Immunity, Inflammation, Infectious Process Flashcards
Types of Immunity
Innate resistance: Natural barriers and the inflammatory response
Adaptive (acquired) immune system
Passive (short term immunity)
First Line of Defense
Innate Immunity
Physical and mechanical barriers:
Skin and low skin temperature (prevent microorganism)
Linings of the gastrointestinal, genitourinary, and respiratory tracts
Include: Highly interconnected junction Sloughing off of cells Coughing and sneezing “Washing” Vomiting Urinating Mucus and cilia
First Line of Defense
Innate Immunity
Biochemical barriers
Synthesize and secrete substances to trap or destroy microorganisms
Ex: Antibacterial peptides in mucus, perspiration (sweat), saliva, tears, and earwax
Normal microbiome
Inhibits colonization by pathogens; releases chemicals that prevent infection
Vaginal: Lactobacillus
Second Line of Defense
Inflammatory response Causes Infection, mechanical damage, ischemia, nutrient deprivation, temperature extremes, and radiation Cellular and chemical components Nonspecific Rapidly initiated No memory cells
Cardinal signs
Redness (erythema), heat, swelling, and pain
Vascular response
Blood vessel dilation, increased vascular permeability and leakage, white blood cell (WBC) adherence to the inner walls of the vessels, and migration through the vessels
Cellular chemotaxis
Attraction of platelets and other WBCs to the site of injury
Local Manifestations of Acute Inflammation
Redness, heat, swelling, & pain
Serous exudate (transudate)/Watery exudate: Indicates early inflammation.
Fibrinous exudate
Thick, clotted exudate: Indicates more advanced inflammation.
Purulent exudate
Pus: Indicates a bacterial infection. Rich in proteins from WBCs, microbial organisms, and cellular debris.
Hemorrhagic exudate
Exudate containing blood: Indicates bleeding
Systemic Manifestations of Acute Inflammation
Inflammatory mediators are released into the circulation
Lowering of pH
Leukocytosis or Leukopenia (WBC increase)
Fever or Pyrexia
Chronic Inflammation
Causes tissue damage in common disabling diseases
Increases susceptibility to Cancer
Causes
Persistent infections or irritants
Obesity
Resolution & Repair
Regeneration
Most favorable outcome
Resolution
Returning injured tissue to an approximation of their original structure and function
Repair
Replacement of destroyed tissue with scar tissue
Scar tissue: Primarily composed of collagen to restore the tensile strength of the tissue
Healing by Primary and Secondary Intention
Primary intention –sutured surgical incision
Secondary intention- larger wounds which have a greater loss of tissue and contamination
The characteristic vascular changes at the site of an injury produce?
Increased permeability and leakage
Factors that Affect Wound Healing
Nutrition
Blood Flow & Oxygen Delivery
Impaired Inflammatory and Immune Responses
Infection, Wound separation and Foreign Bodies
Nutritional Status
Local and systemic factors influence wound healing
Vitamin C and A play an essential role in the healing process
Vitamin C is needed for collagen synthesis
Vitamin A functions in stimulating and supporting epitheilial
Possible Complications of
Wound Healing
Keloid (hyperplasia/scar tissue) Contractures Dehiscence (wound opens up) Evisceration (organ is coming out of wound. High risk: lungs, chest) Stricture (narrowing) Fistula Adhesions (scar tissue internally)
Wound Healing in the Elderly
Diminished immune function A decrease in dermal thickness A decline in collagen content Loss of elasticity Underlying illness
Adaptive Immunity
Third line of Defense
Works together with inflammation.
Recognizes foreign or “nonself” substances (Antigens)
Provides long-term protection.
Is slower than innate but more specific.
Has memory.
Active Immunity—Active Acquired Immunity
Antibodies or T cells are produced after either
a natural exposure to
an antigen or after immunization.
Is long lived.
Passive Immunity—Passive Acquired Immunity
Preformed antibodies or T lymphocytes are transferred from a donor to a recipient. Occurs naturally (placental transfer) or artificially (immunotherapy). Is temporary or short lived.
Which statement indicates the nurse has an accurate understanding concerning passive immunity?
“Can be transferred from a donor to a recipient.”
Antigen
Is a molecule that can react with antibodies or receptors on B and T cells.
Is mostly protein but can be other molecules as well.
Immunogenic antigen: An antigen that can trigger an immune response
Antibody
Is also called immunoglobulin (Ig).
Is produced by plasma cells.
Has several classes
IgG (most prevalent), IgA (Mostly in secretions), IgM (first contact/largest), IgE (most rare), and IgD (not well known)
IgG
Most of protective activity against infection
Crosses the placenta
IgA
Most of protective activity in body secretions
IgE
Mediator of many common allergic responses
Defends against parasitic infections
IgD
Functions as one type of
B-cell antigen receptor
