Anaphylactic shock

[Outlined]

Anaphylactic shock (anaphylaxis, anaphylactic shock) is outside of certain substances into the antigen has sensitized the body, through the immune mechanism in a short period of time in a strong involvement of multiple organ group. Anaphylactic shock performance and level of response by the body, antigen into the volume and channels and are very different. Are usually sudden and very dramatic, if not timely treatment, often life-threatening.

[Treatment]

Must act quickly, seize the opportunity to actively address. ① immediately stop and shift into the branch of suspicious allergens, pathogens or drugs. Ligation injection Chong Yao site or over the limb to slow the absorption can also be injected or sting to 0.005 percent of the local adrenaline 2 ~ 5 ml closed injection. ② immediately to 0.1 percent adrenaline, the first subcutaneous injection of 0.3 ~ 0.5 ml, then injected into a vein puncture 0.1 ~ 0.2 ml, followed by 5 percent drop glucose injection, to maintain smooth flow of intravenous injection. Adrenergic receptor β effect through the rapid relaxation of bronchial spasms, through α receptor effect on the peripheral vascular contraction. It can also confront some of the media allergic Ⅰ-release, so this is where the first choice of drug, in the course of the applications can be repeated several times. General after 1 or 2 times epinephrine injection, most of the patients symptoms of shock in a half-hour can be recovered. Conversely, if not shock sustained improvement is a serious case of early intravenous dexamethasone 10 ~ 20 mg, the acid test-hydride 200 ~ 400 mg. Has the discretion to choose a group of more lasting effect, the side effects of smaller anti-shock drugs such as norepinephrine, Ala Ming (between hydroxylamine). At the same time to vasoactive drugs, blood volume and promptly added, the first infusion of 500 ml can quickly infusion, adult general of the first day of rehydration up to 400 ml. ③ anti-allergic and symptomatic treatment, commonly used is 10 mg or chlorpheniramine promethazine 25 ~ 50 mg, intramuscular, sits flat, oxygen and maintain respiratory smooth.

As in allergic diseases shock when the patient's allergy threshold very low, some of the original may not allergic to the drug allergens. Therefore, the treatment of this medication must not excessive.

[ET]

As allergens cause the disease antigen substances are:

(A) of xenotransplantation (of) the secretion of protein (insulin, vasopressin), the enzyme (chymotrypsin, penicillin-), pollen extract (pig grass, trees, grass), food (egg white, milk, hard shell Fruits, dried seafood, chocolate), anti-serum (anti-serum or anti-lymphocyte IVIG), occupational exposure to the protein (rubber products), the bees toxin.

(B) polysaccharides such as iron dextran.

(C) many commonly used drugs such as antibiotics (penicillin, cephalosporins adriamycin, amphotericin B, nitro furans properly due to taste), local anesthetic (procaine, lidocaine), vitamins (thiamin, folic acid ), Diagnostic agents (iodized X-ray contrast agent, iodine bromide phthalate), the occupational exposure to chemical agents (ethylene oxide).

The vast majority of allergic shock is a typical type Ⅰ multi-organ allergic reaction in the body, especially the cycle of the performance. Outside the antigen of substances (antigens certain drugs is incomplete, but after entering the body with a combination of protein Chengquan antigen) enters the body can stimulate the immune system to produce antibodies, IgE production, due to physical varies widely. These specific IgE cells have a stronger pro-nature, with the skin, bronchial, the vessel walls, and so the "target cells" combination. When the same again after the antigen has been sensitized with the individual contacts, we can inspire much of the allergic type Ⅰ, the process of release of histamine and platelet activating factor, such as edema is caused by multiple organ, such as clinical exudation The direct cause of performance.

In blood, plasma or immunoglobulin in the process of occasionally can be seen rapid onset of anaphylactic shock, they are the cause of three: ① donors with the specific IgE who are receiving treatment by drugs (such as penicillin G) from the reaction . ② selective IgA to the lack of multiple infusion of IgA blood products, can produce the anti-IgA IgG antibody category. When the re-injection of IgA products, it is possible IgA-anti-IgA antibody immune complex, a type Ⅲ allergy caused by anaphylactic shock. ③ for intravenous infusion of gamma globulin (C-) formulations contain high molecular weight of the C-polymer, can activate complement, a C3a, C4a, C5a, and other allergic toxin; then the activation of mast cells produce anaphylactic shock. A small number of patients in the use of drugs such as opium tincture, dextran, a high degree of ionizing X-ray contrast agent or antibiotics (such as polymyxin B), mainly through to the mast cell degranulation, also have allergic shock of clinical manifestations. In recent years, people would not exist allergens and the antibody response, that is through non-immune mechanisms of allergic symptoms and signs called shock-like allergic reaction (anaphylactoid reaction).

[Pathological changes:

Because of this disease and the main features of sudden death: acute pulmonary bleeding and excessive inflation, throat swelling, visceral congestion, pulmonary edema and bleeding. Endoscopic airway submucosal foreseeable edema extremely small airway secretions increase, bronchial and lung stromal vascular congestion associated with eosinophil infiltration, about 80 percent of deaths and myocardial necrosis, or the focal lesions. Spleen, liver and mesenteric vascular also more associated with congestive eosinophil infiltration. There are also a few cases, such as gastrointestinal bleeding.

[Clinical]

Most of Curan of the disease occurred in about half of patients receive cause antigen (such as the injection of penicillin G, etc.) within five minutes symptoms, only 10% of patients with symptoms starting in half an hour later, a very small number of patients in the continuous treatment in the process of this disease .

Anaphylactic shock has two main characteristics: First performance of a shock that the rapid blood pressure dropped to 10.6/6.6 kPa (80/50mmHg) below, a consciousness disorder patients, ranging from dim, then re-coma. The second is in shock before or at the same time, often some of the symptoms associated with allergies. Are as follows.

(A) skin mucosa performance anaphylactic shock is often the earliest and most often the symptoms, including skin Chaohong, itching, followed by extensive and urticaria (or) vessels and nerves of edema; can appear sneeze, water samples nose, Music Dumb, and even affect breathing.

(B) symptoms of obstructive airway disease is the most common performance, but also the main cause of death. As airway edema, secretions increase, coupled with jets and (or) bronchial spasms, plug flu patients throat, chest tightness, short breath, wheezing, Bieqi, cyanosis, resulting from suffocation and death.

(C) performance of circulatory failure patients to have palpitations, sweating, looking pale and weak pulse rate and then developed into Zhileng, cyanosis, the rapid decline in blood pressure, pulse disappeared, and even less than measuring blood pressure, leading to cardiac arrest. A small number of patients with existing coronary atherosclerosis may be complicated by myocardial infarction.

(D) awareness of the changes are often first appear fear, irritability and dizziness; with cerebral edema and cerebral hypoxia intensified, in unclear or complete loss of consciousness; can also issued five-stroke type convulsions, limb rigidity, and so on.

(5) Other more common symptoms are irritating cough, for a Ti, nausea, vomiting, abdominal pain, diarrhea, incontinence can occur final.

[Diagnosis]

Benbingfasheng soon, it is necessary to make timely diagnosis. Where in the (especially after injection) antigen of the substance or a drug, or bees bites occur immediately after the general reaction, drugs and difficult to explain their pharmacological effects, they should immediately be taken into account the possibility of this disease, it was General little difficult diagnosis. However, it should be except for the following circumstances.

(A) vagus vascular syncope (or vagus vascular collapse, vasovagal collapse) occurred after the injection, in particular, the patients have fever, low blood sugar or the tendency of water loss when. Patients Changcheng looking pale, nausea, a cold sweat, could then syncope, it is easily misdiagnosed as anaphylactic shock. However, this disease no itching or rashes, syncope sits flat immediately after the turn for the better, although low blood pressure but slow pulse, and these different anaphylactic shock. Vagal syncope vascular Atropine can be used in the treatment.

(B) edema hereditary vascular disease (hereditary angioedema) This is a regular chromosomes from the lack of genetic complement C1 esterase inhibitor of the disease. In some patients may be non-specific factors (such as infection, trauma, etc.) stimulated a sudden onset, for the performance of the skin and mucous membrane of respiratory vascular edema. As the airway obstruction, patients also often wheezing, short breath and extreme difficulty in breathing, and anaphylactic shock is quite similar. However, the onset of slower, and many patients have family history or history of seizures since childhood, when the disease is usually no blood pressure dropped and no urticaria, which can be differentiated from anaphylactic shock.

Anaphylactic shock of the diagnosis of this specific disease prevention is of great significance, but the test should be conducted allergens ① in shock after lifting; ② in grams and Kangguominyao out of antibodies after; ③ such as a skin test, the best necessary Anti-shock drug. A small number of patients with negative skin test is still the possibility of occurrence of this disease.

[Prevention]

The most fundamental way to clear the cause of the allergens, and the lack of effective anti-avoidance. However, the clinical often difficult to make a specific diagnosis of allergens Furthermore, many patients are not immune from the mechanisms of allergic-like reaction. To this end should be noted: ① long before the allergy medication history, the positive patients should be eye-catching in the history of Home and detailed records. ② minimize do not have to use radio, the widespread use of oral agents. ③ of allergic patients in physical observation of injecting drug use after 15 to 20 minutes, must accept that this disease may be induced by drugs (such as methyl contrast agent), Yixian use of antihistamines or prednisone 20 ~ 30 mg. ④ skin test for the first pick of skin prick test as far as possible without a positive drug, as required, can be tried "by-test" or "desensitization test." Its principles in the anti-histamine drugs under the protection of patients from the very small dose was gradually increased by the amount of drug-min, until the patients have tolerated far. In the process of desensitization, there must be close observation of medical staff, water and ready to adrenaline, oxygen, intubation and intravenous injection can be a corticosteroid and all other emergency rescue measures.

[Prognosis]

Normally receive after the antigen of the symptoms of the late, the better the prognosis. Certain height in case of allergy, "like lightning" anaphylactic shock, often poor prognosis. Coronary heart disease have occurred in the context of the present time because of the concentration of plasma and blood pressure drop, often associated with myocardial infarction easy. Nervous system symptoms are also easy to resume after the residue after the hypoxic brain complications.

Since the overwhelming majority of the intermediary for the specific IgE allergic. Each from the corresponding allergens caused by the increase in delivery of IgE production, that is, once again contact occurred when the possibility of more severe reactions. For this reason, patients should be warned never to accept a similar allergen, and taboo in the medical records of drug registration card Home.