1. WOUND HEALING MBBS, Resident Plastic surgery, HMC, Peshawar ansoor Khan M

2. Complex & dynamic process of restoring cellular structures & tissue layers

3. SCARING Full thickness wounds EPITHELIZATION Partial thickness wounds HEALING w o u n d h e a l i n g

4. Phases of wound healing

5. Inflammatory phase (day1-4)

6. Limit blood loss Debridement Sealing the wound

7. Inflammatory phase Haemostasis Inflammation

8. Vessel damage ---- bleeding---- platelet plug ---- thromboxane A2 --- Vascular contraction and coagulation pathway activation --- fibrin frame work deposition Haemostasis (Activated by intrinsic & extrinsic pathways)

9. Inflammation Serotonin/Histamine --- increased vascular permeability TGF– neutrophil chemotaxis, starts 6-8 hrs, max in 24 hrs Monocyte/ Macrophage– max 3-4 days Phagocytosis, cytokines (IL-1, TNF), mediators (TGF, PDGF, FGF) Activated by platelet secretary products (PDGF, TGF, FGF, Serotonin, Histamine)

10. Proliferative Phase (day 4-21)

11. Filling wound gap with granulation tissue

12. EVENTS Fibroplasia, angiogenesis, contraction, re-epithelization

13. FIBROPLASIA Chemotactic TGF, PDGF, EGF, IL-1 Fibroblasts peaks at 7 th day Collagen & Matrix deposition, Wound contraction 10-21 days

14. ANGIOGENESIS Hypoxia, lactic acidosis, and FGF-1 (most potent), heparin, TGF, prostaglandin Endothelial cells proliferation

15. EPITHELIALIZATION Basal layers thickens, elongates and cells detaches and migrates

16. Tailoring the way reality lives Phase (day 21-2years)

17. S hrinkage L oss of oedema S trength S care contraction

18. EVENTS Regression of vessels & granulation tissue Wound contraction Collagen remodelling (replacing collagen III with I) Maximum strength at the 12 week

19. WOUND CONTRACTION Begin in the proliferative phase (4-5 th day) Continues throughout the healing process Maximum 10-21 day Brings edges close at a rate of 0.6-0.75mm/day Depends on the laxity of the skin

20. LOCAL FACTORS Venn diagram

21. RISK FACTORS RISK FACTORS SYSTEMIC RISK FACTORS RISK FACTORS RISK FACTORS

22. ISCHEMIA Wound healing is a highly energy dependant process

23. Sugar is the main fuel for wound healing ISCHEMIA

24. So it take a rich blood supply to heal a wound ISCHEMIA

25. Initial response neo-vascularization Persistent ischemia results in apoptosis “ ”

26. INFECTION Collagenase production and destruction of collagen

27. FOREIGN BODIES Acts a physical barrier Asylum for bacteria Inability to contract Prevent epithelization

28. HYPOTHERMIA Vasoconstriction and decreased blood supply

29. PAIN Adrenaline surge causing vasoconstriction

30. Keep the wounds wet , warm and comfortable “ ”

31. SMOKING Vasoconstriction Which is not transient— 1 cigarette for 90 min 1 pack for whole day

32. SMOKING Carboxihemoglobin--- O2 carrying capacity. Subcutaneous PO2

33. 1 pack/ day--- 3 times increased chances of flap or graft loss 2 packs/day--- 6 times increased chances of loss of flaps and grafts SMOKING

35. STEROIDS Lysosomal stabalization--- impaired phagocytosis Impairment of chemotaxis of microphages Fibroblast genome inhibition--- decreased collagen, decreased strength and increased dehiscence

36. HEALING SLOWS DOWN WITH AGING

37. CUTIS LAXA SYNDROME

38. EHLER-DANLOS SYNDROME

39. OSTEOGENESIS IMPERFECTA

40. FETAL WOUND HEALING (SCARLESS) ADULT: collagen production, remodelling, scar formation FETAL: Altered growth substances (Tenascin etc), absence of inflammation, deposition of hyaluronic acid rich matrix and deposition of organized collagen leading to regeneration