Soft Tissue Surgery: Reconstructive Surgery Flashcards
What instruments are commonly and sometimes required for skin reconstruction?
- Mayo or metzembaum scissors- sharp/blunt dissection of subcut
- Needle holders- mayo-hegar olsen-hedar
- Fine tissue forceps- adsone
Extra
* Skin hooks
* Sterile marker pens
* Ophthalmic instuments
What are the aims of skin reconstruction?
- Square skin edges- not angled
- Accurate tissue apposition- optimial healing
- Slight eversion of the wound edges- appose the dermis
What are halsteads principles?
- Gentle tissue handling
- Meticulous haemostasis
- Preservation of blood supply
- Strict asepsis
- Minimal tension
- Accurate tissue apposition
- Obliteration of dead space
How can skin tension be reduced for appositional sutures?
- Tension-relieving technique
- Appopriate positioning- realsing leg ties
What is undermining and advancing skin?
- Sharp or blunt trauma of subcut
- Avoid injury to subdermal plexus
- Preserve direct cutaneous arteries- undermine panniculus muscle
- Neck, trunk and abdomen
Panniculus muscle- skin twitch
Describe the process of walking sutures
- Absorbable 2-3 metric sutures between dermis and subcut fascia
- When tightened suture pulls skin towards the centre of the wound onto fascia
What are the following tension-relieving suture patterns?
A. Alternating wide and narrow
B. vertical matress
C. horizontal matress
D. far-near-near far
E. far-far-near,near
- What is the function of alternating wide and narrow simple interupted sutures
- What can occur if mattress sutures are poorly placed
- When should tension relieving sutures be removed?
- Relieve minor tension
- Ishaemic skin necrosis
- 3-4 days- leave appositional
What is the function of far-near sutures?
Provide simultaneous tension relief (outer loop) and apposition (inner loop)
- When are relaxing/releasing incisions useful?
- How is the incision closed?
- When the primary defect overlies a vital structure
- Primary or secondary intention
What is multiplle punctate relacing incisions?
Rows of staggered stab incisions on either side of the wound and progressively tighten a preplaced suture
What is a Z and V-Y plasty?
Z- plasty
* Involves making triangular flaps of skin and transposing them to relieve tension
V-Y plasty
* a V-shaped invision created perpendicular to the wound- Y- relieves tension over a relatively limited area
What does a fusiform incision cause?
How can they be dealt with?
Dog ear- Wound sides with different lengths
Suturing the wound spacing sutures further apart on longer side (A)
Suturing the wound by starting halfway
How are triangular and square defects closed?
Start at corners and proceed to centre
Or use transposition or advancement flap
How are Chevron-shaped (V) and circular defects sutured?
Chevron
* close in the shape of a y
* placed first in the stem
Circular
* Convert to linear with fusiform defect then 3 point closure
* Create flaps
What is a skin flap?
Pedicle graft
Flaps are sections of skin with an intact vascular supply that are moved close to wounds
How are flaps planned?
- Use donor sites with ample skin and without excessive tension or movement
- Apporopriate flap for the shape of the wound
- Avoid narrowing the pedicle
- Undermine below panniculus
- Use fine suture material with initial tacking sutures
- Ensure recipient bed is either a fresh or surfical wound
What is a subdermal plexus flap?
What are the different types?
Flaps with blood supplies from the subdermal plexus and attenuated branches of distand direct cutaneous arteries
* Rotation flaps- triangular defects
* Transpositional flaps- rectangular rotated into place over a wound
* Interpolation flaps: similar to transpositinal- do not share common border with wound
* Advancement flaps- unipedicle or bipedicle that use elasticity of skin
- What are axial pattern flaps
- What is the difference between free and peninsular flaps?
- Flaps incorporating a specific, large, direct cutaneous artery and vein
- Free no attachment- peninsular attachment at the donor bed
Why do flaps fail?
- Arterial and/or venous occlusion- thrombi, torsion, stretching
- Elevated interstitial pressure due to excessuve tension causing reduced circulation and necrosis
- Pressure on the flap from underlying haematomas/seromas or tight dressings
- Infection
How can flap health be assessed subjectively and objectively?
Subjectively
* Colour- unreliable
* Temperature- same as surrounding skin
* Sensation- unreliable
* Hair growth- only if flap viable
Objectively
* Flurescin dye flurescence- non-flurorescent areas often dehisce
How can a failing flap be salvaged?
- Apply ointments- prevent desiccation
- Debride nonviable tissue
- Open wound managment followed by secondary closure or development of a second flap
What are free skin grafts?
How do they survive?
- Segments of skin completely deteched from the donor site
- Absorb tissue fluid for 48 hours
- Then develop a new blood supply
What are the pros and cons of full and split thickness grafts?
Full thickness
* durable
* good hair growth
* good survival if meshed
Spit
* more viable
* less duable
* not in cats
What are passive drains?
- Rely on gravity and capillary action
- Efficiency proportional to their surface area
- Exit through seperate stab wound- distal wound
- Inguinal/axillary- proximal end through second incision to avoid emphysma
What are active drains?
- Apply negative pressure
- At least every 6 hours
What layer would you undermine if you are freeing skin around a wonud on the flank?
Panniculus muscle
What is the maximum length-width ratio for an unipedicile subdermal plexus flap?
3:1
blood supply not adequate above this
