Transcript WOUND HEALING AFTER SURGERY0 0

WOUND HEALING AFTER
SURGERY
DR . BINDU MOHANDAS
S- 3 UNIT
Definition:
Wound healing is a mechanism where
by the body attempts to restore the
integrity of the injured part.
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The process of healing involves two distinct
process
1 . REPAIR
2 . REGENERATION
REPAIR
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When healing takes place by proliferation of
connective tissue elements.
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It results in fibrosis and scarring
REGENERATION
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When healing takes place by proliferation of
parenchyml cells
It usually results in complete restoration of
original tissues
Tissues with high proliferative capacity can
regenerate after injury as long as the stem cells
of these tissues are not destroyed
NORMAL WOUND
HEALING
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Takes place in 3 phases
1. Inflammatory phase
2. Proliferative phase
3. Remodelling phase
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Inflammatory phase
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Begins immediately after wounding
Lasts for 2-3 days.
PMN cells & macrophages are attracted
towards the fibrin clot.
Proliferative phase
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lasts from 3rd day to 3rd week
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Consist mainly of fibroblast activity with
production of collagen & ground substance,
angiogenesis & reepithelisation of wound
surface.
Remodelling phase
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Maturation of collagen
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Wound strengthening occurs
Mechanism of
wound closure &
healing
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Skin wounds are classically described to heal
by
A) by primary intention
B) by secondary intention
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This is based on the nature of the wound rather
than the healing process.
Healing by first intention
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Wound with opposed edges.
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Healing of a clean, uninfected surgical incision
approximated by surgical sutures.
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Also called as healing by primary union.
Steps:1.
2.
Within 24 hrs – neutrophils appears at the
margins of the incision, moving towards the
fibrin clot.
24-48 hrs – spurs of epithelial cells move from
the wound edges along the cut margins of the
dermis. Depositing the basement membrane
components.
By 3rd day
– neutrophils are replaced by
macrophages
– granulation tissue invades the incision
and collagen fibres appears near the margins of the
incision
– granulation issue invades the incision
and collagen fibres appears near the margins of the
incision
– epithelial cell proliferation thickens the
epidermal layer.
By day 5
- incisional space is filled with granulation
tissue, with maximal neovascularization
- collagen fibrils are abundant & bridges the
incision.
- epidermis recovers its normal thickness
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By 2nd week – continued accumulation of
collagen and proliferation of fibroblasts within
the incisional scar, accompained by regression
of vascular channels.
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By end of 1st month- the scar is made up of
cellular connective tissue devoid of
inflammatory infiltrate, the decimal appendages
are permanently lost in the line of incision.
Tensile strength of the wound increases.
Healing by secondary intention
(Secondary union)
-Occurs
in wounds with separated edges.
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Inflammatory reaction is more intense.
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Large amount of granulation tissue are formed
-wound
contraction-reduces the size of the wound
Healing takes place from the base to upwards as
well as from the margin inwards
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Delayed primary intention (teritiary intention)
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Wound is initially left open
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Edges are later opposed when healing
conditions are favourable
Normal Healing in
Specific Tissues
1) Bone
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Periosteal and endosteal proliferation leads to
callous formation
In remodelling phase, cortical structure & the
medullary cavity are restored.
2) Nerve
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Distal to the wound,
Wallerian degeneration
occurs
Proximally the nerve
suffers traumatic
degeneration as far as the
last node of Ranvier
Nerve regeneration is
characterised by profuse
growth of new nerve
fibres which sprout from
the cut proximal end.
3)Muscles
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SKELETAL MUSCLE
- similar to peripheral nerve regeneration
- on injury, cut ends of muscle fibres retract
- the injured site is filled with fibrinous
material, polymorphs & macrophages
SMOOTH MUSCLE
- It has limited regenerative capacity
- In large destructive lesions, smooth muscle is
replaced by permenant scar tissue
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CARDIAC MUSCLE
-Destruction of heart muscle is replaced by
fibrous tissue
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HEALING OF MUCOSAL SURFACE
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Very good regenerative power
- Occurs by proliferation from margins, migration,
multilayering, and differentiation of epithelial
cells
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HEALING OF SOLID EPITHELIAL
ORGANS
- Following gross tissue damage to organs
like kidney, liver & thyroid, the replacement is by
fibrous scar
- But if the basement membrane is intact &
only parenchymal damage is present,
regeneration occurs
MANAGEMENT OF
ACUTE WOUND
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Follow principles of ALTS
Thorough examination of wound site after
copious saline irrigation
Examine the possible structures that are
damaged under analgesia
Assess the movement and sensation
wound exploration and diagnosis
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A bleeding wound should be elevated &
pressure pad is applied
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WOUND DEBRIDEMENT- wound should be
debrided to limit of blood supply, devitalised
tissues must be excised
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Repair of all damaged structures are attempted
Management of Specific
wounds
1. Bites
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As per above
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Antibiotic coverage for
aerobic and anaerobic
orginisms
2. Haematomata
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Release by incision/aspiration
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Surgical exploration is case of calcification
3. Degloving
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Open – ring avulsion
injury with loss of finger
skin
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Closed – rollover injury
4. Compartment Syndrome
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Occurs in closed lower limb
injuries
Characterised by severe pain,
pain on passive movement of
the affected compartment
muscles, distal sensory
disturbance, absence of pulse
distally.
treatment: fasciotomy
5. High pressure injection
injuries
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Occurs in person working with cleaning,
degreasing and painting devices
tissue damage depends on toxicity of substance
and injection pressure
Treatment is surgical with wide exposure,
removal of the toxic substance and through
debridement.
Management of
chronic wounds
1. Leg ulcers
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Treatment of the underlying
cause
A chronic ulcer unresponsive
to treatment should be
biopsied to rule out
neoplastic change
Surgical treatment is required
if non operative treatment
fails
Meshed skin grafts may be
required
2. Pressure sores
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Prevention – good skin care
foam beds
pt. turning at least every 2hrs
Preoperative treatment of pressure sore involves
adequate debridement and the use of vaccum
assisted closure.
Factors that retard wound
healing
1. Local factors
Blood supply
denervation
Local infection
Foreign Body
Hacmatoma
Mechanical stress
Necrotic issue
Protection (dressing)
Surgical techniques
type of tissue
2. Systemic factors
Age
Anemia
Drugs (steroids, cytotokie, medications)
genetic disorders
Hormones
Diabetes
Malignant disease.
Malnutruction
obesity
Systemic infection
temperature
trauma, Hypevolemia
hypoxia
Vit & trace metal
deficiency
COMPLICATIONS OF
WOUND HEALING
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Hypertrophic scar & keloid
Wound dehisense &
ulceration
Contractures
Wound infection
Incisional hernia
Implantation cyst formation
Pigmentation
Neoplasia
Source of information
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Robin’s text book of pathology
Harsh mohan’s text book of pathology
Bailey and love’s book of surgery
Sabiston’s book of surgery
www.pubmed.com
www.google.com