1 / 40

ANAPHYLAXIS - PowerPoint PPT Presentation

  • Uploaded on

ANAPHYLAXIS. Anaphylaxis Objectives. Upon completion the student will be able to: Define anaphylaxis Define antigen List ways an antigen can be introduced into the body Define antibody Describe the pathophysiology of allergic reactions and anaphylaxis. Anaphylaxis Objectives.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'ANAPHYLAXIS' - demitrius

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Anaphylaxis objectives

Upon completion the student will be able to:

  • Define anaphylaxis

  • Define antigen

  • List ways an antigen can be introduced into the body

  • Define antibody

  • Describe the pathophysiology of allergic reactions and anaphylaxis

Anaphylaxis objectives1

  • Discuss the effects of allergic reactions and anaphylaxis on the following body systems:

  • Skin

  • Respiratory

  • Cardiovascular

  • Gastrointestinal

  • Nervous

  • Describe the clinical presentation of the patient suffering an allergic reaction and anaphylaxis

Anaphylaxis objectives2

  • Discuss the assessment of the patient suffering an allergic reaction and anaphylaxis

  • Describe the management of a patient with a severe allergic reaction

  • Describe the actions of the following medications, and relate their usage in the management of allergic reactions and anaphylaxis:

  • Oxygen

  • Epinephrine

  • Antihistamines

  • Corticosteroids

  • Beta Agonists


  • An acute, generalized, and violent antigen-antibody reaction - the most severe from of an allergic reaction - that may be rapidly fatal even with prompt and appropriate emergency medical care.

  • Develops in seconds to minutes after ingestion, injection, inhalation or absorption of an antigenic substance.

Immune system
Immune System

  • Plays a central role in allergies and anaphylaxis.

  • Components of the immune system can be found in the blood, the bone narrow, the connective tissues, and in the lymphatic system.

Immune system1
Immune System

  • The immune response is a series of complex events with the goal being the destruction or inactivation of pathogens, abnormal cells, or foreign molecules such as toxins.

  • This can be accomplished through two mechanisms:

    1. Cellular Immunity

    2. Humoral Immunity

Cellular immunity
Cellular Immunity

  • Derived from special leukocytes called t lymphocytes.

  • Originate in the thymus and are primarily responsible for fighting infections of biological agents living certain body cells, including tuberculosis, many viral infections, and most fungal infections.

  • Involves the movement of WBC to attack and eliminate.

Humoral immunity
Humoral Immunity

  • More complicated.

  • Derived from B lymphocytes and results in the formation of antibodies. There are five classes of human antibodies (immunoglobulins)

  • They include:

    1. IgM - antibody that responds immediately

Humoral immunity1
Humoral Immunity

2. IgG - antibody that has “memory” and recognizes a repeatedly invading infection

3. IgA - antibody present in the mucous membranes

4. IgE - antibody contributing to allergic and anaphylactic responses

5. IgD - antibody present in the lowest concentration

Humoral immunity2
Humoral Immunity

  • Begins with exposure of the body to an antigen. The antibodies seek out the invading antigen and combine, forming what is commonly called the antigen-antibody complex. This large complex is subsequently removed by scavenger cells such as macrophages.

Humoral immunity3
Humoral Immunity

  • If the body has never been exposed to a particular antigen, the reaction is totally different.

  • Initial response to an antigen is called the primary response. It takes the cellular and humoral components several days to respond to a primary antigen exposure. But other antibodies assist and develop memories of the particular antigen.

Humoral immunity4
Humoral Immunity

  • This way when the body is exposed to the same antigen again there is a secondary response which is much faster than the original.


  • Initial exposure of an individual to an antigen is referred to as sensitization.

  • This results in an immune response. Subsequent exposure induces a much stronger secondary response

  • Hypersensitivity is an unexpected and exaggerated reaction to a particular antigen, resulting in some discomfort for the individual


  • Hypersensitivity is often used synonymously with the term allergy.

  • Two types of hypersensitivity reactions:

    1. Delayed

    2. Immediate

Delayed hypersensitivity
Delayed Hypersensitivity

  • Result of cellular immunity and does not involve antibodies.

  • Occurs in hours and days following exposure

  • Most commonly results in skin rash and is often due to exposure to certain drugs and chemicals

  • Common example: rash from poison ivy

Immediate hypersensitivity
Immediate Hypersensitivity

  • Examples of immediate hypersensitivity include: hay fever, drug allergies, food allergies and asthma.

  • Some individuals have an allergic tendency, known as atopy. This is usually genetic and characterized by the presence of IgE

  • An antigen that causes the release of IgE is referred to as an allergen

Immediate hypersensitivity1
Immediate Hypersensitivity

  • After exposure to an allergen, large quantities of IgE are released.

  • IgE becomes attached to membranes of basophils and mast cells

  • Basophils and mast cells are specialized cells of the immune system which contain chemicals that assist in the immune response.

Immediate hypersensitivity2
Immediate Hypersensitivity

  • When the allergen binds to IgE attached to the mast cells and basophils these cells release histamine, heparin.

  • Mast cells and basophils are referred to as granulocytes and histamine are stored in the granules of basophils and mast cells.

  • The release process of these substances is referred to as degranulation

Immediate hypersensitivity3
Immediate Hypersensitivity

  • The reaction that takes place is referred to as an allergic reaction.

  • Histamine is the principal chemical mediator of an allergic reactions.

  • Histamine causes bronchoconstriction, increased intestinal motility, vasodilation, and increased vascular permeability.

Immediate hypersensitivity4
Immediate Hypersensitivity

  • This increased permeability is what causes the leakage of fluid from the circulatory system into the surrounding tissue.

  • Two classes of histamine receptors:

    1. H1 cause bronchoconstriction and contraction of the intestines

    2. H2 cause peripheral vasodilation and secretion of gastric acids

Immediate hypersensitivity5
Immediate Hypersensitivity

  • The goal of histamine release is to limit the body’s exposure to the antigen

  • Bronchoconstriction decreases the possibility of the antigen entering through the respiratory tract

  • Increased gastric acid production helps destroy ingested antigen

Immediate hypersensitivity6
Immediate Hypersensitivity

  • Increased intestinal motility serves to move the antigen quickly through the GI system with minimal absorption

  • Vasodilation and capillary permeability help remove the allergen from the circulation where it has the potential to do the most harm


  • Usually occurs when a specific allergen is injected directly into the circulatory system.

  • The allergen is distributed widely throughout the body.

  • It then interacts with both basophils and mast cells, resulting in massive dumping of histamine.


  • Principle body systems affected by anaphylaxis are the skin, respiratory system, cardiovascular system, GI system and the nervous system.

  • Histamine causes widespread peripheral vasodilation, as well as increased permeability of the capillaries.


  • Because of this permeability and the resultant leakage people actually die from circulatory shock.

  • Another substance called slow-reacting substance of anaphylaxis is responsible for the spasms of the bronchioles

Clinical features of anaphylaxis
Clinical Features of Anaphylaxis

  • S&S begin within 30-60 seconds following exposure

  • Severity of reaction is related to the speed of onset of symptoms

  • The faster the reaction the greater the severity

  • Itching and hives are the most common manifestations


  • Initial assessment: A-B-C

  • Then followed by a detailed assessment

Initial assessment
Initial Assessment

  • Evaluate the airway, most airway problems are associated with laryngeal edema. Take the necessary steps to manage the airway, including intubation or a surgical airway.

  • Evaluate breathing. Rate and depth. Lung sounds. Effort

  • Evaluate circulation. Pulse rate and strength. Blood pressure.

Initial assessment1
Initial Assessment

  • Evaluate neurological status: A-V-P-U

Detailed assessment
Detailed Assessment

  • Concentrate on the skin, the respiratory system, the cardiovascular system and the GI system.

  • Assess for abnormalities and treat as indicated.


  • Airway Management

  • Shock position

  • Maintain body temperature

Fluid and pharmacology
Fluid and Pharmacology

  • Fluid replacement is critical in preventing hypovolemia and hypotension, initiate at least 1 IV of NSS.

  • Principle treatment is pharmacological, which include:

    1. Epinephrine

    2. Antihistamines

    3. Corticosteroids


  • Primary medication for anaphylaxis.

  • Reverses the effects of histamine

  • Dose: .3-.5 mg (1:1,000) SQ

  • In severe cases .3-.5 mg (1:10,000) IV


  • Second-line agents in anaphylaxis.

  • Block additional histamine from binding with the receptor sites.

  • Dephenhydramine (Benadryl) is the most frequently used antihistamine

  • Dose 25-50 mg slow IV push, or deep IM


  • Adjunct therapy, to help suppress the inflammatory response associated with anaphylaxis.

  • Most common Methylprednisolone (Solu-Medrol)

  • Dose 125-250 mg, IV or IM