8 skin flaps grafts wound healing

Question 1

What is an axial pattern flap?

Answer 1

An area of skin supplied by a direct cutaneous artery and vein.

Includes island axial pattern flap and subdermal plexus flap.

Question 2

What is an island axial pattern flap?

Answer 2

A flap that’s not connected to the donor site by skin, with the skin incised on all edges, rotating on the direct cutaneous artery and vein.

Question 3

What is a subdermal plexus flap?

Answer 3

Flaps elevated without inclusion of a direct cutaneous artery and vein.

Question 4

List ways to maximize survival of axial pattern flaps (12).

Answer 4

1. • Pre-stretching prior to surgery
2. • Patient preparation (preoperative vs. perioperative antibiotics)
3. • Culture recipient site after debriding
4. • Use ultrasound to check artery location
5. • Measure flap size accurately
6. • Care with patient positioning
7. • Prep recipient bed cleanly
8. • Avoid excessive twisting (not more than 180 degrees)
9. • Use peripheral tacking sutures
10. • Close with simple interrupted pattern
11. • Consider a drain for larger flaps
12. • Gentle tissue handling

Question 5

What are postoperative measures to reduce tension, swelling, and inflammation? (6)

Answer 5

1. • NSAIDs
2. • Cool packs for first 36-72 hours
3. • Warm packs for 3-5 days
4. • Bandage (not too tight)
5. • Use active drain
6. • E collar or other protective measures

Question 6

Name four axial pattern flaps and their clinical scenarios.

Answer 6

• Angularis Oris – facial, palatal, nasal defects
• Superficial Temporal – maxillofacial, eyelid
• Caudal auricular – for large eyelid tumors
• Thoracodorsal – thoracic, shoulder, forelimb defects

Question 7

What are the 5 stages of acceptance of full thickness free skin grafts?

Answer 7

1. Adherence
2. Plasmatic imbibition
3. Inosculation
4. Vascular ingrowth
5. Remodelling

Question 8

What are factors that influence the take of skin grafts? (7)

Answer 8

1. the health of the recipient wound bed (vascularity)
2. infection at the graft or donor site
3. presence of hematoma or seroma
4. patient’s overall health (cushings, diabetes)
5. wound bed preparation
6. surgical technique/gentle tissue handling/suture patterns used
7. The type of graft used (axial pattern vs. subdermal plexus)

essentially, any factor that disrupts blood supply to the graft or causes excessive movement or stress on the newly placed skin can lead to graft failure.

Question 9

Three techniques to eliminate dead space includes _______. (3)

Answer 9

1. Adequate subcutaneous sutures
2. Tacking sutures
3. Negative pressure/active drains

Question 10

What is the delay phenomenon in relation to axial pattern flaps?

Answer 10

It increases flap survival through staged procedures that restrict blood supply gradually, allowing for better revascularization.

Question 11

What anatomical features allow for axial pattern flaps in canine and feline skin?

Answer 11

• Direct cutaneous vessels run parallel to skin in dogs and cats
• Greater density of collateral subcutaneous vessels in dogs
• Thinner dog skin compared to human skin

Question 12

What are four patient factors that affect cutaneous wound healing?

Answer 12

• Species differences (cats vs. dogs)
• Breed (tight skin prone to complications)
• Body condition (increased SC fat challenging)
• Age (geriatric patients have less perfusion)

Question 13

What are 5 intrinsic local wound factors affecting wound healing? (5)

Answer 13

1. Blood supply
2. Granulation tissue health
3. Bacterial load (contaminated wounds require different management)
4. Structural damage (debride devitalized tissue)
5. Periwound status (oedema and inflammation)

Question 14

What is the expected time frame for the adherence phase of free skin grafts?

Answer 14

1st phase:: First 8 hours
2nd phase: 72hrs

Question 15

What are the phases of integration for free skin grafts? (5)

Answer 15

1. Adherence
2. Plasmatic imbibition
3. Inosculation
4. Vascular ingrowth
5. Reinnervation

Question 16

True or False: Dogs have a greater density of collateral subcutaneous vessels compared to cats.

Answer 16

True

Question 17

What is the significance of using Halsted’s principles during grafting?

Answer 17

They emphasize gentle tissue handling and infection control to improve graft survival.

Question 18

What happens during plasmatic imbibition phase?

Answer 18

Graft blood vessels vasospasm, expelling blood, then dilate to receive serum-like fluid and cells.
The skin graft passively absorbs oxygen and nutrients from the wound bed via capillary action. During this phase, the skin graft is ischemic and survives on diffusion alone until reestablishing graft vasculature. The graft is pale/white during this time. Split-thickness skin grafts can tolerate up to 4 days of ischemia.

Question 19

What are dog ears?

Answer 19

Triangular skin protrusions that can affect local structures like the eye but are mostly cosmetically displeasing.

If less than 8mm, they will regress themselves; larger ones should be resected

Question 20

What is the effect of step defects on healing?

Answer 20

Epithelialisation is delayed.

Question 21

What are tension relieving suture patterns? (4)

Answer 21

1. Strong subcutaneous sutures
2. Stent or bolster sutures
3. Walking sutures
4. Horizontal mattress sutures
5. Vertical mattress sutures

Question 22

What is the purpose of walking sutures?

Answer 22

To create staggered rows of interrupted intradermal sutures that are secured to underlying fascia with directional tension towards closure.

Question 23

True or False: Horizontal mattress sutures may compromise blood supply to the wound edge.

Answer 23

True.

Question 24

What is the effect of vertical mattress sutures on blood supply? (2)

Answer 24

Vertical mattresses do not compromise blood supply but can create eversion.

Question 25

What are the types of skin stretching techniques? (5)

Answer 25

1. Pretensioning sutures 1. Posttensioning sutures 1. Presuturing 1. Intraoperative skin stretching 1. Chronic skin expansion

Question 26

What is a VY plasty?

Answer 26

A flap technique that uses a triangular cut to advance tissue and create a Y incision

Question 27

What is the purpose of Z plasty?

Answer 27

To change the direction of tension and make more skin available. Can increase length of scar by 50-75%

Question 28

Fill in the blank: The skin has ______ basic layers.

Answer 28

[two] (epidermis and dermis). ## Footnote Hypodermis includes SC and adipose/connective tissue

Question 29

What are the vascular supply divisions in the skin? (3)

Answer 29

1. Subpapillary plexus (superficial) 1. Cutaneous plexus (middle) 1. Subcutaneous plexus (deep/subdermal)

Question 30

How strong is a surgical wound after 14 days?

Answer 30

5-10% as strong as normal skin.

Question 31

What is the wound healing difference between cats and dogs?

Answer 31

Cats have lower cutaneous perfusion and wound breaking strength than dogs at 1 week post-op, with healing more by contraction.

Question 32

List factors that influence wound healing.

Answer 32

1. Tension 1. Pressure 1. Motion 1. Self mutilation 1. Patient health (uremia, glucocorticoid excess, etc.) 2. Infection

Question 33

How does malnutrition affect wound healing? (4)

Answer 33

1. Delayed neovascularisation 1. Decreased collagen synthesis 1. Prolonged inflammation, 1. Decreased immune function.

Question 34

What is the typical healing strength of skin at 3-4 weeks post-surgery?

Answer 34

25% as strong as normal skin.

Question 35

What is the role of tension lines in wound closure?

Answer 35

Wounds should generally be made parallel to tension lines to reduce tension during healing.

Question 36

Taking care of an active drain: (2) to avoid/control infection

Answer 36

2. Cover drain exit sites with sterile dressing 1. Consider culturing drain fluid when removed

Question 37

Tension reducing suture patterns (7)

Answer 37

1. SC sutures 2. bolster/stent sutures 3. Walking sutures 4. Far, near, near, Far 5. Far, far, near near 6. horizontal mattress 7. vertical mattress

Question 38

What type of defects does Angularis Oris address?

Answer 38

Facial, palatal, nasal defects ## Footnote Angularis Oris is involved in reconstructive procedures for facial and palatial areas.

Question 39

What is the application of the Caudal auricular axial pattern flap?

Answer 39

For dorsal/lateral large eyelid tumours or tumours adjacent to that area ## Footnote This flap can also be used for reconstructions in the neck, fascial, dorsal head, and ear.

Question 40

Which anatomical areas does the Thoracodorsal flap cover?

Answer 40

Thoracic, shoulder, forelimb, axillary defects

Question 41

What defects are associated with the Superficial brachial flap?

Answer 41

Antebrachial, elbow defects ## Footnote This flap is specifically designed for the forelimb area.

Question 42

What areas does the Dorsal deep circumflex iliac flap target?

Answer 42

Flank same side, lateral lumbar, pelvic lateromedial thigh, greater trochanter

Question 43

The Ventral deep circumflex iliac flap is used for which defects?

Answer 43

Lateral abdominal wall, pelvic, sacral defects ## Footnote This flap is important for reconstructive procedures in the lower abdominal area.

Question 44

What defects does the Cranial superficial epigastric flap address?

Answer 44

Sternal defects

Question 45

What types of defects can the Caudal superficial epigastric flap repair?

Answer 45

Inguinal, preputial, perineal, stifle defects

Question 46

What is the focus area of the Lateral Caudal flap?

Answer 46

Lateral perineal, caudodorsal pelvic defects

Question 47

The Lateral Genicular axial pattern flap is used for repairing defects in which specific areas?

Answer 47

Medial or lateral aspects of crus (between stifle and tibiotarsal joint)

Question 48

Fill in the blank: The Superficial Temporal flap is used for _______.

Answer 48

maxillofacial, eyelid area ## Footnote This flap is crucial for addressing defects in the facial and eyelid areas.

Question 49

How many branches are associated with the Cervical Cutaneous branch Omocervical?

Answer 49

2

Question 50

How many branches does the Dorsal deep circumflex iliac flap have?

Answer 50

6 ## Footnote This number indicates its complexity and range.

Question 51

True or False: The Caudal superficial epigastric flap is primarily used for upper body defects.

Answer 51

False ## Footnote It is used for lower body defects.

Question 52

3 advantages of axial pattern flaps over other types of wound closure

Answer 52

1. more robust blood supply; flaps can be 2 x size of subdermal plexus 2. More reliable survival 3. Can be placed over bone, doesnt need granulation tissue/2 stages

Question 53

Reasons Axial pattern flaps can necrose

Answer 53

1. twisting around more than 180 degrees 1. excessive undermining 1. previous tissue trauma 1. damage to primary axial artery and vein during harvesting 1. excessive wound tension 1. hematoma/seroma formation 1. skin flap too long

Question 54

Whats another name for Delay Phenomenon

Answer 54

Ischemic preconditioning

Question 55

how long do you leave pre incised skin flap prior to grafting if using preconditioning ischemic technique

Answer 55

3 weeks.

Question 56

how does uremia affect wound healing (3)

Answer 56

1. causes chronic inflammation 2. inhibits fibroblasts activity 3. reduces collagen production

Question 57

how strong is wound 14 days after surgery

Answer 57

5-10% as strong as normal skin

Question 58

what factors affect healing of wounds

Answer 58

tension pressure motion self mutilation patient health infection

Question 59

Time frame Adherance

Answer 59

1-3 days (2 phases)

Question 60

Time frame plasma imbibition (skin grafting)

Answer 60

1-3 days, peaks at 48-72hrs

Question 61

what is Inosculation and Time frame (skin grafting)

Answer 61

The graft's cut vessels connect with the recipient's capillary beds. This process usually happens about 48 hours after the graft is placed. The graft turns pink when inosculation occurs. 1-3 days, reduced perfusion by 5-6days.

Question 62

what happens during 4th phase skin grafting, name, timing

Answer 62

Vascular ingrowth: vessels grow from the recipient bed into the skin graft, and may grow into the dermis of graft , begins within 48hrs, peak vascular growth 5-7days,

Question 63

Describe deep ventral circumflex iliac axial pattern flap

Answer 63

base of flap is ventral extent cranial aspect wing ilium. Caudal incision begins that level, midway between wing of ilium and greater trochanter, and extends ventrally. Distance between caudal incision and cranial edge wing ilium measured; cranial incision parallel to caudal incision/cranial border femoral shaft and equidistant to iliac wing. Can extend ventrally to the level of proximal patella. Flaps elevated beneath the cutaneous trunci muscle.

Question 64

type of comorbidities that reduce chance of skin flap healing (6)

Answer 64

Infection anemia anorexia cachexia Uremia chronic inflammatory dz

Question 65

post operative factors that impair skin graft healing

Answer 65

1. seroma/hematoma formation (drains/bandage) 2. infection (culture + Abs) 3. excessive movement (splints/bandages) 4. self trauma (E collars, bandages)

Question 66

how long to bandage a skin graft for

Answer 66

24-48hrs

Question 67

what are Halsteds principles (7)

Answer 67

1. Handle tissues with care and avoid damaging them 1. Control bleeding effectively 1. Maintain the blood supply to the surgical site 1. Maintain strict asepsis, or cleanliness, throughout the procedure 1. Avoid excessive tension on tissues 1. Position tissues accurately 1. Eliminate dead space, or areas where tissue has been removed