Basic types of inflammation

Basic types of inflammation are:

1. acute

2. subacute

3. chronic

Acute inflammation

1. the injury is healed in two to three weeks & most of the time no permanent damage occurs

2. the most prominent cell types are neutrophils

Subacute inflammation

1. consists of same appearance as acute

2. takes 2 wks to months to heal

Chronic inflammation

1. can last for months to years

2. it can start out when the acute inflammation is unable to remove foreign agent

3. the offending agent repeatedly injures tissue (s)

4. the most common cells are lymphocytes & macrophages

5. examples: rheumotoid arthritis (RA) & tuberculosis (TB )

6. process of continually having to fight the inflammation over extended time period can lead to immune dysfunction

Reconstruction – next phase of healing, has ability to intersect with inflammation phase

1. desired effect is that the tissue will be the same type & function as original tissue

2. simple resolution occurs when there is no devastation to the original tissue & body is able to successfully remove the cause

3. another type of resolution is "regeneration'

   a. the tissue is able to replace the original tissue with new tissue

   b. this varies by the type of tissue and cell type

   c. labile cells are able to restore themselves throughout life

*the cells are found where there is a constant change in the cells. ie. epithelial, bone marrow, mucous membranes, cervix, GI tract

d. stable cells continue to replace themselves until growing stops but they do have ability to

replace themselves if injury occurs

examples are osteocytes & parenchymal cells of kidneys, liver, & pancreas

Permanent or fixed cells

1. unable to replace themselves

2. when these cells are injured, they are replaced ("repair") with scar tissue

3. difference is tissue that has been repaired & can no longer function as it did previously

4. the wound is filled with scar tissue which provides tensile tissue strength

5. ie. nerve cells, skeletal muscles, cardiac muscle

Repair – more complex process that occurs by primary, secondary, or tertiary intention

1. primary intention

   a. occurs when the edges of the skin are well approximated

   b. wound is clean

   c. there is a small amount of tissue damage

   d. can occur naturally such as with a paper cut

   e. can occur with sutures

   f. glu (dermabond)

   g. staples (read stages of wound healing, pg 76 lemone)

2. secondary intention

   a. occurs when the wound has large, wide, jagged edges

   b. a lot of tissue damage

   c. these wounds can occur from trauma, infection, or ulceration

   d. inflammatory phase of the healing process may be more intense resulting in↑amount of

exudates, debris, & cells

e. this is where they might do I & D (irrigation & debridement)

f. this debris must be removed prior to healing

Primary Intention wound / incision becomes infected ie. splinter

1. wound will have to heal by secondary intention

2. wound heals from outer edges & from base to top & filled

3. because of the way it has to heal, greater amount of scar tissue results in larger scar