Tobias 78/ Local Or Subdermal Plexus Flaps/ Slatter 23

Front 1

T or F
subq pedicle grafts have no practical use in dogs

Back 1

true

Front 2

list 3 types of flap classification

Back 2

a.circulation
b.compound or composite
c.location in relation to recipient bed

Front 3

what is the subdermal plexus fed by in dogs and cats

Back 3

terminal branches of direct cutaneous arteries
both of which are associated with panniculus layer

Front 4

what is an axial pattern ?

Back 4

a pedicle graft that incorporates a direct cutaneous artery and vein

Front 5

what is a compound flap?

Back 5

incorporates skin with other tissues including muscle, fat, and cartilage

Front 6

what are myocutaneous grafts most useful for?

Back 6

closure of thoracic and abdominal wall defects

Front 7

name the two basic types of local flaps?

Back 7

rotating flaps

advancement flaps

Front 8

true or false
increasing the width of a pedicle graft increases its total surviving length

Back 8

false

Front 9

what is delay phenomenon?

Back 9

method used to augment survival and improve circulation of a flap

staged flap development
flaps may be trained to rely on their pedicle by gradually cutting of other blood supply

-incison and suture of of proposed flap borders
-partial division of a pedicle of a flap
-temporary occlusion of one pedicle of a bipedicle flap
-tissue expansion

Front 10

according to hoffmeister;s studies, circulatory efficiency after initial flap elevation can decline when?

Back 10

immediately or during period of 3 to 7 days

Front 11

do tissue expanders exert a delay effect on the overlying skin?

Back 11

yes

Front 12

what should you do if there is chronic GT present in the recipient bed?

Back 12

chronic GT should be excised. A healthy bed will appear in 3-5 days

Front 13

what type of flap is commonly used for closure of triangular defects?

Back 13

rotation flap

Front 14

name the differenct types of local flaps?

Back 14

1. rotation flap
2. transposition flap
3. interpolation flap
4. skinfold or pedicle flap
5. advancement flap (single and bipedicle)

Front 15

how often are direct pedicle flaps divided?

Back 15

10-14 days after initial transfer, in stages. 1/2 to 1/3 every 2-3 days to avoid ischemia

Front 16

why are flaps frequently thicker than surrounding skin after transfer?

Back 16

inflammation and fibrous CT deposition

Front 17

how much should a tube flap be increased to compensate for flap shrinkage?

Back 17

25% in length and width

Front 18

list 3 techniques used to move tube flaps by migration

Back 18

a. caterpilling
b. waltzing
c. tumbling

Front 19

lines of tension

Back 19

Front 20

what are subdermal plexus flaps?

Back 20

full thickness "tongues of skin" usually detached along 3 or 4 borders

tradiltionally include skin and sq

relay on collateral circulation to sq (deep) plexus

Front 21

width of hairy skin?

Back 21

0.5-5mm

Front 22

what vessels are composite flaps based on

Back 22

subdermal plexus or direct cutaneous artery

Front 23

what happens to perfusion with elevation of single and bipedicle flaps

Back 23

drops to 10% (single)
40% (bipedicle)

in delayed flaps circulation rises to 120% and 150% at 3 weeks

re-elevation at 3 weeks perfusion is 90% normal:
major advantage of delayed flaps

Front 24

what are the major factors contributing to the delay phenomenon

Back 24

changes in sympathetic tone
dilation of choke vessels
changes in tissue metabolism
neovascularization

Front 25

what happens to vasculature during delay?

what are choke vessels?

Back 25

initially adrenergic tone causes vasocontriction, then NE depletion leads to vasodilation, neovascularization occurs, vessels run parallel to long axis of the flap.

choke vessels, the vessels that link adjacent territories increase in size and number.

Front 26

how long is required for optimal vascular delay?

Back 26

at least 2 weeks

Front 27

what types of flaps benfeit from delay?

Back 27

ischemic flaps

Front 28

what is pavletics approach to tube flaps?

Back 28

total 3 week delay
at 18d, half of the pedicle is divided, remainder is severed 3 days later

Front 29

how should you prepare the recipient site prior to flap placement?

Back 29

-make sure its free of infection or debris, necrotic debris
-granulation tissue should be well vascularized
-dense mature CT should be debrided for vasularity
-margins of chronic wounds should be excised to remove thin layers of epitheliium

Front 30

how long should flap be?

Back 30

as long or longer than wound

a relaxing incision should be 1.5x as long

Front 31

should a flap be wider at its base or its tip?

Back 31

base!
must not be too thin
wider is better: increases chance that cutaneous artery may be included at its base

Front 32

what are the pros and cons of including underlying panniculus musculature in subdermal flap?

Back 32

not including it:
reduces metabolic requirements of the flap
reduces demands on the subdermal plexus

often the underlying musculature is too close to separate the skin from it

most commonly "composite" flaps include underlying musculature, oral mucosa, or both

Front 33

what are the classes of skin flaps when classified by the way they are moved?

Back 33

advancement flaps: shift skin without rotation

rotating flaps: include rotation, transposition, and interpolation flaps.
they pivot around a point central to their base

Front 34

what is a rotation flap?

Back 34

semicircular, cover a triangular defect along one border

Front 35

what is a transposition flap

Back 35

shares a common border with the defect, however , the flap is rotated across intact skin to reach an adjacent defect. bring in new skin to the defect, so are more versatile than advancement flaps

Front 36

what is an interpolation flap

Back 36

lacks a common border with the recipient bed. must be tubed or incorporated into a "bridging incision" betwn the recipient and donor beds.

Front 37

what is the difference between bipedicle and single pedicle flaps

Back 37

single pedicle: two incisions perpendicular to the wound

bipedicle: incision parallel to the wound

Front 38

single pedicle

Back 38

Front 39

bipedicle flap

Back 39

Front 40

guidelines for bipedicle flap length/width

Back 40

width of flap should be roughly width of the wound
total length should be no more than twice the width of the flap base

Front 41

how do you construct a rotation flap?

Back 41

curved incision is begun at a point adjacent to the shortest side of the triangular wound.

incision is gradually lengthened until it is of sufficient length

bilateral rotation flaps can be used to cover rectangular defects

Front 42

guidelines for length and width of transposition flaps

Back 42

as wide as the defect
length = distance betwn pivot point of the flap and the most distant point of the defect

Front 43

name some common composite flaps

Back 43

myocutaneous axial pattern flaps like lattisimus dorsi flap

mucocutaneous flaps like labial advancement flap, lip to lid flap for lower eyelid

Front 44

transposition flap pic

Back 44

Front 45

elbow fold flap

Back 45

preservation of 1 of 4 attachments preserves blood supply
if lateral thoracic artery is included, its actually an axial pattern flap

Front 46

flank fold flap pic.

Back 46

Front 47

name 5 examples of subdermal plexus flaps

Back 47

skin fold flaps
scrotal flap
peripreputial flap
phalangeal fillet
labial flaps
lip to lid flap

Front 48

describe the phalangeal fillet

Back 48

skin over phalanx is incised to produce flap, digit is amputated so that skin can be rotated to deal with metatarsal/metacarpal pad.

Front 49

important vessels involved in labial flaps

Back 49

inferior and superior labial arteries
angularis oris

Front 50

what is a lip to lid flap. what vessel is important

Back 50

angularis oris a+v
uses the junction of the caudal lip skin and attched labial mucosa to replace the lower eyelid

Front 51

how are defects of the lateral lid margin best addressed?

Back 51

by local rotation flap from temporal region

Front 52

major comps of subdermal plexus flaps?

Back 52

infection
necrosis
dehiscence
devascularization
seroma


without adherence to underlying sq:more dead space, tension concentrates around edges. suture pull through, relaice completely of subdermal plexus cuz no angiogenesis from deeper tissues.

Front 53

what is the morbididty of flap procedures post radiation therapy?

Back 53

dehiscence: 62%
flap necrosis: 35%
infection: 27%
risk os highest when radiation performed BEFORE flap because damage to local fibroblasts and vessels

Front 54

what happens to devitalized skin?

Back 54

either liquefactive necrosis or eschar
eshcar ay not seperate from underlying tissue for up to 4 weeks
necrotic skin should be debrided asap

Front 55

what does hyperbaric O2 therapy do for flaps?

Back 55

improves survival by presenting tissue with hyperoxygenated blood that stimulates fibroblasts and enhances tissue revascularization

a review of small animals studies showed small but consistent improvement with hyperbaric treatment

Front 56

what are the two main direct distant flaps?

Back 56

single pedicle flap (hinge flap)
bipedicle flap (pouch flap)

flap is developed from lateral thoracic or abdominal skin, and sutured to limb defect

donor bed is managed as an open wound until the skin has healed to the recipient bed and limb can be cut down

they are suprisingly successful but incredibly time consuming and expensive, so generally axial pattern flaps are preferred.

Front 57

what is a indirect/delayed tube flap and when is it used?
what are the guidelines regarding size in development?

Back 57

used to transfer skin to a distant site when there is no immediate need to cover an area

two parallel incisions are made in mobile ski. the flap is rolled into a tube and ends are sutured together. the underliying defect is undermined and closed primarily. 3 weeks later one end of the tube is severed and advaced into recipient bed. 3 weeks later other end os severed and advanced

length and width should be at least 25% greater than that needed for recipient bed to account for flap shrinkage

axial pattern flaps have basically replaced the need for these

Front 58

how are tubed flaps moved in small animals

Back 58

caterpillaring
waltzing
tumbling