WOUND HEALING WOUND HEALING AFTER SURGERYAFTER SURGERY

DR . BINDU MOHANDASDR . BINDU MOHANDAS

S- 3 UNITS- 3 UNIT

Definition:Definition:

Wound healing is a Wound healing is a mechanism where by the mechanism where by the body attempts to restore the body attempts to restore the integrity of the injured part. integrity of the injured part.

The process of healing involves The process of healing involves two distinct processtwo distinct process

1 . REPAIR1 . REPAIR

2 . REGENERATION2 . REGENERATION

REPAIRREPAIR

When healing takes place by When healing takes place by proliferation of connective tissue proliferation of connective tissue elements.elements.

It results in fibrosis and scarringIt results in fibrosis and scarring

REGENERATIONREGENERATION

When healing takes place by When healing takes place by proliferation of parenchyml cellsproliferation of parenchyml cells

It usually results in complete It usually results in complete restoration of original tissuesrestoration of original tissues

Tissues with high proliferative Tissues with high proliferative capacity can regenerate after injury capacity can regenerate after injury as long as the stem cells of these as long as the stem cells of these tissues are not destroyedtissues are not destroyed

NORMAL NORMAL WOUND WOUND

HEALINGHEALING

Takes place in 3 phasesTakes place in 3 phases

1. Inflammatory phase1. Inflammatory phase

2. Proliferative phase2. Proliferative phase

3. Remodelling phase3. Remodelling phase

-

Inflammatory phase Inflammatory phase

- Begins immediately after wounding Begins immediately after wounding - Lasts for 2-3 days.Lasts for 2-3 days.- PMN cells & macrophages are PMN cells & macrophages are

attracted towards the fibrin clot.attracted towards the fibrin clot.

Proliferative phaseProliferative phase

- lasts from 3lasts from 3rdrd day to 3 day to 3rdrd week week

- Consist mainly of fibroblast activity Consist mainly of fibroblast activity with production of collagen & with production of collagen & ground substance, angiogenesis & ground substance, angiogenesis & reepithelisation of wound surfacereepithelisation of wound surface. .

Remodelling phaseRemodelling phase

- Maturation of collagenMaturation of collagen

- Wound strengthening occursWound strengthening occurs

Mechanism of Mechanism of wound closure wound closure

& healing& healing

- Skin wounds are classically described Skin wounds are classically described to heal byto heal by

A) by primary intentionA) by primary intention

B) by secondary B) by secondary intentionintention

- This is based on the nature of the wound This is based on the nature of the wound rather than the healing process.rather than the healing process.

Healing by first intentionHealing by first intention

- Wound with opposed edges.Wound with opposed edges.

- Healing of a clean, uninfected Healing of a clean, uninfected surgical incision approximated by surgical incision approximated by surgical sutures.surgical sutures.

- Also called as healing by primary Also called as healing by primary union.union.

Steps:-Steps:-

1.1. Within 24 hrsWithin 24 hrs – neutrophils – neutrophils appears at the margins of the appears at the margins of the incision, moving towards the fibrin incision, moving towards the fibrin clot.clot.

2.2. 24-48 hrs24-48 hrs – spurs of epithelial cells – spurs of epithelial cells move from the wound edges along move from the wound edges along the cut margins of the dermis. the cut margins of the dermis. Depositing the basement Depositing the basement membrane components.membrane components.

By 3By 3rdrd day day – – neutrophils are replaced neutrophils are replaced

by by macrophages macrophages – – granulation tissue invades granulation tissue invades

the incision and collagen fibres appears the incision and collagen fibres appears near the margins of the incisionnear the margins of the incision

– – granulation issue invades granulation issue invades the incision and collagen fibres appears the incision and collagen fibres appears near the margins of the incisionnear the margins of the incision

– – epithelial cell proliferation epithelial cell proliferation thickens the epidermal layer.thickens the epidermal layer.

By day 5By day 5 - - incisional space is filled with incisional space is filled with granulation tissue, with maximal granulation tissue, with maximal neovascularizationneovascularization

- collagen fibrils are abundant & - collagen fibrils are abundant & bridges the incision.bridges the incision.

- epidermis recovers its normal - epidermis recovers its normal thicknessthickness

By 2By 2ndnd week week – – continued accumulation of continued accumulation of collagen and proliferation of fibroblasts within collagen and proliferation of fibroblasts within the incisional scar, accompained by regression the incisional scar, accompained by regression of vascular channels.of vascular channels.

By end of 1By end of 1stst month month- - the scar is made up of the scar is made up of cellular connective tissue devoid of cellular connective tissue devoid of inflammatory infiltrate, the decimal appendages inflammatory infiltrate, the decimal appendages are permanently lost in the line of incision. are permanently lost in the line of incision. Tensile strength of the wound increases.Tensile strength of the wound increases.

Healing by secondary Healing by secondary intention (Secondary intention (Secondary

union)union)-Occurs in wounds with separated Occurs in wounds with separated edges.edges.

- Inflammatory reaction is more Inflammatory reaction is more intense.intense.

- Large amount of granulation tissue Large amount of granulation tissue are formedare formed

-wound contraction-reduces the size of wound contraction-reduces the size of the woundthe wound

- Healing takes place from the base to Healing takes place from the base to upwards as well as from the margin upwards as well as from the margin inwardsinwards

Delayed primary intention Delayed primary intention (teritiary intention)(teritiary intention)

Wound is initially left openWound is initially left open

Edges are later opposed when Edges are later opposed when healing healing

conditions are favourableconditions are favourable

Normal Healing in Normal Healing in Specific TissuesSpecific Tissues

1) Bone1) Bone

Periosteal and endosteal Periosteal and endosteal proliferation leads to callous proliferation leads to callous formationformation

In remodelling phase, cortical In remodelling phase, cortical structure & the medullary cavity are structure & the medullary cavity are restored. restored.

2) Nerve2) Nerve

Distal to the wound, Distal to the wound, Wallerian degeneration Wallerian degeneration occursoccurs

Proximally the nerve Proximally the nerve suffers traumatic suffers traumatic degeneration as far as degeneration as far as the last node of Ranvierthe last node of Ranvier

Nerve regeneration is Nerve regeneration is characterised by characterised by profuse growth of new profuse growth of new nerve fibres which nerve fibres which sprout from the cut sprout from the cut proximal end.proximal end.

3)Muscles3)Muscles

SKELETAL MUSCLESKELETAL MUSCLE

- similar to peripheral nerve - similar to peripheral nerve regenerationregeneration

- on injury, cut ends of muscle - on injury, cut ends of muscle fibres retractfibres retract

- the injured site is filled with - the injured site is filled with fibrinous material, polymorphs & fibrinous material, polymorphs & macrophagesmacrophages

SMOOTH MUSCLESMOOTH MUSCLE

- It has limited regenerative capacity- It has limited regenerative capacity

- In large destructive lesions, smooth - In large destructive lesions, smooth muscle is replaced by permenant scar muscle is replaced by permenant scar tissuetissue

CARDIAC MUSCLECARDIAC MUSCLE

-Destruction of heart muscle is replaced -Destruction of heart muscle is replaced by fibrous tissueby fibrous tissue

HEALING OF MUCOSAL HEALING OF MUCOSAL SURFACESURFACE

- Very good regenerative powerVery good regenerative power

- Occurs by proliferation from - Occurs by proliferation from margins, migration, multilayering, margins, migration, multilayering, and differentiation of epithelial cellsand differentiation of epithelial cells

HEALING OF SOLID EPITHELIAL HEALING OF SOLID EPITHELIAL ORGANSORGANS

- Following gross tissue damage to - Following gross tissue damage to organs like kidney, liver & thyroid, the organs like kidney, liver & thyroid, the replacement is by fibrous scarreplacement is by fibrous scar

- But if the basement membrane is - But if the basement membrane is intact & only parenchymal damage is intact & only parenchymal damage is present, regeneration occurspresent, regeneration occurs

MANAGEMENT OF MANAGEMENT OF ACUTE WOUNDACUTE WOUND

Follow principles of ALTSFollow principles of ALTS Thorough examination of wound site Thorough examination of wound site

after copious saline irrigation after copious saline irrigation Examine the possible structures that Examine the possible structures that

are damaged under analgesiaare damaged under analgesia Assess the movement and sensationAssess the movement and sensation wound exploration and diagnosiswound exploration and diagnosis

A bleeding wound should be elevated & A bleeding wound should be elevated & pressure pad is appliedpressure pad is applied

WOUND DEBRIDEMENT- wound should WOUND DEBRIDEMENT- wound should be debrided to limit of blood supply, be debrided to limit of blood supply, devitalised tissues must be exciseddevitalised tissues must be excised

Repair of all damaged structures are Repair of all damaged structures are attemptedattempted

Management of Management of Specific woundsSpecific wounds

1. Bites1. Bites

As per aboveAs per above

Antibiotic coverage Antibiotic coverage for aerobic and for aerobic and anaerobic anaerobic orginismsorginisms

2. Haematomata2. Haematomata

Release by incision/aspirationRelease by incision/aspiration

Surgical exploration is case of Surgical exploration is case of calcificationcalcification

3. Degloving3. Degloving

Open Open – ring – ring avulsion injury with avulsion injury with loss of finger skin loss of finger skin

Closed Closed – rollover – rollover injuryinjury

4. Compartment 4. Compartment SyndromeSyndrome Occurs in closed lower Occurs in closed lower

limb injurieslimb injuries Characterised by Characterised by

severe pain, pain on severe pain, pain on passive movement of passive movement of the affected the affected compartment muscles, compartment muscles, distal sensory distal sensory disturbance, absence disturbance, absence of pulse distally.of pulse distally.

treatment: fasciotomytreatment: fasciotomy

5. High pressure 5. High pressure injection injuriesinjection injuries Occurs in person working with Occurs in person working with

cleaning, degreasing and painting cleaning, degreasing and painting devicesdevices

tissue damage depends on toxicity of tissue damage depends on toxicity of substance and injection pressure substance and injection pressure

Treatment is surgical with wide Treatment is surgical with wide exposure, removal of the toxic exposure, removal of the toxic substance and through debridement. substance and through debridement.

Management of Management of chronic chronic woundswounds

1. Leg ulcers1. Leg ulcers

Treatment of the Treatment of the underlying causeunderlying cause

A chronic ulcer A chronic ulcer unresponsive to unresponsive to treatment should be treatment should be biopsied to rule out biopsied to rule out neoplastic changeneoplastic change

Surgical treatment is Surgical treatment is required if non operative required if non operative treatment failstreatment fails

Meshed skin grafts may Meshed skin grafts may be requiredbe required

2. Pressure sores2. Pressure sores

Prevention – good skin carePrevention – good skin care

foam bedsfoam beds

pt. turning at least pt. turning at least every 2hrsevery 2hrs

Preoperative treatment of pressure Preoperative treatment of pressure sore involves adequate debridement sore involves adequate debridement and the use of vaccum assisted and the use of vaccum assisted closure.closure.

Factors that retard Factors that retard wound healingwound healing

1. Local factors1. Local factors

Blood supplyBlood supply Mechanical stressMechanical stress

denervationdenervation Necrotic issueNecrotic issue

Local infectionLocal infection Protection Protection (dressing)(dressing)

Foreign BodyForeign Body Surgical Surgical techniquestechniques

HacmatomaHacmatoma type of tissuetype of tissue

2. Systemic factors2. Systemic factors

AgeAge MalnutructionMalnutruction

AnemiaAnemia obesityobesity

Drugs (steroids, cytotokie, medications)Drugs (steroids, cytotokie, medications) Systemic Systemic infectioninfection

genetic disordersgenetic disorders temperaturetemperature

HormonesHormones trauma, trauma, HypevolemiaHypevolemia

hypoxiahypoxia

DiabetesDiabetes Vit & trace Vit & trace metal metal deficiencydeficiency

Malignant disease.Malignant disease.

COMPLICATIONS OF COMPLICATIONS OF WOUND HEALINGWOUND HEALING

Hypertrophic scar & Hypertrophic scar & keloidkeloid

Wound dehisense & Wound dehisense & ulcerationulceration

ContracturesContractures Wound infectionWound infection Incisional herniaIncisional hernia Implantation cyst Implantation cyst

formationformation PigmentationPigmentation NeoplasiaNeoplasia

Source of informationSource of information

Robin’s text book of pathologyRobin’s text book of pathology Harsh mohan’s text book of Harsh mohan’s text book of

pathologypathology Bailey and love’s book of surgeryBailey and love’s book of surgery Sabiston’s book of surgerySabiston’s book of surgery www.pubmed.comwww.pubmed.com www.google.comwww.google.com