allergies

Anaphylactic shock

Generality

Anaphylactic shock is a severe clinical syndrome, which can occur when a person sensitized to an allergen comes into contact with it again.

If, for example, a person is allergic to bee venom, after the initial sensitization (first sting of his life), every time he comes into contact with the poison of the insect there will be a certain danger of suffering an anaphylactic shock. This risk depends on the individual conditions (degree and type of hypersensitivity), the path of inoculation (skin, gastrointestinal tract, airways or blood), the amount of allergen and the speed of administration.

Symptoms of anaphylactic shock

To learn more: Symptoms Anaphylaxis

Anaphylactic shock is a particularly severe allergic reaction, which occurs only in certain circumstances. Knowing how to recognize the symptoms promptly is therefore essential to stop the triggering of a cascade of hemodynamic events that can lead to the death of the patient.

The symptom picture associated with anaphylactic shock, complex and multiform, generally passes through a series of manifestations of increasing gravity:

sharp drop in blood pressure and tachycardia → early symptoms of anaphylactic shock: intense pallor, generalized urticaria (itching that usually begins with hands and feet), profuse sweating with cold skin, dizziness, generalized sense of severe malaise, anxiety, anxiety, hoarseness, lowering of voice, dysphonia, irritated cough;

→ angioedema of the upper airway → bronchospasm and major respiratory difficulties, tachypnea with shallow breathing (hypocapnia); enteric symptoms may appear (abdominal pain, nausea and vomiting) and a generalized skin reaction (redness and widespread itching) is appreciated;

→ cyanosis (bluish discoloration of the skin) and marked sensation of suffocation;

→ circulatory collapse, unconsciousness and convulsions → coma and death that occurs following asphyxia, severe hypoxia or cardiac arrest due to severe hypotension.

The appearance of the typical symptoms of anaphylactic shock follows the exposure to the allergen of a time varying from a few seconds to over an hour (average interval less than 10 minutes), undergoing in this sense the influence of various factors, such as the structure and the route of antigen introduction (oral, inhalation, intravenous ...). In rapid-onset forms, for example, anaphylactic shock appears abruptly, separated from the newly listed prodromes.

Since only a timely and adequate therapy can bring the vital parameters and the clinical picture back to normal, the prognosis is the more serious the shorter the time between exposure to the allergen and the appearance of the typical clinical picture of anaphylactic shock. Furthermore, it is known that the severity of the allergic reaction is inversely proportional to the time of onset, although in some cases severe symptoms may occur some hours later.

INCIDENCE OF ANAPHYLACTIC SHOCK: estimated at 30-50 cases per 100, 000 inhabitants per year, with a mortality rate of 0.0006% (in the United States it is estimated that one death per 1600 is due to an anaphylactic shock, while the population considered at risk is between 1 and 15 percent).