The document discusses wound healing and skin flaps. It covers topics like the different types of wound healing (primary, secondary, tertiary), the stages of wound healing (hemostasis, inflammation, proliferation, remodeling), factors that affect wound healing, and types of skin flaps (local, distant, pedicled, free flaps). It also discusses concepts like angiosomes, perforasomes, and reasons for potential skin flap failure.

1. Dr Grace Vandana
First yr ent pg

2. Wound:
 A wound is defined as a break in the integrity
of the skin epithelium, often accompanied by
concurrent disruption of the underlying dermis

3.  Primary healing ( healing by first intention):
 Secondary healing(healing by second intention)
 Teritary healing

4.  Healing by primary intention involves:
 clean wound edges closed within 24 hours
 surgical incision/laceration
 approximation using sutures, skin glue or steri-
strips
 hairline scar.
 Healing by secondary intention involves:
 large gaping or infected wounds
 epithelial cells grow downwards and across the
wound bed
 contraction and epithelialization occurs
 slower than healing by primary intention and

5.  Healing by tertiary intention
involves:
 contaminated wounds
 wound edges left unopposed for up to 4 days
for phagocytosis to occur
 wound edges then approximated, often loosely.

8.  Haemostasis
 Inflammation
 Proliferation
 Remodelling
 Failure – chronic non healing wounds
 Aberrant – keloid / hypertrophic scar

9.  Four processes, essential to wound healing, are
initiated following these events:
• Clotting cascade
• Complement cascade
• Kinin cascade
• Plasmin generation

11.  Lasts upto 4 days
 2 stages
o Early :1-2 days
 Neutrophils : proteolytic enzymes and free
radical mechanisms
o Late: 2-3 days
 Monocytes (macrophages)
 Phagocytosis and cytokine release causing
proliferation and granulation tissue formation.

12.  Day 3 to week 2
 2 stages : re epithelisation
 granulation tissue formation
o Re epithelisation
 Replication and migration of epidermal cells
 Epiboly :delicate covering over raw area
 Contact inhibition

13.  3 steps : fibroplasia
wound contraction
angiogenesis
 Fibroplasia includes recruitment and proliferation of
fibroblasts
 ECM production
 Fibrous structural proteins Interstitial matrix
 Collagen -glycoproteins
 Elastin -proteoglycan
-glycosaminoglycan

14.  Reduces the size of defect
 Limited contraction – delayed wound closure
 Excessive contraction – contractures
o Angiogenesis :
 Begins after 2-3 days
 Degradation of parent vessel
 Migration of endothelial cells
 Proliferation
 Maturation into capillary tubes
 Factors VEGF,PDGF,FGF

15.  Metalloprotinases – proteolytic collagen
degradation
 Excessive – impaired wound healing
 Hence regulated by tissue inhibitors of
metalloproteinases
 Equilibrium b/w collagen syntesis and
degradation by 21 days after injury
 Only upto 80% of tensile strength of
unwounded skin is regained

17.  A similar process to that of soft tissue, with an
added osteogenic component.
 Important cytokines include: TNF-α and Bone
morphogenic proteins.
 Osteoclasts and macrophages remove wound
debris and gradually granulation tissue is
formed.
 Chondroblasts and osteoblasts create a soft
callus

19.  Age: delayed wound healing with increasing age
 Nutritional status: malnutrition impairs
wound healing
 Chronic disease: diabetes, peripheral vascular
disease and chronic venous insufficiency all
predispose to ulceration and poor wound healing
 Several medications impair wound healing, in
particular: steroids, non-steroidal anti-inflammatory
drugs, cytotoxic agents and immunosuppressants
 Pressure-prone anatomical areas can lead to ulcer
formation
 Infection impairs wound healing.

20.  Nutritional status:
 Several ‘pro-healing’ nutrients have been
identified including:
 arginine, vitamins A and C and zinc.

21. o Diabetes mellitus:
 The effect of increased serum glucose, in diabetic
patients, on wound healing is multifactorial. Some of
these effects include:
 Increased vascular permeability leading to peri-
capillary albumin deposition and impaired diffusion of
oxygen and nutrients
 Inhibition of function of structural and enzymatic
proteins due to non-enzymatic glycolization
 Glycosylated collagen resistance to enzymatic
degradation
 Hence diabetic wounds demonstrate decreased
granulation tissue, decreased collagen, slow wound
maturation and decreased numbers of fibroblasts

22. Wounds can be classified in a number of ways:
Acute vs. Chronic:
(i) acute: thermal wounds,
surgical wounds and
traumatic wounds;
(ii) chronic: diabetic ulcers,
pressure ulcers,
venous ulcers,
arterial ulcers
and mixed ulcers
According to the type of wound tissue:
granulation tissue, epithelial tissue, necrotic tissue
or infected tissue.

23. o Wound assessment involves evaluation of:
 Wound size,
 Edges,
 Location (anatomical site)
 status of wound bed and tissue.

24.  A skin flap is a block of tissue transferred from
the donor site and inserted to the recipient site
while maintaining a continuous attachment to
the body (the pedicle).
 The flap may consist of skin and subcutaneous
fat but could also include mucosa, fascia,
muscle, bone, nerve or combinations thereof.

25.  Free flap refers to autologous tissue transfer
from a distant donor site to reconstruct a defect
after the pedicle has been completely detached.
 Blood supply is reinstated by means of
microsurgical anastomoses of donor artery and
vein(s) to the recipient artery and vein(s).

26.  The term ‘flap’ is alleged to originate from the
dutch flappe, meaning something broad and loose that
hangs and attached only at one side.
 Reconstructive skin flap surgery owes a great deal
to the work of the Indian ayurvedic medical
practice of Nasal reconstruction.
 Sushruta samhita, the classical surgery textbook
written around 600 BC, describes the first cheek
flaps utilized for nose repair.
 The English surgeon Joseph carpue (1764–1840) is
given credit for introducing the Indian forehead
rhinoplasty technique into the english language,

27.  Flaps are divided into two main categories,
o Based on whether the pedicle remains
attached to the donor site or not:
 pedicled
 free flaps
o Based on location:
 local
 distant flaps

32. Based on
method of
movement
Advancement Pivotal
Transposition Rotational

33. Advancement
flap
Transpositional
flap
Rotational flap

34.  Advancement flaps:
 relies on skin elasticity for the closure of
primary defect
 Ex:naso labial V-Y flap

37.  Pivot flaps:
 A pivot flap moves about a fixed pivot point
and can either be a
 Transposition flap where the flap moves
laterally across the pivot point or
 Rotation flap where the flap is rotated around
the pivot point

38.  Used in lateral nasal and cheek defects

40.  Abbe Estlander flap

41.  oral mucosa ,buccinator muscle and facial
artery
 For small defects of oral cavity mucosa of lip
and palate.

43.  Facial artery branches

44.  Based on superficial
temporal artery.

45.  Pedicled mucoperichondial and
mucoperiosteal flap based on nasal septal
artery
 Used in reconstruction of anterior skull base
defects.

46.  Based on perforating internal mammary
arteries.
 Head and neck reconstruction

48.  Pectoral branch of acromiothoracic artery

49.  Angiosomes
 Taylor and palmer coined the term ‘angiosome’ in
order to describe the spatial pattern of blood supply in
various parts of the integument.
 Houseman et al. Describe 13 angiosomes in the head
and neck region mostly supplied from the external
carotid, internal carotid and subclavian arteries.
 All 13 but the lingual, vertebral and ascending
pharyngeal angiosomes contribute to the abundant
subdermal vascular network
 The three angiosomes,
 Vertebral (11),
 Ascending pharyngeal (12)
 And lingual (13), which do not reach the skin surface

50. ANGIOSOMES

51.  In analogy to ‘angiosomes’, Saint-Cyr et al.
recently introduced the term ‘perforasomes’ as
well defined vascular territories nourished by a
single perforator
 Each perforasome carries a multidirectional
flow pattern that is highly variable and
complex. These perforasomes are linked to one
another by both direct and indirect linking
vessels, which themselves are linked by
communicating branches

53.  Perforator flaps designed at a midpoint
between two articulations can be designed in
multiple fashions because of the
multidirectional perforator flow distribution.
 However, perforators located in proximity to
one articulation seem to have unidirectional
flow, i.e. distally located forearm perforators
(wrist joint) course towards the proximal
forearm (elbow joint), and vice versa

54.  Flap viability is initially dependent on its
robust blood supply via the pedicle so that
metabolic demands of the mobilized tissue are
met.
 Multiple anatomical and physiological factors
that hamper adequate perfusion, before the
collateral capillary network develops, can be
detrimental for the flap survival.

55.  Flap survival depends on flow though the
pedicle of the flap

56.  In a small vessel in which vessel diameter
reduces, as does the pressure within the vessel.
 The vessel will collapse at the point elastic
tension in the vessel wall exceeds the
transmural pressure (p).
 This is known as critical closure pressure.

57. o Non linearity:
 limited lengthening of the skin when it is acutely
stretched.
o Anisotropy
 refers to the directional qualities of the skin.
 In most regions of skin, there is tension in every
direction, being greatest along the relaxed skin tension
line (RSTL).
 Hence, an incision placed perpendicular to the RSTL
will result in a wide gaping wound.
o Viscoelasticity
 seems to be the background of the tissue expansion
and serial sections

59.  The most common cause for the flap failure
being failure to recognize a compromised
circulation.
 Vascular occlusion (thrombosis) of one of the
vessels was the primary (4.5% arterial, 6.8%
venous) reason for flap loss, with venous
thrombosis being more common than arterial
occlusion. The majority of flap failures
occurred within the first 36 hours

60.  Extrinsic :
 External compression of the circulation to the
flap is either due to a tight dressing, tension in
the skin wound closure
 The prompt release of thigh bandages,
dressings and removal of wound sutures and
heamatoma drainage may salvage the situation
 Intrinsic :
 Co morbidities like age, systemic diseases
 Vasospasm in the pedicle