Oxygen is necessary for the normal functioning of the body. Too long a state of oxygen deficiency (hypoxia) is very dangerous for the brain and other organs - for example, the heart. They can lead to permanent disability or even death.
Cerebral hypoxia can have many different causes and is due to dysfunction of various systems in the body. The consequences of this condition are a direct threat to life. Cerebral oxygen deficiency requires rapid transport of the patient to the hospital and appropriate therapy. Only through it can serious consequences be prevented.
Cerebral hypoxia
The brain is an organ that needs a huge amount of oxygen. Although it is relatively small, it consumes 20% of the gas that enters the body. It also responds very poorly to reduced oxygen supply. The minimum threshold is about 3.3 ml of oxygenated blood per 100 g of brain tissue. If this indicator decreases, irreversible damage may occur within a few minutes.change or even death. Brain tissue is extremely sensitive to hypoxia - even 3-4 minutes of oxygen deficiency can permanently impair the work of some of its areas. The consequences of oxygen deprivation of the brain are serious. Long, tedious rehabilitation is often necessary to return to full he alth.
Symptoms of cerebral hypoxia
The body responds quickly to reduced oxygen supply. Symptoms of oxygen deficiency are primarily headache, nausea, vomiting, problems with short-term memory, cognitive disorders. Then there is fainting and loss of consciousness. If the patient does not receive proper care, death can occur. There is more than one cause of cerebral hypoxia, and specific symptoms can help identify it. Their violent appearance indicates a failure of the circulatory system, which does not provide sufficient oxygenated blood to the brain.
Oxygen deficiency of the brain can also appear in fans of extreme sports. Altitude sickness affects people who have not adapted the body to a longer stay at an altitude above 2500 m above sea level. The rarefied air contains little oxygen, which can lead to respiratory and oxygen heart failure. Diving enthusiasts should also be especially careful. Rapidly changing pressure has a direct effect on the human body - under the influence of a too rapid rise, the nitrogen accumulated in the blood takes the form of bubbles and causesblockages that lead to cerebral ischemia. Hypoxia can also have a chronic course - it is accompanied by prolonged fatigue, problems with memory, concentration and drowsiness.
Oxygen deficiency of the brain: causes
Brain hypoxia can be caused by malfunctions of many systems and organs in the body. These include:
- cardiac arrest - for example as a result of a heart attack;
- impaired normal circulatory function, arterial occlusion associated with atherosclerosis, embolism, thrombosis;
- sudden drop in blood pressure due to anaphylactic, hemorrhagic shock;
- developed anemia;
- respiratory disorder associated with pneumonia, asthma, emphysema, pneumothorax, sleep apnea.
Often the cause of hypoxia is cardiac arrest. Diabetes is also a serious risk factor - in the advanced course of this disease, changes in blood vessels occur, which leads to serious disturbances in the functioning of the whole organism. This may also be the case in older people suffering from atherosclerosis and other diseases associated with the circulatory and respiratory systems.
Types of brain hypoxia
Depending on the degree of ischemia, there are several types of ischemia.
- Complete cerebral ischemia (cerebral infarction) leads to cerebral hypoxia and is associated with a cessation of blood supply to the entire organ or area. Already after 2minutes, the oxygen supply in the cells is depleted, and the processes leading to their death develop rapidly.
- Partial cerebral hypoxia - associated with reduced blood flow.
- Anoxia - insufficient oxygenation of the blood.
- Anemia - caused by a deficiency of hemoglobin.
- Hypoxemic type - a decrease in the partial pressure of oxygen in arterial blood.
- Histotoxic type - associated with an enzymatic defect.
Oxygen deficiency in a newborn
Fetal hypoxia is a lack of oxygen in the blood or tissues. Mechanisms responsible for child hypoxia include:
- abnormal flow of oxygen through the placenta;
- improper gas exchange through the placenta;
- other diseases in a woman.
Sometimes, during or immediately after birth, the baby's brain is hypoxic. Then there is the so-called perinatal hypoxia. This can happen, for example, as a result of cord pressure, improper oxygenation of the fetus.
Diagnosis of intrauterine oxygen deficiency
Diagnosis of fetal well-being is based on:
- cardiotocography;
- capillary blood test;
- gasometric test.
The first signal of hypoxia is an abnormal cardiotocography of a child (CTG). A persistently rapid heart rate (tachycardia) indicates a slight lack of oxygen, and then onset of bradycardia during uterine muscle contractions indicates a long-term oxygen deficiency. This means that the child is in an emergency.position and preferably resolve the pregnancy as soon as possible.
Capillary blood test is the taking of micro-samples of blood from a child (most often the head) to determine the pH value. The pH value of the blood indicates that acidosis is due to hypoxia. Nowadays, this test is often performed in conjunction with a gasometric test.
The gasometric test allows you to control violations of the acid-base balance and gas exchange of the body. In a newborn baby, a blood sample can be taken from an artery or umbilical cord for examination. The partial pressure of carbon dioxide (pCO 2) and the partial pressure of oxygen (pO 2) are determined, as well as the level of oxygen saturation of the blood.
The greater the intrauterine oxygen deficiency, the more extensive the area of hypoxia. When oxygen is deficient, a baby can consume meconium in utero. Local oxygen deficiency leads to increased intestinal peristalsis and intrauterine consumption of meconium. This is proof that the child was in an emergency.
Influence of perinatal hypoxia
Perinatal hypoxia can cause abnormal adaptation of the newborn to independent living. Aspiration of the respiratory mucosa and respiratory distress syndrome may occur. There may also be brain damage (ischemia, encephalopathy). Some children have minor developmental dysfunctions that can be easily corrected, others may experience neurological abnormalities such as cerebral palsy orepilepsy.
Currently, many of the consequences of perinatal hypoxia are preventable. Careful evaluation of the fetus during labor, early intervention, and rapid completion of labor can eliminate or reduce the risk of brain damage to the baby. Advances in neonatology and new treatments (such as head hypothermia) are showing good results.
Cerebral hypoxia: first aid
The goal of first aid is to begin transporting oxygen to the brain as soon as possible. For this, artificial respiration and heart massage are usually done. They are performed according to the compression of the heart in the middle of the chest and breathing using the mouth-to-mouth method. If the airway is blocked by a foreign body, you can try to remove it. It is much worse if the blockage of the airways is the result of swelling of the larynx (for example, in diseases of the respiratory system or an allergic reaction). Airway obstruction then requires the administration of special medications and, in extreme cases, a tracheotomy.
It is necessary to call an ambulance for the sick person. Prior to her arrival, if possible, information about the victim should be collected, including what medications they are taking, if they are allergic to anything, if they have a chronic illness or have recently been ill (for example, a heart attack), or have had surgeries..
Cerebral hypoxia: treatment
Treatment of cerebral hypoxia always occurs inhospital, and its purpose is also to initiate the transfer of oxygen to the brain. The detailed course of therapy depends on the cause of cerebral oxygen deficiency.
Fortunately, the brain is a neuroplastic organ, so appropriate rehabilitation exercises and regular use of hyperbaric oxygen therapy allow the creation of new neural circuits that perform the functions of damaged neural groups. In case of cerebral oxygen deficiency, treatment should be carried out with the participation of specialists in hospital or rehabilitation centers and on an individual basis, taking into account the causes of hypoxia and its duration.
