Anaphylactic shock

Overview of Allergic shock (anaphylaxis. anaphylactic shock) is outside certain antigen substances enter the body allergens, through the immune mechanism in a short period of time in a very strong multi-organ involvement syndrome. Anaphylactic shock performance and, according to the host response, antigen into the volume and channels, etc., and are very different. Usually occurs suddenly very keen, if not handled in a timely manner, often life-threatening. As a cause of allergic reactions caused the disease antigen substances : (1) mutant (sexual) protein Hormone (insulin, vasopressin), the enzyme (chymotrypsin, penicillin enzyme), pollen extract (pig grass, trees and grass), food (egg white, milk, nut, dried seafood, chocolate), the antiserum (anti-lymphocyte serum or anti-lymphocyte IVIG), occupational exposure to the protein (rubber products), bees toxin. (2) polysaccharides such as iron dextran. (3) Many common drugs such as antibiotics (penicillin, cephalosporins, amphotericin B, nitro - furans taste for properly), Local anesthetics (procaine, lidocaine), vitamins (thiamine, folic acid), diagnostic agents (iodized X-ray contrast agent, iodine bromide phthalocyanine), occupational exposure to chemical agents (ethylene oxide). The majority of anaphylactic shock is a typical type I allergic multiple organ in the body, especially the circulatory system performance. Outside the antigen-substances (drugs is a failure of certain antigens, But the human body with a fully integrated protein antigen) to enter the body can stimulate the immune system to produce antibodies. which IgE production, the physical differences are substantial differences. These specific IgE a strong pro-cell nature, with the skin, bronchi, the vascular wall, "target cells" combine. After again when the same antigen has been sensitized with the individual contacts, we will be able to stimulate widespread type I allergic. its process of the release of histamine and platelet-activating factor is caused by multiple organ edema, exudative clinical performance of the direct reason. In transfusion, plasma or immunoglobulin in the process, and occasionally can be seen rapid onset of anaphylactic shock, Their causes are threefold : ?٠blood donor-specific IgE with the subject are receiving drug therapy (such as penicillin G) reaction. ?ڠselective IgA deficiency of IgA-time infusion of blood products, the production of anti-IgA IgG antibody. When injected again with IgA products, the possibility of IgA-anti-IgA antibody immune complexes, Type III occurrence of allergic anaphylactic shock. ?۠for intravenous infusion of gamma globulin (c) The preparation of polymers containing C ball polymer can activate complement, have Inc, C4a, C5a and other allergic toxins; then the activation of mast cells, produce anaphylactic shock. A few patients in the application of drugs such as opium tincture, dextran, high degree of ionization of X-ray contrast agents or antibiotics (polymyxin B), through to the main mast cell degranulation, would have happened anaphylactic shock of clinical manifestations. In recent years, people would not exist, allergens and antibody response. through non-immune mechanisms of anaphylactic shock symptoms and signs as allergy-like reaction (anaphylac toid reaction). Pathological changes due to the disease and sudden death of the main pathological features are : acute pulmonary bleeding and excessive aeration, laryngeal edema, congestive offal, pulmonary edema and hemorrhage. Microscope airway submucosal edema extremely small airway secretions, bronchus and pulmonary vascular mesenchymal with congestive eosinophil infiltration, About 80% died and the focal myocardial necrosis or lesions. Spleen, liver and mesenteric also more congestive with eosinophil infiltration. A few cases may have gastrointestinal bleeding. Clinical manifestations of the disease most of the sudden; About half of patients in etiology antigen (such as penicillin G injection, etc.) occur within five minutes symptoms, only 10% of patients with symptoms in half an hour, a very small number of patients for treatment in the course of the disease emerged. Anaphylactic shock has two major characteristics : One is the shock that the performance of blood pressure dropped dramatically to 10 .6/6.6kPa (80/50mmHg) below patients to sense obstacles, ranging from the cover, where he collapsed. Second, in the emergence of shock or, often associated with allergy symptoms. Summarized below. (1) Mucocutaneous performance is often anaphylactic shock earliest and the most common symptom, including skin flushing and itching. Following extensive urticaria and (or) Angioedema; there can sneeze water nose, hoarseness, and even affect breathing. (2) airway obstruction symptoms of the disease is the most common manifestations, as well as the main cause of his death. As airway edema, increased secretion, together with hoses and (or) bronchial spasm, the patient suffered from throat to plug the flu, dyspnea, wheezing, apnea, cyanosis, resulting in suffocation and death. (3) performance of circulatory failure patients first palpitation, sweating, paleness, rapid but weak pulse; Then, as cold extremities, cyanosis, rapid decline in blood pressure, pulse disappeared, and even could not be detected in blood pressure, leading to cardiac arrest. Minorities original coronary sclerosis patients with myocardial infarction can be. (4) changes in awareness often happens first fear, irritability and dizziness; Along with cerebral anoxia and brain edema intensified, can occur consciousness or completely lost; also made five strokes-twitch and limb stiffness. (5) Other more common symptoms of irritating cough, sneeze consecutive fight, nausea, vomiting, abdominal pain, diarrhea, Finally, there may be incontinent. Treatment must act quickly and seize the opportunity to actively addressed. ?٠immediately cease support to enter and shift suspicious allergens, pathogens or drugs. Ligation or injection site grave-sweepers should always more physically in order to reduce absorption, can be injected or bites to the local 0.005% 2-adrenergic 5ml closed injection. ?ڠimmediately to the 0.1% epinephrine, the first 0.3 - 0.5 ml subcutaneously. Immediately after venipuncture for injection 0.1-0.2ml, following a 5% glucose injection droplets, the Department of intravenous flow. Through beta-adrenergic receptor effect to enable rapid relaxation of bronchial spasm, Europium receptor effect to enable small peripheral vasoconstriction. It can also confront some type I allergic to the media release, where the disease is the preferred drugs, in the course of disease were to be repeated several times. After a general meeting of two-adrenaline injection, the majority of patients in shock symptoms within half an hour can be gradually restored. Conversely, if no sustained improvement in shock that it is serious cases, early intravenous dexamethasone 10-20mg, Hydrocortisone the succinate-200-400mg. Can be used at the discretion of a group of more lasting efficacy, side effects of smaller anti-shock drugs such as norepinephrine, Aramine (Aramine). Given vasoactive drugs, and timely in blood volume, first-dose infusion of 500 ml rapid infusion, Adult first day of rehydration was typically up to 400 ml. ?۠anti-allergic and symptomatic treatment is commonly used chlorpheniramine 10 mg or 25 ~ 50 mg promethazine, intramuscular, recumbent, oxygen, to keep the airway open. With an allergic shock disorder, the patient's allergic threshold is very low, so that the original could not allergic to the drug allergen. Therefore, treatment with medication to avoid the excessive and indiscriminate. Differential diagnosis of jaw section due soon, it is necessary to make timely diagnosis. Where in (especially after injection) antigenic material or some drugs, bee stings or immediately after systemic reaction, and drugs to their own interpretation of the pharmacological effects, should be immediately taken into account the possibility of this disease. Therefore, in general diagnosis little difficulty. But except for the following. (1) vascular vagal syncope (or vagal vascular collapse. vasovagal collapse) occur after injection, especially patients with fever, LOCA or hypoglycemia tend. Patients appearing paleness, nausea, cold sweat, then be syncope, can easily be misdiagnosed as anaphylactic shock. But the disease no itching or rash, fainting by recumbent immediately after turn for the better, but in spite of low blood pressure pulse slow, These different anaphylactic shock. Vagal syncope vascular available atropine drug treatment. (2) of hereditary angioedema disease (hereditary angioedema) This is from a regular The lack of genetic chromosome complement C1 esterase inhibitor diseases. Patients in some non-specific factors (such as infection, trauma, etc.) stimulation sudden onset, performance of the skin and respiratory mucosa angioedema. As airway obstruction, the patient often wheezing, short breath and extreme difficulty breathing, and anaphylactic shock quite similar. But slower onset of this disease, many patients have family history or history of seizures since childhood, the incidence of blood pressure is usually no decline, no urticaria. Accordingly with anaphylactic shock phase identification. Anaphylactic shock the specificity of the diagnosis of disease prevention is of great significance, Only for allergen detection should ?٠in shock after lifting; ?ڠout in grams and antibody-after antihistamine; ?۠If skin test for the best anti-shock of the necessary drugs. Minorities skin test negative patients with the disease still occurred possible. Prevention of the most fundamental solution to the clear cause of the disease allergens, and the lack of effective anti-avoid. But in clinical often difficult to make a specific diagnosis of allergens, Moreover, many patients do not belong to the immune mechanism of allergic-like reaction. Because of this, we should pay attention to : ?٠consultation before making drug allergy history, positive history of the patient should be the homepage for smart and detailed records. ?ڠminimize medication-not to maximize the use of oral agents. ?۠right Allergies patients IDUs observed 15 ~ 20 minutes. on the need to accept the disease may be induced by drugs (such as methyl contrast agent), prefers the use of prednisone or antihistamines-20-30mg. ?ܠfirst skin test for skin-prick test as there was no drugs, if used, trial can be "desensitized test" or "testing desensitization." Its principle is the antihistamine drugs under the protection of patients from the very small dose was gradually increased desensitization drug dosage, Until patients have tolerated so far. The desensitization process, must have close medical observation, and are ready to water adrenaline, oxygen, Tracheal intubation and can intravenous corticosteroids, and other emergency rescue measures. The prognosis is usually accepted antigen after symptoms of the disease later, the better the prognosis. Certain highly allergic happen "like lightning" anaphylactic shock, often poor prognosis. Have coronary heart disease occurred in the context of the arrangement because the plasma concentration and blood pressure drop, which often associated with myocardial infarction. Nervous system symptoms resumed after cerebral hypoxia easy residues of various complications. As with the majority of the specific IgE mediated allergy. Each from the corresponding allergen-induced IgE production increased delivery times, again contact violent reaction to a bigger possibility. Therefore, patients should be warned never to accept similar allergens and taboos drug card registered in the records homepage.