Chapter 2: Wound Management Products

Transcription

1 Chapter 2: Wound Management Products 4 Contact Hours By Kiran Panesar, BPharm (Hons), MRPharmS, RPh, CPh. Kiran has over 15 years of experience as a pharmacist, pharmacy consultant and pharmacy manager. In addition to authoring her own articles for publication, and presenting pharmacy topics as a guest speaker, she edits and reviews articles for the US Pharmacist. Author Disclosure: Kiran Panesar and Elite Professional Education, LLC. do not have any actual or potential conflicts of interest in relation to this lesson. Universal Activity Number (UAN): H01-T Activity Type: Knowledge-based Initial Release Date: June 1, 2015 Expiration Date: May 31, 2017 Target Audience: Pharmacy Technicians in a community-based setting. To Obtain Credit: A minimum test score of 70 percent is needed to obtain a credit. Please submit your answers either by mail, fax, or online at PharmacyTech.EliteCME.com. Questions regarding statements of credit and other customer service issues should be directed to This lesson is $ Educational Review Systems is accredited by the Accreditation Council of Pharmacy Education (ACPE) as a provider of continuing pharmaceutical education. This program is approved for 4 hours (0.4 CEUs) of continuing pharmacy education credit. Proof of participation will be posted to your NABP CPE profile within 4 to 6 weeks to participants who have successfully completed the post-test. Participants must participate in the entire presentation and complete the course evaluation to receive continuing pharmacy education credit. Learning objectives Summarize the anatomy and physiology of the skin. Discuss the factors that affect skin integrity. Discuss wounds and the wound healing process. List the most commonly encountered wounds and the major classifications of wound types. Discuss factors that delay the wound healing process. Introduction Pharmacy technicians are key in helping health care professionals make choices for wound care products. Furthermore, they are an excellent point of call for patients wanting to learn more about the selected product and how to use it correctly. In this course, we discuss Identify the presentation, indications and methods of use for each dressing type and other wound management products. Discuss the most appropriate wound products for commonly encountered wounds and how to select the products for pressure ulcers, arterial ulcers, venous ulcers, diabetic ulcers, surgical wounds and burns. the basics of the skin and wounds and the natural wound healing process. The second part of the course reviews the wound care products available to augment this process, how to choose the correct product, and what new products to expect in the near future. Anatomy and physiology of the skin The skin is the largest organ of the body, making up to 16 percent of the body weight. It weighs about 5-8 pounds in an adult and can spread across 20 square feet. 1 Five layers of the skin The skin consists of five layers: Epidermis: The external layer mainly composed of layers of keratinocytes. Dermis: A supportive connective tissue between the epidermis and the underlying subcutis. This layer contains the sweat glands, hair roots, nerve cells and fibers as well as blood vessels. Subcutaneous tissue: Loose connective and fat tissue beneath the dermis. Fascial layer: Connects the subcutaneous layer and the above layers to the muscle tissue. Muscle tissue: Keeps the muscles moving by absorbing oxygen. 1 One centimeter of skin contains: 15 sebaceous glands. 3 yards of blood vessels. 100 sweat glands. 3,000 sensory cells. 4 yards of nerves. 300,000 epidermal cells. 10 hair follicles. 1 The skin is dynamic layer in a constant state of change in which the cells of the outer layers are continuously shed and replaced by cells moving up from the lower layers. 1 PharmacyTech.EliteCME.com Page 9

2 Epidermis The epidermis is the thin, outermost layer of the skin that continually regenerates every days from the basal cell layer. 1 It functions as a barrier to water loss and protects against chemicals, pathogens and mechanical damage. The thickness of the epidermal layer varies between different parts of body from as thin as 0.05 mm on the eyelids to mm on the soles of the feet. 1 The epidermis is stratified squamous epithelium that contains four types of cells: Keratinocytes: These are the most abundant cells in the epidermis. They produce tough keratin that forms the outer protective layer of the skin. The keratinocytes are linked by protein bridges called desmosomes. The different stages of keratin maturation result in four separate layers of the epidermis. Dermis The dermis is a strong structural matrix and is the thickest layer of the skin. Three major protein fibers provide this layer with mechanical strength: collagen, elastin and reticular. The dermis consists of blood vessels, nerves, hair, nails and skin glands. 1 The dermis has a number of roles to play: Supplies the epidermis with nutrients. Provides mechanical support to the epidermis. Regulates heat, immune response and receptor for pain and cold sensations. Subcutaneous tissue The subcutaneous tissue layer is made up of loose connective tissue and fat. This layer can be up to 3 cm thick around the abdomen. It is located directly beneath the dermis and houses major vessels, lymphatics and nerves. 1 The fatty layer provides insulation for heat Melanocytes: These produce the pigment that gives the skin its color by producing the brown pigment melanin. The melanin absorbs harmful ultraviolet rays. Langerhans cells: These present an antigen to helper T cells, thereby facilitating their responsiveness to skin-associated antigens. Granstein cells: These interact with suppressor T cells, possibly regulating skin-activated immune responses. 1 The four layers of the epidermis are the: Stratum basale: the innermost basal or germinative layer. Stratum spinosum: the spinous or prickle cell layer. Stratum granulosum: granular cell layer. Stratum corneum: the outermost horny layer. 1 The dermis is comprised of two layers: A thin papillary layer. A thicker reticular layer. Collagen and elastin provide tensile strength. Collagen contributes to about 70 percent of the skin s dry weight. Elastin fibers that interconnect with collagen ensure that the skin remains pliable, while proteoglycans provide viscosity and hydration. The breakdown of collagen and elastin contributes to the formation of wrinkles. This normal process of aging is enhanced by overexposure to sunlight.1 and cold, absorbs shock, and reserves calories that may be used during illness and starvation. It is this layer that becomes considerably thinner as an individual ages. 1 Fascial layer The fascial layer is a tough, flexible skin layer that gives rise to fibers. Fascia is the Latin term for band or bandage. Muscle layer This layer consists of muscles that have a high metabolic demand, and is very sensitive to oxygen flow. Functions of the skin 1 The skin is a sensory organ that has a protective role in the body s defense mechanism. The functions of the skin include: Protection: The skin acts as a physical barrier against trauma, bacteria, loss of fluids and proteins. In doing so, it protects the body from mechanical injury. Furthermore, the Langerhans cells, tissue macrophages and mast cells found in the skin layers provide immune protection. The melanin found in the melanocytes of the skin protects against UV radiation. Sensation: The skin has numerous nerve endings that relay messages of pain, pressure and temperature to the brain. Damage to these sensory pathways increases the chances of injury. Thermoregulation: Skin regulates the body temperature through an interaction between nerves, blood vessels and glands. Under Skin integrity Because of the number of vital functions the skin has in the body, it is important that the integrity and normal processes of the skin are maintained. However, there are certain factors that alter the integrity of the skin. These include: Page 10 conditions of raised body temperature, the arteries in the skin dilate, and blood flow and sweat production increases, allowing the body to cool. Excretion: There are more than 2 million pores in the skin that excrete water and toxins from the body. It is estimated that on average, an adult loses about 500 ml of water through the skin in a day. Metabolism: Vitamin D is synthesized in melanocytes upon exposure to the sun. From here it is absorbed into the body, where it assists with the mineralization of bones and teeth. Social interaction: The appearance of an individual s skin is linked to self-esteem and confidence. Damage to the skin can have physiological as well as psychological effects. Age: At birth, the skin and nails are thin and gradually thicken with age. During adulthood, the process of skin thinning begins, leading to the formation of lines and wrinkles. Elderly individuals have thin, fragile skin with poor blood circulation. This means that PharmacyTech.EliteCME.com

3 wounds form more quickly and heal more slowly. The production of vitamin D also decreases, as does the production of oil in the glands, leading to dryness, scales and itch. Sun: Overexposure to the sun can lead to dry skin with wrinkling and irregular pigmentation. Furthermore, the epidermis thickens and the dermal vessels dilate. Prolonged exposure to the sun reduces the concentration of the Langerhans cells by 50 percent. Cosmetics: Soaps remove the lipid coating of the skin and reduce the skin s water-holding ability. Alkaline soaps may increase Wounds A wound is any process that leads to the disruption of the normal architecture and function of the tissue. 2 Wounds can be described as either: Closed wounds, such as a bruises or sprains. Open wounds, such as an abrasions, lacerations, avulsions, ballistic, hemia, or surgical wounds. Hemostasis phase During hemostasis, epinephrine is released in an attempt to minimize bleeding into the soft tissues. It happens from initial injury to Inflammatory phase The inflammatory phase follows the hemostasis phase from 0 to 3 days post-injury. Part of the body s normal defense mechanism, the inflammatory stage is essential to the healing process and occurs within seconds of injury. 3 It involves cleaning up the wound of cellular debris by leukocytes and macrophages. There is immediate vasoconstriction of the damaged blood vessels and coagulation to limit blood loss. 4 Platelets are attracted to the damaged blood vessels, and the coagulation cascade is initiated, leading to a platelet plug that is later stabilized by fibrin. 4 Following this, histamine and other chemical mediators are released from the damaged cells, resulting in vasodilation. 3 Vasodilation Proliferation Also known as the fibroblastic or regenerative phase, proliferation typically occurs 3 to 21 days post-injury, during which angiogenesis and granulation tissue formation occur.6 Macrophages, fibroblasts, immature collagen, blood vessels, and ground substance make up the granulation tissue that fills the wound s cavity. Granulation tissue, comprised of macrophages, fibroblasts of immature collagen, blood vessels and ground substance, is formed. Fibroblasts play two roles in Maturation The maturation phases can take anywhere from 21 days post-injury and can last up to 1½ years later. 4 Fibroblasts, MMPs and growth factors are critical in this phase, during which collagen fibers crosslink and reorganize, and the strength of the scar increases. 7 The entire process of wound healing is dependent upon cytokines, 8 chemicals that are released by cells to alter the activity of surrounding cells. 8 One cytokine can trigger different responses in different cells, depending upon the target cell. Cytokines are becoming a target for newer wound healing products. 8 Some of the most important cytokines in wound healing are: Transforming growth factor alpha (TGF-α), which is released by macrophages and promotes migration and proliferation of a variety of cells. the skin s ph, which may change the ability of the skin to resist bacteria. Diet: A healthy, well-balanced diet is required for normal skin integrity. Drugs: Corticosteroids reduce the thickness of the skin and interfere with the synthesis of collagen. Disease processes: Various diseases alter nutritional status and oxygenation. The management of closed wounds is beyond the scope of this course. The healing of a wound is a highly complex process involving an interplay of cellular, physiological, biochemical and molecular processes that can be divided into four phases: hemostasis, inflammation, proliferation and maturation. These lead to the restoration of cell structures and tissue layers after an injury. approximately three hours post-injury. Platelet cells form a clot and release cytokines. releases growth factors and brings white blood cells to the area, leading to the release of other chemical mediators that are essential for wound healing. 4 Some of these mediators increase capillary permeability, causing exudate to be released into the wound area. 3 Exudate is a broad term used to describe the fluid that is produced by wounds following hemostasis. It primarily consists of water and may include proteins, electrolytes, nutrients, proteases, growth factors, white blood cells, platelets and inflammatory mediators. 5 Healthy exudate is a pale amber color, odorless and watery and is a sign of healing. 5 Neutrophils in the exudate serve to remove foreign material and dead or dying cells and attract macrophages to the area. 4 wound healing process; they stimulate the production of collagen and elastin that increase the strength of the wound, and they stimulate the growth of new blood vessels. 4 As granulation tissue fills the wound site, the edges of the wound pull together, decreasing the surface of the wound. Epithelialization in the final step in which the epithelial cells migrate from the wound edges and the wound is finally covered, resulting in the formation of a scar. 6 Fibroblast growth factor (FGF) is released by macrophages and endothelial cells. It causes angiogenesis and fibroblast proliferation. Transforming growth factor beta1 and beta 2 are secreted by platelets and macrophages. They lead to epidermal cell motility, chemotaxis of macrophages and fibroblasts, synthesis and remodeling of the extracellular matrix. Platelet-derived growth factor (PDGF) are secreted by platelets, macrophages and epidermal cells. These cause fibroblast and macrophage chemotaxis and proliferation. 8 PharmacyTech.EliteCME.com Page 11

4 Acute wounds Acute wounds are usually caused by trauma or injury and heal easily by themselves and require very little care, such as burns. 9 The wound undergoes three distinct phases: Phase 1: The inflammatory, defensive or reaction phase that normally lasts 4-6 days. Burns Burns are acute wounds that can be caused by several external factors, such as exposure to chemicals, heat or flames. 9 There are four types of burns: Thermal burns, caused by extreme heat or cold. Chemical burns, caused by skin contact or inhalation with a caustic agent. Electrical burns, caused by a live electrical current. Radiation burns, caused by overexposure to the sun or radioactive materials. The scale used to measure the level of tissue injury in burns describes the burns by degrees: superficial, partial thickness or full thickness. 9 The spread of the burn injury is measured in terms of the body that it affects and is calculated using the rule of nines. 9 The different parts of the body are divided as shown in the table below. Chronic wounds Chronic wounds are those that take longer than 21 days and sometimes even years to heal. 9 This can be due to various factors, including: Pressure. Poor nutritional status. Disease. Poor circulation. A chronic wound is usually in an inflammatory or proliferative state and requires a comprehensive therapeutic approach. 9 When managing chronic wounds, several treatment modalities may have to be incorporated into the treatment plan, including nutritional support, improvement of circulation and management of incontinence. 9 Pressure ulcers Pressure ulcers are sometimes referred to as pressure sores, bedsores or decubitus ulcers that occur when a soft tissue is compressed between two hard surfaces. 9 These are commonly found in the sacrum and coccyx, the trochanter and the heels and ankles. 9 The first step in the treatment of pressure ulcers is to remove the source of pressure. The time it takes for the pressure ulcer to heal varies among patients and is dependent upon a number of factors, including the patient s nutritional status. 9 Pressure ulcers can be classified into four stages based upon the depth of the ulcers. Classification helps in developing a treatment protocol, selecting a reduction support surface, and obtaining reimbursement for the wound care management products. 9 Arterial ulcers Arterial ulcers occur in the lower extremities of the body, usually between the ankles, the toes and other areas that are prone to rubbing from footwear. Arterial ulcers occurs when damaged arteries decrease the blood flow to the tissue, leading to lack of blood flow and resulting in consequential cell death. 9 It is useful to note that arterial ulcers can be perpetuated by smoking, vascular disease or diabetes. 9 Page 12 Phase 2: Proliferation phase that lasts from 4-24 days. Phase 3: The maturation or remodeling phase that lasts 21 days to as much as 24 months. Body part Percentage of body surface area (BSA) Head 9 Chest 18 Back 18 Right arm 9 Left arm 9 Right leg 18 Left leg 18 Genitals 1 Hence, a burn covering the arm and chest of a small child would total 27 percent of the total body surface area (9 percent for the arm and 18 percent for the chest). 9 The exudate of chronic wounds contains higher levels of neutrophils, pro-inflammatory cytokines, biofilm phenotype bacteria and deleterious protein digesting enzymes (matrix metalloproteinases, MMPs). 8 In the right amounts, MMPs can aid wound healing by promoting cell migration, remodeling and breaking down damaged extracellular matrix. 8 Excessive MMPs, however, can cause increased degradation of cellular components. Because chronic wound exudate is irritating to periwound skin and leads to contact dermatitis and allergic reactions, the MMPs need to be inhibited. 8 Examples of exudate producing chronic wounds are leg ulcers, diabetic foot ulcers, pressure ulcers, fungating carcinomas, chronically infected wounds, fistulae, deep wounds, and wounds associated with limb and sinus edema. 8 Grade 1 pressure ulcers are non-blanchable erythema of intact skin. Other indicators that are particularly useful in darker skinned individuals are discoloration of the skin, warmth, edema, induration or hardness. Grade 2 pressure ulcers are associated with partial-thickness skin loss involving the epidermis, dermis or both. The ulcer is superficial and presents clinically as an abrasion or a blister. Grade 3 pressure ulcers are those that have full-thickness skin loss involving damage to or necrosis of subcutaneous tissue that may extend down to but not through underlying fascia. Grade 4 pressure ulcers have extensive destruction, tissue necrosis, or damage to muscle, bone, or supporting structures with or without full-thickness skin loss. 9 Arterial ulcers are small in size, about 1-2 cm in diameter, symmetrically round-shaped with a pale, deep wound bed. They have demarcated borders that appear thickened and rolled but have minimal drainage. 9 PharmacyTech.EliteCME.com

5 Venous stasis ulcers Venous stasis ulcers occur in the lower extremities of the body anywhere between the ankle and the midcalf. 9 They arise when the veins of the legs become dilated and the valves cannot function properly. This leads to the congestion of blood, and the fluid leaks from the veins and congests the immediate tissue area. 9 The poorly perfused tissue eventually dies, leading to the formation of an ulcer. A number of factors predispose individuals to venous insufficiency, including: Prior pregnancy. Deep vein thrombosis. Leg trauma. Cardiac disease. Poor nutrition. Poor calf muscle pumps. 9 Diabetic ulcers Diabetic ulcers occur in the bony or pressure-bearing surfaces of the foot (ball, heel and surfaces). Their classification depends upon the depth of the ulcer, the presence of ischemia, and the degree of infection. 9 There are two classification systems currently used to categorize diabetic foot ulcers: The Wagner Ulcer Grade System. The University of Texas Wound Classification System. The Wagner Ulcer Grade Classification System 10 Grade Characteristics 0 Pre-ulcer lesion Healed ulcer bone deformity 1 Superficial ulcer without subcutaneous tissue involvement 2 Penetration through the subcutaneous tissue; may expose the bone, tendon, ligament, or joint capsule 3 Osteitis, abscess or osteomyelitis 4 Gangrene of the digit 5 Gangrene requiring foot amputation Surgical wounds A surgical wound is an intentional wound created by a surgical incision. 9 It is considered acute for the first days, but chronic if it lasts longer. Most surgical wounds are closed with negligible tissue loss. Wound thickness In some situations, classifying the wound based upon the depth of damage may be useful. Superficial wounds are those in which only the epithelial layer of the skin is damaged. The skin has a reddened appearance, might be swollen and feels very sore. Sunburns are a typical example of superficial wounds. 9 Unlike arterial ulcers, venous ulcers have irregular, poorly demarcated borders with moderate to heavy drainage. 9 Because venous ulcers sometimes go as deep as the subcutaneous tissue, they may be very painful. 9 Assessing a patient for a venous ulcer involves obtaining a complete patient history. 9 A physical examination should be conducted to reveal any edema, hemosiderin deposits, dermatitis, positive pules, scarring from previous ulcers and ankle flare. 9 Clinical signs of venous ulcers are: Brown staining seem in the skin above the medial malleolus. Edema. Varicose eczema. Venous ulcers are treated using compression therapy techniques. The University of Texas Wound Classification System 11 Stage Grade 0 Grade 1 Grade 2 Grade 3 A Pre-ulcerative or postulcerative foot at risk for further ulceration Superficial ulcer without tendon, capsule, or bone involvement Ulcer penetrating to tendon or joint capsule Ulcer penetrating to bone B C D infection ischemia infection and ischemia infection ischemia infection and ischemia infection ischemia infection and ischemia infection ischemia infection and ischemia The underlying cause of diabetic foot ulcers is elevated glucose levels from diabetes. The pressure points on the planta r of the foot build up as a callous, creating further pressure. The skin eventually ruptures, leading to an ulcer. 9 Diabetic ulcers tend to be symmetrically round with a heavy periulcer callous and have moderate to heavy drainage. The ulcer contains granular tissue, has a deep wound bed, and is at a high risk of infection. 9 Assessing the diabetic ulcer involves a comprehensive patient history, physical examination, tests to evaluate neurologic function, and tests to evaluate pressure and perfusion of the lower leg and foot. 9 Diabetic foot ulcers need to be properly cleaned and dressed as well as off-loaded. Treatment modalities include topical antimicrobials, debridement, biotherapies and even surgery. 9 The type and frequency of wound care depends upon the location of the incision, the extent of tissue loss and the condition of the surgical wound. Wound healing is monitored from a baseline. Chronic surgical wounds can be closed through primary, secondary or tertiary healing techniques. 9 Partial-thickness wounds are those that are involved with destruction throughout the epidermis into but not through the dermis. Such wounds heal by re-epithelialization. Examples of partial-thickness wounds include stage I and II pressure ulcers, mild abrasions, seconddegree burns and donor sites. 9 PharmacyTech.EliteCME.com Page 13

6 Full-thickness wounds are those that have complete damage through the skin. 9 Tissue destruction extends through the epidermis and the dermis. In some cases, the subcutaneous layer, underlying muscle or connective tissue may be damaged. 9 Full-thickness wounds heal by granulation, contraction and re-epithelialization. Examples of full-thickness wounds include Stage III and IV pressure ulcers, deep surgical incisions, and third-degree burns. 9 Factors that delay wound healing When managing wounds, it is useful to know what factors might delay wound healing and remove these factors, if possible, to accelerate the wound healing process. These factors include: Local factors that impede the healing process, including:9 Pressure: Pressure impedes blood flow to the surrounding tissue and delays healing. Desiccation: Cells in desiccated wounds dehydrate and dry, resulting in slower wound healing. Trauma and edema: Trauma and edema can reduce localized blood supply and hence slow down wound healing. Infections: The presence of an infection means that the wound will remain in the inflammatory phase for longer and hence delay the healing process. Necrosis: Necrotic tissue, both slough and eschar, must be removed before healing can occur. Incontinence: Urinary and fecal incontinence can alter the skin s integrity. Systemic factors that affect the overall body include:9 Age: Elderly patients are at a higher risk for developing problem wounds because of their compromised immune, circulatory and respiratory systems, poor hydration and improper nutrition. Body mass index: Obesity reduces the supply of blood to the adipose tissue and limits people s mobility. Emaciation compromises patients nutritional status and increases the bony prominences. Stress: Hormones, such as steroids, become elevated during periods of stress. To overcome the stress, the body s defenses are diverted to manage the stressful condition, away from the healing process of the wound. Nutrition: The correct levels of total protein, serum albumin and hematocrit are required to facilitate wound healing. Nutritional assessment provides a better insight of patients nutritional status. Medications: Drugs may prevent or slow the healing process. Tissue oxygenation: Tissue hypoxia leads to tissue deterioration and the formation of an ulcer. Concomitant disease: Medical conditions, such as diabetes, can delay the wound healing process. Therapies Patients undergoing radiation therapy or taking steroids are at an increased risk of delayed wound healing. 9 Radiation impairs the cells responsible for collagen production and may actually shrink the numbers of collagen cells, disrupting the wound healing or resulting in a weak wound. Furthermore, radiation can damage blood vessels, reducing tissue perfusion. 9 Wound management products Topical preparations including dressings for wound care have been used for centuries. These play a role in wound management and have developed greatly over the last 50 years from passive to more active types. 12 The first dressings used in the 18th century were made from natural materials, such as oakum. These dressings were absorbent but could not retain the exudate, caused infections, and adhered to the wound bed. 5 This led to the development of Gamgee, an absorbent cotton-wool core sandwiched between two layers of absorbent cotton gauze. 5 In the 19th and 20th centuries, synthetic ingredients were increasingly used in the manufacture of dressings. 6 In modern day medicine, when dispensing a prescription for wound management products, you will come across a variety of items apart from simple dressings. These include: Biologics and biosynthetics, including growth factors. Wound cleansers Before a wound can be dressed, it needs to be thoroughly cleaned. There are various cleaning solutions that can be used to remove any contaminants, foreign debris and wound exudate from the wound surface or to irrigate deep cavity wounds. In rare cases, you may have to prepare a cleaning solution in the pharmacy or advise patients on how to prepare the solution at home. Sterile water: Sterile water is safe to use anywhere on the body. Water can be sterilized by boiling for 60 seconds and allowing it to cool. Sterile water prepared this way must be stored in a closed, Page 14 Corticosteroids suppress inflammation, including the inflammatory phase of wound healing. Patients that cannot be taken off corticosteroid therapy should be prescribed Vitamin A for topical and systemic use to reverse the effects of corticosteroids on wound healing 9. Biophysical agents, such as electrical stimulation therapy and oxygenation. Cellular and tissue-based products for wounds, including both nonviable and viable human and tissue-based products. Compression therapy. Debridement agents. Drainage collectors. Mobility aids. Negative pressure wound therapy. Nutritional management products, including nutritional supplements. Off-loading devices. Positioners and protectors. Tapes and bandages. Wound cleansers. sterile container and refrigerated, if possible. The water is useable for several days. 13 Saline: Safe to use anywhere on the body. Can be made by adding 1 teaspoon of salt to 1 liter of water, boiling for at least 60 seconds and then allowing it to cool. Saline solution prepared this way needs to be stored in a closed, sterile container and refrigerated if possible. The solution is useable for several days. 13 Povidone-iodine: Povidone iodine should be used diluted in the ratio of 1:4 in water because it is toxic to healthy tissues. 13 PharmacyTech.EliteCME.com

7 Dakin s solution: Dakin s solution is a mixture of ml of liquid bleach in 1 liter of saline solution. This mixture is best used further diluted in saline in a ratio of 1:4. Dakin s solution is a better antibacterial than saline and therefore, slightly harsher on Dressings 4,14 15 An ideal dressing should: Maintain a moist environment. Provide thermal insulation. Be nonadherent. Require infrequent changing. Provide mechanical protection. Be free from particulate contaminants. Be safe to use (i.e., non-toxic, non-allergenic). Be conformable, moldable, and comfortable. Have good absorption characteristics. Be impermeable to microorganisms. Be acceptable to the patient. Be cost effective. Be sterile. Be available in a suitable range of forms and sizes. Presently, there are more than 20 different categories of wound treatment products, including cleansers, debriders, dressings and fillers. Others include: Alginates. Collagens. Composites. Contact layers. Foams. Hydrocolloids. Hydrogels. Specialty. Wound fillers. Transparent films. The product selection is based upon both the patient and wound characteristics. Patient characteristics include: Endocrine disease, e.g., diabetes, hypothyroidism. Hematologic conditions, e.g., anemia, polycythemia, myeloproliferative disorders. Cardiopulmonary problems, e.g., chronic obstructive pulmonary disease. Gastrointestinal problems that may cause malnutrition and vitamin deficiencies. Obesity. Peripheral vascular pathology, e.g., atherosclerotic disease, chronic venous insufficiency, lymphedema. Autoimmune disorders. Alginates Alginates are made of soft, nonwoven fibers derived from brown seaweed extract. They are usually supplied in the forms of pads, ropes or ribbons. 6, 14 The calcium salts of alginic, mannuronic, or gularonic acids are processed to form the fibers. When these fibers come into contact with fluid rich in sodium such as that in wound exudates, the calcium ions undergo a transaction that results in the formation of a soluble sodium gel. Depending upon the type of seaweed used, some alginate dressings may swell in the wound rather than gelling. 7 Alginates do not physically inhibit wound contraction. 6 Alginates are highly absorbent and useful for wounds that have copious amounts of exudates because they can absorb up to 20 times their own weight in fluid. They are not recommended for wounds with light exudates or dry eschar. Alginate rope is particularly useful normal tissues. It also reduces odor in wounds. Dakin s solution should not be used around the eyes. 13 Commercially available preparations include 3M Wound Cleanser, Amerigel wound wash, and Dermagran wound cleanser. Wound characteristics include: Location. Stage. Size and depth of involvement. Extent of undermining. Absence or presence of sinus tracts. Appearance of the wound surface. Amount and characteristic of wound exudate. Status of the periwound tissues. amount and type of bioburden. Absence or presence of epithelialization and granulation tissue. Host response to previous treatments. The aim of the wound treatment should be to decrease the local bioburden and facilitate healing. This can be achieved through adequate oxygenation, debridement of nonvitalized tissue, removal of debris and exudates, and provision of a moist, but not wet, wound bed. Therapy should be aimed at not only healing the wound by preventing complications but also at minimizing scarring and disability. Patient factors to be taken into consideration when selecting therapy include patient comfort, odor control, costs, and individual preferences. Underlying conditions, such as malnutrition, anemia, diabetes, and obesity, and cardiopulmonary, gastrointestinal and immunologic disorders, need to be taken into account when selecting a treatment option. Wound dressings can be divided according to the effect they have on the moisture in the wound bed as follows: Absorb moisture Neutral Add moisture Alginates Composites Sheet hydrogels Specialty absorptives Mini-VAC devices Amorphous hydrogels VAC devices Transparent films Debriding agents Gauze Biological dressings Foam Collagen dressings Hydrocolloids Contact layers Compression dressings Wound fillers Warm-up therapy systems Primary dressings cover the wound directly, whereas secondary dressings are used to hold a primary dressing in place. to pack exudative wound cavities or sinus tracts. They should not be used in burns. In some cases, alginates can also be used to provide hemostasis as the alginate stops bleeding after ion exchange with the wound bed, the wound fluid and the dressing. Most alginates absorb many times their own weight. The dry dressing is extremely lightweight and easy to apply. These dressings require a secondary dressing to secure them in place and may leave fibers in the wound if irrigation is not adequately performed. Caution should be used because the pooling exudate from alginate dressings may cause maceration of the surrounding tissues. Care should be taken to leave room for expansion when packing cavities. 16 They should not be used with hydrogels that will add fluid to the alginate and reduce its fluid handling capacity. 4 PharmacyTech.EliteCME.com Page 15

8 Most alginates last three days, although some can last as long as seven days. When removing an alginate dressing, ensure that all of the used dressing is removed because it can form a crust around the wound. Case study Mrs. Y. is a regular customer at your pharmacy. Her daughter brings in a prescription for a Sorbsan dressing and 500 ml of normal saline. Unfortunately, you have run out of normal saline but are expecting the next delivery within two days. Mrs. Y. s daughter starts to panic. When you ask her whether the wound has been cleaned, she explains that the nurse came with one bottle of normal saline, which she used to clean the wound. She is not sure why she requires more normal saline. Charcoal dressings Some wounds, such as leg ulcers and fungating (cancerous) lesions, may become malodorous from the metabolic processes of bacteria within the wound. Charcoal dressings absorb the molecules released from the wound that may be responsible for the odor. Organisms Collagens Collagen is a natural biomaterial that plays an integral part in each phase of wound healing. Collagen dressings are derived from porcine, avian, and bovine tendon. Placing collagen on the wound activates inflammatory cells, including fibroblastic growth, and promotes increased vascularization of the healing tissue. Collagen dressings are suitable for moderate to heavily draining wounds to enhance healing and tissue repair. They are indicated for Composite treatments Composite treatments combine more than one component into a single dressing, for example, an antimicrobial and an absorbent pad. 9 They are useful for a broad range of wound types, including those with minimal or heavy exudates, partial- and full-thickness wounds, and those with granulation and necrotic tissue. 9 These dressing are particularly useful in outpatient settings and for home use. They are most widely seen in the delivery of topical antimicrobials, such as silver and iodine. 9 Composite dressings are easy to use, maintain hydration, treat bioburden and have the potential of reducing the frequency of dressing Contact layers Contact layers are thin, nonadherent sheets placed directly on an open wound bed to protect the wound tissue from direct contact with other agents or dressings applied to the wound. They are porous, allowing the fluid to pass through for absorption by an overlaid dressing. 9 Contact layer dressings are best for partial- to full-thickness wounds, infected wounds, donor sites and split-thickness skin grafts. They may be used with topical medicated preparations. 9 Foams Foam dressings are highly absorbent dressings usually made from a hydrophobic polyurethane foam or silicone foam, and generally have a waterproof backing. 17 They have various absorption rates, and some foam products also come with adhesive tapes surrounding an island of foam. They are useful for heavily exudating wounds, particularly during the inflammatory phase following debridement and desloughing, when drainage is at its peak. 17 They are also effective for packing deep cavity wounds to prevent premature closure while absorbing exudate and maintaining a moist environment, and in Some brands can be removed as one sheet after moistening with normal saline, while others may need irrigation with normal saline to flush out the old dressing. From this information, you gather that the normal saline is not required for wound cleaning, but rather for removing the dressing three days later. You therefore have time to order and dispense the normal saline. Upon calling the nurse, you discover that this is in fact the case, and that Mrs. Y. s daughter can come for the normal saline in a couple of days. frequently isolated from malodorous wounds include anaerobes such as Bacteroides and Clostridium species, and aerobic bacteria including Proteus, Klebsiella and Pseudomonas spp. partial- and full-thickness pressure ulcers, venous ulcers, donor sites, surgical wounds, vascular ulcers, diabetic foot ulcers, second-degree burns, abrasions, traumatic wounds and cuts. Collagen is an excellent hemostatic agent that can absorb times its weight in fluid. Because a secondary dressing is required to keep collagen dressings in place, they are not recommended for use in wounds with eschar. When combined with other dressings, they may have an advantageous effect on growth-stalling matrix metalloproteinases. changes. 9 They are, however, costly and may promote prolonged moisture contact with the surrounding intact skin. 9 Dressings impregnated with antibacterials, such as silver or iodine, are targeted at preventing infections. 9 Additionally, topical bacitracin, polymyxin B, neomycin and their compound forms may be formulated into an ointment. 9 These are soothing, comfortable to wear, lubricating, occlusive and deliver the antibiotic directly to the wound. They are effective in limiting scab formation. Because contact layer dressings provide physical separation between the wound and the external environments, they aid in the creation of a moist wound environment and prevent bacterial contamination. Contact layers require the use of a secondary dressing and are therefore not recommended for shallow or dehydrated wounds or wounds covered with eschar. 9 weeping ulcers, such as venous stasis. 19 The correct size of a foam dressing is one that overlaps the wound edges from 2-5 cm. Foam dressings rarely adhere to the wound bed and are very comfortable to wear. They can be worn during bathing and can frequently be left undisturbed for three to four days. 17 Foams that absorb exudate will decrease maceration to the surrounding tissue but can cause a drying effect on the wound if there is too little drainage. Page 16 PharmacyTech.EliteCME.com

9 Gauze products Gauze and nonwoven wound dressings are dry woven or nonwoven sponges and wraps. These products vary in the degree of absorbency, and are available as sterile or nonsterile and with or without adhesive borders. 9 Honey-based dressing Honey has been used for the treatment of acute and chronic wounds for centuries for its antimicrobial properties. Furthermore, honey reduces edema, lowers wound ph, and debrides slough and eschar. The honey used today in wound preparations has to be carefully selected because not all types of honey are suitable. 19 Manuka honey from New Zealand is considered to be most appropriate for wound care. It absorbs exudate and has antibiotic properties. 19 To achieve medical grade honey, it has to be filtered, gammairradiated, and produced under controlled standards of hygiene to ensure standardization. It can be used on its own or added to other dressings, including alginates and synthetic mesh. 19 Honey is indicated Hydrocolloids or hydrofibers These occlusive and adhesive wafer dressing, also referred to as hydrofibers, are made of a microgranular suspension of natural or synthetic polymers, such as gelatin, carboxymethyl cellulose, or pectin, in an adhesive matrix. Most hydrocolloids react with the wound exudate to form a gel-like covering that protects the wound bed and maintains a moist wound environment. In this way, they promote debridement of necrotic tissue. 17 Hydrocolloids are available in sheets, pastes and powders. Hydrocolloid wound dressings are best for granulating and epithelializing wounds with low-to-moderate amounts of exudate. 17,20 They should not be used for dry wounds or exposed bone or muscle. Because they are occlusive, patients can shower while wearing a hydrocolloid dressing, however their occlusive properties may cause them to promote overgrowth of anaerobic bacteria, and therefore, they are contraindicated for infected wounds. 21 Hydrogels Hydrogels consist of a matrix of insoluble hydrophilic polymers that swell in water but do not themselves dissolve. They contain about 60 percent to 90 percent water and are available as gels, sheets, and impregnated nonwoven dressings. Hydrogel wound dressings are effective, comfortable, easy to use, and cost effective. Some hydrogel sheets have an adhesive border, but most require a secondary dressing. Hydrogels keep the wound surface moist as long as it is not allowed to dehydrate. Hydrogels are useful for wounds with minimal or no exudate, painful wounds, burns, and skin tears because they hydrate the wound surface and in some cases, absorb excess exudate. 17, 22 They are primarily rehydrating, although some can absorb excess exudate. This ability Iodine-based dressings Iodine is a traditionally used antiseptic that is found in several different formats. Dressings that are impregnated with cadexomer-iodine are absorbent and promote debridement as well as having an antimicrobial effect. These dressings are suitable for infected necrotic wounds. 9 Dressings with povidone-iodine are low adherents, nonabsorbent and mainly used on minor traumatic injuries, including cuts and grazes. 9 Since the absorption of large amounts of iodine by the thyroid gland Gauze swabs are widely used in wound care both as primary and secondary dressings. Gauze swabs stick to wounds and can be painful to remove at the same time, damaging any newly regenerated tissue. They are not very absorbent, and exudate can easily soak through them, allowing the movement of bacteria through the wound. 9 for pressure ulcers, leg ulcers, burns, donor sites of skin grafts and surgical wounds. 19 Honey is very sticky and requires careful application it is either poured onto the wound bed or applied via a honey-saturated substrate. 19 These techniques are cumbersome, wasteful and messy. Furthermore, the viscosity of the honey increases with an increase in temperatures and liquefies at body temperatures. Honey dressings should not be used in diabetic patients because honey may result in hyperglycemia. 19 The drawing sensation produced by honey may be discomforting. The sheets are conformable, with easy application, and help reduce pain at the wound site; shaped sheets are available for awkward areas, such as the heels and elbow.17 Pastes and powders tend to have a greater absorptive capacity than the sheets and are usually used to fill cavity wounds to the surface. 4 These dressings break down to produce residue of various colors and a foul odor that may sometimes be mistaken for an infection. Hydrocolloids containing gelatin from pigs may not be acceptable in patients of some religious backgrounds and vegetarians. The frequency of changing the sheets depends upon the level of exudate, and is usually between five to seven days. Because of this long wear time and the opaque nature of the dressing, patients often become concerned about infected wounds. allows desloughing and debriding capacities to necrotic and fibrotic tissue. They are soothing, cooling, and may even reduce pain, and therefore are particularly useful when applied to radiation burns. 4 On the downside, the high water content of hydrogels may lead to maceration around the wound area. It is therefore important that no more than the required amount of dressings be applied to the wound. 4 Hydrogels contain propylene glycol, a chemical that is contraindicated before larvae therapy. Wounds that are to be treated using larval therapy should therefore be free of hydrogels and thoroughly irrigated 24 hours before therapy. Hydrogel dressings are changed between one to three times a week. 17 can be harmful, the long-term use of iodine dressings is not advisable. Furthermore, the systemic absorption of iodine can cause an allergic response. 9 PharmacyTech.EliteCME.com Page 17

10 Silicone dressings Silicone dressings are made of soft polymers with a slightly tacky wound contact layer. As such, they can be removed without causing any trauma to the wound or surrounding skin. 9 Silicon dressings Silver dressings Silver has antimicrobial properties that can be added to dressings. Silver sulphadiazine is useful as a cream for the management of burns. Silver has also been shown to be effective in treating wounds that are infected with methicillin-resistant Staphylococcus aureus (MRSA). Silver may be added to alginate, hydrofiber, hydrocolloid, foam, and activated charcoal dressings. 23 Silver exerts its antibacterial effects in a number of ways: 14 Interferes with bacterial electron transport. Binds to DNA of bacteria and their spores, increasing the stability of the double helix and impairing replication. Interacts with the bacterial cell membrane and damages the structure. Forms insoluble, metabolically ineffective compounds. Specialty absorptives This is a broad range of composite products that have a capillary action that wicks away mild, moderate, or heavy drainage from wounds. These type of dressings help prevent the periwound area from becoming macerated. 15 They include pads containing nonadherent contact layers with highly absorbent layers of fibers (cellulose, cotton, or rayon) that gel upon contact with the drainage. Transparent films Transparent adhesive film dressings are made of polyurethane and are semi-permeable membrane dressings that are waterproof yet permeable to oxygen and water vapor. 15 They maintain a moist wound environment and help prevent bacterial contamination. 15,17 These films facilitate cellular migration and promote autolysis of necrotic tissue by trapping moisture at the wound surface. 15 Film dressings are best for superficial wounds; wounds with light exudate; wounds on the elbows, heels, or flat surfaces; covering blisters; and for the retention of primary dressing, especially hydrocolloid and alginates, because they provide waterproof cover. 16 Wound fillers Wound fillers including pastes, powders, beads, gels, foams, pillows, strands and other formulation of substances, are designed to fill cavities and manage wound drainage. 9 They maintain a moist environment and may contain antibacterials impregnated in them. 9 Wound fillers are the perfect choice of dressing for partial- or fullthickness wounds when used alongside foams, hydrocolloids and composites to increase the absorption of wound drainage. 9 The use of wound fillers in dry wounds or sinus tracts is not recommended. Wound fillers obliterate dead space, absorb exudate, retain moisture, and promote autolytic debridement. However, the application of wound fillers needs some experience, and some dressings may even require reconstitution with saline or sterile water for application. 9 An example of wound fillers is polysaccharide bead dressings, which are made of hydrophilic, biodegradable, sterile dextranomer beads may be combined to form silicone layer dressings with a variety of backings, which impact the level of absorbency. 9 It is important that the minimum effective amount of silver is applied to reduce systemic absorption, because silver may be toxic. 14 Some patients may find the gray discoloration, formed when the silver reacts with pollutants in the environment to form silver sulphide, unpleasant. 14 Silver dressings are used for two weeks and then the wound is reassessed. They should not be used in patients receiving radiotherapy, x-rays, ultrasound, and diathermy. 23 Because silver is inactivated by protein binding, dressings that release silver slowly need to be changed less frequently than those that immediately release silver. 12 Specialty absorptives are best on wounds that have a heavy discharge. They may be used as primary or secondary dressings. Those without an adhesive border are usually changed once daily, whereas those with an adhesive border may be changed every other day. 15 An appropriate film dressing is one that allows for a 4-5 cm overlap onto the surrounding skin. Film dressings cannot be used for wounds with moderate-to-heavy exudate and must be selected carefully, because some newer films are intended for IV sites and may dry up the wound. 17 They are usually changed up to three times per week. 17 Transparent films permit evaluation of the wound progress without having to remove the product. They are usually waterproof, gas permeable, economical, and help maintain a moist wound environment. As an adhesive, transparent films have the potential of causing skin tears if not correctly removed. mixed with glycol and water to form a paste. 9 They are also available in a pad form, and may contain antiseptics such as iodine. 9 Bead dressings can absorb up to seven times their weight in fluid through capillary action, which helps to remove slough and hold bacteria from the wound bed. Beads containing iodine slowly release this antimicrobial as they swell. 9 Dressings should be changed frequently when the iodine loses color. This indicates saturation with exudate. 9 The beads can cause discomfort when applied to clean, granulating wounds, and they must be used in conjunction with a secondary dressing. Beads containing iodine may cause allergic reactions to iodine and may affect the thyroid if too much iodine is absorbed. 9 Methods of dressing retention Once a dressing is applied, it needs to be held in place using either surgical tapes or bandages, which are the main methods of retaining dressings. 9 Page 18 PharmacyTech.EliteCME.com