3220: wound healing

• - parenchymal 
• - stromal

working cells that are doing whatever that particular organ does

structural net hols the parenchymal tissue in place [supplies it with nutrients and gives i structure], structures tissue

• - regeneration of dead parenchymal working class
• - connective tissue repair

• - primary intention 
• - secondary intention

• 1. inflammatory response [clean up phase]
• 2. proliferative [reconstruction phase]
• 3. remodeling [maturation phase]

make more of the same thing

become more specialized for a specific function

in-differentiated cells, can make many type of cells

• -continuously dividing cells
• - stable cells
• - permanent cells

• constantly replaced 
• - such as the skin, bone marrow, and linings. must have bank of stems

• normally stop dividing, held in quiet stage of cell cycle, but can turn on production as stimulated 
• - smooth mucle, parenchyma, fibroblasts

• - no proliferation, very differentiated
• - nerves, heart muscle

chemical mediators, and growth factors

in the extracellular matrix

due to collagen deposition which creates a strong bond to hold the area together

• - they are extra scar tissue that can cause that sticks to other organs etc. their not supposed to 
• - functional problems and discomfort and also a pulling sensation

2 days - 3 weeks +

• - angiogenesis 
• - firoblasts and ECM depositions 
• - maturation and remodeling

• - first phase of scar formation 
• - angiogensis: formation of new baby blood vessels, need Nitric oxide 
• - granulation: tissue fills in, made of new capillaries, fibroblasts, and inflammation tissue

• - red
• - moist
• - meaty looking
• - granular
• - bleed easily, puffy

• - fibroblasts secrete collagen in fibrous strands
• - collagen created a scaffold of strength 
• - other ECM deposited in wound
• - in skin wounds, epithelial cells seal wound in 24-48 hours, "approximated" wounds heal faster, epitheliaization is the bridging of the would with skin (epithelial) cells

• - scar matures, blood vessels retreat, scar turns paler, avascular, with stress lines
• - tensile strength increases 70% with sutures, to 10 % increases up to 70 or 80 by three months

• - is your basic, good, fast healing 
• - not a lot of missing or dead cells to replace, edges of would come together, no foreign bodies, dirt, infection

is complicated, missing, chunks, infected, foreign bodies, edges of would don't come together

they use the "REEDA" tool

• it stands for
• - redness
• - edema
• - ecchymosis
• - drainage 
• - approximation

• - nutritional deficiencies
• - inadequate blood supply 
• - disease 
• - poor circulation 
• - corticosteriod drugs
• - infection 
• - mechanical friction on wound
• - advanced age
• - obesity 
• - poor general health

• Vit C and protein deficiencies can 
• - prevent formation of collagen fibers
• - decreases supply of amino acids for tissue repair

• - decreases supply of nutrients/ oxygen to injured area
• - decreases removal of exudative debris
• - inhibits inflammation response

• - depresses the formation of granulation tissue 
• - inhibits wound contraction

increases inflammatory reponse and tissue destruction

• - destroys granulation tissue
• - prevents apposition of wound edges

• - slows the formation of collagen by fibroblasts
• - impaired circulation

- decreases blood supply to fatty tissue

- generalized absense of factors necessary to promote wound healing

• - hypertonic oxygen
• - nutrition
• - debridment 
• - prevent/treat infections
• - control diseases like diabetes
• - enhance circulation

• - keloid
• - dehiscence 
• - evisceration 
• - contracture

• a type of abnormal wound healing
• - wound opens up again which leads to healing via secondary intention rather than primary intention which is not ideal

• a type of abnormal wound healing 
• - its where the wound opens up in the abdominal area and guts fall out
• - usually in obese pts or pts with infections

• a type of abnormal wound healing
• - adhesion formation when the wound contracts, the scar tissue wont stretch anymore and can limit the movement of that area