Anaphylactic shock (anaphylaxis) is a state of greatly increased sensitivity of the body. It can occur as a result of repeated introduction into the body of foreign proteins, medicines, in case of errors in blood transfusion, even with the bite of some insects. Anaphylactic shock is one of the most dangerous complications of drug allergy. In about 10-20% of cases, anaphylactic shock is fatal.
Anaphylactic shock is accompanied by difficulty breathing, a decrease in blood pressure, etc. There are several degrees of anaphylactic shock: mild, moderate, severe and extremely severe. Also, anaphylactic shock can lead to predominant damage to some organs or organ systems.
Anaphylactic shock often develops with lightning speed, so it is almost impossible to predict it. However, you can trace allergic reactions to a particular substance and further avoid its ingestion. Anaphylactic shock is sometimes preceded by some specific symptoms, that is, we can talk about the possible presence of a prodromal period.
Even an insect bite can cause anaphylactic shock. Of course, not every person. To understand what it is - anaphylactic shock, you can give a simple example. Probably every person has been bitten by a bee or a wasp at least once in his life - an unpleasant, but not dangerous feeling. Not dangerous for most, but not absolutely for everyone. Some people, after a seemingly harmless bite, begin to choke and may even lose consciousness. The thing is that the human body reacts very inadequately to such a bite - this is anaphylactic shock.
One of the most sensitive signs of anaphylaxis is decreased blood flow. The blood flow begins to decrease sharply (therefore, anaphylactic shock can develop with lightning speed). First, the peripheral circulation is disturbed, and then the central one. This occurs under the influence of histamine and other mediators, which are produced in large quantities by the cells of the body. Due to a decrease in blood flow, the skin becomes pale. The skin is cold and damp to the touch. Also, due to circulatory disorders, there is anxiety in the brain and other organs. This situation is characterized by clouding of consciousness (up to its loss, since the brain and other organs do not receive enough oxygen due to circulatory disorders), problems with breathing (shortness of breath). Urination is often disturbed.
A harbinger of anaphylaxis is a local reaction where the allergen enters the human body. And this is not even so much a harbinger of anaphylactic shock as its first symptom. The local reaction is pronounced. It can be very severe pain, swelling in the place that was bitten by an insect or where an injection of the drug was made. Severe itching of the skin is often noted. If the allergen gets inside the body, then anaphylactic shock begins with a sharp pain in the abdomen. In this case, the patient has nausea, vomiting. That is, in this case, we can talk about the symptoms of dysfunction of the gastrointestinal tract (gastrointestinal tract). The oral cavity and larynx are swollen.
Shortness of breath is characteristic of anaphylactic shock. Difficulty breathing is caused by laryngeal edema, bronchospasm. "Asthmatic" breathing, that is, hoarse, rapid, noisy, always accompanies the development of anaphylactic shock. In addition to difficulty breathing, anaphylaxis is characterized by pale skin and bluish lips, fingers, visible mucous membranes, and a drop in blood pressure.
In some patients in a state of anaphylactic shock, convulsions are observed, foam may appear from the mouth, urination and defecation may occur involuntarily, and bloody discharge from the vagina is also possible. All this creates a life-threatening situation for the patient.
Death can occur within minutes or hours after the onset of anaphylactic shock, that is, after the allergen enters the body. If the patient loses consciousness, he may die from suffocation in the first 5-30 minutes after the allergen enters his body. If there are severe and irreversible changes in organs that are vital, then death can occur one or two days after the onset of anaphylactic shock.
If, as a result of anaphylaxis, changes occur in the heart, in the brain (for example, cerebral edema or hemorrhage in the brain), in the gastrointestinal tract (for example, intestinal bleeding), in the kidneys, then a person may die after a much longer period of time compared to the cases described above.
In addition, the state of anaphylactic shock is characterized by a situation in which, some time after the improvement of the general condition of the patient, a sharp decrease in blood pressure can again be observed. As a result of all of the above, those persons who have experienced anaphylaxis should be monitored in a hospital for at least two weeks.
There are several degrees of severity of anaphylactic shock. There are four of them.
The first degree is easy. Anaphylactic shock lasts from several minutes to two hours. In this case, it is characterized by the presence of itching of the skin, hyperemia of the skin (that is, increased blood circulation in a tissue or organ - in this case, tissue). The patient has a headache, dizziness, a feeling of heat, tachycardia, discomfort in the body, a feeling of tightness in the chest, shortness of breath and increasing weakness.
The second degree is moderate. For anaphylactic shock, in this case, a more detailed clinical picture is characteristic, compared with a mild degree. It is represented by Quincke's edema (this is an acute allergic reaction associated with rashes in the human body, accompanied by tissue edema), increased heart rate, arrhythmias, pain in the heart, and a decrease in blood pressure. The patient often has conjunctivitis and stomatitis. The patient may experience feelings of excitement, anxiety, and fear. He may have decreased hearing and a noise in his head. All this is accompanied by severe weakness. Many patients have renal syndrome, such as urinary frequency and gastrointestinal syndrome. The latter can include bloating and severe abdominal pain, nausea and vomiting, etc.
The third degree is severe. Anaphylaxis in this case is associated with the development of acute cardiovascular and respiratory failure. This can be a sharp drop in blood pressure, shortness of breath, stridor breathing. The latter is a high-pitched sound that appears as a result of breathing out or inhaling air through a narrowed breathing tube - such a narrowing can occur as a result of inflammation of the bronchial mucosa. Very often, severe anaphylactic shock is accompanied by loss of consciousness.
The fourth degree is extremely difficult. Anaphylactic shock leads to the instantaneous development of collapse. Collapse is a condition of the body that is associated with a sharp decrease in blood pressure, a sharp drop in vascular tone, deterioration of blood circulation, as a result of which vital organs suffer (for example, the flow of venous blood to the heart is significantly reduced, arterial and venous pressure decreases, and brain hypoxia). The state of collapse threatens the patient's life. Also, anaphylaxis in this case can lead to a coma, which is associated with the rapid loss of consciousness of the patient. In this case, urination and defecation occur involuntarily.
For the fourth degree of anaphylactic shock, the following symptoms are also characteristic: dilated pupils, lack of their response to light. If blood pressure continues to fall, then the pulse becomes undetectable. Cardiac arrest and cessation of breathing are possible.
Anaphylactic shock can damage individual organs or systems. In this case, the defeat does not extend to the entire organism, but mainly to some of its parts. Such options for anaphylactic shock include the following.
Anaphylactic shock with a predominant lesion of the skin is characterized by the presence of Quincke's edema, urticaria and severe pruritus, which tends to grow.
Anaphylactic shock with a predominant lesion of the nervous system is determined by the presence of a severe headache in the patient. A characteristic feature is also the presence of nausea and the appearance of seizures, accompanied by involuntary defecation and urination. The patient often loses consciousness.
Anaphylactic shock with a predominant lesion of the respiratory system is associated with the patient's suffocation. In this case, they talk about the asthmatic variant of anaphylaxis. The patient develops asphyxia (that is, a critical state of the body, which is characterized by the accumulation of carbon dioxide due to a lack of oxygen in the body). The reason is the obstruction of the upper respiratory tract. This is due to laryngeal edema, as well as a violation of the normal patency of the middle and small bronchi.
Anaphylactic shock with predominant heart damage is characterized by the development of myocardial infarction or acute myocarditis. In this case, they speak of cardiogenic anaphylaxis.
Anaphylactic shock is characterized by the presence of a period of resistance. This period lasts for the first two or three weeks after anaphylaxis. The period is characterized by the gradual disappearance of allergy manifestations. A patient who has undergone anaphylactic shock must be extremely careful. In order to prevent the re-entry of the allergen into the body, due to which anaphylactic shock developed. The reason for this is that with repeated ingestion of such an allergen, the course of anaphylaxis is more severe. This also applies to those cases when a sufficiently long period of time (months and years) has passed after anaphylactic shock.
Anaphylactic shock can cause many complications. These include the development of myocarditis (that is, allergic damage to the heart muscle), hepatitis (allergic liver damage), glomerulonephritis (allergic kidney damage), as well as various lesions of the nervous system, etc. Possible complications of anaphylactic shock include exacerbation of existing chronic diseases.
In anaphylactic shock, confusion should not be allowed. This means that medical care for a patient in a state of anaphylaxis should be provided extremely quickly and clearly. The correct sequence of actions must be followed. Firstly, it is immediately required to stop the effect of the allergen on the patient's body. If the state of anaphylactic shock has developed as a result of the introduction of a drug into the body, then it is necessary to suspend its introduction. If the cause of anaphylactic shock is an insect bite (for example, a bee), then it is necessary to immediately (but, nevertheless, very carefully) remove the sting from the place with the poisonous sac.
If there is an objectively determined possibility, then it is recommended to apply a tourniquet above the site of the bite or injection of the drug, and then, in order to prevent the spread of the allergen throughout the body, this place should be injected with an adrenaline solution. This will help create a local spasm of the blood vessels.
After the above actions, the patient should be helped to accept a position in which the likelihood of tongue sinking will be minimal. In this case, the penetration of vomit into the respiratory tract will also be prevented. A patient in a state of anaphylactic shock must provide fresh air to the body. An oxygen bag can be used. All this refers to the first measures, on which the success of further treatment largely depends.
Further treatment of anaphylaxis is carried out with the aim of neutralizing biologically active substances, normalizing the general condition of the patient. As a result of appropriate treatment, the respiratory and cardiovascular activity of the body is normalized. It is important to prevent the development of complications after anaphylactic shock.
Anaphylactic shock is predictable. In most cases, this is far from the case. The state of anaphylaxis is impossible to predict. However, it is quite possible for each person to pay close attention to how the body reacts to certain foods, to this or that substance, to insect bites, etc. If allergic reactions are noted, then it is necessary to strictly beware of their repeated entry into the body. After all, it is a repeated hit that can lead to a state of anaphylactic shock. Thus, it can be concluded that the prevention of anaphylactic shock largely depends on a carefully collected allergic history.
Observations and studies have shown that anaphylactic shock develops only (!) As a result of repeated exposure to the allergen on the body. If the patient has not previously been exposed to an allergen, then he is out of danger of developing anaphylactic shock.
Also, science knows that the state of anaphylaxis is usually preceded by allergic reactions that do not lead to it. Those persons who have suffered a state of anaphylactic shock should always have a card on which the allergen leading to anaphylaxis is indicated. You must have a special anaphylactic kit, which will be used if necessary. All this, of course, should always be with you (and not just at home in a secluded place).
The type of allergen does not affect the general clinical picture of the patient's condition. The allergen does not affect the severity of the state of anaphylaxis. As a result of the above, it can be concluded that the clinical picture of anaphylaxis is diverse, this can be judged on the basis of the following data: when comparing five hundred cases of anaphylactic shock, each of which was caused by different allergens, not even two cases were recorded, such that the clinical picture coincided. Each case of development of anaphylaxis had its own set of symptoms, differed from others in the severity of the course, could have prodromal (that is, previous) phenomena, or might not.
Anaphylactic shock is characterized by the presence of a prodromal period. To be more precise, it should be said that the state of anaphylaxis may be preceded by a prodromal period, but it may not be. In the latter case, anaphylactic shock develops instantly and leads to collapse - the patient loses consciousness. This condition is characterized by the presence of seizures. Often a person dies.
The opinion of some authors investigating the problem of anaphylactic shock is that some of the elderly who die, seemingly from cardiovascular failure, actually die from anaphylactic shock as a result of, for example, an insect bite.In this case, timely medical assistance often cannot be provided.
If the prodromal period does occur, then its duration varies from only a few seconds to an hour. The prodromal period is usually associated with the appearance in the patient of a feeling of heat, excitement or weakness and depression, chest pain, which can be characterized as constriction, headache and some other phenomena. Quite often (but still not always) in the prodromal period the following phenomena occur: itching of the skin, lacrimation, perspiration and cough (dry). A rash may appear on the skin, swelling is likely. The prodromal period ends with the appearance of symptoms that outline the actual picture of anaphylactic shock.