Brain Edema: Types, Symptoms, Causes And Treatment
If someone tells us that they have fluid retention, we are probably thinking of a person with their legs or some part of their body inflamed and swollen. Said this way, it may seem like something of little relevance, easily treatable and hardly a nuisance, as in fact this is the case in many cases. However, this fluid retention or edema can be very dangerous depending on where it occurs. Because having fluid retention in the legs or ankles is not the same as having it in organs such as the lung.
One of the most serious and dangerous situations that can occur in this sense is the presence of cerebral edema, which can even be the cause of death
Before talking about cerebral edema itself, it is necessary to first understand what we are referring to when we talk about the term edema. It is understood as such the existence of swelling or inflammation of soft tissues due to the accumulation of fluid in or between your cells, due to imbalances in the amount of interstitial fluid leaving or entering the cells.
This inflammation can have a wide variety of causes and can be found in almost all types of soft tissues in the body, and can have different repercussions depending on the type of tissue affected.
Cerebral edema: main symptoms
One of the locations where edema can occur, as well as one of the most dangerous, is in the brain tissue. In cerebral edema we find an increase and accumulation of fluid between the brain cells that generates inflammation with sufficient magnitude to cause clinical symptoms.
This inflammation is so serious in this case because the brain does not float in a vacuum, but rather it is surrounded by a bone structure that protects it but at the same time limits it: the skull. The accumulation of fluid can cause compression of the brain mass against its walls, potentially causing neurons to eventually die.
In addition, greatly increases the level of intracranial pressure by not maintaining the usual electrolyte balance, which can also alter and cause cellular degeneration. Finally, the compression can affect the blood vessels, preventing oxygen from reaching some of the brain regions and ending up suffocating.
Depending on the brain regions compressed, the symptoms can vary greatly. Dizziness, fatigue and weakness generally appear, as well as a possible alteration in the level of consciousness, headaches, gastrointestinal symptoms such as nausea and/or vomiting or perceptual alterations. Breathing may become faster and seizures may even occur.
Related to alterations of consciousness, In severe cases, the patient can go into a coma or even die if the nuclei responsible for maintaining heart and respiratory rhythm are compressed. In some cases it can lead to brain herniation or permanent loss of relevant functions.
In addition to these symptoms, the presence of cerebral edema can lead to death or the appearance of some type of physical, mental or sensory disability which can greatly alter the person’s usual functioning, whether temporarily or permanently.
Types of brain edema
There is no single type of cerebral edema, but we can find different typologies depending on where and why the imbalance and fluid accumulation occurs. And the liquid can accumulate both inside the cells and in the extracellular space.
1. Cytotoxic edema
In this type of edema, swelling occurs when fluid accumulates within the cells themselves, these having abnormally captured an excessive amount of interstitial fluid It is generally caused by a malfunction of the sodium/potassium pumps and the channels through which fluid enters and leaves the cells. We are faced with a problem of regulating cellular metabolism and maintaining homeostasis. The consumption of some toxic element may be one of its causes.
2. Vasogenic edema
It is considered as such that edema that occurs as a consequence of an increase in the permeability of the nervous system, due to the breakdown of the blood-brain barrier. Generally we find that blood plasma penetrates the parenchyma or extracellular space that surrounds nerve cells and accumulates in it. This is the most common type of cerebral edema. Tumors, strokes, and head injuries tend to be some of the most common causes.
Edema generated by the obstruction of the channels through which the cerebrospinal fluid circulates, causing the cerebral ventricles or areas near the blocked area to swell. Appears in hydrocephalus
Possible causes
There are a large number of possible causes for the existence of cerebral edema. Some of the most frequent are the following.
1. Traumatic brain injury
One of the causes that may be easier to identify is the one that has to do with the existence of a head trauma. This blow causes blood vessels to rupture, flooding the brain with blood. When trying to absorb excess fluid, the cells would become inflamed.
2. Stroke
The existence of a cerebral hemorrhage or blockage of the cerebrovascular system is one of the best known causes of cerebral edema. And these accidents would cause fluids to either directly extravasate inside the brain or cause nerve cells to die and rupture, causing fluid accumulation.
3. Viral or bacterial infections
Another possible cause of cerebral edema can be found in the existence of an infection. The cells are damaged and break down, their remains generating an imbalance in the level of brain fluid. Within this group of causes we find very different diseases, from meningitis to Reye’s syndrome
4. Tumors
The appearance of neoplasms, whether benign or malignant can generate compression of blood vessels or block the passage of cerebrospinal fluid, which may result in the appearance of fluid accumulation in some areas of the brain.
5. Hypoxia derived from altitude
This type of edema occurs in subjects such as climbers and scuba divers. The main cause is the existence of a sudden variation in atmospheric pressure due to rapid ascent: in the face of a lack of oxygen, the body tries to dilate the arteries and veins of the nervous system, but if this situation is prolonged or the change occurs very quickly, said dilation will generate homeostatic difficulties that will culminate in the accumulation of fluids in the brain.
6. Hyponatremia
Disorder that occurs due to the absence of a sufficient level of sodium in the blood, which the body tries to compensate by causing an increase in the entry of fluid into the cells.
Consumption of some toxic substance or poisoning It can generate alterations in the nervous system that cause imbalances in intra- or extracellular fluid levels.
Treatment
Treatment of cerebral edema is essential and requires rapid professional action in order to avoid death or the appearance of irreparable damage to the patient.
The first step that should be used is the elimination of fluid accumulation and the reduction of inflammation, making it essential to control vital signs at all times. The application of artificial breathing mechanisms may be necessary to maintain a constant and sufficient flow of oxygen.
In cases where the patient’s life is in danger, it is common to use immediate surgery to control the level of inflammation by draining the fluid, or resection of part of the skull to release and reduce intracranial pressure. Once the patient is stabilized, it is necessary to analyze what caused the problem in order to treat its causes.
Likewise, it has been proven that induction of controlled hyperventilation reduces the formation of cerebral edema. However, it must be very controlled, since depending on the extent and for how long it is carried out, it can have very harmful effects.
Both in this and other cases in which surgery is not used, the use of different drugs is common. For example, The application of corticosteroids is very common in order to reduce the level of intracranial pressure in those cases where the problem is not of cytotoxic or hemorrhagic origin. Osmotics and diuretics can also be used to facilitate the expulsion of fluids.
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