Cerebral ischemia: symptoms, causes and treatment

One of the most serious diseases of the circulatory system, due to the effects it can produce.

One of the most feared phenomena and brain problems worldwide is the appearance of a stroke or cerebrovascular accident, which is one of the most frequent causes of death worldwide.

The reason is the fact that their presence generates the death of part of the brain cells, something that can generate different more or less incapacitating consequences and even compromise survival depending on the areas that are damaged.

But the truth is that when we talk about stroke we are actually talking about two main types of stroke: we may be facing a cerebral hemorrhage or cerebral ischemia..

It is on this last type that we are going to focus throughout this article, in order to discuss what it is, for what reasons it can occur and what type of intervention can be carried out in those who have suffered from it.

What is cerebral ischemia?

It receives the name of cerebral ischemia to one of the big types of cerebrovascular accident that exist, which is characterized by the appearance of a degeneration or neuronal death in the brain derived from the existence of some type of blockage in some of the blood vessels that irrigate the brain..

This blockage causes the blood not to reach the nerve cells that the blood vessel should irrigate, so that the affected cells degenerate and die quickly because they do not receive sufficient oxygen and nutrients. Thus, technically we speak of ischemia when for some reason the supply of nutrients and oxygen that brain cells need to survive is interrupted.

Symptoms

Cerebral ischemia is an alteration that can generate a great variety and diversity of symptoms.The obstruction can occur in any of the blood vessels that irrigate any of the areas of the brain. Thus, the specific symptoms will depend largely on the affected area.

However, there are some symptoms that are common both in ischemia and in other strokes: the sudden onset of paralysis or numbness of a part of the face or half of the body, sudden speech disturbances (including aphasia in which the ability to understand and/or produce speech is lost) and sudden hypotonia or lack of muscle tone in a part of the body.

In addition to this, other types of disturbances may occur such as dizziness, headaches, hallucinations, personality changes, tremors and/or convulsions, blurred vision, or loss of abilities.blurred vision or loss of specific sensory abilities.

Between ischemia and cerebral hemorrhage, ischemia is much more common, and there are a large number of factors and situations in which a blockage of cerebral vessels may occur.

Its main types

Within ischemia we can also find different typologies, depending on how and why the blockage in question appears and even to what extent it affects more or less brain regions. Among the different types, the following stand out.

1. Thrombotic ischemia

This type of ischemia occurs when a blockage appears within the blood vessels of the brain, preventing the passage of blood. a blockage appears that impedes the passage of blood.. This obstruction is called thrombus, and usually comes from the presence of cholesterol plaques in the vein or artery or from the existence of a clot that forms within the cerebrovascular system itself.

2. Embolic ischemia

Embolic ischemia or embolism differs from the previous one because the element that causes the blockage of the cerebral blood vessel, in this case called embolus, arises in some part of the organism other than the brain and travels together with the bloodstream throughout the body until it finally reaches the cerebrovascular system, causing at some point a tamponade if it meets a smaller vessel than itself. This is what can occur with some blood clots, for example..

3. Transient ischemic attack

The transient ischemic attack is a type of cerebral ischemia in which, as in the rest, there is a sudden appearance of some element blocking the cerebral vessels, but which nevertheless the functioning of the organism itself manages to unblock it quickly by itself quickly (for example because the blood flow manages to push or fragment the embolus or thrombus).

In these cases the symptoms are usually of short duration and the subject can fully recover, although the fact that they have appeared means that the subject is at risk of the appearance of more severe symptoms.

4. Lacunar stroke

This is understood as a type of cerebral ischemia in which the affected blood vessel is an arteriole, i.e. one of the small branches of the arteries of the brain. small branches of the arteries that go deep into the different areas of the brain..

That the ischemia occurs at this level implies that the affected areas will generally be small and its effects will be less than in other types of stroke, but it can also have serious repercussions and even cause death depending on the region in which it occurs.

5. Focal cerebral ischemia

A type of ischemia in which the interruption of blood flow is called focal cerebral ischemia. is produced in a blood vessel that will irrigate a particular brain area, so that the effect at the neuronal level is specific to the particular area that is damaged or killed.The effect at the neuronal level is specific to the particular area that is damaged or dies.

6. Global cerebral ischemia

In this case, the ischemia does not occur in a specific vessel but occurs at a more globalized level, with all or almost all of the brain not receiving sufficient oxygen or nutrients. In this case the problem is global and has the potential to generate many more repercussions on the subject who suffers it.

7. Hemodynamic ischemia

In this little-known type of ischemia, there is no blockage as such, but there is an interruption in the delivery of oxygen or nutrients to the brain.. The cause of this type of stroke is the absence of a Blood Pressure deficit that leads the blood to circulate at the necessary speed to nourish the cells.

Causes

Technically, the presence of ischemia implies the existence of some type of blockage or difficulty in the arrival of blood with oxygen and nutrients to the brain cells. In this sense, the most common causes are usually blood clots or cholesterol and lipid plaques or cholesterol and lipid plaques that clog the arteries.. But beyond this, there are many possible causes that can lead to this type of stroke.

Among the many risk factors for its occurrence are the presence of high blood pressure, diabetes mellitus, cholesterol, previous brain lesions (for example due to scarring of a vascular lesion), heart problems (as in the case of hemodynamic cerebral ischemia), malformations, trauma (which can generate blood clots), lack of sufficient nutrients, tumors, smoking or use of certain drugs..

Affect on the subject's life

Cerebral ischemia generally has a great impact on the life of the patient, who may suffer important sequelae for some time or even for the rest of his or her life.

On a direct level, the patient may suffer from a wide range of problems resulting from the death of their tissues, which can range from aphasia to paralysis of part of the body, including tingling, cognitive difficulties (such as concentration or memory), sensory deficits, sleep problems, movement, sexuality or eating. Unfortunately, these problems cannot always be solved or compensated for, which can lead to the patient presenting different degrees of disability..

It should also be borne in mind that the social and occupational consequences of ischemia can have consequences: for example, if the patient suffers from ischemia-related aphasia, he or she will find it difficult to communicate effectively, which can be very frustrating for the subject and generate misunderstandings with the environment.

Finally, and beyond the direct consequences of ischemia, we cannot ignore the great emotional impact of suffering from this type of disorder.. The subject has experienced a life-threatening situation and it is not uncommon for anxious or depressive problems to appear, as well as a great fear of the possibility that it could happen again.

Treatment

In cases of cerebral ischemia, promptness in going to the medical center is essential and can save the life of the sufferer, as well as reduce the possible effects of cell destruction.

Once the problem has been identified, at the medical level it is possible to inject substances that allow the dissolution of clots or even use surgery to remove the clot (which can reach the cerebral arteries with procedures such as angioplasty from other parts of the body).

Once the problem has been treated and the blood supply has returned to normal, and after a period in which the patient remains under observation and in which it is possible that part of the area affected by the lack of risk (the so-called ischemic penumbra in which a cerebral area has been partly affected but has not died in its entirety, and which in some cases can partially or totally recover its functionality) may be reduced, it will be necessary to assess the neuropsychological state of the patient..

For this it will be necessary to assess its functionality in various areas, both motor and cognitive, in order to identify possible deficits and alterations that has caused the death of nerve cells. Once this is done, it will be necessary to elaborate an individualized treatment, in which depending on the case it may be necessary the use of occupational therapy, cognitive stimulation (in which aspects such as memory, executive functions or attention can be worked on), speech therapy and/or physiotherapy.

The aim is to carry out a neuropsychological rehabilitation of the patient, helping him/her to recover or compensate the affected functions.

Psychological therapy may also be useful to the affected patient, given that the sequelae of ischemia can be experienced with panic and suffering and cause (either directly as a consequence of the ischemia or indirectly by deriving from the perception of deficits) emotional alterations, anxiety, cognitive distortions and psychosocial adjustment problems.

Bibliographic references:

• Kuźma, Elżbieta; Lourida, Ilianna; Moore, Sarah F.; Levine, Deborah A.; Ukoumunne, Obioha C.; Llewellyn, David J. (2018-08). "Stroke and dementia risk: A systematic review and meta-analysis". Alzheimer's & Dementia. 0 (0).
• Lewis. S.L (2008). Medical-Surgical Nursing. Vascular disorder.