陳杰峰 醫師 :firstname.lastname@example.org 外科傷口分類 Class Ⅰ : 乾淨 Clean Elective surgical incisions not involving the GI, GU, or respiratory tracts No inflammation encountered No drains Infection rate Class Ⅱ : 乾淨疑染污 Clean - contaminated GI or respiratory tract entered during elective surgery, with minimum spillage (appendectomy) GU or biliary tract entered, but urine or bile is not infected Minor breaks in technique Infection rate <5-10%
陳杰峰 醫師 :email@example.com 外科傷口分類 Class Ⅲ : 染污 Contaminated Fresh trauma wounds Gross spillage from GI tract GU or biliary tract entered, and urine or bile is infected Nonpurulent inflammation Major break in sterile technique No drains Infection rate<10-20% Class Ⅳ : 骯髒 / 感染 Dirty/Infected Traumatic wound with retained devitalized tissue Contaminated or clinically infected prior to operation (PPU) Wounds with purulent exudate, acute bacteria inflammation Open > 4hrs Infection rate<20-40%
陳杰峰 醫師 :firstname.lastname@example.org Categories of Wound Healing 1. Primary closure: Within 24 hours. Good scar. 2. Delayed Primary Closure: Cleansed, debrided for 4 to 5 days Contaminated, human or dog bite 3. Secondary closure: Heal by granulation and reepithelialization infected wound scar 4. Partial thickness wounds
陳杰峰 醫師 :email@example.com Categories of Wound Healing Category 1 Primary wound healing or healing by first intention occurs within hours of repairing a full-thickness surgical incision. This surgical insult results in the mortality of a minimal number of cellular constituents.
陳杰峰 醫師 :firstname.lastname@example.org Categories of Wound Healing Category 2 (Tertiary wound closure) delayed primary wound healing This type of healing may be desired in the case of contaminated wounds. By the fourth day, phagocytosis of contaminated tissues is well underway, and the processes of epithelization, collagen deposition, and maturation are occurring. Foreign materials are walled off by macrophages that may metamorphose into epithelioid cells, which are encircled by mononuclear leukocytes, forming granulomas. Usually the wound is closed surgically at this juncture, and if the "cleansing" of the wound is incomplete, chronic inflammation can ensue, resulting in prominent scarring.
陳杰峰 醫師 :email@example.com Categories of Wound Healing Category 3 (secondary healing) healing by secondary intention. In this type of healing, a full-thickness wound is allowed to close and heal. inflammatory response granulomatous tissue is fabricated contraction of wounds. Fibroblastic differentiation into myofibroblasts, which resemble contractile smooth muscle, is believed to contribute to wound contraction. These myofibroblasts are maximally present in the wound from the 10th-21st days.
陳杰峰 醫師 :firstname.lastname@example.org Categories of Wound Healing Category 4 In wounds that are partial thickness, involving only the epidermis and superficial dermis, epithelization is the predominant method by which healing occurs. Epithelization epithelial cells migrate and replicate via mitoses and traverse the wound. Wound contracture is not a common component of this process if only the epidermis or epidermis and superficial dermis are involved STSG donor site.
陳杰峰 醫師 :email@example.com SEQUENCE OF EVENTS IN WOUND HEALING Initial phase - Hemostasis Second phase – Inflammation Third phase - Granulation Fourth phase - Remodeling
陳杰峰 醫師 :firstname.lastname@example.org Initial phase - Hemostasis Following vasoconstriction, platelets adhere to damaged endothelium The inflammatory phase is initiated by the release of numerous cytokines by platelets. Alpha granules liberate platelet-derived growth factor (PDGF), platelet factor IV, and transforming growth factor beta (TGF-b), while vasoactive amines such as histamine and serotonin are released from dense bodies found in thrombocytes.
陳杰峰 醫師 :email@example.com Growth Factors of Wound Healing Cytokine:PDGF Cell of Origin: Platelets, Macrophages, Endothelial cells Function Cell chemotaxis Mitogenic for fibroblasts Stimulates angiogenesis Stimulates wound contraction
陳杰峰 醫師 :firstname.lastname@example.org Growth Factors of Wound Healing Cytokine:TNF Cell of Origin: Macrophages, Mast cells, T lymphocytes Function Activates macrophages Mitogenic for fibroblasts Stimulates angiogenesis
陳杰峰 醫師 :email@example.com Growth Factors of Wound Healing Cytokine:Thromboxane A2 Cell of Origin: Destroyed wound cells Function Potent vasoconstrictor
陳杰峰 醫師 :firstname.lastname@example.org Initial phase - Hemostasis PDGF is chemotactic for fibroblasts and along with TGF-b is a potent modulator of fibroblastic mitosis, leading to prolific collagen fibril construction in later phases. Fibrinogen is cleaved into fibrin and the framework for completion of the coagulation process is formed. Fibrin provides the structural support for cellular constituents of inflammation. This process starts immediately after the insult and may continue for a few days.
陳杰峰 醫師 :email@example.com Second phase - Inflammation Within the first 6-8 hours, the next phase of the healing process is underway, with polymorphonuclear leukocytes (PMNs) engorging the wound. TGF-b facilitates PMN migration from surrounding blood vessels where they extrude themselves from these vessels. The PMNs attain their maximal numbers in 24-48 hours and commence their departure by hour 72. Other chemotactic agents are released, including fibroblastic growth factor (FGF), transforming growth factors (TGF-b and TGF-a), PDGF, and plasma-activated complements C3a and C5a (anaphylactic toxins). They are sequestered by macrophages or interred within the scab or eschar (Habif, 1996).
陳杰峰 醫師 :firstname.lastname@example.org Second phase - Inflammation As the process continues, monocytes also exude from the vessels. These are termed macrophages. The macrophages continue the cleansing process and manufacture various growth factors during days 3-4. The macrophages orchestrate the multiplication of endothelial cells with the sprouting of new blood vessels, the duplication of smooth muscle cells, and the creation of the milieu created by the fibroblast. Many factors influencing the wound healing process are secreted by macrophages. These include TGFs, cytokines and interleukin-1 (IL-1), tumor necrosis factor (TNF), and PDGF.
陳杰峰 醫師 :email@example.com Third phase - Granulation This phase consists of different sub-phases: fibroplasia, matrix deposition, angiogenesis re-epithelialization In days 5-7, fibroblasts have migrated into the wound, laying down new collagen of the subtypes I and III. Early in normal wound healing, type III collagen predominates but is later replaced by type I collagen.
陳杰峰 醫師 :firstname.lastname@example.org Third phase - Granulation Tropocollagen is the precursor of all collagen types and is transformed within the cell's rough endoplasmic reticulum, where proline and lysine are hydroxylated. Disulfide bonds are established, allowing 3 tropocollagen strands to form a triple left-handed triple helix, termed procollagen. As the procollagen is secreted into the extracellular space, peptidases in the cell wall cleave terminal peptide chains, creating true collagen fibrils.
陳杰峰 醫師 :email@example.com Third phase - Granulation Angiogenesis is the product of parent vessel offshoots. The formation of new vasculature requires extracellular matrix and basement membrane degradation followed by migration, mitosis, and maturation of endothelial cells. Basic FGF and vascular endothelial growth factor are believed to modulate angiogenesis.
陳杰峰 醫師 :firstname.lastname@example.org Third phase - Granulation Re-epithelization occurs with the migration of cells from the periphery of the wound and adnexal structures. This process commences with the spreading of cells within 24 hours. Division of peripheral cells occurs in hours 48-72, resulting in a thin epithelial cell layer, which bridges the wound. Epidermal growth factors are believed to play a key role in this aspect of wound healing. This succession of subphases can last up to 4 weeks in the clean and uncontaminated wound
陳杰峰 醫師 :email@example.com Fourth phase - Remodeling After the third week, the wound undergoes constant alterations, known as remodeling, which can last for years after the initial injury occurred. The collagen deposition in normal wound healing reaches a peak by the third week after the wound is created.
陳杰峰 醫師 :firstname.lastname@example.org Fourth phase - Remodeling Contraction of the wound is an ongoing process resulting in part from the proliferation of the specialized fibroblasts termed myofibroblasts, which resemble contractile smooth muscle cells. Wound contraction occurs to a greater extent with secondary healing than with primary healing. Maximal tensile strength of the wound is achieved by the 12th week, and the ultimate resultant scar has only four fifths, or 80%, of the tensile strength of the original skin that it has replaced.
陳杰峰 醫師 :email@example.com Contraction and Contracture When inadequate skin is present, the process of contraction results in a scar deformity called a contracture.
陳杰峰 醫師 :firstname.lastname@example.org Animal Bite of Face Copious irrigation, excision Wound repair still attempted Antibiotics Rabid dogs: 10~12%. Incubation period 2~8 weeks. Vaccination within the incubation
陳杰峰 醫師 :email@example.com Antibiotic Prophylaxis for Mammalian Bites Medeiros I, Saconato H, 2001 There is no evidence that the use of prophylactic antibiotics is effective for cat or dog bites. There is evidence that the use of antibiotic prophylactic after bites of the hand reduces infection but confirmatory research is required.
陳杰峰 醫師 :firstname.lastname@example.org ANTIBIOTIC PROPHYLAXIS Prophylaxis should be started preoperatively (in most circumstances), ideally within 30 minutes of the induction of anaesthesia. Prophylaxis should be administered immediately before or during a procedure. SIGN, Antibiotic Prophylaxis in Surgery, 2000
陳杰峰 醫師 :email@example.com INDICATIONS FOR SURGICAL ANTIBIOTIC PROPHYLAXIS There are multiple risk factors involved: · ASA scores > 2 · length of preoperative stay in the hospital > 3 days · compromised host defenses. · insertion of implants and grafts. · surgical wound class and duration of surgery. CLINICAL PRACTICE GUIDELINES-Antibiotic Prophylaxis. MINISTRY OF HEALTH MALAYSIA, 2002
陳杰峰 醫師 :firstname.lastname@example.org ASA Score Physical Status The American Society of Anaesthesiologists (ASA) has devised a preoperative risk score based on the presence of co-morbidities at the time of surgery 1 A normal healthy patient 2 A patient with a mild systemic disease 3 A patient with a severe systemic disease that limits activity, but is not incapacitating 4 A patient with an incapacitating disease that is a constant threat to life 5 A moribund patient not expected to survive 24 hours with or without operation CLINICAL PRACTICE GUIDELINES-Antibiotic Prophylaxis. MINISTRY OF HEALTH MALAYSIA, 2002
Ref: New Zealand Guidelines Group (NZGG). Handbook for the preparation of explicit evidence-based clinical practice guidelines, 2001 p44.
陳杰峰 醫師 :email@example.com Compression for Preventing Recurrence of Venous Ulcers (Cochrane Review) Nelson EA, Bell-Syer SEM, Cullum NA, 2001 Compliance rates were significantly higher with medium compression than with high compression hosiery. Not wearing compression was associated with recurrence in both studies identified in this review. Recurrence rates may be lower in high compression hosiery than in medium compression hosiery.
陳杰峰 醫師 :firstname.lastname@example.org Compression for Venous Leg Ulcers Cullum N, Nelson EA, Fletcher AW, Sheldon TA, 2001 Compression increases ulcer healing rates compared with no compression. Multi-layered systems are more effective than single-layered systems. High compression is more effective than low compression.
陳杰峰 醫師 :email@example.com Electromagnetic Therapy for the Treatment of Venous Leg Ulcers Flemming, K. Cullum, N, 2001 There is currently no reliable evidence of benefit of electromagnetic therapy in the healing of venous leg ulcers.
陳杰峰 醫師 :firstname.lastname@example.org Laser Therapy for Venous Leg Ulcers Flemming, K. Cullum, N, 2001 One small study suggests that a combination of laser and infrared light may promote the healing of venous ulcers, however more research is needed.
陳杰峰 醫師 :email@example.com Oral Zinc for Arterial and Venous Leg Ulcers Wilkinson EAJ, hawke CI, 2001 Overall, oral zinc sulphate does not appear to aid healing of leg ulcers.
陳杰峰 醫師 :firstname.lastname@example.org Pentoxifylline Pentoxifylline ( ‘ Trental 400 ’ ) for Treating Venous Leg Ulcers Jull AB, Waters J, Arroll B, 2001 Pentoxifylline appears to be an effective adjunct to compression bandaging for treating venous ulcers. No cost effectiveness data available It not be considered a routine adjunct Gastrointestinal disturbances (indigestion, diarrhoea and nausea) are the most frequent adverse effect.
陳杰峰 醫師 :email@example.com Skin Grafting for Venous Leg Ulcers Jones JE, nelson EA, 2001 There is limited evidence that artificial skin used in conjunction with compression bandaging, increases the chance of healing a venous ulcer compared to compression alone.
陳杰峰 醫師 :firstname.lastname@example.org 以超音波治療靜脈性小腿潰瘍 Therapeutic ultrasound for venous leg ulcers (Cochrane Review)Flemming K, Cullum N The available evidence does suggest a possible benefit of ultrasound therapy in the healing of venous leg ulcers. however only seven small studies were identified, and this conclusion needs interpreting with caution. amendment to this systematic review was last made on 05 July 2000
陳杰峰 醫師 :email@example.com EMLA provides effective pain relief for venous leg ulcer debridement however, the effect of the product on ulcer healing is unknown. There were no trials addressing the treatment of persistent pain (between and at dressing changes) and further research is warranted. Topical Agents or Dressings for Pain in Venous Leg Ulcers Flemming K, Cullum N, amendment to this systematic review was last made on 07 November 2002