Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
56 Cards in this Set
- Front
- Back
|
define wound?
define regeneration? define repair? |
any disruption to anatomic and/or physiologic fxn tissue
replacement of lost cells with cells similar in fxn and structure proliferation of connective tissue elements leading to formation of a collagenous scar |
|
|
what type of cells have very good regenerative capacity?
what are examples of this cell type? |
labile cells
ex. epithelium, bone marrow cells |
|
|
what cells regenerate well as long as tissue outline is maintained during inflammatory process?
what are examples of this cell type? |
stable cells
ex. glandular cells, liver parenchymal cells, MESENCHYMAL CELLS |
|
|
what is another name for mesenchymal cells
|
supportive cells
|
|
|
what are types of mesenchymal cells?
|
-fibroblasts
-smooth muscle -vascular endothelial cells -bone cells and cartilage cells |
|
|
what are the major components of the extracellular matrix
|
collagens, proteoglycans and adhesive glycopro's
|
|
|
why is the extracellular matrix so impt for wound healing?
|
provides the framework for cell migration
and also maintains the correct cell orientation for re-assemble of multilayer structures |
|
|
what is an example of a regeneration of stabile cells?
|
increased growth of remaining liver tissue after hepatectomy
|
|
|
what cells have no regenerative capacity?
give examples of this cell type |
permanent cells
ex skeletal muscle, cardiac muscle, some nerve cells in CNS |
|
|
what is a new discovery of adult brain cells
|
can produce new neurons
|
|
|
what are the three major phases of wound healing?
|
1.inflammation
2.proliferation 3.maturation |
|
|
what is inflammation phase characterized by?
|
1.clot formation
2.acute inflammation 3.macrophage infiltration |
|
|
what is the proliferation phage characterized by?
|
1. development of granulation tissue
2.Fxn of granulation tissue 3.Regeneration of epidermis |
|
|
what is the term granulation derived from?
what components develop in granulation tissue? |
granular appearance of wound surfaces
new vessels and proliferating fibroblasts |
|
|
what is the process of new vessel formation called?
|
angiogenesis
|
|
|
what is the fxn of the new vessels formed in granulation tissue
|
provide nutrition for regerating tissues
|
|
|
what produces all of the wound collagen y the end of the proliferation phase?
|
fibroblasts
|
|
|
what is the maturation phase?
|
remodeling of collagen and development of wound strength
|
|
|
what happens to the wound during the maturation phase?
what is maximal strength of the wound |
it contracts toward center to decrease in size
70-80% of strength of original unwounded skin |
|
|
what two layers make up the Skin?
what are the underlying layers of skin? |
epidermis and dermis
subcutaneous tissue, then fascia, muscle and bone |
|
|
which layer of skin is nonvascular?
what is the dermis composed of? |
epidermis
collagen and connective tissue |
|
|
what appendages are present in the dermis?
|
sweat glands, sebaceous glands and hair follicles
|
|
|
what layer of skin has many blood vessels to provide oxygen and nutrients?
|
dermis
|
|
|
what is fxn of subcutaneous tissue?
|
shock absorber and heat insulator, also reseves calories
|
|
|
what are the 4 fxns of skin?
|
1.protection from bacteria and environmental hazards
2.thermoregulation 3.produce vit D 4.sensory transmitter |
|
|
what is meant by "primary wound healing"?
|
clean, uninfected surgical incision
|
|
|
what are the temporal sequece of steps involved with primary wound healing?
|
same 3 as normal wound healing(inflammate,proliferate,maturate) but faster b.c only mild tissue destruction
|
|
|
what happens immediately in primary wound healing?
|
incision fills with clotted blood then scab
|
|
|
what happens within 24 hours of prim. wound?
|
neutrophils migrate to margins of incision and cut edges of epidermis thicken
|
|
|
hat happens within 24-48 hours of prim wound
|
thin continuous epithelial cell layer forms beneath scab
|
|
|
what happens by day 3 of prim wound
|
a. macrophages replace neutrophils
b. granulation tissue progressively invades incisional space |
|
|
what happens day 5 of primary wound?
|
a. incisional space begin to bredge incision
b. epidermal layer becomes normal thickness with matrue differentiation |
|
|
what happens during 2nd week of primary wound
|
a.fibroblasts proliferate and continue to produce collagen
b.blood vessels in granulation tissue disappear c.scar begins to lighten |
|
|
what happens after 1st month of prim wound healing
|
a. compact dermal scar covered by intact epidermis
b.dermal appendages destroyed in line of incision have been permanently lost |
|
|
what happens in following months of prim wound healing
|
addition and remodeling of collagen to strenthen wound
|
|
|
what are examples of secondary wound healing
|
large, infected surface wound
inflammatory ulceration, infarction or very small laceration |
|
|
what is the key difference between primary and secondary wound healing?
why? |
secondary wound healing is left to heal by itself
wound is too big to close, is infected, and/or is necrotic OR: wound is so small it can close on its own |
|
|
what are other differences b/w primary and secondary if the wound is large?
|
large wounds have more:
-inflammation -granulation tissue -epithelial regeration -WOUND CONTRACTION - |
|
|
which type of healing results in a larger scar?
which healing takes more time |
secondary
secondary |
|
|
what are systemic factors impairing wound healing?
|
-nutritional deficiency
-inadequate blood supply -diabitese mellitus DM -steroid hormones -immunocompromised patients(HIV) |
|
|
what type of deficiency inhibits collagen synthesis?
|
PRO and VIT C
|
|
|
what are three problems assoc with DM
|
1.impaired blood supply to wounds
2. decreased sensation in extremities 3.impaired immune fxn |
|
|
what do steroid hormones inhibit?
|
inflammatory process and collagen synthesis
|
|
|
what blocks arachadonic acid?
what does this in turn block production of? |
steroid hormones
prostaglandin and leukotriene |
|
|
what are three possible complications of wound healing?
|
1.assembly of scar
2.excessive formation of components of repair process 3.formation of wound contractures |
|
|
what is wound dehiscence?
why does this occur? |
wound opens
increased abdominal pressure(cough, vomit, etc.) most common after surgery |
|
|
what are predisposing conditions to ulceration?
|
1.inadequate blood supply due to atherosclerosis
2.imparied sensation in extremities |
|
|
what is an incisional herniation?
what is this due to? |
bulging sac within healing or healed abdominal incision
abdominal pressure |
|
|
what are possibilities from excessive formation of components of repair process?
|
1.hypertrophic scar
2.keloid |
|
|
what is a raised scar?
what is it caused by? |
hypertrophic scar
caused by excessive collagen |
|
|
what causes a keloid?
what can this sometimes be? |
excessive collagenous protrusion at scar site
disfiguring due to going beyond boundaries of original wound |
|
|
what population has an increased occurence of keloids
|
African Americans
|
|
|
when are formation of wound contractures commonly seen?
what can they result in? |
after burns
deformities of an areas as well as LIMITATION OF MOTION AT A JOINT |
|
|
what happens with the formation of adhesions?
give examples. |
inflamed serosal surfaces bind together
ex. collagenous adhesions b/w inflamed loops of bowel |
|
|
what are sutue therapy complications?
|
1. sutures may be source of infection
2. premature suture removal prolongs healing process |
|
|
what determines the pathway of repair (4)?
|
1. is stimulus promptly destroyed
2.presence and extent of cell necrosis 3.intactness of stroma 4.regenerative capacity of injured cells |
