Anaphylactic shock in adults

Anaphylaxis is a severe, potentially life-threatening allergic reaction. It can happen within seconds or minutes of contact with something you are allergic to, such as peanuts or bee stings. Anaphylaxis is possible in three variants – urticaria, Quincke’s edema, or the most severe manifestation is shock.

When exposed to a dangerous allergen, the immune system releases a flood of chemicals that can cause shock—blood pressure suddenly drops and airways constrict, blocking breathing. Signs and symptoms include a fast, weak pulse, skin rash, nausea, and vomiting. Common triggers include certain foods, certain medications, insect venoms, and latex.

Anaphylaxis requires adrenaline injections and subsequent treatment in the emergency room. If not treated immediately, anaphylaxis can be fatal.

Among all possible immune reactions, anaphylactic shock is the most severe reaction. This is a potentially life-threatening condition caused by an allergic reaction. Many people use the terms anaphylaxis and anaphylactic shock to mean the same thing. However, anaphylactic shock is a complication of anaphylaxis that occurs when blood pressure, due to a sudden loss of muscle tone, drops very low and the blood circulates poorly through the body.

An allergy occurs when a person’s immune system overreacts to a harmless substance called an allergen. This reaction causes the body to release chemicals (histamine, bradykinin, cytokines) that cause irritation and other symptoms. Usually, allergic reactions are mild and symptoms such as rash, itching, or runny nose occur. When a person’s immune system overreacts to an allergen, it can release chemicals that affect multiple systems in the body. This can lead to anaphylaxis. In some people, anaphylaxis can include anaphylactic shock.

Facts about anaphylactic shock:

• like anaphylaxis, anaphylactic shock is a life-threatening emergency;
• people with a history of anaphylactic reactions (acute urticaria or sudden angioedema) are at risk of anaphylactic shock;
• people who have had anaphylactic reactions should always carry an epinephrine injector with them.

Causes of anaphylactic shock in adults

Anaphylactic reactions in adults develop only due to allergies after a preliminary stage of sensitization (the production of antibodies to the allergen). Normally, the body, upon encountering antigens, produces proteins in response that can attack dangerous invaders, including viruses and bacteria. This is necessary in order to destroy the disease as soon as possible. With allergies, the immune system reacts to substances that are not dangerous for the body, and the reactions are too sharp and active.

A person with an allergy produces immunoglobulin E (IgE) proteins (instead of the normal M or G immunoglobulins) in response to harmless substances. These substances cause white blood cells, called mast cells, to release certain chemicals, often histamine and its analogs, that cause an allergic reaction.

Some allergens are more likely than others to cause such a violent reaction in the body. These common allergens can be:

• poisons that enter the body with insect bites;
• products (or rather, dietary proteins), including peanuts, walnuts, shellfish and eggs;
• latex particles;
• medicines, including penicillin, anesthetics, and aspirin.

However, any substance to which a person is allergic can cause an anaphylactic reaction.

Although uncommon, some people develop anaphylaxis as a result of aerobic exercise, such as jogging, or even less intense physical activity, such as walking. Eating certain foods before exercise or exercising in hot, cold, or humid weather has also been associated with anaphylaxis in some people. Talk to your doctor about precautions to take while exercising.

If you don’t know what triggers an allergy attack, certain tests can help identify the allergen. In some cases, the cause of anaphylaxis is never determined (idiopathic anaphylaxis).

Risk Factors

There are not many known risk factors for anaphylaxis, but some influences that may increase your risk include:

• previous anaphylaxis – if you have had anaphylaxis once, the risk of this serious reaction is increased, subsequent reactions may be more serious than the first;
• allergies or asthma – people with any of these conditions are at increased risk of anaphylaxis;
• some other conditions – these include heart disease and an abnormal accumulation of a certain type of white blood cell (mastocytosis).

An anaphylactic reaction can be life-threatening – it can lead to suffocation or cardiac arrest.

Symptoms of anaphylactic shock in adults

Possible symptoms of anaphylactic shock include difficulty breathing or swelling of the throat. Most people develop symptoms of anaphylaxis within minutes of eating or being exposed to the allergen. Less often, symptoms appear after a few hours. The most common symptoms of an anaphylactic reaction include:

• irritation of the nose, mouth, skin, or stomach, such as rash, diarrhea, or nasal congestion;
• difficulty breathing or wheezing;
• low blood pressure, which can cause fainting, dizziness, or confusion;
• swelling of the mouth, tongue, or throat;
• swollen lips;
• feeling of choking or trouble swallowing.

Some people experience anaphylactic shock as well as anaphylaxis. If a person is in anaphylactic shock, they experience symptoms associated with low blood pressure and insufficient oxygen supply to the organs. A person in anaphylactic shock may also pass out, lose bowel or bladder control (passing stools and urine), or experience chest pain.

Anaphylactic shock reactions are similar to other forms of medical shock. In someone who experiences a severe allergic reaction while in a life-threatening situation, it may be impossible to distinguish anaphylaxis from other causes of shock. However, in most people, this condition is easy to detect due to recent exposure to the allergen.

Early signs of anaphylactic shock

The early symptoms of anaphylactic shock vary and may seem relatively mild at first. These may include hives, itching, or a feeling of fear. People with a history of severe allergic reactions often have the same symptoms with each reaction.

Early warning signs that a person may be in anaphylactic shock include:

• face and body turns blue or white;
• there is swelling of the lips or face;
• possible wheezing, choking, hacking cough;
• shortness of breath increases, breathing becomes difficult;
• urticaria, especially if in several areas.

Treatment of anaphylactic shock in adults

Seek emergency medical attention if you or someone close to you has a severe allergic reaction.

First aid

Don’t wait for the symptoms to go away on their own. If the person with the seizure has an epinephrine auto-injector, give it immediately. Even if the symptoms improve after the injection, it is still necessary to go to the emergency room to make sure that the symptoms do not return even if the person is no longer exposed to the allergen. This second reaction is called biphasic anaphylaxis.

Diagnostics

Call your doctor if you have had a severe allergy attack or signs and symptoms of anaphylaxis in the past. Diagnosis and long-term treatment of anaphylaxis is difficult, so you may need to see a doctor who specializes in allergies and immunology.

Modern treatments

The adrenaline injector is the primary treatment for people suffering from anaphylaxis. Also called EpiPen, these injectors contain a single dose of the hormone adrenaline. Adrenaline cancels the action of substances produced during an allergic reaction. It can also prevent shock or reverse the shock process if it has already begun. The EpiPen is usually injected directly into the thigh and is only available with a doctor’s prescription.

People should call XNUMX if they experience initial symptoms or suspect they may be having an anaphylactic reaction. Treating anaphylaxis at home is not safe. If a person delays treatment, it can be fatal. Treatment always begins with the administration of adrenaline.

In the case of severe anaphylactic shock, a person may need additional treatment. This may include the following treatments and medications:

• carrying out oxygen therapy;
• intubation with a tube connected to a ventilator to help with breathing
• a beta-agonist shot to reduce airway swelling;
• antihistamines to reduce the severity of an allergic reaction;
• vasopressors to constrict blood vessels and increase blood pressure if it becomes dangerously low;
• corticosteroids to help block allergic reactions and reduce swelling
• intravenous fluids for low blood pressure.

For people with a history of anaphylactic reactions, it is important to know which substances or allergens are causing the symptoms. A doctor will usually recommend an allergy test. This is because people with a history of anaphylactic reactions to one substance may also have severe allergic reactions to other allergens. Avoiding these allergens can save lives.

People who are allergic to substances that cannot be avoided, such as insect bites, can prevent anaphylaxis by using injectable allergy medications.

Desensitization, also known as immunotherapy or allergy shots, involves slow and steady exposure to a small amount of an allergen to reduce the risk of an allergic reaction. People may ask for a referral to an allergist, who will decide if desensitization is an option.

Prevention of anaphylactic shock in adults at home

The best way to prevent anaphylaxis is to avoid substances that cause this severe reaction. Also:

• Make a medical alert tag or bracelet to indicate that you are allergic to certain medications or other substances.
• always keep a first aid kit with prescribed medicines on hand – your doctor can advise you on its specific contents, if you have an adrenaline autoinjector, check the expiration date and be sure to refill the prescription before it expires;
• be sure to tell all your doctors about reactions to medications you have had;
• if you are allergic to stinging insects, be careful with them – wear long-sleeved shirts and trousers; do not walk barefoot on the grass; avoid bright colors; do not use perfumes, colognes or scented lotions; do not drink soda from open cans outdoors; remain calm when near a stinging insect; back away slowly and avoid being hit by the insect;
• if you have a food allergy, carefully read the labels of all the foods you buy and eat – manufacturing processes can change, so it’s important to periodically check the labels on the foods you usually eat; when eating out, ask how each dish is prepared and find out what ingredients it contains, as even a small amount of food you are allergic to can cause a serious reaction.

Even if you’re careful, at some point you’re likely to come across what you’re allergic to. Fortunately, you can quickly and effectively respond to an emergency allergic reaction by knowing the signs and symptoms of an anaphylactic reaction and having a plan to quickly treat those symptoms.

Popular questions and answers

We asked questions regarding the development of anaphylaxis and the possible consequences Pathologist, Junior Researcher, National Research Center for Pediatric Hematology, Oncology and Immunology named after N.N. Dmitry Rogachev to Dmitry Abramov.