, sometimes, have lethal consequences. All this, moreover, can be made even more serious by the type of triggering cause, as the more it is difficult to do so. treatable, the more its effects are irreversible.
The possible complications of cerebral edema include: coma, paralysis, cognitive handicaps of various kinds, developmental delay (among young patients), muscle weakness and permanent motor and learning deficits.

and, if there is any suspicion of diabetes and or infection, a patient "blood test".

OBJECTIVE EXAMINATION

During the physical examination, the doctor asks the patient to describe the symptoms and if he remembers an event that triggered them.
Trauma to the head, having suffered from particular diseases or diabetes, having been in the mountains at high altitudes or having taken opiate drugs are all useful information for a correct diagnosis.
After this rapid investigation, the patient is examined to assess the extent of the symptoms and subjected to the classic checks of pressure and heartbeat.

Warning: at this stage of the diagnosis, the doctor may need to speak to a relative or close friend of the patient, as the latter may not remember certain episodes and inadvertently omit some very useful information.

NEUROLOGICAL EXAMINATION

All those who complain of symptoms such as headaches, loss of motor skills, cognitive deficits, language deficits and / or vision loss, as they indicate brain involvement, require a neurological examination.
People with suspected cerebral edema undergo quick checks of hearing, vision, speech, balance, coordination and reflexes. The partial or total loss of one or more of these abilities can help the physician to understand which area of ​​the brain is affected by edema.

RADIOLOGICAL EXAMINATIONS

The radiological examinations consist of a nuclear magnetic resonance (MRI) and / or a computed axial tomography (CT), both in the brain.

Figure: X-ray examination of a brain affected by cerebral edema. Edema is the dark area on the right brain hemisphere. From the site: http://en.wikipedia.org/

The images provided by these tests clarify the location and magnitude of the brain edema; moreover, in the event that the disorder originated from a tumor or a stroke, they also show the signs of these two possible causes.
Therefore, MRI and CT scan have a fundamental diagnostic value, especially if the patient has declared that he is neither diabetic nor addicted to opioid drugs.

BLOOD ANALYSIS

Blood tests are carried out if there is a suspicion that the cerebral edema is due to diabetes, an infectious agent or the abuse of opioid drugs. Therefore, these diagnostic checks are aimed at identifying the triggering causes, not so much brain edema.

. It is the therapeutic administration of oxygen, carried out through a respirator or in a hyperbaric chamber (hyperbaric oxygen therapy, OTI). Thanks to oxygen therapy, a better oxygenation of all tissues and organs of the patient is guaranteed, including the brain.

Osmotherapy. The goal of osmotherapy is to reduce high intracranial pressure. To achieve this, osmotic agents such as mannitol are administered intravenously. These substances, once in the blood, "draw" back the edematous fluid. , passed from the vessels to the intra- and extra-cellular spaces of the brain. Osmotherapy is not always effective, indeed, in some cases, it can worsen cerebral edema; therefore, its execution requires the utmost attention.

Pharmacological therapy. The most suitable drugs against cerebral edema are corticosteroids, diuretics and, if at the origin of the disorder there is a blood clot, anticoagulants. The pharmacological administration, therefore, depends on the triggering causes.

Ventriculostomy. It is the therapeutic procedure adopted in case of hydrocephalus. It is performed by a surgeon who, through a hole made in the patient's skull, inserts a thin plastic tube into the cerebral ventricles. This catheter is then used to aspirate excess CSF, which helps to raise intracranial pressure.

Surgery. There are two possible surgical interventions. The first procedure, known as decompressive craniectomy, involves removing the part of the skull against which the edema-affected area of ​​the brain pushes. In this way, in fact, the intracranial pressure is reduced.
The second procedure, on the other hand, is foreseen only in the case of tumor, stroke or hemorrhage in the brain (a diabetic or suffering from altitude sickness does not require this intervention, for obvious reasons) and consists in the repair and / or removal of what triggered the edema.

Induced hypothermia. By induced hypothermia, we mean the voluntary lowering, to 32-33 ° C, of ​​an individual's body temperature (including the brain). The purpose of this treatment is to slow the progression of brain damage and save the brain from lack of oxygen. Induced hypothermia is an innovative method of treatment which, in Italy, is not yet widespread, as its real benefits are still being debated.

with a healthy lifestyle and with the right physical exercise.

Avoid smoking.

Give the body enough time to get used to the high altitude (acclimatization), in order to avoid the danger of a cerebral edema from altitude sickness.