Wound Management Hameed Ali Al-Timmemi MSc, PhD Surgery Baghdad University Surg Depart Wound Management Hameed Ali Al-Timmemi MSc, PhD

Surgery Baghdad University Surg Depart Referances Fossum,T W., Hedlund, C., Johnso,A., Schul, K., Seim, H., Willard, M., Bahr, A., Carroll, G. and Knap, K. (2007). Small Animal Surgery, 3rd Ed., St. Louis, Missouri Dr H, Al-Timmemmi

Epidermis: outermost layer, avascular Surgery Baghdad University Surg Depart Surgical Anatomy Skin composed of Epidermis: outermost layer, avascular Dermis: lies deep to the epidermis, Associated adnexa: (hypodermis) Dr H, Al-Timmemmi

Subdermal (deep) plexus Cutaneous (middle) plexus Surgery Baghdad University Surg Depart Terminal arteries and veins branch from direct cutaneous vessels and Form Subdermal (deep) plexus Cutaneous (middle) plexus Subpapillary (superficial) plexus Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Wound: Disruption of normal tissue integrity. Wound Healing Surgery Baghdad University Surg Depart Wound: Disruption of normal tissue integrity. Wound Healing Wound healing is a biologic process that restores tissue continuity after injury. It is a combination of Physical Chemical, and Cellular events that restore wounded tissue or replace it with collagen. Dr H, Al-Timmemmi

Wound Classification: A: According to the etiology Abrasion wound Surgery Baghdad University Surg Depart Wound Classification: A: According to the etiology Abrasion wound Laceration wound Avulsion (degloving injuries) wound Puncture wound Crush wound Burn wound Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Closed wound: Skin is contact (not opened) and contusion. Surgery Baghdad University Surg Depart B: According to the skin involvement Open wounds: When the whole thickness of skin is opened (Laceration and skinloss) Closed wound: Skin is contact (not opened) and contusion. Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Dr H, Al-Timmemmi

C: According to the condition (Clinically) of the wound Clean wound Surgery Baghdad University Surg Depart C: According to the condition (Clinically) of the wound Clean wound Clean-contaminated wounds Contaminated wounds Dirty and infected wounds Dr H, Al-Timmemmi

Stages of Wound Healing Surgery Baghdad University Surg Depart Stages of Wound Healing Inflammatory phase: characterized by Increased vascular permeability, Chemotaxis of circulatory cells, Release of cytokines and growth factors, and Cell activation (macrophages, neutrophils, lymphocytes, and fibroblasts). Hemorrhage cleans and fills wounds immediately after injury. Blood vessels constrict for 5 to 10 minutes to limit hemorrhage, But then dilate and leak fibrinogen and clotting elements into wounds.   Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Vasoconstriction is mediated by catecholamines, serotonin, bradykinin, and histamine. Platelet aggregation and blood coagulation form a clot that ensures hemostasis and provides a scaffold for cell migration Platelets also release potent chemoattractants and growth factors (epidermal, platelet-derived, transforming growth factors: a and b) that are necessary in later stages of wound healing Fibrin and plasma transudates fill wounds and plug lymphatics, localizing inflammation and “gluing” wound edges together. Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Inflammatory phase cells such as platelets, mast cells, and macrophages secrete growth factors or cytokines, which initiate and maintain the proliferative phase of healing.   Inflammatory mediators (i.e., histamine, serotonin, proteolytic enzymes, kinins, prostaglandins, complement, lysosomal enzymes, thromboxane, and growth factors) cause inflammation that begins immediately after injury and lasts approximately 5 days.  Dr H, Al-Timmemmi

2. Débridement phase: Surgery Baghdad University Surg Depart 2. Débridement phase: Chemoattractants encourage neutrophils and monocytes to appear in wounds (approximately 6 hours and 12 hours after injury, respectively) Degenerating neutrophils release enzymes and toxic oxygen products that facilitate the breakdown of bacteria, extracellular debris, and necrotic material, and they stimulate monocytes Monocytes are major secretory cells synthesizing growth factors that participate in tissue formation and remodeling Monocytes become macrophages in wounds at 24 to 48 hours. Dr H, Al-Timmemmi

Macrophages secrete Surgery Baghdad University Surg Depart Macrophages secrete Collagenases, removing necrotic tissue, bacteria, and foreign material. Gowth factors andchemotactic d. (i.e., PDGF, TGF-a, b, FGF, and IL-1) can initiate, maintain, and coordinate formation of granulation tissue. Chemotactic factors (i.e., complement, collagen fragments, bacterial endotoxins, and inflammatory cell products) Dr H, Al-Timmemmi

Platelets release growth factors important for fibroblastic activity. Surgery Baghdad University Surg Depart Recruit mesenchymal cells, stimulate angiogenesis, and modulate matrix production in wounds. Platelets release growth factors important for fibroblastic activity. Lymphocytes appear later in the debridement phase Dr H, Al-Timmemmi

3. Repair phase: Surgery Usually begins 3 to 5 days after injury Baghdad University Surg Depart 3. Repair phase: Usually begins 3 to 5 days after injury Macrophages stimulate deoxyribonucleic acid (DNA) and fibroblast proliferation. Cytokines, in concert with extracellular matrix molecules, stimulate fibroblasts in the surrounding tissue to proliferate. A tissue oxygen content of approximately 20 mm Hg and slight acidity also stimulate fibroblast proliferation and collagen synthesis. Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Fibroblasts originate from undifferentiated mesenchymal cells in surrounding connective tissue and migrate to wounds along fibrin strands in the fibrin clot. The amount of collagen reaches a maximum within 2 to 3 weeks after injury. Capillaries invade wounds behind migrating fibroblasts by the process of angiogenesis which relying on interaction of extracellular matrix with cytokines that stimulate migration and proliferation of endothelial cells. Dr H, Al-Timmemmi

GT fills defects and protects wounds. Surgery Baghdad University Surg Depart The combination of new capillaries, fibroblasts, forms bright red, fleshy GT 3 - 5 days after injury.  GT fills defects and protects wounds. It provides a barrier to infection, a surface for epithelial migration, and a source of special fibroblasts (i.e., myofibroblasts), Epithelial repair involves mobilization, migration, proliferation, and differentiation of epithelial cells. Migrating epithelial cells enlarge, flatten, and mobilize, losing their attachments to the basement membrane and other epithelial cells. Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Epithelial cells in the layers behind these altered cells migrate over them until they contact the wound surface. The migrating cells move under scabs and produce collagenase, which dissolves the base of the scab so it can be shed. Wound contraction reduces the size of wounds subsequent to fibroblasts, reorganizing collagen in granulation tissue and myofibroblast contraction at the wound edge Wound contraction involves a complex interaction of cells, extracellular matrix, and cytokines. Wound contraction stops when wound edges meet, when tension is excessive Dr H, Al-Timmemmi

4. Maturation phase Surgery Baghdad University Surg Depart 4. Maturation phase Wound maturation begins once collagen has been adequately deposited in wounds (17 to 20 days after injury) and may continue for years. The cellularity of granulation tissue is reduced as cells die. There is also a reduction in collagen content of the extracellular matrix Dr H, Al-Timmemmi

Collagen synthesis and lysis occur at the same rate in maturing scars. Surgery Baghdad University Surg Depart Nonfunctionally oriented collagen fibers are degraded by proteolytic enzymes (matrix metalloproteinases) secreted by macrophages, epithelial cells, endothelial cells, and fibroblasts within the extracellular matrix. As the number of capillaries in fibrous tissue declines, the scar becomes paler. Scars also become less cellular, flatten, and soften during maturation. Collagen synthesis and lysis occur at the same rate in maturing scars. Dr H, Al-Timmemmi

Type of wound healing Healing by first intention Surgery Baghdad University Surg Depart Type of wound healing Healing by first intention Healing by 2nd intention Healing by 3rd intention Healing by mixed intention Healing under scab: Dr H, Al-Timmemmi

Treatment of infected wound Surgery Baghdad University Surg Depart Treatment of Wounds Clean wounds Contaminated wound Treatment of infected wound Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Wound Closure 1. Primary wound closure: Wounds may be closed immediately (within 1 to 3 days after injury). 2. Delayed primary wound closure: when they are free of infection but before granulation tissue has appeared 3. Secondary closure: after the formation of granulation tissue 4. Secondary intention: allowed to contract and epithelialize Dr H, Al-Timmemmi

Surgery Baghdad University Surg Depart Factors that affect the decision to close wounds include the following: Howlong time that has elapsed since injury. wounds older than 6 to 8 hours are initially treated with bandages Degree of contamination Amount of tissue damage Completeness of debridement Status of the wound's blood supply Dr H, Al-Timmemmi

7. Extent of tension or dead space 8. Location of the wound Surgery Baghdad University Surg Depart 6. The animal's health 7. Extent of tension or dead space 8. Location of the wound Dr H, Al-Timmemmi

Factor effect wound healing: A. Local factors that Influence healing Surgery Baghdad University Surg Depart Factor effect wound healing: A. Local factors that Influence healing 1. Oxygenation 2. Infections: 3. Foreign body 4. Venous sufficiency B. Systemic factors that influence healing Age Sex Hormones Diabetes Dr H, Al-Timmemmi

5. Medications 6. Obesity 7. Nutrition Surgery 4. Stress Baghdad University Surg Depart 4. Stress 5. Medications 6. Obesity 7. Nutrition Dr H, Al-Timmemmi

Complication of wound: Surgery Baghdad University Surg Depart Complication of wound: Bleeding Syncope Shock Traumatic neuralgia Damage to nerve Traumatic emphysema Traumatic fever. Dr H, Al-Timmemmi

11. Venous thrombosis and embolism 12. Gas gangrene Surgery Baghdad University Surg Depart 8. Cellulitis. 9. Erysipelas 10. Septicemia & pyemia. 11. Venous thrombosis and embolism 12. Gas gangrene Dr H, Al-Timmemmi