Wounds

Break in the integrity of skin and tissue Or An injury to living tissue caused by a cut, blow, or other impact, in which the skin is broken. It may or may not associated with destruction of structure or function

Classification of wounds Simple wounds Only skin layer is affected / break Complete wounds Skin and tissue got broken including Vessels, muscles, tendons, ligaments, bones

Open wounds Closed wounds Underlying tissue or muscles or bones are exposed Closed wounds No problems externally, but internal portions are affected

Open wounds Avulsion – complete or partial tearing of skin Laceration –a deep cut or tear of skin or flesh Puncture – a small hole type of injury by long sharp objects, pointing needles or objects Incision – injury caused by sharp objects like blade, knife. Bleeding will be profuse Abrasion – injury caused by rub or scratch with a rough area

Closed wounds Hematoma – any injury to the vessels cause clotting of blood and accumulation in that area. Thus leads to hematoma Crush injury – by accidental pressures, internal tissues/ vessels get damaged. Eg- accidents Contusion or Bruise – superficial injury due to accumulation of blood under tissue. (a type of hematoma)

Clean wound There will not be formation of debris and any signs of inflammation. All clean wounds will heal fast Contaminated wounds Completely with debris and infection. The healing only takes place with proper wound management

Period of healing Acute – heals very fast. Predictable healing period Chronic – long term healing eg- diabetic ulcer

Involvement of part Superficial thickness – only epidermis is affected Partial thickness – includes epidermis and dermis Full thickness – all parts of skin along with muscles, bones with blood vessels and nerves

Surgical wounds Clean surgical wounds – no inflammatory reaction Clean -contaminated surgical wounds – high risk for developing inflammation, infection. Ex – chest procedures Contaminated wounds – wounds come in contacts with contaminants Infected surgical wounds – wounds delayed treatment ex- traumatic wounds, wound contact with pus, fecal matters

Origin Internal – due to impaired immune system or decrease in blood oxygen and nutrients to specialized cells or due to any external force internal organs are being injured External – by penetrating / non- penetrating causes the external part is being injured or due to miscellaneous causes.

Miscellaneous Thermal wounds – extreme hot or cold ex- burns Chemical wounds – exposure / inhalation to chemical. Ex- acids or alkali Bites and stings Electrical – passage of high electrical voltage through body

Wound healing Fundamental property of all living tissues in all species Nursing role – florence nightinale’s definition Preparing a client for the most favorable conditions for healing.

If the wound involves:- Mucus membrane – regeneration will be complete Partial /Full thickness – scar will form as a result of healing CNS tissue – no regeneration

Definition of wound healing Wound healing is a complex and dynamic (active, changing and adapting ) process that results in the restoration of anatomic continuity of structure and function. Components – oxygen, nutrition and growth factors in blood

Phases of wound healing Hemostasis (the process of keeping blood inside a damaged vessel to stop bleeding) and vascular response Inflammatory phase or process Proliferative or resolution phase Maturation/ reconstruction phase

Hemostasis and vascular response Starts within seconds after an injury There will be Vasoconstriction immediately after the injury -to stop bleeding Clot formation - with the help of platelets and stops bleeding Plasma protein – forms fibrous mesh work around wound Combination of clot with platelets with the mesh work occurs to minimize bleeding

Capillary dilation / vasodilation Dilation of vessels for supply of more blood to the area. And plasma will also be supplied Plasma – phagocytes (macrophages, leukocytes , mast cells, neutrophills ) Dilute toxins Carry oxygen and nutrients Due to all these, redness, warmness occurs

Inflammatory phase or process Starts within 4-6 days This phase is a defense mechanism produced by cells or tissues against the microorganisms It limits or eliminate the effects microorganisms

Walling off effect –in the wounded area, there will be presence of microorganism. It can spread through the lymph vessels around it. So The wounded area develops fibrinogen clots around it and these will block the lymph vessels and thus reduce the spreading

WBC’S role They gets activated in inflammation and infection Neutrophills – vital role More neutrophills are transported to the wound area. Blood vessels are made of endothelium (closely packed) and the neutrophills reaches and marginate around the area – marginating / pavementing

Histamine will produce and they dilate the vessels and create the space in between the endothelium in that area. Through theses spaces, nutrients and all needed factors pass to the wound area along with neutrophills The transport of neutrophills though the endothelial space created is called as diapedesis Chemotaxis – the process of movement of neutrophills towards the affected area

Neutrophills (60% of WBC) are also called as poly morphonucleus neutrophills- polys These are secreted either mature (segmented – segs ) Or immature (banded – bands ) The mature ones are phagocytotic If more segs are seen in blood tests, indicated increased phagocytosis If immature or bands is high – less phagocytosis and the problem can be from the bone marrow.

Macrophage – Phagocytosis Activate within 48 hours after injury Removes dead cells or dying cells through phagocytosis Eosinophills and basophills Migrate towards the wounded area basophills – secrete histamine Antihistamines produced by eosinophills

Mediators of phase II Mast cells (produced by plasma cell [antibody producing cells]) – mast cells get activated if any injury occurs and produces :- Histamine Serotonin Leukotrines Prostaglandins – responsible for pain – managed with aspirin(NSAID’S). These are vasodilators

Kinins - Kind of plasma proteins. Bradykinin – action same as prostaglandins and produce pain It increases vascular permeability also Cytokines - Generally for growth and maturation of cells along with immunity development Interleukins – growth and development of cells Interferones – immunity

Proliferative or resolution phase This is an overlapping phase Fibroplasia and Development of granulation tissue – Fibroblasts – the cells that synthesizes the extracellular matrix and collagen and plays a critical role in wound healing By the end of first week, fibroblast are the main cells in the wound area Granulation tissue – they are new connective tissues consist of tiny blood vessels, fibroblasts, inflammatory cells, endothelial cells.

Collagen deposition Collagens are proteins which helps in generation of new cells Angiogenesis (neovascularisation) – development of new blood vessels Wound contraction Ability of wound edges to come together and to contract

Epithelialization Migration of normal epithelial cells from the edge of wounds towards the centre Basal epithelial cells at the wound margin flatten (mobilize) and migrate into the open wound Basal cells at margin multiply (mitosis) in horizontal direction

Epithelialization/Contraction

Epithelialization

Cells activates during IIIrd phase Fibroblast – helps in collagen deposition and granulation tissues Myofibroblast – helps in wound contraction Macrophages – helps in angiogenesis It secretes / stimulate certain factors PDGF – platelet derived growth factor AGF – angiogenitc growth factors TGF- transforming growth factors

Maturation / reconstruction phase It will take weeks, months, years or more Formation of scar and its remodeling Initially scar will be very tight and dark Then thins and becomes white In this phase the disorganized collagen fibers are rearranged and cross linked As the phase progress the tensile (ability to stretch) strength of the wound increases

Wound healing intention Probable process of healing. These are Primary intention – with suturing of wound. Can heal the wound without inflammation. ex -incision and lacerations Secondary intention – keeping wound open. By the time proliferation and maturation occurs slowly and healing occur by scar tissue formation eventually – diabetic wound

Tertiary intention(delayed primary intension) – the contaminated wounds cant kept closed. So cant use primary intension. Only after removing the debris (dead cells) and contaminants primary intension can adopt.

Factors delaying wound healing Disease conditions Diabetes – hyperglycemia can delay developments of collagen Immunosuppressive conditions Oxygen deficit – anemia, inadequate blood supply, foreign body Increased Moisture Increase age – decrease healing Increased mobility Drugs – anticoagulants, - bleeding cant stop

Lack of Personal hygiene Inadequate dressing – too short / too tight Nutritional deficiency – vit c – collagen development protein – repair and development of new cells Zinc – epitheliazation Smoking – o2 saturation will decrease and nicotine is a vasoconstrictor

Edema – increased interstitial pressure thus vasoconstriction Hypovolemia – decreased oxygen, nutrient by decrease blood volume Hemorrhage – blood loss, accumulation in internal bleeding favor microbes multiplication.