Wound Healing

Question 1

when does the inflammatory stage occur?

Answer 1

approximately day 0-5

Question 2

when does the proliferation phase occur?

Answer 2

approximately day 4-12

Question 3

what does the proliferation phase involve?

Answer 3

collagen production
capillary ingrowth
wound coverage
wound contraction

Question 4

what is ground substance secreted by?

Answer 4

fibroblasts

Question 5

when does epithelialization occur?

Answer 5

with no defect, begins immediately
with granulation tissue, begins day 4-5

Question 6

what is granulation tissue a source of?

Answer 6

myofibroblasts
contract over tissue

Question 7

what are myofibroblasts?

Answer 7

special fibroblasts transformed by TGF-beta

Question 8

what do myofibroblasts do?

Answer 8

fibroblasts: secrete and synthesize collagen
smooth muscle characteristics: contractile

Question 9

when does the maturation phase occur?

Answer 9

begins day 17-20
may continue for 12-18 months

Question 10

does wounded tissue eventually achieve original strength?

Answer 10

no
50-80% of normal

Question 11

what factors affect wound healing?

Answer 11

blood supply/vascular perfusion/anemia: systemic factors
tissue viability
wound fluid accumulation
mechanical factors
foreign material
drugs
infection

Question 12

what are some systemic factors that affect wound healing?

Answer 12

immunodeficiency
cancer
age/older animals: decreased fibroplasia

Question 13

what are some drugs that affect wound healing?

Answer 13

steroids and NSAIDs
for first stage of healing

Question 14

what does exudate do in tissues in wounds?

Answer 14

separates tissues

Question 15

why is wound infection bad for healing?

Answer 15

exudate separates tissues
necrosis due to bacterial enzymes and toxins
more debridement to remove necrotic material
prolonged inflammatory stage
delay or repair phase

Question 16

what are the surgical wound classifications?

Answer 16

clean wound
clean-contaminated wound
contaminated wound
dirty wound

Question 17

what is a contaminated wound?

Answer 17

open traumatic wounds
major break in sterile technique
spillage of GI contents or infected urine

Question 18

what is delayed primary closure?

Answer 18

limited contamination
leave unsutured with dressing
close if clean day 3-5
minimal granulation tissue present

Question 19

what is secondary closure?

Answer 19

contaminated wounds
open wound management
appositional closure more than day 5 after wound
direct skin apposition over granulation tissue

Question 20

when is second intention healing useful?

Answer 20

dirty and infected wounds

Question 21

when is adnexal reepithelialization useful?

Answer 21

cutaneous burns and abrasions

Question 22

what are the methods of closure?

Answer 22

3-7 days after initial injury
may or may not even need closure
secondary closure
skin grafts
skin flaps

Question 23

what diagnostics should you perform on draining tracts?

Answer 23

radiographs
fistulograms
ultrasound
CT
culture and biopsy tissue

Question 24

when might you see non-healing wounds?

Answer 24

older or younger patients
concurrent disease
poor nutritional status
chronic inflammation
low-grade infection
repeated trauma to wound
chronic wet-to-dry bandages

Question 25

should all seromas be drained?

Answer 25

small ones can be warm packed large ones must be drained

Question 26

what should you do in bite wound exploration?

Answer 26

clip area widely open puncture with scalpel blade hemostat to probe and examine area excise necrotic tissue copious lavage drain placement and close

Question 27

what should you not do with hygromas?

Answer 27

excise

Question 28

what happens in the inflammatory stage?

Answer 28

hemorrhage vasoconstriction then vasodilation fibrin inflammatory mediators present first 5 days

Question 29

what is happening in granulation tissue?

Answer 29

capillary ingrowth ground substance collagen from fibroblasts collagenases

Question 30

what type of attachments do myofibroblasts have?

Answer 30

cell-to-cell cell-to-stromal

Question 31

when does contraction of myofibroblasts begin?

Answer 31

days 8-15

Question 32

what happens with collagen in the maturation phase?

Answer 32

changed from type III to type I

Question 33

what do steroids do that decrease wound healing?

Answer 33

prostaglandins are chemokines for fibroblasts into wound decrease edema, fibrin deposition, and capillary dilation decrease capillary proliferation

Question 34

what is mandatory if the abdominal cavity is entered with bite wounds?

Answer 34

exploratory surgery