flaps and grafts - skinner

what are flaps used for?

to fill large defects

what are the options for flaps?

• skin

• mucosa

• muscle

• composite

when creating a flap, what will you inevitably do?

cut off some blood supply to the flap, making the tip slightly ischemic

what occurs at the base of the flap to blood vessels?

those vessels in line with the flap will become engorged to supply the area

what are the dimensional limitations of creating a skin flap?

the length should not be 2x greater than the width

how can you make a flap longer than 2x the width?

by making a delayed flap that is where you cut the lengths (2 parallel incisions) you want but wait to cut the width part

what is an axial pattern skin graph?

a flap in line with robust blood supply that can help to create a large flap with better chances of success

advancement flap

skin right next to defect is lifted and pulled over into defect

H-plasty flap

taking flaps from both sides of a wound and advancing them into wound to join up

appears as a “H” in the end

rotational flap

cutting a curved flap that is rotated into wound. Is helpful for smaller areas and can look better for cosmetic outcomes

transposition skin

a perpendicular flap that is pivoted over into the defect, the pivot point anchors it that can limit how much the flap can move

better for getting more skin compare to rotational

flank fold

using the excess skin at the flank and swinging up

what are the axial pattern flap locations?

what are the adverse reactions seen with flaps?

• necrosis

• dehiscence

• infection

• swelling

• seroma

do complication occur more with cats or dogs with skin flaps?

dogs

how would it appear for a muscle flap to fill in a thorax body wall defect?

buccal transposition flap

what are skin grafts?

• no blood supply

• reliant on new vessels

• skin only with no SQ tissue at all

what are the types of grafts based on?

how thick the skin is that is used for graft

what are the 2 versions of grafts?

• split thickness → one or multiple layers of skin

• full thickness → contains all layers of skin

what tissue is best to put a graft on?

muscle or granulation tissue

plasmatic imbibiton

graft drinks up wound fluid → may turn red or purple

fibrinous adherence

start of graft sticking to underlying tissue

inosculation

vessels within the graft align with vessels of underlying tissue and they merge

vascular ingrowth

occurs from all directions into the graft

fibrous adherence

macrophages recruit fibroblast to make further connection stronger

what aspects of the graft healing into the area determine graft viability?

• plasmatic imbibition

• inosculation

• vascular ingrowth

what aspects of the graft healing into the area determine graft adhesion?

fibrinous adherence

fibrous adherence

what are the types of grafts?

• sheet

• mesh

• strip

• stamp

• punch

sheet graft

mesh graft

strip graft

stamp graft

punch graft

how do we manage grafts after placement?

• needs to be covered

  • bandage

  • splint

  • non-adherent dressing

• negative pressure wound therapy

  • versatile

  • improved survival

what is the main things to help grafts take?

maintain contact and make immobile

what causes necrosis/graft failure?

• movement

• infection

• hematoma

• seroma

• inadequate fat removal

what are the success rate in grafts in cats and dogs?

• dogs = 38-100%

• cats = 77%

flaps vs grafts

flaps

• vascular supply

• better cosmesis

• range of functions

• limited post-op care

grafts

• no vascular supply

• may have sparse hair

• requires immobilization

• involved post-op care