6: wound healing

Question 1

3 layers of the skin

Answer 1

Epidermis
hypodermis
dermis

Question 2

Series of thin muscles under the skin in dogs and cats

Answer 2

panniculus

Question 3

Why is the panniculus so important during surgery

Answer 3

failure to preserve will cause loss of blood supply and wound dehiscence

Question 4

provide blood supply to skin

run parallel to skin

Answer 4

Cutaneous arteries

Question 5

Major blood supply to the skin

Answer 5

subdermal plexus

Question 6

Why is the subdermal plexus important

Answer 6

must be preserved to maintain blood supply

Question 7

Coagulation times

Answer 7

<5 min

Question 8

Inflammatory stage time

Answer 8

0-24 hours

Question 9

debridement stage time

Answer 9

2-5 days

Question 10

Repair stage

Answer 10

4-21 days

Question 11

Maturation stage times

Answer 11

21 days - 2 years

Question 12

3 stages of primary coagulation

Answer 12

1. damaged endothelium exposes collagen fibers to blood elements
2. Biding of subendothelial collagen with von Willebrand factor
3. Platelets form platelet plug

Question 13

Secondary coagulation

Answer 13

series of factors react resulting in formation of fibrin meshwork around wound

Question 14

Intrinsic path numbers

Answer 14

12, 11, 9, 8

Question 15

Extrinsic pathway numbers

Answer 15

3, 7

Question 16

Common path numbers

Answer 16

10, 5, 2, 1

Question 17

Which is necessary for wound healing, macrophages or neutrophils

Answer 17

macrophages

Question 18

First leukocyte to enter wound
numbers increase from 24-48 hours
degrade and clear bacteria

Answer 18

Neutrophils

Question 19

Required for healing of wounds
predominate 2-5 days after injury
phagocytize necrotic tissue

Answer 19

Macrophages

Question 20

Removal of necrotic tissue and debris by macrophages

Most important thing we can do to help heal a wound

Answer 20

debridement

Question 21

End of debridement stages is characterized by influx of

Answer 21

fibroblasts into the wound

Question 22

what marks the proliferative stage

Answer 22

influx of fibroblasts

rapid accumulation of collagen

Question 23

when epithelial cells proliferate and move across a wound until they contact each other

Answer 23

contact inhibition

Question 24

Cells that contain actin and myosin fibers that exert tensile forces on the ECM resulting in closure of the defect

Answer 24

Myofibroblasts

Question 25

How does collagen remodel

Answer 25

according to tensile forces

Question 26

How is tensile strength changed during maturation phase

Answer 26

minimally

Question 27

How does the source of wound strength change over time

Answer 27

as the suture starts to absorb, the tissue strength should increase

Question 28

Intrinsic wound factors (7)

Answer 28

``` hypoproteninemia anemia malnutrition uremia diabetes mellitus hyperadrenocroticisim infection ```

Question 29

Extrinsic wound factors (4)

Answer 29

mechanism (shear, crush) foreign material irradiation antiseptics

Question 30

How are wounds classified

Answer 30

based on time and contamination

Question 31

Class 1 wound

Answer 31

0-6 hours | minimal contamination

Question 32

Class 2 wound

Answer 32

6-12 hours | moderate contamination

Question 33

Class 3 wound

Answer 33

>12 hours gross contamination never close

Question 34

Clean wound

Answer 34

surgical procedure | not entering GI or respiratory tract

Question 35

Clean-contaminated surgery

Answer 35

GI or respiratory tract entered | minor break in asepesis

Question 36

Contaminated surgery

Answer 36

Gi with gross contamination, inflammation major break in sepsis

Question 37

Dirty surgery

Answer 37

devitalized or necrotic tissue gross debris Pus

Question 38

When should you use antimicrobials

Answer 38

``` class 2-3 wound Clean-contaminated to dirty surgeries ```

Question 39

What should you always do with bite wounds

Answer 39

open them

Question 40

First step in addressing an open wound

Answer 40

clip the fur and put sterile lube on it

Question 41

First and most important aspect of contaminated wound treatment

Answer 41

removal of trash via mechanical lavage using saline

Question 42

after removal of trash you should

Answer 42

debride the wound

Question 43

Wet bandages

Answer 43

1. layer of saline soaked gauze 2. dry laparotomy sponges on top 3. vet wrap over all of it

Question 44

active drain

Answer 44

preferred just for support make vacuum in wound to remove fluid

Question 45

Passive drain

Answer 45

gravity | 2-5 days at most

Question 46

Wound closure stages

Answer 46

Primary Delayed primary late secondary second intention

Question 47

Primary would closure

Answer 47

immediate closure of wound | <6 hours

Question 48

Delayed primary wound closure

Answer 48

after 6 hours | before granulation >2 days

Question 49

Late secondary wound closure

Answer 49

after appearance of granulation tissue >2 days

Question 50

Second intention wound closure

Answer 50

no surgical closure | dependent on wound healing