Bafl Exam 3: Wound Healing

Front 1

Three stages of acute wound healing?

Back 1

Inflammation

Proliferation

Remodeling

(some sources say that there are four phases, to include hemostasis initially)

IPR!!!!

Front 2

When does the dermis shift from non scarring to scarring wound repair?

Back 2

end of second trimester

Front 3

Main player in hemostasis/coagulation?

Back 3

platelets

Front 4

Main player in inflammatory process?

Back 4

neutrophil

Front 5

Main player in migration/proliferation process?

Back 5

macrophage

Front 6

mAIN PLAYER IN REMODELING PROCESS?

Back 6

FIBROBLASTS

Front 7

Difference between repair and regeneration?

Back 7

Repair- inflammation, proliferation, remodeling, partial thickness and full thickness wounds heal by this

Regeneration- completely restoring tissue to the way it was before injury, epidermal erosion healing only

Front 8

Primary vs Secondary vs Tertiary intention healing?

Back 8

Primary- wound edges are directly next to eachother, little tissue loss, minimal scaring occurs, sutures

Secondary- wound is allowed to granulate in, healing process can be slower

Tertiary- delayed primary, wound is observed for 4-5 days before closure

Front 9

Three over lapping phases of wound healing... generalized time frames?

Back 9

IPR

Inflammatory- starts immediately after injury, lasts 1-2 days (remember, the neutrophil is most important here)

Proliferative- reepitheliazation within first 24 hours of injury starts, but this is really going strong around day 4 (macrophages are the main player in this)

Remodeling- contraction via myofibroblasts, begins around 2 weeks (this is when fibroblasts differentiate into myofibroblasts)

Front 10

Fibroblasts produce fibronectin after injury... what does fibronectin do?

Back 10

allows fibroblasts to clot and migrate

Front 11

Platelets do more than just clot! They release growth factors... which are the most important and why?

Back 11

PDGF (platelet derived growth factor)

**TGF-B (transforming growth factor)-- platelets are the most important storage site

PDFG and TGF-B are potent PMN chemoattractants, help initiate angiogenesis

Front 12

What are the pathways in coagulation (general)?

Back 12

Intrinsic- activated by contact when blood is exposed to subendothelial tissue, leading to activation of factor X

Extrinsic- damaged tissue releases tissue factor (TF)

Final common pathway converges on thrombin to convert fibrinogen to fibrin, activates VIII, V, protine C and factor XIII

Front 13

Initial tethering of leukocytes is caused by what?

Back 13

L selectin (on leukocytes)

E selectin (on endothelial cells)

P selectin ( endothelial cells and platelets)

Front 14

Where is P selectin in the platelets? In the endothelial cells?

Back 14

Remember, P is on both the endothelial and platelets

L is on Leukocytes

E is on Endothelial

Platelets have P selectin in alpha granules

Endothelial cells have P selectin in Weibel Palade bodies

Front 15

What is responsible for vasoconstriction in initial injury?

Back 15

Serotonin

Front 16

What are the mediators of vasodilation in wounds?

Back 16

Bradykinin

PGE2

Front 17

Matrix metalloprotinases produced by cells clear a path for fibroblasts to migrate into the wound... deficiency of what would halt this process?

Back 17

MMPs are zinc and calcium dependent

MMP1 (collagenase)

MMP2, 9 (gelatinase)

MMPp 3 (stromelysin)

Front 18

How long after BM reconstruction begins does it return to normal?

Back 18

7-9 days

collagen IV (most abundant), collagen VII, collagen XVII, laminin

Front 19

Proliferation and migration of fibroblasts is stimulated by...

Back 19

low pH, HYPOXIA

Front 20

Excess of what leads to keloid formation?

PDGF

TGFB

FGF

EGF

Back 20

TGFB a/w keloid formation

Front 21

Fibroblasts differentiate into myofibroblasts at which week (for contraction)?

Back 21

week 2

Front 22

Which collagen predominates in wound healing?

Back 22

III (replaced by I)

Front 23

Do keloids contain more or less myofibroblasts than normal scars?

Back 23

LESS- but they are PERSISTENT

Front 24

Zones that heal well via secondary intention?

Back 24

NEET!

NOSE, EAR, EYE, TEMPLE

Front 25

ABI in peripheral arterial disease?

Back 25

<0.9

Front 26

Stages of graft healing?

Back 26

Imbibition: 48 hours, sustained by plasma exudate, ischemic period (graft is a dusky blue and looks like crap)

Inosculation: 2-3 days, vessels contract

Neovascularization: 1 week, new vessels (graft turns pink--> if this happens, it will survive)

Maturation: months, sensory innervation returns

Front 27

How much protein during wound healing?

Back 27

more than 1mg/kg/day

Front 28

Meds that inhibits wound healing?

Back 28

corticosteroids

penicillamine

NSAIDs

nicotine

Front 29

Best dressing for a really exudative wound?

Back 29

alginate

Front 30

Dressings for increasing exudate?

Back 30

worst to best

hydrogel --> film --> hydrocolloid --> foam --> alginate

Front 31

Tensile strength by:

1 week

Back 31

1 week 5%

Front 32

Tensile strength by:

2 weeks

Back 32

2 week 10%

Front 33

Tensile strength by:

3 weeks

Back 33

3 week 20%

Front 34

Tensile strength by:

4 weeks

Back 34

40%

Front 35

Tensile strength by:

8 weeks

Back 35

8 weeks, 80%

Front 36

Which keratins are increased in wound healing?

Back 36

K6/16

Front 37

When treating an acute wound, which characteristic of an occlusive dressing is most important?

Back 37

moisture rention

occluded wounds heal 40% faster!

Front 38

What needle size is most commonly used for facial skin surgery?

Back 38

3/8 circle

Front 39

What are the three types of occlusive/moisture retentive dressings?

Back 39

Antimicrobial (silver, cadexomer iodine)

Non-biologic

Biologic (xenograft, allograft, autograft)

Front 40

Which dressing is the only one to show an increase in re epithelialization?

Back 40

films! (ie tegaderm)