Immunology

What is the main goal of the immune system?

Destruction or inactivation of pathogens, abnormal cells, and foreign molecules such as toxins

What system is primarily involved in allergic reactions?

The immune system

What is cellular immunity?

Direct attack of a foreign substance by specialized immune system cells

How does cellular immunity destroy foreign substances?

By physically engulfing and deactivating them

What process is an example of cellular immunity?

Phagocytosis

What is humoral immunity?

A chemical attack against invading substances using antibodies

What are immunoglobulins?

Antibodies used by the immune system

How many types of immunoglobulins are there?

Five

Which immunoglobulin is most important for paramedics?

IgE

What does an allergen attach to during an allergic reaction?

IgE on basophils and mast cells

What is produced when an allergen attaches to IgE?

Histamine

What does histamine cause?

Bronchoconstriction, increased intestinal motility, vasodilation, and increased vascular permeability

What respiratory effect does histamine cause?

Bronchoconstriction

What vascular effects does histamine cause?

Vasodilation and increased vascular permeability

What GI effect does histamine cause?

Increased intestinal motility

What can histamine release lead to?

Allergic reactions and anaphylaxis

What is anaphylaxis?

A severe allergic reaction with rapid onset

How quickly can anaphylaxis occur?

Within 30-60 seconds

What is the relationship between reaction speed and severity in anaphylaxis?

The quicker the reaction, the more severe it tends to be

What feeling is commonly associated with anaphylaxis?

A feeling of impending doom

What airway complications can occur during anaphylaxis?

Laryngeal edema, laryngospasm, and complete airway obstruction

What respiratory findings are associated with anaphylaxis?

Tachypnea, wheezing, and progressively diminished lung sounds

What skin findings are associated with anaphylaxis?

Diffuse rash and hives

What are hives?

Raised skin lesions associated with allergic reactions

What cardiac intervention should be considered in anaphylaxis?

Cardiac monitoring

What airway intervention should be considered early in anaphylaxis?

Early intubation

What vascular intervention should be performed in anaphylaxis?

IV access with fluids

What is the first-line medication for anaphylaxis?

Oxygen

What is the adult IM epinephrine dose for anaphylaxis?

Epinephrine 1:1,000, 0.3-0.5 mg IM every 15-20 minutes

What IV epinephrine dose may be used for anaphylaxis?

Epinephrine 1:10,000, 0.1 mg IVP over 5 minutes

What medications may be given in addition to epinephrine during anaphylaxis?

Benadryl, steroids, albuterol, and vasopressors

What is distributive shock?

A shock state caused by massive and prolonged vasodilation

What type of problem is distributive shock?

A pipes problem

Why is distributive shock considered a pipes problem?

Because the shock state is caused by vasodilation

Is distributive shock primarily a fluid problem?

No

What are the main types of distributive shock?

Neurogenic shock, anaphylactic shock, and septic shock

What causes neurogenic shock?

Loss of normal vasomotor tone due to an unopposed parasympathetic response

What happens to blood vessels in neurogenic shock?

Massive vasodilation occurs

What are the hallmark signs of neurogenic shock?

Hypotension and bradycardia

What fluid bolus is recommended for neurogenic shock?

20 mL/kg PRN

What is anaphylactic shock?

The most extreme form of anaphylaxis

What are the signs and symptoms of anaphylactic shock?

Hypotension, tachycardia, bronchoconstriction, edema, and dyspnea

What fluid bolus is recommended for anaphylactic shock?

10-20 mL/kg PRN

What type of shock can anaphylaxis progress to?

Anaphylactic shock

What is septic shock?

A severe form of systemic inflammatory response syndrome (SIRS)

What can septic shock lead to?

Severe organ dysfunction and death

What are the signs and symptoms of septic shock?

Hypotension, tachycardia, edema, altered mental status, fever, and dyspnea

What fluid bolus is recommended for septic shock?

20 mL/kg PRN

Why does septic shock have a high mortality rate?

Profound circulatory, cellular, and metabolic abnormalities increase the risk of death

What does septic shock ultimately lead to?

Cardiorespiratory failure

What type of distributive shock presents with hypotension and bradycardia?

Neurogenic shock

What type of distributive shock presents with hypotension, tachycardia, bronchoconstriction, and edema?

Anaphylactic shock

What type of distributive shock presents with hypotension, tachycardia, fever, altered mental status, and dyspnea?

Septic shock

What immunoglobulin is responsible for allergic reactions and anaphylaxis?

IgE

What process is commonly compared to PacMan in the immune system?

Phagocytosis

What immune response relies on antibodies?

Humoral immunity

What immune response relies on specialized cells physically attacking foreign substances?

Cellular immunity

What mediator is primarily responsible for the symptoms of allergic reactions?

Histamine

What severe allergic reaction can cause complete airway obstruction?

Anaphylaxis

What type of shock is caused by widespread vasodilation rather than fluid loss or pump failure?

Distributive shock