WOUND HEALING

HEALING OF WOUNDS

Skin is composed of 3 layersEpidermisDermisHypodermis or Subcutis

Plays role in:Strength & Elasticity of skinRepair of skinFunctions Of SkinPreservation of shapeProtection: physical, chemical & infectious injuriesthermoregulation Causal ForceWound

Blunt rough AbrasionsBlunt (smooth or rough)Bruises Heavy blunt Lacerations Sharp edged Cuts Sharp pointed StabsMissileGunshotHeat, chemicals Burns & Electric current

TYPES OF WOUNDSAbrasions Blunt force with a rough surfaceDestruction of superficial layer of skin (epidermis and part of dermis)Sliding or pressure abrasions2. Bruises (Contusions)Blunt forceinjury of subcutaneous B.V. May be accompanied by abrasions or lacerations (injury of skin)3. LacerationsExtensive blunt force tissue splitting

SLIDING ABRASIONS

RTA: PRESSEURE ABRASIONS

Assault- Multiple recent bruises

OLD BRUISE

LACERATION4. Incised (Cut) WoundSharp force5. Stab WoundPointed sharp force penetrating wound6. Gunshot woundA missile with a high velocity loss of tissueMay be 2 wounds (Entry and Exit)

CUT WOUND

STAB WOUND

C O N T A C T F I R I N G15

D I S T A N T F I R I N G16Wound healing follows SPECIFIC PHASES which may overlapCoagulationInflammationMigration/Proliferation Angiogenesis Epithelialization FibroplasiaRemodelingThree basic classifications exist:

Healing by Primary intention

Healing by Secondary Intention

Delayed Primary healing PRIMARY UNION (Healing by 1st intention) Clean linear wound /surgical incision (wound edges are next to each other - sligtht tissue damage) Space fills with clotted bloodInfiltration with Inflammatory CellsMitoses of basal epitheliumDehydration at surface scabMinimal scarring occurs

HEALING BYPRIMARY UNION

HEALING BY SECONDARY INTENTIONMore extensive tissue destruction, gradually filled-in and replaced by new connective tissueGranulation results in a broader scar Healing process is slow due to drainage from infectionWound care must be performed daily to remove wound debris & allow granulation tissue formation

HEALING BY2ry INTENTIONSCAR Tertiary Intention (Delayed primary closure)Grossly contaminated woundsThe wound is purposely left open The wound is initially cleaned, debrided and observed Wound edges are approximated within 3-4 days and tensile strength develops as with primary closure

SCHEMATIC DIAGRAM OF THE PHASES OF WOUND HEALING