Complications of anaphylactic shock. Signs of anaphylactic shock and how to help

Version: Directory of Diseases MedElement

Anaphylactic shock unspecified (T78.2)

Traumatology and Orthopedics

general information

Short description

I. Inclusions and exclusions

Anaphylaxis.

2.1 Anaphylactic shock coded elsewhere:
- "Anaphylactic shock caused by pathological reaction to food" - T78.0

- "Anaphylactic shock associated with the administration of serum" - T80.5

- "Anaphylactic shock due to a pathological reaction to an adequately prescribed and correctly applied drug" - T88.6

2.2 Other types of shock, unspecified:
- "Shock caused by anesthesia" - T88.2

- "Shock during or after procedure, not elsewhere classified" T81.1

- "Shock, unspecified" - R57.9

- "Other types of shock" - R57.8

- "Maternal shock during or after labor and delivery" - O75.1

- "Shock due to abortion, ectopic and molar pregnancy" - O08.3

2.3 Unspecified types of allergies and symptoms similar to it, occurring without hemodynamic disturbance:
- "Allergy, unspecified" - T78.4

- "Asphyxia" - R09.0

Note 1. In general, T78 "Adverse effects not elsewhere classified" should be used when coding for a single cause as the primary code to identify adverse effects not elsewhere classified due to an unknown, uncertain or ill-defined cause. When multiple-coded, this rubric can be used as an additional code to identify the impact of conditions classified in other rubrics.
Excludes: complications due to surgery and medical procedures, not elsewhere classified (T80-T88).

II. Terminology

There are significant differences in terminology in various medical communities that make it difficult to evaluate research results. The following definitions reflect the most commonly used or known approaches.

Anaphylaxis- allergic reaction immediate type(antigen-antibody reaction), a state of sharply increased sensitivity of the body that develops with the repeated introduction of an allergen.

Anaphylactic shock(AS) - the most severe form of anaphylaxis, characterized by acute hemodynamic disturbance Hemodynamics - 1. A section of the physiology of blood circulation that studies the causes, conditions and mechanisms of blood movement in the cardiovascular system based on the use of the physical laws of hydrodynamics. 2. The totality of the processes of blood movement in the cardiovascular system
leading to circulatory failure and hypoxia of all vital organs.

Anaphylactoid reactions are clinically similar to anaphylactic, but are not caused by the interaction of the antigen with the antibody, but by different substances, for example, anaphylactoxins C3a, C5a. These substances directly activate basophils and mast cells and cause their degranulation or act on target organs.

Evolution of terminology reflecting the clinical approach to the problem:

1. Anaphylaxis is a severe life-threatening, generalized or systemic hypersensitivity reaction.

According to a task force committee of the American Academy of Allergy, Asthma, and Immunology (AAAAI), the American College of Allergy, Asthma, and Immunology (ACAAI), and the Joint Council of Allergy, Asthma, and Immunology (JCAAI), the definition of a reaction is extended with the words "often life-threatening and almost always unforeseen." Minor, local or non-systemic reactions are outside the definition of anaphylaxis.

Anaphylaxis can be divided into "allergic anaphylaxis" and "non-allergic anaphylaxis". The clinical manifestations of allergic and non-allergic anaphylaxis may be identical.

The Committee of the European Academy of Allergology and Clinical Immunology (EAACI) has suggested using the term "allergic anaphylaxis" only when the reaction is mediated by immunological mechanisms (such as IgE, IgG, or complement activation by immune complexes).
Anaphylactic reactions mediated by IgE antibodies are referred to as "IgE mediated allergic anaphylaxis".
The term "anaphylactoid" reactions was introduced for non-IgE-mediated reactions, but the EAACI committee recommended that this definition not be used further.

2. Anaphylactic shock is defined as an acute, potentially fatal, multi-organ systemic reaction due to the release of chemical mediators from mast cells and basophils.

Thus, most consensuses tend to think that "anaphylaxis" and "anaphylactic shock" are synonymous and, if the latter is mentioned, the so-called "shock without shock", that is, anaphylaxis without pronounced hemodynamic changes, can be implied.

Note 2.
The treatment of anaphylactic and anaphylactoid reactions does not differ, therefore, further in this subheading, they are not separated.
Additional codes may be used for encoding, provided they are not associated with known triggers (see exceptions to this sub-heading above). For example, codes W57 "Bite or sting by non-venomous insects and other non-venomous arthropods", W56 "Contact with a marine animal", and X20-X29 "Contact with poisonous animals and plants" may be used.

Flow period

Anaphylactic shock is an acute reaction. Depending on the route of entry of the antigen and other factors, it can develop in a period from several minutes (seconds) to 2 hours.
In extremely rare cases, a biphasic (two-stage) course is noted, when a relapse of anaphylaxis symptoms occurs after 1-72 hours with adequate therapy, and the second episode can be much more severe than the first and even have a fatal outcome.

Classification

There is no single classification that covers all manifestations of anaphylactic reactions in terms of form and severity, together with the mechanisms of their implementation and triggers. The following list of types of anaphylaxis cannot be considered a complete or generally accepted classification, cannot be fully assigned to this subheading, and is provided for educational purposes only. Many of the terms have lost (or do not have) clinical meaning, are not recognized by all medical communities, but can be found in various texts.

I. Types of anaphylaxis:
1. Active anaphylaxis (a. activa) - anaphylaxis resulting from the formation of antibodies in the body.
2. Passive anaphylaxis (a. passiva) - anaphylaxis caused after the introduction into the body of allergic antibodies from an actively sensitized donor.
3. Passive direct anaphylaxis (a. passiva directa) - passive anaphylaxis caused by the introduction of an allergen after the preliminary introduction of allergic antibodies.
4. Passive reverse anaphylaxis (a. passiva reversa) - passive anaphylaxis caused by the introduction of allergic antibodies after the preliminary introduction of the allergen.

II. Classification of anaphylactic and anaphylactoid reactions

1. Anaphylactic reactions:
- mediated IgE;
- mediated IgG;
- IgE mediated and physical activity.

2. Anaphylactoid reactions:
- mediated by direct release of mediators;
- under the influence of drugs;
- under the influence of food;

Under the influence of physical factors (physical activity, cold, etc.);
- with mastocytosis;
- mediated by immunoglobulin aggregates or immune complexes;
- mediated by IgG aggregates (when using normal immunoglobulin);

Mediated by immune complexes, the formation of anti-IgA and IgG to IgA (when using normal immunoglobulin for intravenous administration);

With the on / in the introduction of immune sera (anti-thymocyte immunoglobulin, anti-lymphocyte immunoglobulin);
- mediated by cytotoxic antibodies (during blood transfusion);
- to erythrocytes;
- to leukocytes;
mediated by radiopaque agents.

3. Reactions caused by the use of aspirin and other NSAIDs.

4. Idiopathic reactions.

III. The clinic describes the following types (forms) of anaphylaxis:

1. Immunologically IgE-mediated reactions.

2. Immunological reactions for aspirin, NSAIDs and ACE inhibitors. They are separated into a separate group because they combine the manifestations of IgE-mediated and IgE-independent reactions. In the past, they were defined as IgE-independent, but recent studies show that it is in anaphylactic shock that mainly IgE-mediated mechanisms are realized.

3. Immunologically IgE-independent reactions (including IgG-mediated).

4. Non-immunological reactions.

5. Idiopathic anaphylaxis. It is a syndrome of recurrent anaphylaxis in which triggers cannot be identified despite an exhaustive search. This recurrent syndrome should be distinguished from a single episode of anaphylaxis, for which the etiology may not be clearly defined (up to 25% of all cases of anaphylaxis).
Idiopathic anaphylaxis can be defined as a cumulative sequence of infrequent (< 6 раз в год) эпизодов анафилаксии или частых эпизодов анафилаксии (≥ 6 эпизодов в год или два или более эпизодов в течение последних 2-х месяцев).

6. Menstrual anaphylaxis is a variant of idiopathic anaphylaxis in a female population. In this case, anaphylaxis is associated with menstrual cycle. With a clinic of anaphylactic shock, it is extremely rare. Most of these patients respond to changes in blood levels of progesterone and the diagnosis can be confirmed with low doses of progesterone, which causes anaphylaxis.

7. Biphasic and persistent anaphylaxis. About biphasic anaphylaxis should be discussed with a recurrence of symptoms within 1-72 hours (usually after 8-10 hours), subject to adequate therapy. Sustained anaphylaxis should be considered when the symptoms remain unchanged or with minor changes for 5-32 hours against the background of standard therapy.
The incidence of biphasic anaphylaxis is estimated to be 23% in adults and 11-17% in children.

8. Anaphylaxis caused by exercise. In some cases, the trigger may be food intake and subsequent exercise, and each of the factors taken separately may not cause anaphylaxis.

9. Anaphylaxis induced by contact with natural latex. Three groups with a high risk of reaction to latex were identified: medical workers, children with spina bifida and genitourinary anomaly, and workers who are professionally in contact with latex. In groups with anaphylaxis to natural latex, there is a high percentage of cross-allergy to kiwi and some other tropical fruits.

10. Anaphylaxis caused by seminal fluid is extremely rare. Usually contact causes predominantly local reactions.

IV. Clinical Options course of anaphylactic shock.
Despite the fact that the very definition of anaphylaxis is based on the principle of a generalized (polysystemic) reaction, some authors, depending on the predominance of a particular symptom, distinguish five variants of anaphylactic shock: asphyxial, hemodynamic (collaptoid), cerebral, thromboembolic, abdominal.

V. Severity of anaphylactic shock.
According to the severity of hemodynamic disturbances, some authors traditionally, as in all types of shocks, distinguish 4 degrees of severity (some authors have 3 degrees of severity).

Etiology and pathogenesis

Etiology
For a list of root causes, see the "Classification" section.
Anaphylactic shock (AS) is coded as unspecified if the etiological factors cannot be determined or are not specified in other ICD-10 subcategories.

Pathophysiology

Mediators released upon activation of mast cells and basophils cause a variety of changes in the cardiovascular system, respiratory organs, gastrointestinal tract and skin.

Process steps

I stage. Immunopathological stage, during which the body is sensitized with the formation IgE antibodies to the antigen. At the same time, IgE binds reversibly to the receptors of mast cells and basophils (anaphylaxis effector cells).

II stage. The pathochemical stage that occurs in cases of re-entry into the body of the allergen that caused sensitization, and is characterized by the formation of the allergen-IgE complex, activation of effector cells, the release of biologically contained and the synthesis of new ones. active substances. At the same time, the allergen-IgE complex activates humoral enhancement systems (complement system, blood coagulation system, etc.).

III stage. Pathophysiological stage, during which biologically active substances have a damaging effect on the organs and tissues of the patient. Thus, the development of true anaphylaxis is associated with the mandatory presence of an immunological phase.

Biologically active substances and their action

1. Histamine causes:
- contraction of the smooth muscles of the bronchi;
- swelling of the mucous membrane of the respiratory tract;
- increased production of mucus in the airways, contributing to their obstruction;
- contraction of smooth muscles of the gastrointestinal tract (tenesmus, vomiting, diarrhea);
- decrease in vascular tone and increase in their permeability;
- erythema, urticaria, angioedema, due to increased vascular permeability;

Decreased BCC due to decreased venous return.

2. Leukotrienes cause spasm of the smooth muscles of the bronchi and increase the effect of histamine on target organs.

3. Kallikrein secreted by basophils is involved in the formation of kinins, which increase vascular permeability and lower blood pressure.

4. Platelet activating factor stimulates the release of histamine and serotonin by platelets. They, in turn, cause spasm of smooth muscles and increase vascular permeability.

5. Anaphylactic factor of eosinophil chemotaxis stimulates the influx of eosinophils and their production of biologically active substances that block the action of mast cell mediators.

6. Prostaglandins increase smooth muscle tone and vascular permeability.

In anaphylactoid reactions, there is no immunological stage, and the pathochemical and pathophysiological stages proceed without the participation of allergic IgE with excessive release of mediators in a nonspecific way. Three groups of mechanisms are involved in the pathogenesis: histamine, disturbances in the activation of the complement system, and disturbances in the metabolism of arachidonic acid. In each case, the leading role is assigned to one of the mechanisms.
Whatever type of reaction is diagnosed, its essence comes down to the release of the same mediators as in the IgE-mediated reaction.

Pathoanatomy

AS is heterogeneous in terms of morphological changes. Most characteristic:
- damage to blood vessels in the form of a violation of permeability;
- perivascular necrosis;
- thrombosis of vessels of various organs;
- bronchospasm;
- acute emphysema of the lungs and more.

In the study of tissues and organs, blood deposition in some areas and anemization in others, dystrophic changes caused by prolonged tissue hypoxia, and more are revealed.
A more detailed description of morphological lesions is only of relative importance, since clinical and functional disorders in such patients are not limited to the narrow boundaries of certain territories.
Careful morphological analysis is a necessary component of a comprehensive study of each lethal case of AS. However, the modern pathoanatomical characterization of this condition should be clinical and anatomical. Morphological confirmation of the reactive nature of AS is sometimes eosinophilia, widespread or more localized in certain organs and tissues.

Epidemiology

Age: mostly young

Sign of prevalence: Rare

Sex ratio (m/f): 0.65

The true frequency of anaphylaxis is unknown. Some physicians use the term for full blown severe reaction syndrome when describing it, while others use it to describe milder cases as well.

Frequency anaphylactic shock, as the most severe form of anaphylaxis, is 1-3 cases per 100,000 patients.
The incidence of anaphylaxis is increasing, which is associated with an increase in the number of potential allergens to which people are exposed.

Age Patients are predominantly children and young. In childhood, the highest prevalence of anaphylaxis occurs at 12-18 months, in adults - at 17-39 years.

Floor. slight predominance of women.

Factors and risk groups

Factors that increase the risk of anaphylaxis:
- history of allergic reactions;
- atopic dermatitis, bronchial asthma, allergic rhinitis;
- mastocytosis;
- burdened by anaphylaxis family history;
- prolonged contact with a large number of potential allergens;
- smoking.

Factors that increase anaphylaxis when it occurs and worsen the prognosis:
- beta-blockers and ACE inhibitors ACE - angiotensin converting enzyme
;
- alcohol;
- sedatives, sleeping pills, antidepressants;
- cardiovascular diseases;
- acute infections.

Clinical picture

Clinical Criteria for Diagnosis

Rapid onset and development of symptoms; dyspnea; expiratory dyspnea; skin rash; skin itching; swelling of the lips; swelling of the tongue; swelling of the face; acute arterial hypotension; tachycardia; abdominal pain; bloating; cough; hoarseness of voice; disturbance of consciousness; dizziness; chest pain; hives; vomit; metallic taste in the mouth; anxiety; fear; bradycardia; panic

Symptoms, course

I. Anaphylaxis

Anaphylaxis can present with clusters of symptoms, many of which can be initially attributed to other diseases. Some symptoms may prevail in the clinic or develop faster than others.

According to criteria of the World Allergy Organization(2011, updated 2012, 2013), anaphylaxis is most likely if the condition meets at least one of the criteria below:

1. There is an acute onset and development (from a minute to 2 hours) with involvement of the skin and mucous membranes, including several organs (for example, swelling of the lips, tongue, larynx in combination with a generalized urticarial rash, accompanied by redness and itching), and at least one of the following:
1.2 Respiratory symptoms (dyspnea, bronchospasm, stridor, decreased expiratory flow - expiratory dyspnea, hypoxemia - cyanosis or decreased SpO 2, respiratory arrest).
1.2 Arterial hypotension or symptoms of dysfunction of other organs caused by it (collapse, syncope, syncope, impaired consciousness, pallor of the skin, bradycardia followed by cardiac arrest, ECG changes in the type of ischemia in a number of patients).

2. Two or more of the following signs, subject to patient exposure to suspected allergens (or exposure to other suspected triggers). The condition of an acute onset and flow must also be met (see paragraph 1):
2.1 Involvement of the skin and mucous membranes (for example, swelling of the lips, tongue, larynx, in combination with a generalized urticarial rash, accompanied by redness and itching.
2.2 Respiratory symptoms (dyspnea Dyspnea (synonymous with shortness of breath) is a violation of the frequency, rhythm, depth of breathing or an increase in the work of the respiratory muscles, which is manifested, as a rule, by subjective sensations of lack of air or difficulty breathing
, bronchospasm Bronchospasm - narrowing of the lumen of the small bronchi and bronchioles due to spastic contraction of the muscles of the bronchial wall
, stridor Stridor is a whistling noise that occurs mainly during inspiration, due to a sharp narrowing of the lumen of the larynx, trachea, or bronchi.
, decrease in expiratory flow - expiratory dyspnea, hypoxemia - cyanosis or decrease in SpO 2).
2.3 Arterial hypotension (collapse, syncope Syncope (syncope, fainting) is a symptom that manifests itself as a sudden, short-term loss of consciousness and is accompanied by a fall. muscle tone
, syncope, impaired consciousness, tachycardia, bradycardia Bradycardia is a low heart rate.
, cardiac arrest).
2.4 Persistent gastrointestinal symptoms (vomiting, cramps and/or abdominal pain).

3. Arterial hypotension that occurred after contact with an allergen known to the patient, subject to the acute onset and course of the process:
3.1 Infants and children: low systolic blood pressure (based on age norms) or decreased systolic blood pressure more than 30% of the original.
3.2 Adults: systolic blood pressure less than 90 mm Hg. or a drop in systolic blood pressure greater than 30% of normal (working) pressure.

II. Anaphylactic shock

Anaphylactic shock is primarily manifested by the classic picture of shock:
- arterial hypotension;
- violation of microcirculation (pallor of the skin and mucous membranes, cold extremities);
- compensatory in relation to the decrease in cardiac output tachycardia or bradycardia Bradycardia is a low heart rate.
(rhythm disturbances in patients with heart disease);
- disturbances from the central nervous system(impaired consciousness, convulsions, headache, especially in patients with a history of central nervous system pathology).
Only 90% of patients have a combination of arterial hypotension with any other manifestations of anaphylaxis. Other symptoms (for example, respiratory) do not have time to develop or are masked by the shock clinic.

Notes

1. Low blood pressure in children is defined as:
- systolic blood pressure less than 70 mm Hg for children aged 1 month to 1 year;
- less than 70 mm Hg. Art. + 2 * age in years, for children aged 1-10;
- less than 90 mm Hg. for children aged 11-17 years.

2. Normal heart rate HR - heart rate
defined as:
- 80-140/min. for children 1-2 years old;
- 80-120/min. for children 3 years old;
- 70-115/min. for children over 3 years old.

3. Infants are more prone to the prevalence of respiratory symptoms over arterial hypotension in the development of anaphylaxis. Anaphylactic shock in infants is more tachycardic than hypotensive. Respiratory manifestations in children are more common than skin and mucous membranes (95% versus 82%). Symptoms of shock (arterial hypotension) are observed in 17-18%, abdominal manifestations - in 33% of cases. Symptoms of two or more groups are noted in 95% of cases.

4. In general, the symptoms of anaphylaxis for adults are distributed approximately as follows: 85% - from the skin and mucous membranes, 60% - respiratory symptoms, 33% - arterial hypotension, 29% - gastrointestinal. More than 90% of patients have two or more groups of symptoms.

5. Other signs in adults include a metallic taste in the mouth and fear of death.

Diagnostics

General provisions
The diagnosis of anaphylactic shock (AS) is clinical. None instrumental methods examinations cannot confirm the diagnosis of AS. However, some research methods, conducted in parallel with the provision of care, may be useful in terms of differential diagnosis and diagnosis of complications.
Minimal monitoring includes pulse oximetry, non-invasive blood pressure, and 3-lead ECG. Monitoring should be carried out by a specialist who is able to competently interpret and respond to any changes.

ECG
In order to save time, monitoring is initially carried out in 3 leads (including - according to the Sky).
12-lead ECG monitoring and recording is indicated for patients with identified ischemia-specific or arrhythmias abnormalities (including for the purpose of differential diagnosis with cardiac shock). Monitoring and recording a 12-lead ECG should not be associated with a delay in treatment.
When interpreting the ECG, one should take into account the fact that changes in the picture can be caused by hypoxemia and hypoperfusion as manifestations of AS itself, the administration of adrenaline, or the initial myocardial disease.

Pulse oximetry
Low SpO 2 values ​​are indicative of hypoxemia, which in the case of AS usually precedes cardiac arrest.
Arterial hypoxemia can be observed in other similar conditions (for example, bronchial asthma or stenosing laryngitis), so it should be evaluated in conjunction with other anamnestic, clinical and instrumental data.

Plain chest x-ray indicated for stabilization of the condition for differential diagnosis and in the presence of auscultatory signs of lung pathology. It is desirable to take pictures on the spot.

CT, MRI and other methods are indicated for suspected PE PE - thromboembolism pulmonary artery(blockage of the pulmonary artery or its branches by blood clots, which are formed more often in large veins lower extremities or pelvis)
.

Laboratory diagnostics

General information

Anaphylaxis is primarily a clinical diagnosis, laboratory investigations are not usually required, are possible only after the incident, and are rarely warranted. However, if the diagnosis is unclear (especially in recurrent cases) or if other diseases must be excluded, some laboratory tests are considered indicated.
When taking "post factum" analyzes, it should be understood that the level of the most specific laboratory parameters may be slightly increased or decreased due to their consumption during the reaction.
There are no sufficiently sensitive and specific indicators to predict an anaphylactic reaction. For example, not all individuals with an increase in IgE may develop anaphylaxis. Nevertheless, a detectable increase in the levels of certain enzymes, mediators, immunoglobulins, in combination with the clinic, may support the diagnosis.

1.Histamine. Plasma histamine levels rise within 10 minutes of the onset of anaphylaxis but fall again within 30 minutes.
Urinary histamine levels in the urine are generally not reliable, as this may be affected by diet and bacteriuria.
Determination of the level of histamine metabolites is a more sensitive test, but the technique is not publicly available (determination of daily urinary excretion of methyl histamine).

2.Tryptase(formerly beta-tryptase). Peak levels occur 60 to 90 minutes after the onset of an episode and may persist for up to 5 hours.
The estimated positive predictive value of tryptase is approximately 90-92%, and the estimated negative predictive value of a normal tryptase level is 50-55%. Presumably, serial tryptase testing may improve diagnostic sensitivity.
Determination of basal levels of total and beta-tryptase between episodes of anaphylaxis may be useful in ruling out systemic mastocytosis Mastocytosis - chronic illness characterized by the proliferation of mast cells (mast cells) in the skin, lymph nodes, bone marrow, spleen and some other organs; more common in children
. Higher background concentrations of tryptase (>11.4 µg/L) may indicate mastocytosis or changes in monoclonal mast cells (eg, mutation). Biopsy may be needed to further analyze causes bone marrow and cytogenetic analysis.
Patients with mastocytosis constitutively produce more alpha tryptase, while people with anaphylaxis and other causes have normal levels of alpha tryptase between episodes of anaphylaxis.
During anaphylaxis, a total tryptase (alpha + beta)/beta ratio equal to or greater than 20 is consistent with mastocytosis, while a ratio of 10 or less suggests anaphylaxis of another etiology.

Elevations in histamine or tryptase levels do not correlate with each other, and some patients may have an increase in just one of the two.

Taking blood samples (5-10ml) for mast cell tryptase testing:

Primary sampling - immediately after the start of cardiopulmonary resuscitation (do not delay emergency treatment due to blood sampling);

Repeatedly - 1-2 hours after the development of symptoms;

Third time - 24 hours later or after recovery (for example, in the allergological department of the clinic); is necessary to assess the baseline level of tryptase, since in some people this figure is initially elevated.

3.5-hydroxyindoleacetic acid. Serves for laboratory differential diagnosis of carcinoid syndrome and is measured in daily urine.

4. IgE. The definition of general (non-specific) IgE does not play a role, since it has low sensitivity and specificity, although it may support the diagnosis if appropriate clinical and anamnestic data are available.
Specific IgE is certainly useful in screening for suspected allergens. However, the list of these suspected allergens must be fairly well defined; blind studies fail in more than half of the cases. In addition, many reactions (especially those associated with drugs) are not IgE-mediated.

5.Skin tests can be used to determine the trigger for anaphylaxis (for example, food allergy, drug allergy or an insect bite). See the following subheadings for more details:
- " " - T78.0

- " Serum-associated anaphylactic shock T80.5

- " Anaphylactic shock due to a pathological reaction to an adequately prescribed and correctly applied drug" - T88.6.

6.IgG4. The role of IgG4 tests is discussed. The indicator is not specific and is discussed mainly in connection with chronic autoimmune pancreatitis and assessment of response to therapy with systemic corticosteroids. The value of so-called "allergic food IgG panels" is currently being debated.

7.Eosinophilia. The detection of eosinophils in various body fluids is highly correlated with the diagnosis of allergic reactions, asthma, eosinophilic bronchitis, and allergic lesions of the gastrointestinal tract. Nevertheless, it must be taken into account that the detection of a high level of eosinophils in the blood may indicate in favor of another disease.
Thus, eosinophilia is not a sensitive and specific marker for the diagnosis and prognosis of anaphylactic shock, but its detection may support (in combination with other markers and clinic) the diagnosis of anaphylaxis.

8.Tests for markers of IgE-independent reactions. No other diagnostic tests can help assess the risk of recurrent IgE-independent reactions.

9.Metanephrines (normetanephrines) in serum and urine. The test is used for differential diagnosis with pheochromocytoma.

10.Vanillylmandelic acid. The content in the daily urine is used for differential diagnosis with pheochromocytoma Pheochromocytoma (syn. chromaffin tumor, pheochromoblastoma, chromaffinoma, chromaffinocytoma) is a hormonally active tumor originating from mature cells of chromaffin tissue, more often from the adrenal medulla
.

11. The content of serotonin in the blood. The test is used to diagnose carcinoid syndrome Carcinoid syndrome - a combination of chronic enteritis, fibrous valvulitis of the heart valve, telangiectasia and skin pigmentation, periodically accompanied by vasomotor disorders and sometimes asthma-like attacks; due to excessive intake of serotonin produced by carcinoid in the blood
.

12. Test panel for the determination of vasointestinal polypeptides. Differential diagnosis with gastrointestinal tumor or medullary carcinoma thyroid gland that are capable of secreting vasoactive peptides.

Differential Diagnosis

Anaphylaxis may begin relatively mildly and progress rapidly to life-threatening respiratory or cardiovascular failure.
Delaying the diagnosis and initiation of therapy until the development of multiple organ manifestations of anaphylaxis is risky because the severity of the reaction is difficult or impossible to predict at the time of the first symptoms.

Differential diagnosis should be carried out:

1. All shock states of a different nature:
- septic shock;
- cardiogenic shock;
- traumatic shock.

2. With shock conditions (including anaphylactic), classified in other headings.

3. With local allergic reactions, mild allergic reactions, allergic processes affecting one of the systems:
- urticaria;
- angioedema;
- allergic lesions of the gastrointestinal tract;
- bronchial asthma.

4. Diseases with one or more similar symptoms;
- acute myocardial infarction;
- stroke;
- TELA;
- perforation of the gastrointestinal tract;
- acute intestinal obstruction;
- hysteria (hysterical lump in the throat);
- malignant carcinoid syndrome;
- pheochromocytoma;
- medullary carcinoma of the thyroid gland;
- poisoning (for example, monosodium glutamate, mackerel fish);
- foreign body respiratory tract (especially in children);
- capillary leak syndrome.

Complications

Complications of anaphylaxis and anaphylactic shock should be divided into complications of the disease itself and complications of treatment.

1. Complications of anaphylaxis itself and anaphylactic shock:
- bradycardia Bradycardia is a low heart rate.
followed by cardiac arrest;
- stop breathing;
- kidney failure;
- respiratory distress syndrome and pulmonary edema;
- cerebral ischemia;
- DIC Consumption coagulopathy (DIC) - impaired blood clotting due to massive release of thromboplastic substances from tissues
;
- general hypoxia and hypoxemia.

2. Complications of therapy(meet in approximately 14% of cases and are associated primarily with the introduction of adrenaline and / or vasopressors and infusion load):
- tachycardia of various types;
- ischemia Ischemia is a decrease in blood supply to a part of the body, organ or tissue due to a weakening or cessation of arterial blood flow.
myocardium with the development of a heart attack;
- arrhythmia.

In the treatment of anaphylactic shock, one should always be ready to conduct immediate cardiopulmonary resuscitation according to standard ALS/ACLS algorithms.

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Treatment

I. General provisions

1. The condition is classified as deadly. Help should be provided by any healthcare professional as quickly as possible. Patients who have an autoinjector should be able to use it. Lay rescuers and medical staff should be trained in anaphylaxis. The fastest possible algorithm for providing assistance significantly reduces mortality.

2. The scope of assistance may vary depending on:
- places of assistance (stage of assistance);
- qualifications and experience of staff (for example, lack of training in cricoconicotomy or endotracheal intubation reduces the amount of care);
- the number of patients (a single patient should always be guaranteed the maximum amount of assistance; if there are several employees who know the required methods of providing assistance, assistance can be provided to several patients at the same time);

Equipment and available drugs.

3. Adrenaline is the first and main drug for the treatment of anaphylaxis. Doses of epinephrine are significantly different from those in cardiopulmonary resuscitation.
Other vasopressors do not replace the administration of adrenaline and may only be considered as drugs of choice for:
- ineffectiveness of the first and second doses of adrenaline;
- the development of significant complications against the background of the use of adrenaline.
The introduction of only antihistamines and / or systemic corticosteroids does not replace the administration of adrenaline and can be used after its administration and in the further treatment of anaphylaxis after the patient is removed from a critical condition.

4. The general principles of ALS/ACLS apply to both patient assessment (ABCDE) and cardiopulmonary resuscitation required in the event of circulatory arrest due to anaphylactic shock (AS).

II. General principles and approaches to therapy

1.Non-pharmacological approaches include:

Maintenance of airway patency (airway protection, use of invasive and non-invasive mechanical ventilation);
- supply of 100% oxygen;
- ECG monitoring and/or pulse oximetry;
- providing intravenous access (with the largest diameter catheter or needle), in extreme cases - intraosseous access;
- lying position with raised legs (for pregnant women on the left side);
- infusion of crystalloid solutions in order to maintain BCC.

2.Pharmacological therapy:
- adrenergic agents (adrenaline, epinephrine);
- antihistamines (diphenhydramine);
- H2 receptor blockers (cimetidine, ranitidine, famotidine);
- bronchodilators (albuterol);
- systemic corticosteroids (prednisone, methylprednisolone);
- glucagon;
- vaspressors (dopamine).

3. Surgical methods. Cricothyreotomy (cricoconicotomy) followed by high-frequency artificial ventilation if orotracheal intubation is difficult or impossible.

III. Algorithm urgent action slightly different in the manuals of different countries. The following is a management model based on the "World Allergy Organization anaphylaxis guidelines 2011"

First line therapy

1. Assess the state (ABCDE).

2. Call for help and stop exposure to the potential allergen. Stop all medications. During anesthesia, switch to another type of benefit (for example, inhalation anesthesia). Removal of stinger and/or insect (should not delay adrenaline administration). Do not induce vomiting or gastric lavage if food anaphylaxis is suspected.

3. Administer intramuscularly in the middle third of the thigh (in order to save time through clothing) epinephrine 0.5 mg for adults. For obese patients, long needles (38mm or 21G green) may be needed. Approximately 16-36% of patients (as indicated) may require a second dose of epinephrine after 5-15 minutes IM if IV access is not performed until then.
Do not waste time and do not attempt to administer IV epinephrine if the patient does not initially have venous access, is not connected to a cardiac monitor, and there are no qualified personnel nearby who can interpret ECG indicators and ready for cardiopulmonary resuscitation (IV bolus adrenaline is dangerous).
Even if all of the above conditions are met, intravenous epinephrine should be administered by pump (which is the safest) at a dilution of 1:100,000 with an initial average rate of about 1 µg/min, continuously titrated.
The range of adrenaline injection rates described in various sources is quite wide - from 1-10 µg/min. up to 5-15 mg/min. (maximum 50 mcg/min.). If a pump is not available, it is advisable to use a larger dilution (1:250,000) and titration by eye drop count. A similar solution is prepared by diluting 1 ml of epinephrine and 250 ml of a stock solution and has a concentration of 4 mg/ml. "Starting" speed in 1 µg/min. achieved quite easily even with intraosseous access.

4. Lay the patient down and raise the legs. Pregnant women are laid only on the left side. Leg elevation can improve perfusion and distribution of adrenaline, reduce central nervous system and myocardial hypoperfusion, stabilize cardiac return and output, and lead to greater peripheral venous filling, which improves the possibility of subsequent venipuncture.
The recumbent patient is more "convenient" for other various manipulations (transfer to a safe position during vomiting, to protect the airways during loss of consciousness, tracheal intubation and other manipulations).
A patient in a supine position on a gurney with restraints or on the floor requires less supervision from the staff to prevent him from falling (when assisted by one healthcare worker).
If the patient is conscious and can sit unaided (the sitting position is the most comfortable, for example, when respiratory symptoms prevail), blood pressure is not reduced, there are no signs of cerebral ischemia, it makes sense to keep the patient in this position until adrenaline is administered. In the future, guided by the clinic, he can be carefully transferred to the most comfortable position for him. In any case, the transfer of the patient from the supine position to the sitting position is not recommended due to the large number of adverse (fatal) consequences.

Second line therapy

5. 100% oxygen supply.

6. Venepuncture or provision of intraosseous access with infusion of 0.9% sodium chloride solution.
In the first 5-10 minutes, the pace for adults is 5-10 ml / kg / min., Then the pace can be changed based on the assessment of hemodynamics. The total volume of infusion in cases of persistent AS can be up to 1000-2000 ml.
Central venous catheterization in the early stages usually leads to unnecessary loss of time and can only be undertaken if venipuncture and/or intraosseous access is not possible/chronically unsuccessful and there are enough available personnel to continue adequate patient management without loss.
In severe cases, the volume of infusion, determined individually, taking into account all factors, can reach up to 5 liters / day. Installation of the Swan-Ganz catheter and invasive hemodynamic monitoring are certainly indicated in the management of patients with therapy-resistant AS.

7. Administration of H1- and H2-blockers (indicated for abdominal symptoms). The combination of H1- and H2-blockers is prognostically more favorable than the isolated use of one of them. It is not recommended to administer H1-blockers that affect hemodynamics (for example, pipolfen). Diphenhydramine 1 mg and ranitidine 50 mg are traditionally considered the optimal choice, which does not exclude the use of other drugs of the same groups.

8. Systemic GCS. Bolus is given. Recommended hydrocortisone 200 mg or prednisolone (up to 150 mg), methylprednisolone (up to 500 mg), dexamethasone (up to 20 mg). The introduction of systemic corticosteroids does not directly affect the course of AS, but probably prevents or reduces the risk of recurrence of anaphylaxis.

9. If adrenaline is ineffective (for example, in patients who have used beta-blockers for a long time), bradycardia, persistent arterial hypotension, the use of glucagon 50-150 mcg / kg IV for a minute, then 1-5 mg / hour per hour should be considered. /infusion if necessary.
Also (if indicated) vasopressin can be used, although evidence for this approach is limited (especially for abdominal syndrome).

10. Other vasopressors. There is no clear evidence of superiority of dopamine, dobutamine, norepinephrine, phenylephrine in combination with epinephrine or alone over epinephrine alone.
The recommended starting dose and rate of administration of vasopressors is standard and further titrated according to clinical response. This approach is especially indicated for patients with a history of taking beta-blockers.

11. With severe bronchospasm, inhalation can be used albuterol or adrenaline in appropriate doses. The effectiveness of aminophylline is doubtful, but it is traditionally used for stable hemodynamics by intravenous administration.

12 Anticholinergics are sometimes needed in "beta-blocked" patients. For example, atropine for patients with persistent bradycardia or in patients previously treated with ipratropium for epinephrine- and albuterol-resistant bronchospasm.

IV. Notes

1. The patient is defined as a child according to weight (less than 35-40 kg), but not according to age.

2. None of the existing randomized controlled trials (RCTs) on anaphylaxis is free from methodological problems, so the material presented is a kind of "average consensus" of the most significant sources.
Some sources provide data and recommendations, which in detail may not coincide with the material presented above. As a rule, they concern the following details:

2.1. The interval between injections of adrenaline (5 minutes versus 10-15 minutes). The need for a second dose of adrenaline is determined primarily by the course (clinic) of the process. The minimum allowed interval is 5 minutes.

2.2. The order of administration of drugs (for example, systemic corticosteroids are administered before antihistamines, and not vice versa).
Preparations of the "second line" in the presence of intravenous access are administered almost simultaneously. The difference of 60 seconds does not play a significant role if all previous activities have already been completed in full.

2.3. Choice among drugs in the same group (eg, hydrocortisone 200 mg is preferred over similar calculated doses of methylprednisolone or prednisone, or dexamethasone).
There are no RCTs that unequivocally prove the advantages of adequately calculated doses of certain systemic corticosteroids in the treatment of AS. The declared benefits of one or another systemic GCS are an extrapolation of experimental studies or clinical studies performed for a different reason, or a limited number of studies, all of which are not free from methodological problems or preferences of the authors and medical communities.
The choice of specific systemic corticosteroids used in the treatment of AS may also be determined by their availability, commercial and other factors.
In any case, the treatment of AS is systemic in nature and the prognosis at the first stage does not significantly depend on the type of systemic corticosteroids, provided an adequate equivalent dose is given.

2.4. Ultra-high (pulse therapy) or the maximum allowable therapeutic doses of systemic corticosteroids.
There is no clear evidence of the benefit of ultra-high doses of systemic corticosteroids in the treatment of AS, and there is no evidence to the contrary.
In the absence of evidence, the choice of the first dose is determined by national standards and the personal opinion of the physician, but, as a minimum, should correspond to the highest single therapeutic dose.

V. Separate groups of patients

1. Pregnancy and childbirth. AS during pregnancy exposes both mother and child to an increased risk of death or hypoxic/ischemic encephalopathy.
During the first, second, and third trimesters, potential causes are similar to those in non-pregnant women.
During labor and delivery, anaphylaxis is usually initiated by iatrogenic interventions (eg, oxytocin or antibiotics given to the mother to prevent beta-hemolytic streptococcal infection in newborns).
Anaphylaxis to medical latex has been described.
In extreme cases, with persistent hypotension and hypoxemia, a caesarean section may be necessary to save the life of the fetus.

2. Children.

2.1. Babies. Anaphylaxis is difficult to recognize in infancy because infants cannot describe their symptoms. Some of the signs of anaphylaxis are quite normal daily manifestations of the physiology of infancy (dysphonia after crying, regurgitation after feeding, and urinary incontinence).
Hypotension and tachycardia should be assessed in case of suspected AS, taking into account age.

2.2. Adolescents are prone to relapses of anaphylaxis due to their generally rash, risky behavior, inability/unwillingness to avoid known or suspected allergens, and lack of autoinjector skills.

2.3. Treatment.

2.3.1. Respiratory disorders.
Nasal cannulas are preferred for delivering humidified warm oxygen. Non-invasive respiratory support in CPAP mode is the initial method of choice, which does not preclude endotracheal intubation and invasive mechanical ventilation methods.
Inhaled albuterol (2.5–5 mg) and/or ipratropium bromide may be useful in severe bronchospasm refractory to adrenaline.
Although the combination of ipratropium and albuterol has been effective in the treatment of asthma in children, this combination has not been studied in anaphylaxis.
The aerosol route of epinephrine administration has been used to treat stridor secondary to laryngeal edema, but has not been studied in anaphylaxis.

2.3.2. Adrenalin.
The method and concentration are similar to those in adults.
Dose for children 0.3 mg (dose calculated as 0.01 mg/kg or approximately 0.15 mg for children less than 25 kg; 0.3 mg for children 25-45 kg; full dose of 0.5 mg for children weighing more than 45 kg, regardless of age).
Subcutaneous administration is not recommended due to potential arrhythmias. The interval between intramuscular doses is the same as in adults.

2.3.3. Treatment of hypotension.
Patients who do not respond to positioning and adrenaline should receive intravenous crystalloids (Ringer's lactate or isotonic sodium chloride solution) at a dose of 10-30 ml/kg in the first hour (bolus administration is possible).
In refractory cases, higher doses may be needed, administered under the control of hemodynamics, diuresis and laboratory tests.
Glucagon may help with refractory disease in patients taking beta-blockers. In children, the introduction of 20-30 mcg / kg (no more than 1 mg / day) is indicated intravenously for 5 minutes, and then in a maintenance infusion with titration to a clinical effect at a rate of 5-15 mcg / min.

Patients who do not respond to infusion should receive vasopressors.
Epinephrine or epinephrine (0.1-1 mcg/kg/min IV) should be considered as the initial vasopressor in children. Doses less than 0.3 mcg/kg/min. will have more pronounced β-adrenergic activity, while α-adrenergic activity becomes more pronounced at higher doses.
Dopamine (2-20 mcg/kg/min IV) may be used in addition to epinephrine. An increase in α-activity was observed at high doses.
Norepinephrine (0.1-2 mcg/kg/min IV) is the drug of choice in children who do not respond to adrenaline.

2.3.4. Antihistamines.
Second generation H1 blockers (eg, cetirizine, loratadine) have not been studied in anaphylaxis.
The following drugs are recommended:
- diphenylhydramine parenterally 0.25 -1 mg / kg (but not more than 50 mg / day);
- ranitidine parenterally 0.25-1 mg/kg (but not more than 50 mg/day).

The dose of chlorphenamine depends on age:
- over 12 years and adults: 10 mg IM or IV slowly;
- over 6-12 years: 5 mg IM or IV slowly;
- more than 6 months-6 years: 2.5 mg IM or IV slowly;
- less than 6 months: 250 mcg/kg IM or IV slowly.

There is little evidence to support the routine use of H2 blockers (eg, ranitidine, tagamet) in initial treatment anaphylactic reactions, so their use is indicated for severe abdominal syndrome.

2.3.5. Corticosteroids may help reduce or prevent biphasic anaphylaxis. The choice of a particular drug is determined by the preferences of the doctor.
There are no published studies comparing, for example, dexamethasone with other corticosteroids in the treatment of anaphylaxis. However, based on its use in other allergic conditions, a dexamethasone dose of 0.15-0.6 mg/kg IV would be most appropriate.
Prednisolone is calculated as 2 mg/kg, other systemic corticosteroids are calculated as an equivalent dose. The dose of systemic corticosteroids can be repeated after 6 hours.

The dose of hydrocortisone for adults and children depends on age:
- over 12 years and adults: 200 mg IM or IV slowly;
- over 6-12 years: 100 mg IM or IV slowly;
- more than 6 months-6 years: 50 mg IM or IV slowly;
- less than 6 months: 25 mg IM or IV slowly.

3. Middle-aged and elderly patients are at increased risk of severe or fatal anaphylaxis due to known or subclinical cardiovascular disease and the drugs used to treat it.
In patients with ischemic heart disease, the number and density of mast cells in the myocardium increase in its affected areas and in atherosclerotic plaques. During anaphylaxis, histamine, leukotrienes, PAF, and other mediators released from myocardial mast cells contribute to the narrowing and spasm of the coronary arteries.
Anaphylactic shock can manifest itself in such patients in the form of an acute coronary syndrome (angina pectoris, myocardial infarction, arrhythmias) both before and after adrenaline injection.

VI. Further management

Depending on the severity of the reaction and taking into account the likely biphasic course of anaphylaxis (up to 20% of patients), after stabilization of the condition, the patient should be observed and monitored for 10-24 hours. Longer follow-up is indicated in the development of complications, for example, from adrenaline (up to 3 days) and is associated with monitoring cardiac activity and carrying out the necessary procedures for differential diagnosis.
Depending on the patient's condition, a further course of antihistamines, systemic corticosteroids, bronchodilators can be continued by their intramuscular, inhalation and oral administration.
Treatment (according to indications) can be supplemented with sedatives. Diphenhydramine can be replaced by hydroxyzine.
Therapy with antihistamines and systemic corticosteroids can be continued at home for another 2-3 days.

Forecast

Due to the blurring of the concept of anaphylaxis in clinical practice, the true rates of persistent disabling complications and mortality are unknown, but anaphylaxis is regarded as a potentially fatal condition.
Although anaphylaxis without hemodynamic disturbances is considered to be a milder condition than anaphylactic shock, there are known cases of death from asphyxia in the absence of significant hemodynamic changes.

Mortality in anaphylactic shock varies significantly and in some cases reaches 20-30%.

Unfavorable signs:
- asthma;
- heart disease;
- the rapid development of the clinic (especially arterial hypotension);
- resistance to therapy (adrenaline, infusion, bronchodilators);
- long-term previous therapy with beta-blockers;
- biphasic flow;
- lack of training of medical personnel, the patient himself and his relatives;
- delay in providing assistance for any other reason.

Hospitalization

Emergency hospitalization is required to the nearest medical facility in the intensive care unit.
After recovering from anaphylactic shock, the patient can be hospitalized in a specialized department (allergology, immunology, pulmonology, gastroenterology, therapy).
The time of inpatient treatment has not been determined. Cases of patients staying in the immunology department for up to 3 weeks are described.

Prevention

Primary prevention
No laboratory methods and instrumental research cannot reliably indicate the possibility of developing anaphylactic shock, if no episodes of anaphylaxis have been noted before. Therefore, a history taking and a qualitative examination of the patient that reveals significant risk factors should be performed at any routine examination, especially if it precedes the prescription of drugs or surgery.

Secondary prevention

Decrease in lethality:

1. Patients with a history of anaphylaxis after discharge from the hospital should be trained in the use of an auto-injector, should wear a medical identification tag in the form of a bracelet or necklace, indicating anaphylaxis and its causes. Relatives of the patient should also be trained in first aid for anaphylaxis. Appropriate notes should be made in the patient's outpatient card.

2. Decreasing mortality in healthcare facilities does not depend on the speed of resuscitators, but on the training of all medical staff in the algorithm for providing care for anaphylaxis and accessibility necessary medicines and equipment.

Relapse prevention:

1. Patients should be screened for potential triggers Trigger - trigger, provocative substance or factor
anaphylaxis and further avoid contact with potential allergens, including allergens related to the so-called "cross" (for food-related anaphylaxis, diet and a pause between eating and physical activity of 6-12 hours are necessary).

2. Promising therapies include allergen-specific and non-allergen-specific. Non-specific therapies for food-induced anaphylaxis include monoclonal human anti-IgE antibodies, which increase the threshold dose to induce anaphylaxis, for example, in individuals with peanut allergy.
Allergen-specific therapy includes oral, sublingual and skin immunotherapy (desensitization) with recombinant proteins.

3. The prophylactic administration of antihistamines and systemic corticosteroids in patients with episodes of unclear anaphylaxis in history before elective surgery has not been studied by anyone. The choice or refusal to prescribe these medications remains the prerogative of the doctor. The minimum effective course is presumably 2-3 days when taken orally.

Information

Sources and literature

1. "Emergency treatment of anaphylactic reactions .Guidelines for healthcare providers" Working Group of the Resuscitation Council (UK), jan 2008/ Annotated with links to NICE guidance July 2012 /Review Date: 2013
2. Anaphylaxis and Hypersensitivity Reactions/ editor Mariana C. Castells, New York: Humana Press, c/o Springer Science+Business Media, LLC, 2011
3. Finnish Medical Society Duodecim. Blood transfusion: indications, administration and adverse reactions. EBM Guidelines, Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2011
4. Guideline on the investigation and management of acute transfusion reactions Prepared by the BCSH Blood Transfusion Task Force, 2012
5. Nayyar, John V Peter, Roop Kishen, S Srinivas Critical Care Update 2010, New Delhi: Jaypee Brothers Medical Publishers, 2011
6. Drannik G.N. Clinical immunology and allergology, K .: Polygraph-Plus, 2010
7. Konyaeva E.I., Matveev A.V., Rusanova L.A. Anaphylactic and anaphylactoid reactions in pharmacotherapy. Guidelines for doctors, Simferopol, 2009
8. Guide to emergency medical care, M .: GEOTAR-Media, 2007
9. Guidelines of the Anesthetists Association of Great Britain and Ireland. Suspected Anaphylactic Reactions Associated with Anesthesia, 2008
10. "2012 Update: World Allergy Organization Guidelines for the assessment and management of anaphylaxis" Simons FE, Ardusso LR, Bilò MB, Dimov V, Ebisawa M etc, "Current Opinion in Allergy and Clinical Immunology" journal, No. 12(4), 2012
11. "Adrenaline for resuscitation: now even more questions than answers" Michael Bernhard, Bernd W. Bottiger and Peter Teschendorf, European Journal of Anaesthesiology, no. 30, 2013
12. "Anaphylaxis as an adverse event following immunization in the UK and Ireland" Erlewyn-Lajeunesse M., Hunt L.P., Heath P.T., Finn A., "Archives of Disease in Childhood" journal, jan 2012
13. "Anaphylaxis in Children: Current Understanding and Key Issues in Diagnosis and Treatment" Chitra Dinakar, "Current Allergy and Asthma Reports" journal, No. 12(6), 2012
14. "Anaphylaxis: the acute episode and beyond" F Estelle R Simons, Aziz Sheikh, "British Medical Journal", feb 2013
15. "Customizing Anaphylaxis Guidelines for Emergency Medicine" Richard Nowak, Judith Rosen Farrar, Barry E. Brenner, Lawrence Lewis, Robert A. Silverman etc, "Journal of Emergency Medicine", No. 45(2), 2013
16. "Hypersensitivity Reactions to Blood Components" (Allergy Committee of the French Medicines and Healthcare Products Regulatory Agency) PM Mertes, A Bazin, F Alla etc, "Journal of Investigational Allergology and Clinical Immunology", Vol. 21(3), 2011
17. "Immunological Complications of Blood Transfusion" Clare Taylor, Cristina Navarrete, Marcela Contreras, "Transfusion Alternatives in Transfusion Medicine" journal, No. 10(3), 2008
18. "Prevention and Control of Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2011, aug 2011
19. "The diagnosis and management of anaphylaxis practice parameter: 2010 update" Lieberman P, Nicklas RA, Oppenheimer J, Kemp SF, Lang DMJ etc, "Journal of Allergy and Clinical Immunology", No. 126(3), 2010
20. "World Allergy Organization Anaphylaxis Guidelines: 2013 update of the evidence base" Simons FE, Ardusso LR, Dimov V, Ebisawa M, El-Gamal YM etc, "International Archives of Allergy and Immunology" journal, No. 162(3), 2013
21. "World Allergy Organization Guidelines for the Assessment and Management of Anaphylaxis" F. Estelle R. Simons, MD, FRCPC, Ledit R. F. Ardusso, MD, M. Beatrice Bilò etc, "World Allergy Organization Journal", No. 4(2), 2011
22. http://www.anaphylaxis.ru/sprav/vakzina.html
23. http://emedicine.medscape.com
    1. "Anaphylaxis" S Shahzad Mustafa, dec 2013 -
    2. "Pediatric Anaphylaxis" Jeffrey F Linzer Sr, dec 2013 -

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Anaphylactic shock is a dangerous rapidly developing pathological reaction of the body to an allergen. This condition can be very Negative consequences. And this article will therefore tell you about the pathogenesis of anaphylactic shock in children and adults, give clinical recommendations and tell you what first aid kit you need to have if you are overtaken by anaphylactic shock.

Features of the disease

Anaphylactic shock (anaphylaxis, allergic shock) is an acute, rapidly developing pathological reaction of the body in response to an attack (shock - shock) of allergens, in which all systems and organs experience extremely pronounced painful changes, often incompatible with life (everyone has 5 - 10 patient). The speed of all processes characteristic of a banal allergy, in the case of a shock effect, accelerates, and their severity increases tenfold.

Are exposed to:

• all organs and ways of breathing, vessels and capillaries;
• brain, heart;
• organs of the gastrointestinal system;
• skin and mucous membranes.

The highest frequency of this allergic reaction immediate type occurs in women, boys and young men.

The video below will tell you what anaphylactic shock is:

Children

Anaphylaxis is of particular danger to the child's body due to the underdevelopment of many systems and organs, the protective function, anatomical and physiological features. For example, laryngeal edema in a child is a critical condition, since the respiratory lumen is extremely small and swelling of the mucosa to a thickness of only 1 mm will easily block the access of air to the newborn and infant.

At this age, vaccination, drugs often provoke an acute allergic reaction. But if in adults, shock usually occurs when allergens enter the blood again, then in children, anaphylaxis can develop upon first contact with an allergic shock provocateur, if the mother used a certain medication during pregnancy and breastfeeding, and it got into the placenta or milk through the placenta or milk. baby's blood. Moreover, neither the dose nor the route of administration pharmacological agent do not matter if the child is already sensitized (has an increased sensitivity to a particular substance).

In addition, it is in children that anaphylaxis to foods is more likely to develop.

Pregnancy

Pregnancy also creates particular vulnerability for the expectant mother and fetus. With overloads experienced by the heart and vascular system during anaphylaxis, the likelihood of miscarriage, early placental abruption, premature birth and intrauterine death is very high. The pregnant woman herself is also at risk of catastrophic bleeding, respiratory and.

Read about the types and forms of anaphylactic shock below.

Classification

According to flow patterns

Classification according to the forms of the course of anaphylactic shock (AS) is tied to the key signs of a disorder of specific systems and target organs, to which the main aggression of allergens is directed.

Downstream, anaphylaxis is divided into forms:

1. Typical. It occurs most often, accompanied by violations of the functions of blood vessels, organs and respiratory tract,.
2. Hemodynamic. Accompanied by impaired blood circulation, insufficiency of the functioning of the myocardium, heart vessels.
3. Asphyxic, with the dominance of manifestations of acute respiratory failure, edema and spasms of the respiratory tract, reaching the degree of asphyxia (suffocation).
4. Abdominal or gastrointestinal form with symptoms of acute poisoning, " acute abdomen”, diseases of the stomach, intestines.
5. cerebral, with characteristic lesions of the central trunks of the nervous system, cerebral vessels, developing to cerebral edema.
6. Form of AS provoked physical overload.

According to the severity of the course

The severity of the pathology according to the criteria:

The severity of the shock determines the timing of the onset of the first symptoms. The sooner the symptoms begin to appear from the moment the allergen enters the body, the more severe the manifestations of anaphylaxis.

By type of flow

Classification of AS by flow type:

Read more about the causes of anaphylactic shock.

Causes

Development mechanism

Stage I

Sensitization (an abnormal increase in sensitivity to a specific allergen substance).

The initial hit of the allergen is perceived by the immune system as the penetration of a foreign agent, which produces special protein compounds - immunoglobulins E, G, after which the body is considered sensitized, that is, ready for a sharp allergic reaction when the allergen is reintroduced. Immunoglobulins are fixed on immune (mast) cells.

Stage II

Directly - an anaphylactic reaction.

When the allergen enters the blood again, immunoglobulins immediately come into contact with it, after which specific substances are released from the mast cells that regulate allergic and inflammatory reactions, the main of which is histamine. It causes edema, vasodilation - and, as a result, a drop in pressure, impaired breathing. In anaphylactic shock, histamine is released simultaneously and in large volume, which leads to catastrophic disruption of the work of all organs.

With anaphylaxis, a similar pathological process, if medical intervention does not occur, develops rapidly, irreversibly leading to death.

Main reasons

Among the numerous reasons for the development of AS, there are, firstly, the administration of drugs, including:

• antibiotics (penicillin, aminoglycosides, trimethoprim, vancomycin);
• Aspirin, other non-hormonal anti-inflammatory drugs (NSAIDs);
• ACE inhibitors (drugs for hypertension - Fosinopril, even if the medicine has been taken for several years before);
• sulfonamides, iodinated preparations, B vitamins;
• plasma substitutes, iron preparations, a nicotinic acid, immunoglobulins.

With an intravenous infusion of the drug, the reaction develops after 10-15 seconds, with an intramuscular injection - after 1-2 minutes, when taking tablets and capsules - after 20-50 minutes.

Risk factors:

1. Available allergic diseases(, allergic rhinitis)
2. chronic diseases respiratory organs including asthma, chronic pneumonia, bronchitis, bronchial obstruction).
3. Diseases of the heart and blood vessels
4. Presence of anaphylactic reactions.
5. Concomitant treatment of the patient with the following drugs:
   • beta-blockers (the reaction of the respiratory tract to histamine, bradykinin increases and the effect of adrenaline used to remove the patient from shock decreases).
   • MAO inhibitors (suppress the enzyme that breaks down adrenaline, thus enhancing side effect adrenaline).
   • ACE inhibitors (may cause swelling of the larynx, tongue, pharynx with the development of suffocation, "kapoten cough").

Signs of anaphylactic shock

Symptoms

The initial manifestations with the rapid development of anaphylaxis are observed already in the first seconds after the penetration of the allergen into the blood. This usually happens when the drug is injected into a vein. A typical increase in symptoms is in the range of 5 to 40 minutes.

But often there is a two-phase course of anaphylactic shock, when, after subsiding all the signs against the background of intensive treatment, a day or three later, a second wave of anaphylaxis can suddenly begin.

The basic symptoms of anaphylactic shock are often combined or manifest in a complex manner - in accordance with the forms of AS:

Diagnostics

If episodes of an anaphylactic reaction have never been determined in a patient before, then studies are not able to predict its manifestation in the future, that is, to predict its development. However, the probability of its occurrence to one degree or another can be predicted:

• absolutely everyone who suffers from any form of allergy;
• in people whose relatives (especially parents) experienced a similar experience of anaphylaxis.

Since anaphylaxis is a condition in which all manifestations increase very quickly, the diagnosis is most often made already during the development of the pathology, based on the rate of development of symptoms, and even more often after treatment or death. Since delay in such a situation leads to the death of the patient, a detailed study of each symptom at this moment is impossible and simply - extremely dangerous.

The danger of a false diagnosis

On the other hand, due to lack of time and lack of professionalism, false diagnoses are often made.

• For example, with the development of gastrointestinal (abdominal form) anaphylaxis, all the signs are very similar to the symptoms of acute poisoning, appendicitis, pancreatitis, biliary colic.
• In the hemodynamic form, with its severity of heart pain and manifestations of insufficiency, a person is diagnosed with "".
• Spasms of the bronchi, and even swelling of the larynx, are attributed to signs of an asthmatic attack, and brain and neurological disorders are attributed to, and other diseases that have nothing to do with anaphylactic shock.

Such false diagnoses are deadly for the patient, since the time for proper treatment it just doesn't stay.

Therefore, if, after a glass of orange juice, severe pain behind the sternum suddenly occurs, this immediately indicates the development of anaphylaxis. And don't wait for any other signs.

Actions for AS

Problem Identification

Identification of the aggressor allergen that caused anaphylactic shock is a very important step that should be included directly in the treatment of pathology. If the patient has not experienced allergic reactions, special studies are carried out. They are able to confirm the diagnosis of allergization of the body as a whole, as well as the causative allergen in a particular case of anaphylaxis.

Among them are:

• skin, skin, application tests (Patch-test);
• a blood test for the presence of immunoglobulins E (IgE), which are responsible for allergic reactions;

In order to guarantee the safety of the patient's health in the event of a sharp response to an allergy provocation, all studies are carried out with a high degree of caution. The safest is the radioimmunological method during the allergen sorbent test (RAST), which most accurately determines the anaphylactic allergen without affecting the structure of the body.

Safety is ensured by conducting an analysis outside the patient's body. In the blood taken from the patient, alternately add different kinds allergens. If, after the next interaction of the blood with the allergen, an abnormal amount of antibodies is released, this indicates this allergen as the cause of the anaphylactic reaction.

This video will tell you about first aid for anaphylactic shock:

Treatment

In the hospital - in the intensive care unit and the intensive care unit, the main treatment of anaphylactic shock is carried out.

Basic principles

Basic principles of treatment of anaphylactic shock:

1. Elimination of serious dysfunctions in the work of the heart muscle, blood vessels, respiratory and nervous systems.
2. Prevention of a sudden drop in pressure and the development of coma.
3. Prevention, brain, asphyxia, cardiac arrest.
4. Removal of life-threatening edema of the larynx, trachea, bronchi.
5. Suppression of further releases of histamine, bradykinin, kallikrein and removal of allergen substances from the blood.

About whether adrenaline is administered in case of anaphylactic shock and what other drugs will be needed, we will tell further.

Activities and medicines

1. Intramuscular injections of Adrenaline (epinephrine) 0.1% every 10-15 minutes, 0.2-0.8 ml. When calculating children's doses, the rate of 0.01 mg (0.01 ml) per kilogram of the baby's weight is taken into account. If a positive reaction does not occur, do intravenous administration 1 ml epinephrine in 10 ml NaCl solution - slowly - 5 minutes to prevent myocardial ischemia. Or 1 ml of medicine in 400 ml of NaCl through a dropper, which is more rational.
2. Infusion of fluids to prevent coma: 1 liter of NaCL solution, then -0.4 liters of Polyglucin. Initially, a jet injection of up to 500 ml is provided for 30-40 minutes, later - through a dropper. It is believed that colloidal solutions fill the vascular bed more actively, however, crystalloid liquids are safe, since dextrans themselves can cause anaphylaxis.
3. Glucocorticoids.
   • Hydrocortisone in a muscle or vein: adults from 0.1 to 1 gram. For children, intravenous injections of 0.01 to 0.1 grams.
   • : 4 - 32 mg intramuscularly, daily dose for intravenous injection 3 mg per kilogram. After removing the patient from an acute condition, Dexamethasone is prescribed in tablets in a daily dose of up to 15 mg. Children's doses are calculated by the weight of children: from 0.02776 to 0.16665 mg per kilogram.
   • : 150 - 300 mg once intramuscularly, infants up to a year per kilogram of weight 2 - 3 mg, from 1 year to 14 years, 1 - 2 mg.
4. Means for restoring respiratory patency and relieving bronchospasm, suppressing histamine releases.
   • 2.4% 5 - 10 ml intravenously. Drip administration provides a dose of 5.6 mg per kilogram (20 ml of the drug is diluted in 20 ml of 0.9% NaCl and 400 ml of saline). The highest doses per day per kilogram of weight: 10-13 mg, for children from 6 years old - 13 mg (0.5 ml), from 3 to 6, 20-22 mg (0.8-0.9 ml). Carefully use Eufillin in the last trimester of pregnancy, since tachycardia is possible in the mother and fetus.
   • In addition to Eufillin, Aminophylline, Albuterol, Metaproterol are used.
5. Medicines to activate the work of the heart. Atropine 0.1% subcutaneously 0.25 - 1 mg. Pediatric single doses are prescribed by weight and age in the range of 0.05 - 0.5 mg.

1. Medicines that prevent pressure drops and increase cardiac output.
   • Dopamine. Applied intravenously after dilution in a solution of glucose 5% or sodium chloride. Adults (per kilogram of weight per minute) from minimum dosages of 1.5 - 3.5 mcg (infusion rate 100 - 250 mcg / min) to 10.5 - 21 mcg (750 - 1500 mcg per minute). For children over 12 years of age, the highest dose per kilogram is 4-8 mcg (per minute).
   • In pregnant patients, Dopamine is used only when life is threatened for the mother; no teratogenic (disfiguring fetus) effect of Dopamine has been identified. Breast-feeding stop.

1. Antihistamines, which stop the release of allergic provocateur substances into the blood, eliminate itching, swelling, and hyperemia. It is rational to prescribe after the restoration of the circulating blood volume, since they can lower the pressure.
   • Oxygen therapy. Helps with growth oxygen starvation tissues and bronchospasm.
   • Hemosorption- a special extrarenal technique for removing allergens from the blood when passing it through sorbents.

   All patients who survived anaphylaxis should be observed in the hospital for up to 2-3 weeks, because of the likelihood of recurrent anaphylaxis and late complications from the heart, blood vessels, respiratory and urinary systems.

   Therefore, in the hospital several times they do:

   • analysis of blood, urine;
   • study of indicators of urea, creatinine in the blood;
   • or ;
   • study of feces for the Gregersen reaction.

   Disease prevention

   To reduce the risk of developing AS in people who are at high risk of exposure to an allergen, you should:

   • be sure to have a set of emergency medicines (we wrote about it separately):
     • adrenaline solution;
     • Prednisolone in ampoules;
     • Ventolin, Salbunanol;
     • Suprastin or Tavegil or Diphenhydramine (in ampoules)
     • tourniquet
   • be able to use an automatic syringe for injection of adrenaline (Epi-pen, Allerjet);
   • avoid insect bites (cover open places, do not eat sweets and ripe fruits outside the home), use special repellents;
   • correctly evaluate the components in the products used in order to avoid the penetration of allergens through the stomach;
   • at work, avoid contact with industrial chemicals, inhalation and skin allergens;
   • do not use β-blockers at the risk of developing severe anaphylaxis, replacing them with drugs from another group;
   • when conducting studies using radiopaque substances, pre-injection of Prednisolone
   • make tests for allergies from medicinal and other substances;
   • choose medicines in tablets, not in injections;
   • always have a “passport” (card, bracelet, pendant) with you with information about allergic diseases and drugs that help with AS.

   Pro possible complications after such an allergic reaction as anaphylactic shock, read on.

   Complications

   • Severe complications can be diagnosed:
   • Glomerulonephritis
   • Intestinal and stomach bleeding
   • Cardiac pathologies, including myocarditis
   • Bronchospasm and pulmonary edema;
   • Edema and bleeding in the brain

   If help is delayed, the pulse becomes weak, the person loses consciousness, and there is a high risk of death.

   Forecast

   The prognosis is favorable only in case of immediate medical care when making an accurate diagnosis and emergency hospitalization of the patient.

   According to statistics, almost 10% of people die with anaphylactic shock.

   However, even stopping the acute state of anaphylaxis with drugs does not mean that everything ended successfully, since there is a high probability of a secondary drop in pressure and the development of anaphylaxis (usually within 3 days, but a longer period also occurs).

   This video will tell you what to do when anaphylactic shock occurs:

Anaphylactic shock is the most severe manifestation of an allergic reaction. Anaphylaxis develops rapidly, sometimes doctors do not have time to help the patient, and he dies from suffocation or cardiac arrest.

The outcome of shock depends on the timely assistance provided and the correct actions of the doctor.

What is anaphylaxis

Anaphylaxis (anaphylactic shock)- this is an instant type, which is expressed in a sharp increase in the body's sensitivity to both the re-introduced allergen and the substance that first entered the body. The reaction develops at a rate from a few seconds to a couple of hours.

For the first time, the definition of the concept was given at the beginning of the 20th century by the Russian scientist Bezredka A.M. and the French immunologist Charles Richet, who received the Nobel Prize for his discovery.

The severity of the course of anaphylaxis is not affected by either the way the allergen enters or its dose. Shock can develop from a minimal amount of medication or product.

Most often, anaphylaxis manifests itself as a reaction to drugs, in this case, the lethal outcome is 15-20%. Due to the increase in the number of people suffering from in recent years, there has been an increase in the number of cases of anaphylaxis.

How does pathology develop?

The reaction of the body during anaphylaxis goes through three successive stages:

• immunological reaction;
• pathochemical reaction;
• pathophysiological response.

Immune cells come into contact with allergens, releasing antibodies (G. E. Ig). Due to the effects of antibodies in the body, histamine, heparin and other inflammatory factors are released. These inflammatory mediators are distributed to all organs and tissues. As a result, there is a thickening of the blood, a violation of its circulation.

First, the peripheral circulation is disturbed, then the central circulation. As a result of poor blood supply to the brain, hypoxia occurs. The blood coagulates, heart failure develops, the heart stops.

The reasons

The main cause of anaphylactic shock is the ingestion of an allergen. There are several main groups of allergens.

Medicines. Usually anaphylaxis is provoked by the following types of drugs:

• antibiotics;
• contrasts;
• hormonal agents;
• sera and vaccines;
• non-steroidal anti-inflammatory drugs;
• muscle relaxants;
• blood substitutes.

• Adrenaline Solution. It is administered intravenously with the help of droppers, constantly monitoring the pressure. The tool has a complex effect, normalizes pressure, eliminates pulmonary spasm. Adrenaline suppresses the release of antibodies into the blood.
• Glucocorticosteroids(dexamethasone, prednisone). They inhibit the development of immune reactions, reduce the intensity of the inflammatory process.
• Antihistamines(claritin, tavegil, suprastin). First they are administered by injection, then they switch to. These drugs inhibit the action of free histamine, which blocks its effects. Antihistamines should be administered after normalization of pressure, as they can lower it.
• If the patient develops respiratory failure, then he is administered methylxanthines(caffeine, theobromine, theophylline). These drugs have a pronounced antispasmodic effect, relax smooth muscles, reduce bronchospasm,
• To eliminate vascular insufficiency, crystalloid and colloidal solutions(ringer, gelofusin, riopoliglucin). They improve blood microcirculation, reduce its viscosity.
• Diuretic (diuretic) drugs(furosemide, minnitol) is used to prevent swelling of the lungs and brain.
• tranquilizers(Relanium, Seduxen) is used for severe convulsive syndrome. They eliminate the feeling of anxiety, fear, relax muscles, normalize the functioning of the autonomic nervous system.
• Hormonal drugs local action (prednisolone ointment, hydrocortisone). They are used for skin manifestations of allergies.
• Absorbable ointments(heparin, troxevasin). Used for resorption of cones in places of bites.
• Inhalations humidified oxygen to normalize lung function and eliminate symptoms of hypoxia.

Treatment in the hospital lasts 8-10 days, then the patient is monitored to prevent complications.

Possible Complications

Anaphylactic shock never goes unnoticed. The consequences of the disease may still persist long time. There may also be delayed complications.

The main complications of anaphylaxis are:

• Pain in muscles, joints, abdomen.
• Dizziness, nausea, weakness.
• Heart pain, shortness of breath.
• Prolonged pressure drop.
• Deterioration of the intellectual functions of the brain due to hypoxia.

To eliminate these consequences, the patient is prescribed:

• nootropics (cinnarizine, piracetam);
• cardiovascular drugs (mexidol, riboxin).
• drugs that increase blood pressure (norepinephrine, dopamine).

Late complications of anaphylactic shock are very dangerous, they can lead to death or disability.

Late complications include:

• hepatitis;
• myocarditis;
• kidney failure;
• glomerulonephritis (malignant degeneration of the kidneys);
• diffuse (extensive) damage to the nervous system;
• bronchial asthma;
• recurrent urticaria;
• systemic lupus erythematosus.

To prevent serious consequences in the course of treatment, the functioning of the heart, kidneys, and liver is monitored. The patient is recommended to consult an immunologist and immunotherapy.

Causes of death from anaphylaxis

In anaphylactic shock, conditions develop directly life threatening patient. Death occurs in 2% of cases due to untimely assistance.

Causes of death due to anaphylaxis:

• swelling of the brain;
• pulmonary edema;
• airway obstruction.

Prevention

Prevention of anaphylactic shock is primary and secondary. The primary is aimed at preventing the development of any allergy, the secondary is aimed at preventing the recurrence of shock.

Methods of primary prevention:

• giving up bad habits (alcohol and smoking);
• caution in taking medications, any drugs are taken as prescribed by a doctor, you can not take several drugs at the same time;
• reducing the consumption of foods with preservatives;
• strengthening immunity;
• timely treatment of any type of allergy;
• avoiding snake bites, insects;
• an indication of the drugs that caused the allergy on the title page of the medical record.

With a tendency to allergies, it is desirable before taking medicines.

To prevent the recurrence of shock, the patient must observe the following safety measures:

• regularly clean the premises to remove dust, mites;
• do not have pets and do not contact them on the street;
• remove soft toys and extra items from the apartment so that dust does not collect on them;
• during the flowering period of plants, wear sunglasses, take antihistamines, avoid visiting places with a large number of allergenic plants;
• follow a diet, exclude foods that cause allergies;
• do not take drugs that cause a pathological reaction;
• don't swim in cold water cold allergy sufferers.
• on the medical card there should be a mark that the patient has experienced anaphylactic shock.

Anaphylactic shock is a deadly condition. It appears unexpectedly and develops rapidly. The prognosis depends on the timely provision of assistance and the right therapy. It is important for recovery general state patient health and the absence of chronic diseases.

28.07.2017

An allergic reaction gives the patient a lot of inconvenience, and if it leads to anaphylactic shock, then this poses a serious threat to human life.

Allergic shock is a severe manifestation of allergy, which is activated at the time of repeated interaction with the irritant.

The danger of the body's reaction to what is happening lies in the fact that 20% of such cases turn into a fatal outcome.

And an anaphylactic reaction occurs regardless of the type and dosage of the allergen, as well as the speed of its penetration into the body.

Anaphylactic shock in 20% of cases causes the death of the patient

Features of allergic shock

Anaphylactic shock is an organism to an external or internal stimulus that develops very quickly and poses a huge threat to human health and life.

Anaphylaxis develops very rapidly, within a few hours after contact with the allergen. The reaction can occur both in a few seconds and in a couple of hours, so it is important to provide emergency care quickly, otherwise death occurs.

Allergic shock can occur in any person with allergies, regardless of age and gender. But the first anaphylactic cases were seen not in humans, but in dogs. When this condition occurs, internal organs and body systems undergo negative changes.

Coming into contact with the allergen, antibodies that are responsible for the protective functions of the body contribute to the production of special substances, which disrupts the blood flow and the operation of all systems.

Due to the violation of blood circulation in all internal organs, there is a lack of nutrition, for example, oxygen, which leads to a hunger strike, especially the brain. At the same time, there is a drop in blood pressure, dizziness appears, which leads to loss of consciousness.

The condition that occurs in a patient during an allergic shock means a malfunction of the immune system, therefore, after providing first aid, you need to start restoring and strengthening work immune system.

Causes of anaphylaxis

Allergy occurs as a result of direct contact of the body with protein compounds of a different nature, is a kind of immune reaction. This immune reaction of the body can be varied: from a small rash on the skin to the onset of a dangerous condition, like an allergic shock.

The main reason for the development of anaphylactic shock is repeated contact with an irritant, which most often acts as a drug.

The most common causes of anaphylactic shock are:

1. Some insect bites. Some people have a severe allergic reaction to the sting of insects such as wasps, bees and hornets. And if several insect bites occur at the same time, this almost always leads to the development of allergic shock. And even if for the first time after an insect bite only a slight swelling and redness of the skin appeared, then during the next contact with the allergen, the symptoms will be more pronounced, even if this contact occurs after several years.
2. Bites of some animals. Allergic shock can be caused by any representative of the animal world, which, when bitten, releases poison into its victim. Such animals include spiders, snakes, some types of frogs;
3. Medications. People prefer self-administration of medications, without consulting a doctor. Self-medication can both cure and cripple. Incorrect medication can lead to severe and unforeseen consequences. To medicines that can cause allergic shock include:

• antibiotics: tetracycline and penicillin;
• anesthetics that are used during operations;
• non-steroidal anti-inflammatory drugs;
• inhibitors that are used to treat hypertension;
• hormones;
• vaccines, serums;
• enzymes and muscle relaxants;
• food products. Most people consume fast food and poor quality foods that contain a huge amount of GMOs, which causes a lack of vitamins and minerals in the body, which leads to serious disruption. human body. And besides this, some foods lead to the development of an allergic reaction. These highly allergenic foods include:

1. seafood;
2. dairy;
3. citrus and some other fruits;
4. nuts;
5. chocolate.

Allergic shock most often occurs due to repeated exposure to the allergen.

There are some more factors that lead to the development of the state of anaphylactic shock:

• introduction of radiopaque substances into the body;
• during a blood transfusion;
• conducting skin tests for allergies;
• reaction to cold
• strong physical activity;
• repeated exposure to household allergens: cosmetics, dust, plant pollen, chemicals.

Varieties of allergic shock

Anaphylaxis can be classified as follows:

1. according to the severity of the course: mild, moderate and severe course of the disease;
2. according to the nature of the flow:

• benign;
• protracted;
• acute malignant;
• abortive;
• recurrent;

1. according to the speed of development: fast (up to 3 minutes), acute (no more than 30 minutes), subacute (more than half an hour);
2. according to the shape of the flow:

• typical. The most common form, which is accompanied by a violation of the functioning of organs and blood vessels, is swelling of the skin;
• hemodynamic. The cardiovascular system is affected;
• asphyxic. There is acute respiratory failure, there is a violation of the functions of the respiratory tract;
• abdominal. There are symptoms of an acute form of poisoning, pain in the stomach;
• cerebral. The central nervous system is affected, which leads to cerebral edema.

Anaphylaxis is a serious threat to the life of the patient

The mechanism of development of allergic shock

The occurrence of this pathology begins directly with the contact of the immune system with a certain allergen, as a result of which specific antibodies are produced, which in turn lead to the release of a huge number of inflammatory factors.

And these inflammatory factors further penetrate the tissues and organs, resulting in impaired circulation and blood clotting, which can lead to cardiac arrest.

Usually, anaphylactic shock develops upon repeated contact of the body with an irritant, although in some cases this pathology may also occur during the initial interaction with the allergen.

The first stage in the development of allergic shock is sensitization, that is hypersensitivity body to a particular allergen.

And already the second stage of this mechanism for the development of anaphylaxis is the anaphylactic reaction itself, which consists in a protective reaction of the immune system to the re-penetration of the allergen into the body.

The development of anaphylaxis is directly related to the reduced immunity of the body.

After the secondary entry of the irritant into the blood, specific substances are released, especially histamine, which is responsible for allergic reactions.

Such protective reactions of the body lead to the development of edema, vasodilation, which in turn provokes respiratory failure.

Allergic shock leads to the release of a huge amount of histamine, which disrupts the work of all systems and organs of the human body.

That is, we can say that the development of anaphylactic shock occurs in 3 successive stages:

• immunological stage;
• pathochemical stage;
• pathophysiological stage.

Primary symptoms with the rapid development of anaphylactic shock appear from the first seconds of penetration into the blood of the allergen. This lightning-fast development of symptoms especially occurs after the administration of the drug intravenously.

Signs of anaphylactic shock can occur from a couple of seconds to 40 minutes. Quite often, anaphylaxis passes in 2 phases, when after intensive treatment of the first attack, after 2-3 days, the second wave of symptoms of allergic shock occurs.

When anaphylaxis develops very quickly, most people experience the following symptoms:

• a sharp drop in blood pressure to a critical point;
• loss of consciousness, fainting;
• blanching, and sometimes blueing of the skin;
• the patient has sticky cold sweating;
• palpitations, weak pulsation;
• disturbed breathing process, convulsions, foam near the mouth;
• spontaneous defecation.

Symptoms of anaphylactic shock can be observed from the first seconds of the body's interaction with the allergen.

In the acute form of the development of anaphylactic shock, the following symptoms are observed:

• allergic manifestation in the form of a skin rash, redness of some parts of the body,;
• there is swelling of the lips, ears and eyelids;
• disturbed respiratory process, shortness of breath, voice change;
• dry paroxysmal cough;
• painful sensations of various kinds. They depend on the age of the patient. So, in children, anaphylaxis is expressed in abdominal cramps, and in adults - in a severe throbbing headache;
• the general condition of the patient worsens, which consists in a depressed mood, anxiety and fear of death;
• then there are lightning-fast signs of shock.

The subacute form of allergic shock is characterized by the same symptoms as other forms of pathology development, only their manifestation is much slower, so the sick person has time to seek medical help on his own.

In addition to the above signs, during an attack of anaphylaxis, some more symptoms may be observed:

• sensation of heat all over the body;
• sharp pain in the chest;
• nausea, vomiting;
• ear congestion;
• severe itching of reddened skin;
• dilated pupils;
• increased tactile sensitivity;
• blue fingers;
• loss of taste.

It is important to follow the algorithm of actions in the event of an attack, because in such a situation every second is important

First aid for anaphylaxis

With the onset of anaphylactic shock, especially lightning-fast, it is necessary to provide emergency medical care to the victim as soon as possible.

And the most important thing in this business is not to waste a single minute, otherwise the lost time, even the smallest one, will lead to death. Therefore, it is very important to be able to provide first aid to the victim of anaphylactic shock.

The algorithm of actions for anaphylaxis is quite simple and contains the following steps:

• if the stimulus that caused given state, identified, it is necessary to immediately exclude the contact of the patient with the allergen;
• the patient must be carefully placed in a horizontal position, on his back with raised legs;
• you need to constantly check the pressure and if it has dropped or risen sharply, then you need to take action and give a suitable medicine;
• the victim must be provided with an unhindered supply of fresh air. To do this, you need to unfasten and loosen the pressure of clothing on the body;
• it is necessary to calm the patient, since excitement will only intensify the pathological process;
• then you need to ensure the patency of the airways. To do this, slightly raise the head of the victim and slightly turn it to the side. If vomiting has begun, then you need to put the person on his side so that the vomit flows out;
• ask the victim if he has any allergy medication with him. And if possible, give the patient medicine;
• if anaphylaxis occurred as a result of an insect or animal bite, then ice or something cold should be applied to the affected area, and also drag this place with a tourniquet;
• call ambulance, although it would be better to do this at the very beginning.

• leave the victim alone;
• give the patient water or food;
• put something under the head;
• if anaphylaxis occurred due to intravenous administration of the drug, then the drug should be stopped from entering the body, and in no case should the needle be removed.

Diagnosis of allergic shock

After the first attack of anaphylactic shock has occurred, it is necessary to identify the substance that provoked this attack as soon as possible. It is good if the allergen is already known, but if the patient has not previously encountered allergic reactions, then the irritant can be determined using special studies.

To this end, the doctor prescribes the following measures:

• skin tests;
• blood and urine analysis;
• provocative tests;
• allergic history.

All studies are carried out as carefully as possible so that there is no sharp response of the body to the provocation of an allergic reaction.

Most safe way to determine an anaphylactic allergen is an allergen sorbent test. Safety this method diagnostics lies in the fact that the study is carried out outside the patient's body.

Hospitalization for allergic shock is simply necessary

Treatment of anaphylactic shock

After identifying the allergen that provoked an attack of anaphylaxis, it is prescribed complex treatment which is held in stationary conditions.

The main principles of treatment of allergic shock include:

• normalization of the work of all vital systems and organs;
• prevention of a sharp drop in blood pressure;
• prevention of coma development;
• prevention and removal of existing swelling of organs;
• removal of allergenic substances from the patient's blood.

If necessary, symptomatic treatment is carried out. For example, if a patient has vomit in the airways, then they are pumped out.

In most cases, the following medications are prescribed:

• antihistamines are used during outbreaks of an allergic reaction;
• intramuscular injection of adrenaline;
• glucocorticoids;
• drugs that relieve bronchospasm and clear the airways;
• drugs that activate cardiac activity;
• medicines that normalize blood pressure;
• infusion of fluids to prevent coma.

Treatment of anaphylaxis begins with the identification of the allergen that triggered the attack.

And for the prevention of anaphylactic shock, you need to avoid contact with allergenic substances, always have a mini-first aid kit with the necessary medicines, undergo tests for the presence of allergic reactions to drugs, and purchase medicines in tablets, not ampoules.

And most importantly, do not allow a second attack of anaphylactic shock, otherwise the next time the symptoms will be more pronounced, and the consequences will be much more serious.

And if you've never had anaphylaxis, but you do have an allergy, anaphylactic shock is a possible condition that can occur at any time, so you need to treat your existing allergy as soon as it occurs. Taking all the necessary medications for allergies, the risk of anaphylaxis will be minimal.

What is anaphylactic shock, how it can be recognized and what should be done if anaphylaxis occurs, everyone should know.

Since the development of this disease often occurs in a fraction of a second, the prognosis for the patient depends primarily on the competent actions of nearby people.

What is anaphylaxis?

Anaphylactic shock, or anaphylaxis, is an acute condition that occurs as an immediate type of allergic reaction, which occurs when the body is repeatedly exposed to an allergen (foreign substance).

It can develop in just a few minutes, is a life-threatening condition and is a medical emergency.

Mortality is about 10% of all cases and depends on the severity of anaphylaxis and the rate of its development. The frequency of occurrence annually is approximately 5-7 cases per 100,000 people.

Basically, this pathology affects children and young people, since most often it is at this age that a repeated meeting with the allergen occurs.

Causes of anaphylactic shock

The causes that cause the development of anaphylaxis can be divided into main groups:

• medications. Of these, anaphylaxis is most often provoked by the use of antibiotics, in particular penicillin. Also, unsafe drugs in this regard include aspirin, some muscle relaxants and local anesthetics;
• insect bites. Anaphylactic shock often develops when bitten by hymenoptera (bees and wasps), especially if they are numerous;
• food products. These include nuts, honey, fish, some seafood. Anaphylaxis in children can develop with the use of cow's milk, products containing soy protein, eggs;
• vaccines. An anaphylactic reaction during vaccination is rare and may occur on certain components in the composition;
• contact with latex products.

Risk Factors for Anaphylaxis

The main risk factors for the development of anaphylactic shock include:

• the presence of an episode of anaphylaxis in the past;
• weighted history. If the patient suffers, or, then the risk of developing anaphylaxis increases significantly. The severity of the course of the disease increases, and therefore the treatment of anaphylactic shock is a serious task;
• heredity.

Clinical manifestations of anaphylactic shock

Symptoms of anaphylactic shock

The time of onset of symptoms directly depends on the method of introduction of the allergen (inhalation, intravenous, oral, contact, etc.) and individual characteristics.

So, when an allergen is inhaled or consumed with food, the first signs of anaphylactic shock begin to be felt from 3-5 minutes to several hours, with intravenous ingestion of the allergen, the development of symptoms occurs almost instantly.

Initial symptoms state of shock usually manifested by anxiety, dizziness due to hypotension, headache, unreasonable fear. In their further development, several groups of manifestations can be distinguished:

• skin manifestations(see photo above): fever with characteristic reddening of the face, itching on the body, rashes like urticaria; local edema. These are the most common signs of anaphylactic shock, however, with the immediate development of symptoms, they may occur later than the rest;
• respiratory: nasal congestion due to swelling of the mucosa, hoarseness and difficulty in breathing due to laryngeal edema, wheezing, coughing;
• cardio-vascular: hypotensive syndrome, increased heart rate, pain in the chest;
• gastrointestinal: difficulty in swallowing, nausea, turning into vomiting, spasms in the intestines;
• manifestations of CNS damage are expressed from initial changes in the form of lethargy to total loss consciousness and the emergence of convulsive readiness.

Stages of development of anaphylaxis and its pathogenesis

In the development of anaphylaxis, successive stages are distinguished:

1. immune (introduction of the antigen into the body, further formation of antibodies and their absorption "settlement" on the surface of mast cells);
2. pathochemical (reaction of newly arrived allergens with already formed antibodies, release of histamine and heparin (inflammatory mediators) from mast cells);
3. pathophysiological (stage of manifestation of symptoms).

The pathogenesis of the development of anaphylaxis underlies the interaction of the allergen with immune cells organism, the consequence of which is the release of specific antibodies.

Under the influence of these antibodies, there is a powerful release of inflammatory factors (histamine, heparin), which penetrate into the internal organs, causing their functional failure.

The main variants of the course of anaphylactic shock

Depending on how quickly the symptoms develop and how quickly first aid is provided, one can assume the outcome of the disease.

The main types of anaphylaxis are:

• malignant - characterized by the instant after the introduction of the allergen, the appearance of symptoms with access to organ failure. The outcome in 9 cases out of 10 is unfavorable;
• protracted - noted during application medicines slowly excreted from the body. Requires constant administration of drugs by titration;
• abortive - such a course of anaphylactic shock is the easiest. Under the influence of drugs quickly stops;
• recurrent - the main difference is the repetition of episodes of anaphylaxis due to the constant allergization of the body.

Forms of development of anaphylaxis depending on the prevailing symptoms

Depending on which symptoms of anaphylactic shock prevail, several forms of the disease are distinguished:

• Typical. The first signs are skin manifestations, especially itching, swelling at the site of exposure to the allergen. Violation of well-being and the appearance of headaches, causeless weakness, dizziness. The patient may experience intense anxiety and fear of death.
• Hemodynamic. Significant without medical intervention leads to vascular collapse and cardiac arrest.
• Respiratory. Occurs when the allergen is directly inhaled with air flow. Manifestations begin with nasal congestion, hoarseness, then there are violations of inhalation and exhalation due to swelling of the larynx (this is the main cause of death in anaphylaxis).
• CNS lesions. The main symptomatology is associated with dysfunction of the central nervous system, as a result of which there is a violation of consciousness, and in severe cases, generalized convulsions.

Severity of anaphylactic shock

To determine the severity of anaphylaxis, three main indicators are used: consciousness, blood pressure level, and the rate of effect of the treatment started.

According to severity, anaphylaxis is classified into 4 degrees:

1. First degree. The patient is conscious, restless, there is a fear of death. BP is reduced by 30-40 mm Hg. from the usual (normal - 120/80 mm Hg). The ongoing therapy has a quick positive effect.
2. Second degree. The state of stupor, the patient is difficult and slow to answer the questions asked, there may be a loss of consciousness, not accompanied by respiratory depression. BP below 90/60 mm Hg. The effect of the treatment is good.
3. Third degree. Consciousness is often absent. Diastolic blood pressure is not determined, systolic is below 60 mm Hg. The effect of the therapy is slow.
4. fourth degree. Unconscious, blood pressure is not determined, there is no effect from the treatment, or it is very slow.

Anaphylaxis Diagnosis Options

Diagnosis of anaphylaxis should be carried out as quickly as possible, since the prognosis of the outcome of the pathology mainly depends on how quickly first aid was provided.

In making a diagnosis, the most important indicator is a detailed history taking together with clinical manifestations diseases.

However, some laboratory research methods are also used as additional criteria:

• General blood analysis. The main indicator of the allergic component is (the norm is up to 5%). Along with this, anemia (a decrease in hemoglobin levels) and an increase in the number of leukocytes may be present.
• Blood chemistry. There is an excess normal values liver enzymes (ALAT , ASAT, alkaline phosphatase), kidney tests.
• Plain radiography of the chest. Often, the picture shows interstitial pulmonary edema.
• ELISA. It is necessary for the detection of specific immunoglobulins, in particular Ig G and Ig E. Their increased level is characteristic of an allergic reaction.
• Determination of the level of histamine in the blood. It must be done shortly after the onset of symptoms, as histamine levels drop sharply over time.

If the allergen could not be detected, then after the final recovery, the patient is recommended to consult an allergist and perform allergy tests, since the risk of recurrence of anaphylaxis is sharply increased and prevention of anaphylactic shock is necessary.

Differential diagnosis of anaphylactic shock

Difficulties in making a diagnosis of anaphylaxis almost never arise due to bright clinical picture. However, there are situations where it is necessary differential diagnosis.

Most often, these pathologies give similar symptoms:

• anaphylactoid reactions. The only difference will be the fact that anaphylactic shock does not develop after the first encounter with the allergen. The clinical course of pathologies is very similar and differential diagnosis cannot be carried out only on it, a thorough analysis of the anamnesis is necessary;
• vegetative-vascular reactions. They are also characterized by a decrease in blood pressure. Unlike anaphylaxis, it does not manifest itself as bronchospasm, or itching;
• collaptoid conditions caused by taking ganglioblockers or other drugs that reduce pressure;
• - the initial manifestations of this disease can also be manifested hypotensive syndrome, however, specific manifestations of the allergic component (itching, bronchospasm, etc.) are not observed with it;
• carcinoid syndrome.

Providing emergency care for anaphylaxis

Emergency care for anaphylactic shock should be based on three principles: the fastest possible delivery, impact on all links of pathogenesis, and continuous monitoring of the activity of the cardiovascular, respiratory and central nervous systems.

Main directions:

• cupping;
• therapy aimed at relieving the symptoms of bronchospasm;
• prevention of complications from the gastrointestinal and excretory systems.

First aid for anaphylactic shock:

1. Try to identify the possible allergen as quickly as possible and prevent its further exposure. If an insect bite was noticed, apply a tight gauze bandage 5-7 cm above the bite site. With the development of anaphylaxis during the introduction medicinal product it is necessary to urgently complete the procedure. If intravenous administration was carried out, then the needle or catheter should not be removed from the vein. This allows subsequent therapy by venous access and reduces the duration of drug exposure.
2. Move the patient to a hard, level surface. Raise your legs above head level;
3. Turn the head to the side to avoid asphyxia with vomit. Be sure to release oral cavity from foreign objects (for example, dentures);
4. Provide access to oxygen. To do this, unfasten the squeezing clothing on the patient, open the doors and windows as much as possible to create a flow of fresh air.
5. If the victim loses consciousness, determine the presence of a pulse and free breathing. In their absence, immediately begin artificial ventilation of the lungs with chest compressions.

Algorithm for providing medical assistance:

First of all, all patients are monitored for hemodynamic parameters, as well as respiratory function. The application of oxygen is added by supplying through a mask at a rate of 5-8 liters per minute.

Anaphylactic shock can lead to respiratory arrest. In this case, intubation is used, and if this is not possible due to laryngospasm (swelling of the larynx), then tracheostomy. Drugs used for drug therapy:

• Adrenalin. The main drug for stopping an attack:
  • Adrenaline is applied 0.1% at a dose of 0.01 ml / kg (maximum 0.3-0.5 ml), intramuscularly in the anterior outer part of the thigh every 5 minutes under the control of blood pressure three times. If therapy is ineffective, the drug can be re-administered, but overdose and the development of adverse reactions should be avoided.
  • with the progression of anaphylaxis - 0.1 ml of a 0.1% solution of adrenaline is dissolved in 9 ml of saline and administered at a dose of 0.1-0.3 ml intravenously slowly. Re-introduction according to indications.
• Glucocorticosteroids. Of this group of drugs, prednisolone, methylprednisolone, or dexamethasone are most commonly used.
  • Prednisolone at a dose of 150 mg (five ampoules of 30 mg each);
  • Methylprednisolone at a dose of 500 mg (one large ampoule of 500 mg);
  • Dexamethasone at a dose of 20 mg (five 4 mg ampoules).

Smaller doses of glucocorticosteroids are ineffective in anaphylaxis.

• Antihistamines. The main condition for their use is the absence of hypotensive and allergenic effects. Most often, 1-2 ml of a 1% diphenhydramine solution is used, or ranitidine at a dose of 1 mg / kg, diluted in a 5% glucose solution to 20 ml. Administer intravenously every five minutes.
• Eufillin used with the ineffectiveness of bronchodilator drugs at a dosage of 5 mg per kilogram of body weight every half hour;
• With bronchospasm, not stopped by adrenaline, the patient is nebulized with a solution of berodual.
• dopamine. Used for hypotension refractory to adrenaline and infusion therapy. It is used at a dose of 400 mg diluted in 500 ml of 5% glucose. Initially, it is administered until the systolic pressure rises within 90 mm Hg, after which it is transferred to the introduction by titration.

Anaphylaxis in children is stopped by the same scheme as in adults, the only difference is the calculation of the dose of the drug. Treatment of anaphylactic shock is advisable to carry out only in stationary conditions, because. within 72 hours development of repeated reaction is possible.

Prevention of anaphylactic shock

Prevention of anaphylactic shock is based on avoiding contact with potential allergens, as well as substances to which an allergic reaction has already been established by laboratory methods.

For any type of allergy in a patient, the appointment of new drugs should be minimized. If there is such a need, then a preliminary skin test is mandatory to confirm the safety of the appointment.