Anaphylactic shock is a sharp pathological state which arises at repeated penetration of allergen therefore heavy haemo dynamic violations and a hypoxia develop. Are the main reasons for development of an anaphylaxis receipt in an organism of various medicines and vaccines, stings of insects, food allergy. At heavy degree of shock quickly there occurs consciousness loss, the coma and in the absence of emergency aid – a lethal outcome develops. Treatment consists in the termination of receipt in an allergen organism, restoration of function of blood circulation and breath, if necessary – holding resuscitation actions.
Anaphylactic shock (anaphylaxis) is the heavy system allergic reaction of immediate type developing at contact with alien substances anti-genes (medicamentous means, serums, X-ray contrast agents, foodstuff, at stings of snakes and insects) which is followed by the expressed violations of blood circulation and functions of bodies and systems.
Anaphylactic shock develops approximately at one of 50 thousand people, and the quantity of cases of this system allergic reaction grows every year. So, in the United States of America more than 80 thousand cases of development of anaphylactic reactions are registered every year, and the risk of emergence at least of one episode of an anaphylaxis during life exists at 20-40 million residents of the USA. On statistical data, approximately in 20% of cases use of medicines is the reason of development of anaphylactic shock. Quite often the anaphylaxis comes to an end with a lethal outcome.
Reasons of anaphylactic shock
Any substance getting into a human body can become the allergen leading to development of anaphylactic reaction. Introduction of various medicamentous means is the most frequent reason of anaphylactic shock. These are antibacterial (antibiotics and sulfanylamides), hormonal means (insulin, adrenokortikotropny hormone, and progesterone), fermental medicines, anesthetics, heterological serums and vaccines. Hyper reaction of immune system can develop also on introduction of the X-ray contrast agents used when carrying out tool researches.
One more causal factor of emergence of anaphylactic shock – stings of snakes and insects (bees, bumblebees, hornets, ants). In 20-40% of cases of an uzhaleniye of bees beekeepers become victims of an anaphylaxis.
The anaphylaxis quite often develops on food allergens (eggs, dairy products, fish and seafood, soy and a peanut, nutritional supplements, dyes and fragrances, and also the biological products used for processing of fruits of vegetables and fruit). So, more than 90% of cases of heavy anaphylactic reactions develop in the USA on hazelnuts. In recent years the quantity of cases of development of anaphylactic shock on sulfites – the nutritional supplements used for longer safety of a product became frequent. These substances add to beer and wine, fresh vegetables, fruit, sauces.
Anaphylaxis cases on products from latex become frequent (rubber gloves, catheters, tire production, etc.), and the cross allergy to latex and some fruit (avocado, bananas, a kiwi) is quite often observed.
The disease can develop at influence of various physical factors (the work connected with muscular tension, sports trainings, cold and heat), and also at a combination of reception of some foodstuff (more often it is shrimps, nuts, chicken meat, a celery, white loaf) and the subsequent physical activity (work on a personal plot, sports, run, swimming etc.). Anaphylactic reactions develop with hereditary predisposition more often (increase in reactivity of immune system – both cellular, and humoral is noted).
Anaphylactic shock represents immediate generalized allergic reaction which is caused by interaction of substance with anti-gene properties and IgE immunoglobulin. At repeated intake of allergen various mediators are released (a histamine, prostaglandins, hemotaksichesky factors, leykotriyena, etc.) and numerous system manifestations from cardiovascular, respiratory systems, digestive tract, integuments develop.
It is a collapse of vessels, a gipovolemiya, reduction of smooth muscles, a bronchospasm, slime hyper secretion, hypostases of various localization and other pathological changes. As a result the volume of the circulating blood decreases, arterial pressure decreases, the sosudodvigatelny center will be paralyzed, the shock volume of heart decreases and the phenomena of cardiovascular insufficiency develop. System allergic reaction at anaphylactic shock is followed also by development of respiratory insufficiency because of a spasm of bronchial tubes, a congestion in a gleam of bronchial tubes viscous mucous separated, emergence of hemorrhages and atelektaz in tissue of lungs, stagnation of blood in a small circle of blood circulation. Violations are noted also from integuments, abdominal organs and a small pelvis, endocrine system, a brain.
Symptoms of anaphylactic shock
Clinical symptoms of anaphylactic shock depend on specific features of an organism of the patient (sensitivity of immune system to concrete allergen, age, existence of associated diseases, etc.), a way of penetration of substance with anti-gene properties (parenterally, through airways or a digestive tract), the prevailing "shock body" (heart and vessels, airways, integuments). At the same time the characteristic symptomatology can develop as it is lightning (during parenteral introduction of a medicine), and in 2-4 hours after the meeting with allergen.
Sharply arising violations of work of cardiovascular system are characteristic of an anaphylaxis: a lowering of arterial pressure with the advent of dizziness, weaknesses, unconscious states, arrhythmia (tachycardia, premature ventricular contraction, vibrating arrhythmia etc.), development of a vascular collapse, myocardial infarction (pain behind a breast, fear of death, hypotension). Respiratory signs of anaphylactic shock is an emergence of the expressed short wind, rinore, a dysphonia, the whistling breath, a bronchospasm and asphyxia. Neuromental disorders are characterized by the expressed headache, psychomotor excitement, sensation of fear, alarms, a convulsive syndrome. There can be malfunction of pelvic bodies (an involuntary urination and defecation). Skin symptoms of an anaphylaxis – emergence of an eritema, a small tortoiseshell, an angiootek.
The clinical picture will differ depending on weight of an anaphylaxis. Mark out 4 severity:
At the I degree of shock of violation insignificant, the arterial pressure (AP) is reduced by 20-40 mm of mercury. Consciousness is not broken, dryness in a throat, cough, pains behind a breast, feeling of heat, the general concern disturbs, there can be rash on skin.
More expressed violations are characteristic of the II degree of anaphylactic shock. At the same time systolic HELL falls till 60-80, and diastolic – to 40 mm of a mercury column. Sensation of fear, the general weakness, dizziness, the phenomena of a rinokonjyunktivit, a rash on skin with an itch disturbs, Quincke, difficulties during the swallowing and a conversation, belly-ache and a waist, weight behind a breast, short wind at rest swelled. Quite often there is repeated vomiting, control of process of an urination and defecation is broken.
The III severity of shock is shown by decrease systolic HELL to 40-60 mm of mercury., and diastolic – to 0. There occurs consciousness loss, pupils extend, skin cold, sticky, pulse becomes threadlike, the convulsive syndrome develops.
The IV degree of an anaphylaxis develops immediately. At the same time the unconscious patient, HELL and pulse are not defined, there is no warm activity and breath. Urgent resuscitation actions are necessary for rescue of life of the patient.
At getting out of a state of shock at the patient weakness, slackness, block, fever, mialgiya, artralgiya, short wind, heartaches remains. Nausea, vomiting, pains on all stomach can be noted. After knocking over of sharp manifestations of anaphylactic shock (in the first 2-4 weeks) complications in the form of bronchial asthma and recurrent urticaria, allergic myocarditis, hepatitis, a glomerulonefrit, a system red volchanka, a nodular periarteriit and so forth quite often develop.
Diagnostics of anaphylactic shock
The diagnosis of anaphylactic shock is established mainly on clinical symptomatology as there is no time left for detailed collecting anamnestichesky data, carrying out laboratory analyses and allergologichesky tests. Only the accounting of circumstances during which there came the anaphylaxis – parenteral introduction of medicine, a sting of a snake, consumption of a certain product etc. can help.
During survey the general condition of the patient, function of the main bodies and systems is estimated (cardiovascular, respiratory, nervous and endocrine). Already visual survey of the patient with anaphylactic shock allows to define clarity of consciousness, existence of a pupillary reflex, depth and frequency of breath, a condition of integuments, preservation of control over function of an urination and defecation, existence or absence of vomiting, a convulsive syndrome. Further existence and qualitative characteristics of pulse on peripheral and main arteries, the level of arterial pressure, auskultativny data are defined when listening tones of heart and breath over lungs.
After rendering emergency aid to the patient with anaphylactic shock and elimination of direct threat for life is conducted the laboratory and tool researches allowing to specify the diagnosis and to exclude other diseases with similar symptomatology. When carrying out laboratory all-clinical inspection make clinical blood test (, increase in quantity of erythrocytes, neutrophils, eosinophils comes to light more often), expressiveness of respiratory and metabolic acidosis (pH, the partial pressure of carbon dioxide and oxygen is measured in blood) is estimated, the water and electrolytic balance, indicators of system of fibrillation, etc. is defined.
Allergologichesky inspection at anaphylactic shock provides definition of a triptaza and SILT-5, level of the general and specific immunoglobulin E, a histamine, and after knocking over of sharp displays of an anaphylaxis – identification of allergens by means of skin tests and a laboratory research.
On the electrocardiogram signs of an overload of the right departments of heart, myocardium ischemia, tachycardia, arrhythmia are defined. On the roentgenogram of bodies of a thorax symptoms of emphysema of lungs can come to light. Monitoring of arterial pressure, heart rate and breath, the ECG is carried out to the sharp period of anaphylactic shock and within 7-10 days. If necessary carrying out a pulsoksimetriya, kapnometriya and kapnografiya, determination of arterial and central venous pressure by an invasive method is appointed.
Differential diagnostics is carried out with other states which are followed by the expressed decrease HELL, violations of consciousness, breath and warm activity: with cardiogenic and septic shock, a myocardial infarction and sharp cardiovascular insufficiency of various genesis, a thrombembolia of a pulmonary artery, sinkopalny states and an epileptic syndrome, a hypoglycemia, sharp poisonings, etc. It is necessary to distinguish anaphylactic shock from anafilaktoidny reactions, similar on manifestations, which develop already at the first meeting with allergen and at which immune mechanisms are not involved (interaction an anti-gene antibody).
Sometimes differential diagnostics with other diseases is complicated, especially in situations when there are several causal factors which caused development of a state of shock (a combination of different types of shock and accession of an anaphylaxis to them in response to introduction of any medicine).
Treatment of anaphylactic shock
Medical actions at anaphylactic shock are directed to the fastest elimination of dysfunction of vitals and systems of an organism. First of all it is necessary to eliminate contact with allergen (to stop introduction of a vaccine, medicine or X-ray contrast substance, to remove a sting of a wasp, etc.), if necessary – to limit venous outflow by imposing of a plait of introduction of medicine or an uzhaleniye one extremity higher than the place an insect, and also to cut away this place solution of adrenaline and to put cold. It is necessary to restore passability of airways (introduction of an air duct, an urgent intubation of a trachea or tracheotomy), to provide giving in lungs of pure oxygen.
Introduction of simpatomimetik (adrenaline) hypodermically repeatedly with the subsequent intravenous drop administration before improvement of a state is carried out. At a severe form of anaphylactic shock the dopamine in individually picked up dose is intravenously entered. The scheme of emergency aid joins glucocorticoids (Prednisolonum, dexamethasone, a beta metazone), the infusional therapy allowing to fill the volume of the circulating blood, to eliminate haemo concentration and to restore the acceptable level of arterial pressure is carried out. Symptomatic treatment includes use of antihistamines, bronchial spasmolytics, diuretics (according to strict indications and after stabilization HELL).
Hospitalization of patients with anaphylactic shock is carried out within 7-10 days. Further observation is necessary for identification of possible complications (late allergic reactions, myocarditis, glomerulonefrit etc.) and their timely treatment. The forecast at anaphylactic shock depends on timeliness of holding adequate medical actions and the general condition of the patient, existence of associated diseases.