4. z
Wound Healing Pathophysiology
• 1.) Inflammatory Phase
• Initial response (Day 1-4 post injury)
• rubor, tumor, dolor, calor
• Platelet aggregation and activation
• Leukocyte (PMNs, macrophages) migration, phagocytosis and
mediator release
• Venule dilation • Exudative • a biologic debridement • In wounds
closed by primary intention, lasts 4 days
5. z
• 2.) Proliferative Phase
• Day 4-42
• macrophage-released growth factors
Fibroblast proliferation
Increased rate of collagen synthesis
• Granulation tissue and neovascularization
• Gain in tensile strength
6. z
• 3.) Remodeling Phase
• 6wks-1 year
• Intermolecular cross-linking of collagen via vitamin C-
dependent hydroxylation
• Characterized by increase in tensile strength • Type III collagen
replaced with type I
• Scar flattens
7. z
TYPES OF WOUND HEALING
1.) Healing by first intention (aka. Primary wound healing or primary
closure)
• wound closed by approximation of wound margins or by placement of a
graft or flap, or wounds created and closed in the operating room.
• Best choice for wounds in well-vascularized areas
• Indications –recent (<24h old)-clean-viable tissue-tension-free
• treated within 24 h, prior to development of granulation tissue.
• epithelialize within 24 to 48 h. Water barrier function restored
can shower or wash.
8. z
2.) Healing by second intention (aka. Secondary wound healing or
spontaneous healing)
• wound left open and allowed to close by epithelialization and
contraction.
• Commonly : management of contaminated or infected wounds. •
without surgical intervention.
• Unlike primary wounds, approximation of wound margins occurs
via reepithelialization and wound contraction by myofibroblasts.
• Presence of granulation tissue. • Complications –late wound
contracture-hypertrophic scarring
9. z
• 3.) Healing by third intention (aka. Tertiary wound healing or delayed
primary closure)
• wounds that are too heavily contaminated for primary closure but appear
clean and well vascularized after 4-5 days of open observation.
• Inflammation reduced bacterial concentration (“debribe”) allow safe
closure.
• Indications :- infected or unhealthy wounds with high bacterial content,-
wounds with a long time lapse since injury, or –wounds with a severe crush
component with significant tissue devitalization.
• Wound edges are approximated within 3-4 days • tensile strength
develops as with primary closure.
10. z
• wound preparation (debridement,cleansing, etc.)
• dress with saline soaked fine mesh gauze
• follow up in 72-96 hours for debridement
• repeat cleansing and closure if no evidence of infection
12. z
Factors that affect wound healing • In general, remember
“DIDN’T HEAL”
• D = Diabetes: -diminishing sensation and arterial inflow ++
acute loss of diabetic control diminished cardiac output, poor
peripheral perfusion, and impaired polymorphonuclear leukocyte
phagocytosis.
• I = Infection: -potentiates collagen lysis. Bacterial
contamination + susceptible host + wound environment = wound
infection. Foreign bodies (including sutures) potentiate wound
infection.
13. z
• D = Drugs: Steroids and antimetabolites impede proliferation of
fibroblasts and collagen synthesis.
• N = Nutritional problems: Protein-calorie malnutrition and
deficiencies of vitamins A, C, and zinc.
• T = Tissue necrosis, from local or systemic ischemia or
radiation injury. Blood supply is important.
14. z
• h = hypoxia: -esp the distal extent of the extremities. Blood
volume deficit, unrelieved pain, or hypothermia sympathetic
overactivity
local vasoconstriction inadequate tissue oxygenation.
• e = excessive tension on wound edges
local tissue ischemia and necrosis.
15. z
A = Another wound: Competition for the substrates required for
wound healing.
• L = Low temperature: (relatively) distal aspects of the upper
and lower extremities (a reduction of 1-1.5°C [2-3°F] from
normal core body temperature) is responsible for slower healing
of wounds at these sites.
16. z
Wound Evaluation
–HISTORY
• identify all extrinsic and intrinsic factors that jeopardize healing
and promote infection– mechanism of injury– time of injury
(accelerated growth phase of bacteria starts at 3 hours post
wound)– environment in which wound occurred
potential contaminants, foreign bodies– species of animal if bite
wound– pt’s medical problems (allergies to medication) / immune
status
• tetanus immunization status
17. z
History
• Immunocompromised
• Bleeding disorder.Prolonged bleeding-. Hematoma can serve
as culture medium for wound infection.
• Peripheral vascular disease
18. z
TYPES OF WOUNDS
• Abrasions Superficial layer of tissue is removed
• Avulsions A section of tissue is torn off (partially or totally)
• Lacerations borders. Tissue is cut or torn. Sharply demarcated
• Puncture Small opening and of indeterminate depth
. • Contusion forceful blow, outer layer of skin intact ; minimal
wound care ; evaluate for possible hematoma
• Combination wound
19. z
Wound Assessment
• Examine for:
– amount of tissue destruction
– degree of contamination
– damage to underlying structures
20. z
•Body Location
–Proximity to Other Structures
–Joints
–Nerves
–Tendons
–Vasculature
–Test integrity of each structure
•Assess laxity/muscle and tendon function
•Assess 2-point discrimination
•Assess vascular supply
21. z
Physical Examination
• Wound Location
– importance in the risk of infection
– high endogenous bacterial counts in hairy scalp, forehead, axilla,
groin, foreskin of penis, vagina, mouth, nails
– wounds in areas of high vascularity more easily resist infection
(scalp, face)
22. z
Wound Preparation
Anesthesia • Topical
– Solution or paste– LET– TAC– EMLA
• Local
– Direct infiltration
– 1% lidocaine with or without epinephrine
– Bupivicaine for longer acting anesthesia
• Regional Block
– Local infiltration proximally in order to avoid tissue disruption
– Smaller amount of anesthesia required
23. z
Wound Preparation – Hemostasis
• Direct Pressure–Usually best choice
• Ligatures– Use a tourniquet
• Chemicals–Epinephrine–Gelfoam–Oxycel–Actifoam
• Cautery
24. z
Wound Preparation – Foreign Body Removal
• Suspect with point tenderness
• Visual inspection (to the apex)
• Imaging– Glass, metal, gravel fragments >1mm should be
visible on plain radiographs– Organic substances and plastics
are usually radiolucent
• Always discuss and document possibility of retained foreign
body
25. z
Wound preparation : CLEANING
• high pressure irrigation (Normal Saline)
• min 100-300 ml with continued irrigation
• at least 8 psi force to the wound
the irrigation fluid dislodges foreign bodies, contaminants, and
bacteria.
• A simple device setup 30-60 ml syringe and an 14-gauge
angiocatheter.
27. z
Indications for systemic antibiotic for traumatic wounds
• Injury 6 hours old on the extremities
• Injury 24 hours old on the face and scalp
• Tendon, joint, or bony involvement
• Cartilage involvement
• Mammalian bite
• Co-morbidity (diabetes mellitus, extremes of age, steroid use, morbid obesity)
• Puncture wound
• Complex intraoral wound
28. z
Wound preparation –Tetanus prophylaxis
• Clean wounds
– Incompleted immunization toxoid
– >10 years, then give toxoid
• Tetanus prone wound
– Incompleted immunization Toxoid & immunoglobulin
– > 5 years, give toxoid
29. z
WOUND CLOSURE
Wound closure in relation to time
• Primary closure– Suture, staple, adhesive, or tape
– Performed on recently sustained lacerations: <12 hours
generally and <24 hours on face
• Secondary closure– Secondary intent– Allowed to granulate
• Tertiary closure– Delayed primary (observed for 3-4days)
31. z
Suture Material
• Absorbable
– Chromic catgut ( natural monofilament)
– Vicryl (synthetic braided)
– PDS II (synthetic monofilament)
• Non-Absorbable
– Silk (natural braided)
– Ethilon (synthetic monofilament) •
Monofilament (smooth but stiff) vs. Braided (has
32. z
After care
•Wound Dressings
• Maintain dry –24 –48 hours–Augments reepithelialization
•“Water-Tight” after 48 hours
•Bandages–Soft-splint–Absorb exudates–Protects Wound–
Protects knots
33. z
Suture removal guide
Face 3-5
Arm 7 days
Anterior Trunk 7 days
Back 10-14 days
Scalp. 10-14
Feet and hand ….10-14 days
Joints. 10-14
34. z
Wounds appropriate for consultation/referral
• Primary provider is unable to perform optimal repair
– Skill level does not match complexity of wound
– Practice setting is too busy to allow adequate time for repair
• Underlying injury– Tendon ,Nerve, Vascular,Joint involvement or
underlying fracture
Eyelid: tarsal plate or lacrimal duct involvement
• Patient requests specialist •
Operative repair necessary– Skin grafting– Flap creation or rotation