Hypoxia means oxygen starvation of the body as a whole or some organs. This condition appears due to insufficient oxygen in the inhaled gas mixture, in the blood, or when tissue respiration mechanisms are damaged. Changes that occur due to hypoxia are usually irreversible, so it is unacceptable to ignore this condition.

Hypoxia of the brain, heart, and kidneys is especially dangerous, since these systems are most sensitive to oxygen limitation.

What is hypoxia

In terms of the volume of blood flow serving the brain, the brain ranks first: 20% of the blood volume is spent on delivering oxygen and nutrients to the brain.

Brain tissue is extremely sensitive to a lack of oxygen: after 4 seconds of acute insufficiency, its functionality is impaired, after 8-12 seconds a person loses consciousness, after 30 seconds a coma sets in. In the absence of blood flow, the brain is able to function for no more than 4-5 minutes.

In practice, the time interval is somewhat longer, since acute hypoxia associated with the complete disappearance of blood flow is a rare phenomenon. Most often, a person is faced with a decrease in oxygen in the blood or disturbances in the absorption mechanism. The prognosis for life in this case is better, but the consequences of hypoxia range from treatable to severe irreversible.

Types of pathological condition

Hypoxia is not an independent disease. This is a condition that occurs when the volume of oxygen entering the cells decreases. Many different factors lead to this.

Types by etiology

In relation to external factors, the condition is classified as follows.

• Hypoxic - or exogenous. The condition develops due to a lack of oxygen in the inhaled air. The most trivial reason is a poorly ventilated room, ineffective ventilation in a completely enclosed room. Climbers encounter this kind of condition when climbing, since the volume of oxygen in the air decreases with altitude.
• Respiratory - or respiratory. Here, disturbances in the functioning of the respiratory tract are observed: pneumonia, exacerbation of bronchial asthma, dysfunction of the respiratory center, injuries, and so on. The reasons here are obvious and all efforts are aimed at treating the primary disease.
• Cardiovascular - or circulatory. The cause is changes in the composition of the blood that disrupt the normal flow of blood. This condition occurs with heart failure, narrowing of the working bed of the vessel due to thrombosis, atherosclerotic plaque, and so on. The consequences of hypoxia here are much more serious, including ischemic stroke of the brain.
• Hemic - associated with changes in blood composition. In the human body, oxygen molecules are transported in the form of a complex with hemoglobin. When the amount of hemoglobin or red blood cells decreases, oxygen remains unbound and, accordingly, cannot be delivered to the cell. The same picture is observed when the mechanism of binding hemoglobin with oxygen is destroyed.
• Tissue - in this case, the mechanism of oxygen utilization in the cell is disrupted, for example, when a fragment of the mitochondrial respiratory chain is blocked. Some poisons and medications have this effect.
• Overload is usually a temporary phenomenon associated with excessive stress on muscles, nerve tissue or organ.
• Technogenic - such hypoxia is formed due to the constant action of harmful, toxic substances in some industries.
• Mixed - any type of hypoxia, extended in time enough to cause tissue hypoxia. Here we need treatment of both the primary form and the secondary one.

Varieties by development time

Since hypoxia is a condition and not a disease, the rate of its formation can be very different.

• Lightning - for example, due to hemorrhage in the respiratory center or as a result of injury. If urgent assistance is not provided, this condition ends in death.
• Acute cerebral hypoxia develops over several hours. An example of this is cyanide poisoning, which blocks an enzyme in the respiratory chain. Help here is needed immediately, otherwise neither life nor health of a person is guaranteed. However, more time is allocated for treatment activities.
• Chronic brain hypoxia is not so life-threatening, but significantly reduces its quality. To compensate for the constant lack of oxygen, the body uses a variety of additional mechanisms. However, any of them are aimed only at maintaining vital functions, but not at all at fully restoring functions.

The most obvious compensation mechanisms include increasing the depth and frequency of inputs. Reserve alveoli begin to participate in breathing in order to maximize the working surface. Outwardly, this manifests itself as severe shortness of breath, which noticeably limits mobility. This increases the heart rate and blood pressure.

A redistribution of blood flow occurs: more blood is sent to the internal organs, and the periphery begins to experience secondary oxygen starvation. Lack of oxygen creates the need to increase the number of red blood cells, which significantly increases the risk of blood clots.

All this leads to rapid wear and damage to the cardiovascular and respiratory systems. Therefore, treatment of hypoxia should be started at the earliest stages. Later, coping with the painful condition and the consequences of its compensation is much more difficult.

Classification by localization

A lack of oxygen can be observed in a specific area of ​​the brain, or it can cover the entire organ.

The following types are considered:

• Scattered - a consequence of a general lack of oxygen in the blood. Causes low to moderate impairment. Curable with the most favorable prognosis.
• Central cerebral ischemia occurs when the blood supply to some part of the brain is disrupted. The cause, as a rule, is a narrowing of the vessel - an aneurysm, a blood clot. This condition is usually part of a larger medical condition.
• Global cerebral ischemia is a complete cessation of blood flow.
• Ischemic stroke - also caused by a sharp narrowing or obstruction of a blood vessel. Typically, a stroke affects several areas.

Symptoms of hypoxia

Like many other disorders in the central nervous system, hypoxia is accompanied by a deterioration in mental activity. The first signs of it are difficulties in solving problems, deterioration of short-term memory, that is, symptoms that can easily be attributed to fatigue.

At the next stage of acute hypoxia, the victim often experiences a state of euphoria. Excessive energy and excitement is accompanied by a clear lack of coordination and an unsteady gait.

Despite self-awareness from an objective point of view, cognitive functions deteriorate. Excitement is accompanied by pallor, but can sometimes cause redness of the skin. Profuse and unpleasant sweating, breathing and rapid heartbeat appear.

Excitement gives way to apathy, drowsiness, and is accompanied by dizziness. Vision decreases, spots appear before the eyes, then the patient loses consciousness. Fainting turns into a coma of varying depths.

Even at this stage, resuscitation care allows not only to save the patient’s life, but also to completely restore all brain functions. Restoration occurs in reverse order.

The cause of chronic lack of oxygen is diseases associated with narrowing of blood vessels, for example: cervical artery syndrome with osteochondrosis, hypertensive encephalopathy, etc.

Symptoms of brain hypoxia include the following disorders:

• dizziness, constant ringing in the ears;
• constant headache. The pain is relieved with vasodilator drugs, but immediately returns;
• impaired balance, coordination, speech;
• attacks of nausea and vomiting in the morning;
• deterioration of mental abilities - memory impairment, decreased performance;
• various sleep disorders are possible;
• There is a sharp change in mood, tearfulness and irritability prevail, depression and apathy develop.

Treatment of chronic hypoxia is inseparable from the treatment of the underlying disease. Only by eliminating the primary factor can success be achieved by restoring normal blood supply to the brain.

Diagnostics

Acute hypoxia has quite characteristic symptoms, which facilitates diagnosis. The signs of chronic disease coincide with most of the symptoms of disorders in the functioning of the central nervous system, and in most cases the cause of their appearance is a lack of oxygen.

The goal of diagnostics for hypoxia is to establish the primary cause of the pathological condition.

• Blood test - both general and gas. The former indicates the number of red blood cells, the latter allows you to accurately determine the partial pressure of oxygen and carbon dioxide in the blood.
• An encephalogram of the head provides information about the state of brain cells and the presence of poorly functioning areas.
• Rheovasography allows you to determine the condition of the blood vessels supplying the brain.
• Angiography - general or selective, provides a more complete picture of blood flow.
• Magnetic resonance imaging is the most informational method. Indispensable for suspected ischemia of certain areas of the brain.
• Capnography and CO-metry indicate the volume of carbon dioxide in exhaled air. In this way, disturbances in lung function are excluded or confirmed.

Treatment

Since the causes of the condition are varied, different methods are used to treat cerebral hypoxia.

• The exogenous form requires only restoration of the normal oxygen content in the blood, and the source is inhaled air. The treatment method is an oxygen pillow.
• In case of respiratory hypoxia, treatment is aimed at restoring the functions of the respiratory tract. For this purpose, respiratory analeptics, drugs that dilate the bronchi, and antihypoxanes are used.
• In the hemic form, drugs are used to help restore hematopoietic function. A common method is blood transfusion.
• To treat circulatory hypoxia, anticoagulants, vasodilators, nootropics, decongestants, angioprotectors, and so on are prescribed.
• The tissue form involves the use of antidotes if the root cause is poisoning. Any measures aimed at improving oxygen supply are acceptable: taking vitamins, hyperbaric oxygen therapy, and even walking in the fresh air.

Acute cerebral hypoxia is a fatal condition. Chronic significantly reduces the standard of living. Any form of the disease requires effective and immediate treatment.

Content

The state of the body in which cells and tissues are not saturated with oxygen is called hypoxia. It occurs in adults, children, and even in a child in the womb. This condition is considered pathological. It causes severe and sometimes irreversible changes in vital organs, including the heart, brain, central nervous system, kidneys and liver. Special pharmacological methods and agents help prevent complications. They are aimed at increasing the amount of oxygen delivered to the tissues and reducing their need for it.

What is hypoxia

Medicine defines this concept as a pathological condition in which there is a deficiency of oxygen in the body. It occurs when there is a violation of the utilization of this substance at the cellular level or a deficiency in the inhaled air. The term is derived from two Greek words – hypo and oxigenium, which are translated as “little” and “oxygen”. At the everyday level, hypoxia is oxygen starvation, because all cells of the body suffer from its lack.

Reasons

A common cause of oxygen starvation may be a lack of oxygen entering the body or a cessation of its absorption by body tissues. This is facilitated either by unfavorable external factors or certain diseases and conditions. If oxygen starvation develops as a result of a lack of oxygen in the inhaled air, then the form of pathology is called exogenous. Its reasons are:

• staying in wells, mines, submarines or other enclosed spaces that have no communication with the outside environment;
• smog in the city, severe gas pollution;
• poor ventilation;
• malfunction of anesthesia-respiratory equipment;
• being in a room where there are many people;
• thin atmosphere at altitude (pilot illness, mountain and altitude sickness).

If the pathology is the result of any disease or condition of the body, then it is called endogenous. The reasons for this type of oxygen starvation are:

• diseases of the respiratory system, such as asbestosis (deposition of asbestos dust in the lungs), pneumothorax, hemothorax (filling of the pleural cavity with air or blood), bronchospasm, bronchitis, pneumonia;
• the presence of foreign bodies in the bronchi, for example, after accidental ingestion;
• acquired or congenital heart defects;
• fractures and displacements of the chest bones;
• diseases or pathologies of the heart, such as heart attack, heart failure, pericardial obliteration, cardiosclerosis (replacement of the heart muscle with connective tissue);
• injuries, tumors and other brain diseases that damage the respiratory center of the central nervous system;
• venous hyperemia (plethora);
• congestion in the system of the superior or inferior vena cava;
• acute blood loss;
• asphyxia (suffocation) of any nature;
• a sharp narrowing of blood vessels in various organs.

Intrauterine fetal hypoxia

For an unborn baby, oxygen deficiency is very dangerous. It causes serious complications: in the early stages of pregnancy - slowdown or pathology of fetal development, in the late stage - damage to the central nervous system. Oxygen starvation of a child can be caused by some systemic diseases of a pregnant woman, including:

• pathologies of the cardiovascular system, which lead to vascular spasms and deterioration of blood supply to the fetus;
• diseases of internal organs, such as pyelonephritis and inflammation of the urinary system;
• iron deficiency anemia, which interferes with the supply of oxygen to tissues;
• chronic diseases of the respiratory organs, for example, bronchial asthma or asthmatic bronchitis;
• disturbances in the functioning of the endocrine system.

Hypoxia during pregnancy is often associated with a woman’s bad habits. A pregnant woman is strictly prohibited from smoking and drinking alcohol. All toxins enter the baby's bloodstream and lead to serious complications. Fetal hypoxia is also associated with other disorders:

• abnormalities in the development of the placenta or umbilical cord;
• post-term pregnancy;
• increased uterine tone;
• premature placental abruption;
• infection of the fetus;
• incompatibility of fetal blood with maternal blood according to the Rh factor;
• prolonged compression of the head in the birth canal;
• entwining the umbilical cord around the neck;
• entry into the respiratory tract of mucus or amniotic fluid.

Signs

Hypoxia in a person can be determined by certain signs. There are symptoms common to all types of oxygen deprivation. They appear when the brain absorbs less than its fair share of oxygen. With this disorder, the following symptoms are observed:

1. Nervous system inhibition. Has a pronounced character. The patient complains of nausea, headache and dizziness. Sometimes visual disturbances and even loss of consciousness are observed.
2. Increased excitability. The person ceases to control speech and movements and feels in a state of euphoria.
3. Change in skin tone. The person's face begins to turn pale and then turns blue or red. Cold sweat indicates that the brain is trying to cope with the condition on its own.
4. Brain damage. Develops in severe oxygen deprivation and can lead to cerebral edema. This condition is accompanied by the loss of all reflexes and disruption of the functioning and structure of organs. The patient falls into a coma.

Acute hypoxia

The symptoms of oxygen deficiency are somewhat different for acute and chronic forms. In the case of lightning oxygen starvation, not a single symptom has time to appear, because death occurs within 2-3 minutes. This condition is very dangerous and requires emergency help. The acute form of hypoxia develops within 2-3 hours and is characterized by the following symptoms:

• decrease in heart rate;
• change in total blood volume;
• breathing becomes irregular;
• coma and agony followed by death if hypoxia was not eliminated at the initial stage.

Chronic

This form of hypoxia is manifested by hypoxic syndrome. In this case, symptoms from the central nervous system are observed. The brain is sensitive to oxygen starvation. Foci of hemorrhage, necrosis and other signs of cell destruction develop in the tissues of the organ. At an early stage, these changes cause a person to experience a state of euphoria and motor restlessness.

As hypoxia progresses, the cerebral cortex is depressed. Symptoms resemble those of alcohol intoxication. The patient experiences the following sensations:

• convulsions;
• drowsiness;
• nausea, vomiting;
• involuntary passage of urine and feces;
• disturbance of consciousness;
• tinnitus;
• lethargy;
• headache;
• dizziness;
• impaired coordination of movements;
• lethargy.

With convulsions, the development of opisthotonus is possible - a condition in which a person arches, his neck and back muscles straighten, his head throws back, and his arms bend at the elbows. The pose resembles a “bridge” figure. In addition to signs of depression of the cerebral cortex, during hypoxia the following are observed:

• pain in the heart area;
• a sharp decrease in vascular tone;
• tachycardia;
• low body temperature;
• dyspnea;
• depression;
• drop in blood pressure;
• cyanosis - blueness of the skin;
• irregular breathing;
• delirium – “delirium tremens”;
• Korsakov's syndrome - loss of orientation, amnesia, replacement of real events with fictitious ones.

Types of hypoxia

According to the type of prevalence of oxygen starvation, hypoxia can be general or local. The broadest classification divides this condition into types depending on the etiology, i.e. reasons for occurrence. So, hypoxia happens:

1. Exogenous. Also called hypoxic hypoxia, which is caused by environmental factors. Pathology develops due to insufficient oxygen supply to the body.
2. Endogenous. Associated with third-party diseases or disorders.

Endogenous hypoxia is further divided into several subtypes depending on the etiology. Each type has a specific cause:

1. Respiratory (pulmonary, respiratory). It develops due to obstructions in the area of ​​the pulmonary alveoli, which prevents hemoglobin from immediately contacting oxygen.
2. Circulatory. Occurs due to a disorder of circulatory processes. According to the mechanism of development, it is divided into ischemic and stagnant.
3. Hemic. It is observed with a rapid decrease in hemoglobin. Hemic hypoxia can be anemic or caused by a deterioration in the quality of hemoglobin.
4. Fabric. Associated with the cessation of oxygen absorption due to suppression of enzyme activity. Tissue hypoxia is observed with radiation, poisoning with toxic substances of microbes, carbon monoxide or salts of heavy metals.
5. Substrate. Against the background of normal oxygen transportation, there is a lack of nutrients. More often observed with diabetes mellitus or prolonged fasting.
6. Reloading. Occurs after heavy physical exertion.
7. Mixed. It is the most serious type and is observed in cases of serious life-threatening pathologies, for example, coma or poisoning.

The following classification divides hypoxia into types, taking into account the rate of development of oxygen starvation. The most dangerous is the one that manifests itself very quickly, because it often leads to death. In general, there are the following types of hypoxia:

• chronic – lasts from several weeks to a couple of years;
• subacute – develops within 5 hours;
• acute – lasts no more than 2 hours;
• lightning fast - lasts 2-3 minutes.

Degrees

Hypoxia is classified according to the severity of its symptoms and the severity of oxygen deficiency. Taking these factors into account, oxygen deficiency has the following degrees:

1. Critical. Hypoxic syndrome leads to coma or shock and can result in agony and death.
2. Heavy. The lack of oxygen is severe, and the risk of developing a coma is high.
3. Moderate. Clinical signs of hypoxia appear at rest.
4. Easy. Oxygen starvation occurs only during physical activity.

Consequences

Oxygen deficiency affects the functioning of all organs and systems. The consequences depend on the period in which the pathology was eliminated and how long it lasted. If the compensatory mechanisms have not yet been exhausted, and the oxygen deficiency has been eliminated, then no negative consequences will arise. When the pathology appears during the period of decompensation, complications are determined by the duration of oxygen starvation.

The brain suffers more from this condition, because without oxygen it can only withstand 3-4 minutes. The cells may then die. The liver, kidneys and heart are kept for about 30-40 minutes. The main consequences of oxygen deficiency:

• depletion of adaptation reserves;
• weakening of antitumor protection;
• decreased immunity;
• deterioration of memory and reaction speed;
• neuropsychiatric syndrome;
• psychosis;
• dementia;
• parkinsonism (shaking palsy);
• exercise intolerance;
• fatty degeneration of muscle cells, myocardium, and liver.

Consequences for the child

Oxygen deficiency is one of the common causes of not only fetal mortality, but also the appearance of developmental defects. The consequences depend on the trimester of pregnancy and the degree of oxygen deficiency:

1. First trimester. During this period, the laying of organs occurs, therefore, due to oxygen deficiency, a slowdown in the development of the embryo and the formation of anomalies are possible.
2. Second trimester. At this stage, problems arise with the baby’s adaptation and pathologies of the central nervous system. In the chronic form, the death of the child is possible.
3. Third trimester. Lack of oxygen provokes developmental delays during pregnancy. Serious damage to the baby's nervous system is also possible. During childbirth, oxygen deprivation causes asphyxia.

Consequences of fetal hypoxia in a child after birth

Experiencing oxygen deprivation after the birth of a baby seriously affects his health. The child becomes restless, easily excitable, and suffers from high muscle tone. The latter is expressed in frequent twitching of the legs or arms, convulsions, and trembling of the chin. Other symptoms include lethargy, frequent regurgitation and reluctance to latch on to the breast. A list of more serious consequences includes:

• stillbirth;
• death in the early postpartum period;
• impairment or delay of psychomotor and intellectual development;
• damage to blood vessels and heart;
• diseases of the nervous system;
• problems with the urinary organs;
• severe eye diseases.

How to determine fetal hypoxia

You can suspect a lack of oxygen in a baby based on high motor activity. It is a reflex by which the child tries to restore normal blood flow and increase blood supply. A pregnant woman feels the following:

• violent movement of the baby;
• sudden strong shocks that cause pain and discomfort;
• with increasing oxygen deficiency, a gradual weakening of the tremors, which may disappear completely.

At the last sign, a woman should be wary. In general, fetal activity in the antenatal clinic is observed from the 28th week of pregnancy. When determining intrauterine oxygen deficiency, doctors use the following methods:

1. Listening to heart sounds. For this purpose, a stethoscope is used - a special obstetric device. It allows you to evaluate the tone, rhythm and heart rate, and notice extraneous noise.
2. Cardiotocography. It is a recording of the heart rhythm on paper using a special ultrasonic sensor.
3. Doppler. It consists of studying abnormalities in blood flow between the fetus and the woman. The method helps determine the severity of oxygen starvation.

In addition to the basic methods, laboratory blood tests are used to determine hormone levels and biochemical composition. To confirm hypoxia, amniotic fluid is examined for the presence of original feces - meconium. It indicates relaxation of the baby's rectal muscles due to lack of oxygen. This diagnostic method plays an important role in the progression of labor. The entire birth process will depend on it.

Treatment

In most cases, a mixed form of oxygen deficiency is noted. For this reason, the treatment approach must be comprehensive. To maintain the supply of oxygen to cells, hyperbaric oxygenation is used - a procedure for pumping this gas into the lungs under pressure. It provides:

• dissolution of oxygen directly in the blood without binding to red blood cells;
• delivery of oxygen to all tissues and organs;
• dilation of blood vessels in the heart and brain;
• organs work at full capacity.

For the circulatory form, taking heart medications and medications that increase blood pressure is indicated. In case of blood loss incompatible with life, a blood transfusion is required. Hemic hypoxia, in addition to hyperbaric oxygen therapy, is treated using the following procedures:

• blood or red blood cell transfusions;
• administration of drugs that perform the functions of enzymes;
• plasmapheresis and hemosorption (blood purification);
• administration of oxygen carriers, glucose or steroid hormones.

During pregnancy, treatment of oxygen deficiency is aimed at normalizing blood circulation in the placenta. This helps ensure that nutrients and oxygen reach the fetus. Preparations and methods used:

• relax the myometrium;
• improve rheological blood parameters;
• dilate the uteroplacental vessels;
• stimulate metabolism in the placenta and myometrium.

Every day a woman needs to breathe a mixture of oxygen and air. Medicines are prescribed only by a doctor. A specialist may prescribe the following medications:

• Szigetin;
• Trental;
• Methionine;
• Heparin;
• Chime;
• Vitamins E and C;
• glutamic acid;
• Haloscarbine;
• Lipostabil.

In case of oxygen starvation at 28-32 weeks, emergency delivery is necessary. The same applies to the deterioration of biochemical blood parameters, the appearance of meconium in the amniotic fluid, and oligohydramnios. As preparation for obstetric or surgical resolution of childbirth, the following is used:

• breathing with humidified oxygen;
• intravenous administration of glucose;
• introduction of Sigetin, Cocarboxylase and ascorbic acid, Euphyllin.

If oxygen deficiency is suspected at birth, the baby is immediately provided with medical assistance. Mucus and fluid are removed from the respiratory tract, the child is warmed, and, if necessary, resuscitation measures are carried out to ensure that the threat to life is eliminated. When the newborn's condition has stabilized, he is placed in a pressure chamber. There he obtains nutrient solutions. As you grow older, excitability, convulsions, twitching of arms and legs gradually stop, but at 5-6 months a relapse of the pathology is possible.

Prevention of hypoxia

Measures to prevent oxygen starvation are aimed at preventing conditions that lead to this. A person should lead an active lifestyle, walk more often, play sports and eat right. Chronic diseases need to be treated on time. When working in stuffy rooms, they must be regularly ventilated. Prevention during pregnancy is as follows:

• drinking oxygen cocktails;
• swimming;
• singing (develops proper breathing);
• doing normal household chores (a regimen with minor physical activity supplies the muscles with oxygen);
• ensuring a calm environment;
• walks in the fresh air;
• full healthy sleep;
• a balanced diet with foods rich in potassium, iron, iodine;
• tracking fetal movements (normally, the baby moves about 10 times a day);
• regular visits to the doctor.

Video

How to give oxygen to a baby? | Prevention of fetal hypoxia in pregnant women | "Before and After Childbirth" How to reduce an adult's temperature

Brain hypoxia is a persistent pathological change in tissues that develops due to an acute lack of oxygen. This condition can occur in any department and organ. The most dangerous phenomenon is considered to be prolonged hypoxia in the brain, which often causes deaths in medical practice.

What is hypoxia? In simple terms, this is the name for a condition caused by oxygen starvation. The human central nervous system has a rich blood supply, due to which the brain constantly receives essential nutrients (for example, glucose) and oxygen. Brain structures are extremely sensitive to the lack of these elements.

According to the classification, the following types of cerebral hypoxia are distinguished:

1. Acute(the prerequisites for the development of the pathological condition are massive blood loss, poisoning and cardiovascular failure, as a result of which the number of red blood cells and transportable oxygen decreases).
2. Subacute.
3. Chronic brain hypoxia (occurs with chronic heart failure, developmental defects, when the force of contraction becomes insufficient to transport oxygen and blood to the brain).
4. Lightning fast(develops rapidly, does not exceed a couple of minutes in duration).

With prolonged hypoxia, cell functioning in any tissue is disrupted and cells die.

What are the causes of the pathology?

The clinical picture of cerebral hypoxia may differ depending on the cause that caused this pathology. It is especially important to take this into account when prescribing appropriate treatment.

What are the causes of brain hypoxia?

1. Circulatory occurs after any pathologies in the cardiovascular system. Impaired blood circulation through the cerebral vessels develops, and hypoxic-ischemic changes in the brain are observed.
2. Exogenous. The causes of this type of hypoxia are considered to be low oxygen content in the surrounding air (with a significant rise to the mountains, in a stuffy room).
3. Fabric. In case of disruption of adequate functioning of the body and developing metabolic pathologies. Dangerous metabolites appear in the blood, which have an additional negative effect on brain tissue.
4. In diseases of the respiratory system, the delivery of oxygen not only to the cerebral tissues, but to other tissues of the body is significantly impaired.
5. With anemia - a decrease in the amount of hemoglobin and red blood cells - the ability of blood cells to transport oxygen decreases.

Clinical manifestations of brain hypoxia

With brain hypoxia, symptoms arise that are quite characteristic of this pathology. Manifestations vary depending on the form of developing pathology and the reasons contributing to its appearance. The attending physician and the patient first of all pay attention to the following signs:

1. A state of euphoria and increased motor excitability are present if cerebral hypoxia is moderately developed and the pathological processes are reversible.
2. Headache, vomiting, and dizziness are reliable symptoms of insufficient oxygen supply to the brain.
3. The skin of a person with hypoxia initially turns pale, and with prolonged oxygen starvation begins to turn blue.
4. Cold clammy sweat, trembling.
5. At the very end, a phase develops that is the complete opposite of the first: inhibition of motor and emotional activity. This is a symptom of deep damage to the structures of the nervous system.

Also, most patients experience severe visual disturbances, tactile sensitivity in the extremities, absence or reduction of unconditioned reflexes, fainting often occurs, often turning into a deep coma. In children (especially the first years of life) in the vast majority of cases, cerebral edema develops.

Complications of oxygen starvation

Severe cerebral hypoxia of the brain is one of those conditions that require immediate medical attention. The general prognosis depends on many factors, which include: the severity of the pathology, its causes, the presence of concomitant diseases, as well as the time that has passed since the onset of acute hypoxia. If the patient did not lose consciousness or fall into a comatose state, then the chances of successful rehabilitation after the acute period subsides are very high.

If a coma develops, atrophic changes in the brain structures rapidly increase, which can ultimately lead to pathologies of the nervous system. The life expectancy of a patient in a coma due to hypoxia usually does not exceed one year.

It is necessary to take into account the fact that oxygen starvation contributes to the development of serious complications: thrombosis, the addition of infectious diseases.

The patient's condition after hypoxia

Tissues subjected to oxygen starvation do not fully restore their functions for a long time. However, with proper therapy, this indicator can be slightly improved. The function of dead brain cells can be taken over by neighboring structures, so partial restoration is possible.

The prognosis for the development of the disorder and the rehabilitation of a person depend on the severity of the pathology. If brain hypoxia is complicated by a coma or clinical death, then this will inevitably lead to disturbances in the central nervous system. Accordingly, conditioned and unconditioned reflexes, coordination, auditory, visual and taste analyzers will suffer. Recovery for such patients can range from one year to several years. Not all changes that occur will be reversible.

If cerebral hypoxia develops without complications, then rehabilitation can take up to one month, especially when there are no complications in the form of mental disorders and motor activity.

Brain hypoxia is difficult to treat, despite a wide range of medications for the treatment of pathologies. Complete recovery of the patient is quite rare.

The sooner therapy is started, the greater the chances of a good prognosis for the disease (the cells are less hungry, have not yet lost their ability to recover, and the focus of hypoxia is small).

What examination methods allow one to suspect hypoxia?

Outside a hospital setting, hypoxia can only be suspected indirectly by the characteristic clinical signs of hypoxia described above. And already in the hospital a whole range of examinations is carried out to clarify the diagnosis. The most common and reliable methods are:

1. Ultrasound echography helps to establish the location and even the cause of oxygen starvation at an early stage of the development of the pathology. The affected brain structure and the volume of dead nerve cells are indicated. This examination method is especially indicated for young children. In adults, ultrasound echography even helps to provide an approximate prognosis for the development of pathological changes.
2. Pulse oximetry measures the oxygen saturation of the blood as a percentage. A decrease in this indicator indicates acutely developing disorders in the human body. The diagnostic method is extremely accessible and is used everywhere.
3. Clinical blood tests: ions and other indicators of acid-base balance are especially important.
4. Computed tomography, MRI is a very important diagnostic method, which, unfortunately, is not available in every hospital. A survey CT or MRI shows areas of cerebral edema, areas of nerve cell death, and healthy areas receiving the necessary oxygen.

For proper and qualified assistance to a patient who is suspected of developing or established cerebral hypoxia, it is necessary to first conduct a full range of important examinations. Only after specifying the localization and degree of hypoxic damage to brain structures should one begin adequate treatment of the pathology.

Drug treatment of oxygen starvation

The main goal of therapeutic measures is to restore adequate supply of necessary oxygen to the brain. If there are concomitant diseases, they are also corrected as far as possible. It is important to remember that the earlier treatment is started, the more promising the person’s future rehabilitation is.

Medications include iron supplements and multivitamins. The medicine improves blood circulation and normalizes metabolism in tissues. In most cases, administration occurs intravenously or intramuscularly, and not in the form of tablets.

In severe forms, brain hypoxia must be treated with antihypoxants, respiratory analeptics, and drugs that dilate the bronchi. In case of critical condition, transfusion of whole blood, plasma, and use of mechanical ventilation are advisable.

First emergency and medical aid for acute cerebral hypoxia

Treatment of cerebral hypoxia in a patient is as follows:

1. It is advisable (if possible) to eliminate the probable cause that led to the development of oxygen starvation.
2. It is imperative to ensure a flow of fresh air (take the victim outside, open the windows in the room, etc.)
3. The victim must be freed from clothing that restricts breathing.
4. You should call an ambulance immediately.

In the future, it is necessary to use an oxygen mask with humidified oxygen.

Prevention of pathology

There are many methods that are useful to use to prevent the development of brain damage. These include breathing exercises. It promotes the stability of central nervous structures during oxygen starvation, and is also useful for restoring normal function of systems.

The most popular are:

1. Eastern techniques.
2. The principle of oxygen starvation.
3. Bodyflex.
4. Methodology according to Strelnikova.

However, before using the methods, you should consult with your doctor, since the selection of the most optimal method for a person should be under the direct supervision of a medical professional. The use of breathing exercises does not replace taking medications, but only complements them. Only by acting together can they help avoid possible complications.

Conclusion

Brain hypoxia is a rather serious pathology that requires immediate treatment. With timely diagnosis and treatment, it is possible to avoid numerous complications and reduce rehabilitation time several times. However, to prevent hypoxia, it is recommended to use breathing techniques.

Shoshina Vera Nikolaevna

Therapist, education: Northern Medical University. Work experience 10 years.

Articles written

Without oxygen, a person’s life is at risk, even if he has been gone for several minutes. Brain hypoxia indicates an insufficient supply of this useful substance to the body or that the order of removal of carbon dioxide from the blood is disrupted.

The lack of oxygen in the brain is dangerous due to the irreversible processes that occur. If the process of providing the body with oxygen is continuous, nothing threatens a person, but a failure in the respiratory system or transport elements of the blood flow - and the brain is the first to be affected.

Brain hypoxia is a condition of the body that can already lead to other pathologies. A few seconds are enough for all internal organs and systems to stop functioning. That is why brain hypoxia is called critical for any living creature.

Already at the 15th second, brain activity stops, leading to a coma. And each subsequent second provokes irreversible processes.

That is why, if acute hypoxia occurs far from a medical facility where there are doctors and the necessary equipment for resuscitation, a person’s chances of survival are extremely low. The survival rate in such cases does not exceed 4-5%.

Important! 3-4 minutes of oxygen starvation of the brain is enough for a person to die. In infants and young children this period is even shorter.

Hypoxia is dangerous during pregnancy and childbirth, because the life of the child and/or fetus is at risk: he may die or suffer complications leading to disability. Doctors identify the following reasons that provoke this condition in newborns:

1. The woman in labor has been diagnosed with serious and severe health problems, such as intoxication, leukemia, heart disease, etc.
2. There is a problem with the umbilical cord, which arises due to its defects, incorrect presentation of the fetus, post-term pregnancy, during prolonged or rapid labor.
3. Fetal development defect, heart defect, complications of infectious disease, intracranial injury and conflict of Rh factor of mother and child.
4. Asphyxia due to obstruction of the airways.

Important! A prolonged lack of oxygen in the fetus leads to irritation of the respiratory centers, because of this the child begins to breathe mucus, blood, and amniotic fluid. At the first breath, pneumothorax will occur, leading to the death of the child.

Species

Brain hypoxia is divided into types according to etiology, time of development and localization.

By etiology

If we take into account external factors, cerebral hypoxia can be divided into the following types:

1. Hypoxic, when there is a lack of oxygen directly in the air. Most often this occurs due to poor ventilation of the premises, lack of ventilation in completely enclosed rooms. Climbers experience symptoms of brain hypoxia, because the higher you go, the less oxygen in the air.
2. Respiratory, when there is a malfunction of the respiratory system due to diseases or dysfunctions of the respiratory center.
3. Cardiovascular, caused by changes in the composition of the blood, which interferes with its normal flow: heart failure, narrowed working channels along,. Such hypoxia can lead to ischemic stroke of the brain.
4. Hemic, associated with changes in the composition of the blood. Oxygen is transported throughout the body by hemoglobin molecules. And if there is a deficiency in it, then oxygen will remain unbound and will not be able to enter the cells.
5. Tissue, when the body cannot utilize carbon dioxide from cells. Most often it occurs due to blockage of a fragment of the mitochondrial respiratory chain, provoked by poison or a number of drugs.
6. Overload, which is a temporary phenomenon due to excessive load on muscle, nervous tissue or the organ itself.
7. Man-made, caused by harmful substances in production, etc.
8. Mixed, any hypoxia that led to a tissue type of pathology.

By exposure time

Due to the fact that hypoxia is not a disease, but a condition, the speed of its development is extremely important. There are 3 types of it:

1. Lightning fast, developing rapidly, for example, with injury or hemorrhage in the respiratory center. It doesn’t matter whether it happened to an adult or a child, without urgent medical attention the patient will die.
2. Acute when it takes a couple of hours to develop, which often happens with cyanide poisoning, which blocks enzymes of the respiratory chain. The time it takes to provide emergency care is in minutes, because the faster it happens, the higher the chance of preserving the health and life of the patient.
3. Chronic, not threatening the patient’s life, but significantly worsening its quality. The body uses all mechanisms to independently saturate the brain with oxygen, only to maintain its vital functions, but there will be no full restoration of functions.

By localization

Doctors divide the localization of brain hypoxia into 4 main types:

1. Dissipated, when there is a general lack of oxygen in the blood, which leads to disorders of low and moderate severity. At the same time, it has the most favorable prognosis for the patient.
2. Central, cerebral, ischemic attack, when the blood supply to a separate area of ​​the brain is disrupted due to thrombosis due to a more extensive pathology.
3. A global, cerebral, ischemic attack in which blood does not completely flow to the brain.
4. Ischemic stroke, caused by rapid narrowing and/or obstruction of blood flow. With it, several areas will be affected at once.

Symptoms of oxygen starvation of the brain

The clinical picture of a lack of oxygen in the brain is special, and its effect is difficult not to notice:

• increased excitability, when it is difficult to control facial expressions, actions, behavior;
• the head and whole body are covered with cold sweat, so the body copes with hypoxia on its own;
• the skin becomes an unnatural color, which immediately attracts the attention of strangers; most often the face becomes red or pale with a bluish tint;
• the central nervous system will be inhibited and brain structures damaged, resulting in slurred speech, hearing loss, blurred vision, fainting, etc.
• signs of loss of both unconditioned and conditioned reflexes due to swelling of the brain, which this condition led to.

The higher a person's sensitivity to hypoxic damage, the greater the chance that he will fall into a coma. When the main control center of the body is turned off, the heart, blood flow, and all vital functions of the body can stop. This is why even a short-term attack is so dangerous.

Human defense mechanisms during hypoxia

Even a premature baby will fight for his life at the level of unconditioned reflexes. During hypoxia, a number of protective mechanisms are triggered in humans:

• increase in breathing rate, it becomes deep, and subsequently intermittent, rare, superficial;
• an increase in the frequency and contractile force of the heart, an increase in blood pressure so that more oxygen enters the body tissues;
• hunger leads to the extraction of blood reserves from the liver and spleen so that transportation is carried out faster;
• all functional organs slow down their work to optimize the process;
• alternative energy production through the breakdown of carbohydrates according to the principle of anaerobic glycolysis, which provokes acidosis.

Despite the abundance of mechanisms, they will ultimately lead to the death of the body, since failures that occur when they are turned on are incompatible with life. After the blood supply is taken from the organs, they will gradually fade away and it is not always possible to restore their functionality even with the help of doctors.

Therefore, it is important to prevent the body from reaching this stage, which is only possible if resuscitation measures are started on time.

Diagnostics

Even at home, you can diagnose an attack of acute hypoxia due to the characteristic clinical picture. But the chronic type of hypoxia is similar to a malfunction in the functioning of the central nervous system and often occurs due to it. Therefore, the doctor will prescribe measures to determine the root cause of the condition, be it cervical osteochondrosis or a tumor. Alcoholism also leads to chronic hypoxia.

The doctor will prescribe:

• blood for general and gas analysis;
• rheovasography;
• angiography;
• capnography;
• CO-metrics.

In severe cases, all of the above checks can be carried out, but most often this is a set of 3-4 measures, which are sufficient to make a diagnosis.

Emergency care and treatment

All measures should be aimed at restoring breathing, gas exchange and stabilizing the patient, and only then at rehabilitation. And traditional methods are not suitable here. At the same time, it is necessary to determine the cause of the condition and eliminate it so that the vital functions of the body are not at risk.

For example, if a teenager becomes ill on a stuffy bus, he needs to be taken out into fresh air or given an oxygen bag. To speed up the process, you will need an injection of a bronchodilator drug. If the cause is a hypertensive crisis, Riboxin can be used. But each case is individual.

Important! Emergency assistance - calling an ambulance and providing resuscitation measures required in such a situation.

General drug therapy is based on the following drugs:

• normalizing the functioning of the vascular system;
• to improve blood supply;
• blood thinners;
• eliminating atherosclerotic vascular lesions;
• to relieve pain, nausea;
• strengthening the body.

In newborns

The birth of a child is already a difficult process, but if the baby has difficulty breathing, the doctor will clear the passages of mucus, residual amniotic fluid and introduce surfactants to eliminate their swelling. Most often, artificial respiration is indispensable. The newborn is placed in a special chamber with increased oxygen content and pressure to quickly make up for the resulting deficiency.

In adults

After emergency measures and stabilization of the patient, he needs to take all measures to change his lifestyle if they cause hypoxia. Thus, smokers, if they cannot completely give up the bad habit, should spend less time indoors and spend more time in the fresh air and perform special breathing exercises.

If the cause is poison, then doctors will introduce antidotes in order to neutralize them in a timely manner and bring the person back to normal. Each specific case is treated differently. And prevention is the same for all cases - a healthy lifestyle and monitoring your health.

Consequences

During hypoxia, not only the cerebral cortex suffers, but also all its structures. And the consequences will depend on how quickly the attack occurred. Unfortunately, instantaneous, subacute and acute types of hypoxia are fatal, except in cases where resuscitation care was provided immediately after the onset of the attack. Chronic oxygen deficiency gradually affects brain tissue, leading to:

• vomiting and nausea;
• vertigo;
• confusion and loss of consciousness;
• problems with speech, hearing and vision;
• systematic pain in the head.

Provided that during a hypoxic attack, timely assistance is provided by a team of highly qualified doctors, appropriate treatment and preventive measures are carried out, there is a good chance of complete restoration of brain functions.

But if we are talking about chronic hypoxia, which has not been treated for a long time, then serious consequences cannot be avoided.

Even if therapy is started, it is impossible to restore the brain to its previous state, and the person will suffer from the consequences of oxygen starvation.

Hypoxia (ancient Greek ὑπό - under, below and lat. oxygenium - oxygen) is a state of oxygen starvation of both the entire body as a whole and individual organs and tissues, caused by various factors: alcohol consumption, breath holding, painful conditions, small oxygen content in the atmosphere, death of the body. Due to hypoxia, irreversible changes develop in vital organs. The most sensitive to oxygen deficiency are the central nervous system, heart muscle, kidney tissue, and liver. It can cause an inexplicable feeling of euphoria, leading to dizziness and low muscle tone.

Due to the fact that oxygen stops flowing to the brain cells, hypoxia begins, that is, oxygen starvation (oxygen deficiency).

The main causes of hypoxia in the body

Hypoxic hypoxia is a decrease in the partial pressure of oxygen in the inhaled air.

Hemic hypoxia is a decrease in hemoglobin content or blockade of its oxygen transport function.

Circulatory hypoxia is a general or local disturbance of blood circulation.

Blockade of mitochondrial respiratory chain enzymes (eg by cyanide), which involves the function of oxygen as an electron acceptor and therefore the formation of ATP.

Brain hypoxia can be part of general and local hypoxia of the body. Thrombosis of the artery that brings blood to the brain tissue. A feature of local hypoxia is the disruption of the delivery of not only oxygen, but also nutrients, as well as the removal of metabolic end products. Altitude sickness, blood loss, anemia, etc.

Oxygen regime of the brain

The brain, which makes up no more than 2% of body weight, consumes 20 - 25% of the oxygen entering the body. 02 consumption by the whole brain ~ 33 ml 02/(kg-min). In this case, gray matter consumes 02 5 times more than white matter. In the cerebral cortex, neurons consume 70% and glial cells consume 30% of oxygen.

The perikaryon of a neuron (its trophic center), occupying 5% of the cell volume, consumes 25% 02, synaptic endings (-15% of the cell volume) - 10% 02. The brain extracts 67 ± 8 ml 02 from 1 liter of flowing blood and secretes 66 ± 8 ml CO2.

When blood pressure and cerebral blood flow decrease by 2 times, the consumption of 0 2 by the brain does not significantly decrease, which indicates powerful mechanisms for compensating its hypoxia. Decrease in cerebral blood flow by 3 times, and P0 2 in the venous blood of the brain to 20 mm Hg. Art. is a critical zone, accompanied by loss of consciousness and fading of the EEG (development of agony). The consumption of 0 2 by the brain is reduced by 2 times. Decrease in cerebral blood flow by 4 times, P0 2 in venous blood to 10 mm Hg. Art., and consumption of 0 2 by more than 80% represents the “lethal threshold” at which the EEG disappears and irreversible changes develop.

Energy processes in the brain

are among the most oxygen dependent. The human brain spends on average 20% of the body's energy budget. The energy costs for impulse activity (generation of action potentials) under conditions of physiological rest are equal, according to various authors, from 15 to 50% of the generated ATP, for the processes of processing and storing information - approximately 15%, for the transport of glucose through the blood-brain barrier - about 10% , the rest of the energy is used for biosynthesis and axonal transport of substances. The main (almost the only) substance used by the brain to form ATP is glucose. No organ consumes blood glucose in such quantities as the brain or depends to such an acute extent on glucose oxidation to maintain its functional activity. However, the content of glucose, both free and stored in glycogen, in the brain tissue is small (no more than 4.5 mmol/kg) and can be completely used within 5 - 7 minutes, which makes the brain sensitive to disruption of its supply. not only oxygen, but also glucose.

The damaging effect of hypoxia (anoxia) on the brain can be mainly at two levels:

Fetal hypoxia

Fetal hypoxia is a violation of its vital functions, which develops under the influence of oxygen deficiency during pregnancy and childbirth.

Most often, a lack of oxygen in the fetus manifests itself during pregnancy; it can be associated with a wide variety of problems, but most often it is caused by chronic diseases of the mother or gestosis. The prerequisites for fetal hypoxia are created by many disturbances in the normal course of the birth process.

Consequences of stress and hypoxia in adults

We spend most of the time of day at work every day. Time for rest and taking care of your health is becoming less and less. High mental stress and constant stress lead to chronic fatigue, decreased immunity, sleep disturbances and a general deterioration in health.

Intensive work in a confined space is only one of the many causes of chronic fatigue, increased fatigue, insomnia, decreased performance and is directly related to hypoxia.