Vmc 932 Lecture 7 - Skin Closure

Front 1

What are the 5 types of 'skin grafts'

Back 1

Random pattern flap, axial pattern flap, free graft, microvascular free graft, musculocutaneous flap or free graft

Front 2

What are the two closure types we are dealing with

Back 2

Primary - immediate
Secondary - after formation of granulation tissue

Front 3

What is the course of action if the tissues are devitalized

Back 3

Debride, lavage, bandage
flap/graft only when a healthy granulation bed is present

Front 4

What is the blood supply to a random pattern flap, how does this affect size

Back 4

They survive via blood supply in the subdermal plexus, this limits length
due to limited length they can only be used locally

Front 5

What is a bipedicle advancement flap

Back 5

Make releasing incision in an area where the skin is a little looser, close wound and then close secondary incision (may perform one on each side of wound)
secondary site must have more loose skin than primary wound

Front 6

What is a single pedicle advancement flap

Back 6

Cut flap of equal size to wound (at least in length) advance into the wound and suture, remove any remaining 'dog ears' or allow them to recess on their own

Front 7

What is an 'H' plasty

Back 7

performing single pedicle flap on either side of the wound, each flap is half the length of the wound, the two flaps are advanced to meet in the center of the wound, remove any remaining 'dog ears' or allow them to recess on their own

Front 8

What is a rotational flap

Back 8

Often triangular wounds, semicircular incision which is rotated into wound
esp over eyelids, severe tailhead wound (bilateral rotation flaps)

Front 9

What is a transpostional flap

Back 9

A similar shape is made at a 90 degree angle to defect, flap is picked up and dropped into defect.

Front 10

How do we handle cresent shaped defects

Back 10

Longer skin edge on one side may lead to large 'dog-ear' if closed end to end, instead, start in center and go 1/2 on each side, keep halfing until closed

Front 11

How do we handle circular wounds

Back 11

Start in center, then do 1/2 on each side, keep halfing until wound is closed, trim dog ears if needed
or turn into ellipse, start in center and work out

Front 12

How do we handle triangular wounds, what becomes a problem area

Back 12

pull all 3 sides to center, suture each wing of 'flower
center becomes a problem area
may do rotational flap instead

Front 13

How do we handle square or rectangular wounds

Back 13

pull in from 4 orners in 4 lines, connect center, mtg point of 3 lines tends to be a problem area

Front 14

What is the difference between a random pattern flap and an axial pattern flap

Back 14

Axial pattern flaps incorporate direct cutaneous artery/vein and thus can be much longer than random pattern flaps

Front 15

Why should axial pattern flaps not be rotated more than 90 degrees

Back 15

worry about pinching off vessels

Front 16

Do axial pattern flaps require granulation beds

Back 16

No, they are supported by the direct cutaneous artery/vein

Front 17

What is the superficial temporal flap used for

Back 17

Rotate forward to cover facial defects

Front 18

Where does the Cervical cutaneous branch of omocervical arise from

Back 18

from prescapular lnn, trapezius mm

Front 19

Where is the thoracodorsal flap used, how are the vessels oriented

Back 19

lesions on elbow, axilla. vessels exit caudal to scapula and run parallel to latissimus dorsi

Front 20

Where is the cranial superficial epigastric flap used

Back 20

Manubrium, sternum

Front 21

Where is the caudal superficial epigastric flap used

Back 21

Thigh,medial hind limb, lateral abdomen (rectus abdominus)

Front 22

What are some properties of the caudal superficial epigastric flap

Back 22

Usually incorporates caudal 3-4 mammary glands = relatively hairless, teats present
Can be rotated laterally, caudally, or distally
flap can be pre-stressed if you need a longer flap
when cutting near prepuce be sure not to cut external pudendal a/v

Front 23

Where is the deep circumflex iliac flap used

Back 23

defects around greater trochanter, tuber ischii

Front 24

where is the reverse saphenous conduit used

Back 24

Use skin on inside of tibia, fold down to close defects on tarsus

Front 25

What is a free graft

Back 25

A detached piece of skin from an animal, can be transferred to distant site where flap cannot reach

Front 26

What is a graft lacking, how does it survive

Back 26

Lacks blood supply, initially survives by absorbing nutrients via transected vessels in subdermal plexus REQUIRES GRANULATION BED

Front 27

How does a 'mesh' work

Back 27

Donor skin is meshed to cover larger area and limit fluid accumulation, heals via epithelialization

Front 28

How does a 'punch graft' work

Back 28

Small dots all over wound + strips of porcie submucosa (from intestine, sterilized, has growth factor)

Front 29

What is the first stage of healing when a free graft is placed

Back 29

Plasmatic imbibition - initially survives by cut vessels and lymphatics absorbing fibrinogen-free, serum-like fluid from graft bed

Front 30

What is the second stage of healing when a free graft is placed

Back 30

Inosculation - vascular anastomosis (3-5 d post graft) - vessels of granulation bed start anastomosing to cut vessels in skin

Front 31

What is the final stage of healing when a free graft is placed

Back 31

Ingrowth of vessels - capillary buds grow into graft space, or into tissue space

Front 32

What are some considerations when choosing a free graft donor location

Back 32

Site with excess skin, similar hair growth

Front 33

What are two methods of harvesting free graft skin

Back 33

At the level of the sub-dermal plexus (full-thickness) with scalpel blade
Superficially with dermatome (split thickness) using electric knife to shave superficial skin off, above hair follicles - donor site doesn't require closure (horses)

Front 34

What should be done to prep the free graft tissue

Back 34

Remove all SQ fat and fascia - Moroccan leather appearance

Front 35

What is a musculocutaneous flap

Back 35

Muscle combined with overlying skin - thicker flap to prevent wound hernias; non-innervated muscle will atrophy

Front 36

What is a microvascular free graft

Back 36

Take a/v, reattach to a/v somewhere else (sideholes in new vessel)
Mot tissues that will survive as axial pattern flap will also survive if vessels are transected and reanastomosed at a distant site
requires microscope

Front 37

What are the two ways to anastomose vessels

Back 37

End-end anastomosis - clamping off, transect, bring together
Side anastomosis - feed one vessel into side of another vessel

Front 38

How is a graft bandaged

Back 38

Suture graft to overlap wound edges, cover with nonadherent dressing, do not remove/disturb for 3 days

Front 39

What are 3 things that will kill a free graft

Back 39

Motion (bandage +/- splint)
Infection (put on abx)
Hematoma (mesh/bandage-fluid accumulation)
All result in discontinuity between graft and bed (starvation)

Front 40

Why does all muscle and fat have to be removed from graft

Back 40

Anything blocking capillary absorption will result in failure

Front 41

What are the axial pattern flaps from cranial to caudal

Back 41

Superficial temporal, Caudal auricular, *Omocervical (trapezius), *Thoracodorsal (latissimus dorsi), Cranial Superficial Epigastric, *Deep Circumflex Iliac, Caudal Superficial epigastric (rectus abdominus), *Reverse saphenous conduit
* = most used
() = underlying muscle can be used