1、10/14/2018,1,Sutures & Wound Dressings,10/14/2018,2,Wound Care and Management,More than a million Americans suffer from non-healing wounds annually, at a cost of $750 million; Etiology: trauma, inactivity, disease and surgery; 3,852 wound care products on the market; Some classified as drugs or biol
2、ogics, while others are classified as devices;,10/14/2018,3,Wound Care Products,Goals: Bind surface epithelium and underlying connective tissues when possible; Protect wound from infection; Maintain moist wound environment; Permit gas exchange; and, Promote rapid epithelialization.,10/14/2018,4,Prin
3、ciples of Wound Healing,Hemostasis Inflammation Granulation Tissue Tissue remodeling or maturation,10/14/2018,5,Keys to Wound Care,Identify the causative factors Improve the local environment,10/14/2018,6,Common Underlying Causes of Wounds,Trauma-accident or intentional (surgery) Scalds and burns (c
4、hemical and physical) Animal bites or insect stings Pressure (spinal injured) Vasculature related, arterial, venous, mixed Immunodeficiency Malignancy Connective tissue disorders Metablolic or endocrine disorders (diabetes) Nutritional deficiencies Psycho social Adverse effects of medications,10/14/
5、2018,7,Timetable of Wound Healing,Hemostasis immediate Inflammation 1-4 days Granulation Tissue 4-21 days Tissue remodeling 21 days-2 yearsor maturation,10/14/2018,8,10/14/2018,9,Wound Color,Black. Necrotic tissue is non-viable, and it must be removed before healing can take place.,Yellow. Yellow wo
6、unds may contain moist necrotic tissue (slough) and/or contain purulent drainage. The primary objective is to remove unhealthy tissue, any contaminants, debris and excess exudate which deter the healing process. Once a clean, moist and viable wound bed is achieved, healing can begin.,Red. Is good-th
7、e actively healing phase of a wound, cells proliferate, fibroblasts form collagen and eventually small, red, fleshy masses called granulation tissue (angiogenesis) begin to form.,10/14/2018,10,History of Biomaterials in Medicine,Ancient cultures used primitive materials from their natural surroundin
8、gs to heal their wounds and to cure diseases. The oldest known use of bandages -Sumeria (2100 BC). a medical manuscript written on stone tablets describes detailed procedures of washing wounds, making plaster, and bandaging.,10/14/2018,11,“Early Wound Dressing”,Natural adhesive bandages were used 4,
9、000 years ago by the Egyptians. In the Edwin Smith papyrus, Egyptians wrote of using woven bandages soaked in a quick setting plasters used as adhesive tapes were discussed in the manuscript. The oldest bandages that have been found were in the tombs of the Pharaohs.,10/14/2018,12,Sutures,Used as th
10、e means of repairing damaged tissues, cut vessels, and surgical incisions- Initially a variety of natural materials were used: flax, hair, linen strips, pig bristles, grasses, mandibles of pincher ants, cotton, silk, and the gut of an animal,10/14/2018,13,Sutures,The largest group of devices implant
11、ed in humans; By definition, a suture is a filament that either approximates or maintains tissues in juxtaposition until the natural healing process has provided a sufficient level of wound strength or compresses blood vessels in order to stop bleeding; Classified into one of two groups, absorbable
12、and nonabsorbable;,10/14/2018,14,Commercially Available Sutures,cellulose based (cotton) protein-cellulose (silk) processed collagen (catgut) nylon Polypropylene Aramid Alha-hydroxy acids polyglycologic acid polyglycolide-lactide polymer polytetraflourethylene Stainless steel aluminum alloys,10/14/2
13、018,15,Test Specifcation for Sutures,breaking strength elongation-to-break Youngs modulus knot security viscoelastic properties tissue reaction cellular response cellular enzyme activity suture metabolism chronic toxicity teratologics mutagenicity carcinogenicity allergenicity Immunigenicity,10/14/2
14、018,16,Suture Size,10/14/2018,17,Staples,Thin metal used to approximate the edges of the skin (area must be anesthetized); Staple appliers push the two prongs of the staple down through the epidermis and dermis into the subdermal layer and then bend these prongs inward; Once these prongs have been b
15、ent inwards, the positions of the skin edges are fixed; The major advantages are speed of closure and less scarring. Indicated on scalp and abdomen (tendons, nerves deep),10/14/2018,18,Stapling a Craniotomy Skin Incision,10/14/2018,19,Staples,10/14/2018,20,Staple Considerations,If the edges are not
16、lined up flush, misalignment will be maintained during the healing process and may impede the formation a skin layer across the skin surface or result in excessive scar tissue formation.,10/14/2018,21,Removal,removed by your health care provider 3 to 14 days after they are put in.,10/14/2018,22,Mate
17、rials Used for Hemostais,Surgical cellulose is a material that is comes in thin sheets of interwoven specially treated cellulose that provides a matrix to which platelets and clotting factors can adhere leading to formation on the cellulose of a dense clot which can act as a patch over an area of bl
18、eeding.,10/14/2018,23,Tissue Adhesive,Indicated for the closure of topical skin incisions including laparoscopic incisions, and trauma-induced lacerations in areas of low skin tension that are simple, thoroughly-cleansed, and have easily approximated skin edges. INDERMILTM Tissue Adhesive Receives F
19、DA Approval for Closure of Topical Skin Incisions and Lacerations Indermil may be used in conjunction with, but not in place of, deep dermal stitches.,10/14/2018,24,Device Description,Tissue adhesives are sterile, liquid topical composed of n-Butyl or octyl-2-Cyanoacrylate monomer supplied in a 0.5g
20、 single patient use, plastic ampule. Each ampule is sealed within a foil packet so the exterior of the ampule is also sterile. Remains liquid until exposed to water or water-containing substances / tissue, after which it cures (polymerizes) and forms a film that bonds to the underlying surface.,10/1
21、4/2018,25,Traditional Wound Care Products,Protective and gas permeable Transparent Films Foams Hydrocolloids or Hydrogels Alginates Specialty Absorptive Dressings,10/14/2018,26,Transparent Films,Acu-derm Bioclusive Blisterfilm Polyskin II Pro-Clude Op-Site Opraflex Tegaderm Transeal Transite Uniflex
22、 Ventex,10/14/2018,27,Infection Control Products -Dressings to Secure Catheters,a thin, semi-occlusive, transparent polyurethane film dressing that provides a bacterial/viral barrier and helps secure catheters, reducing mechanical irritation.,10/14/2018,28,Transparent Films,Advantages: Waterproof an
23、d Bacteria-proof Allows visualization of the wound. Wont traumatize wound when removed. Disadvantages Not rec. for wound with moderate/heavy exudate. Not rec. for wound with fragile surrounding skin. Provides no cushioning to wound.,10/14/2018,29,Foams,Examples Allevyn Cutinova Foam Epilock Flexzam
24、Hydrasorb Lyofoam Mitraflex Nu-derm Polymem Tielle,10/14/2018,30,Foams-polyurethane pads,-Indications: Noninfected, draining granular wound Advantages Non-adherent Wont injure surrounding skin Can repel contaminants May be used under compression Cushions wound surface Maintains moist wound evironmen
25、t Highly conforming Gas permeable,10/14/2018,31,Hydrocolloids,in pad,sheet or filler form for occlusive use. Forms a “gel” as it absorbs water from the wound bed that sits on wound Indications: Small, solitary non-draining ulcers or light-to-moderate exudate wounds Advantages Impermeable to bacteria
26、 and other contaminants Promotes autolysis, angiogenesis, and granulation Self-adhesive and molds well Limited-to-moderate absorption Creates moist environment May be left in place for up to 5 days May be worn in the shower,10/14/2018,32,Hydrocolloids,AquaCel Comfeel Cutinova Hydra Duoderm Hydrapad
27、Intrasite J&J Ulcer Dressing Procol Replicare Restore Triad Ultec,10/14/2018,33,Hydrogels,-cross-linked hydrophilic matrix impregnated into gauze-type pads which allows transmission of water, vapor and CO2 but discourages dehydration. Indications: full thickness wounds with moderate drainage Soothin
28、g and conforms to wound Fills in dead spaces Highly absorptive Can be used on infected wounds Disadvantages Difficult to keep in place Encourages gram negative organisms,10/14/2018,34,Hydrogels,AquaSorb Carrington Gel Carrasyn-V Clear-Site Curasol Gel Flexderm Hydron Intrasite Gel Solosite SAF-Gel T
29、ransorb WounDres,10/14/2018,35,Adhesive Gel Sheets for Scar Treatment,Flexible, adhesive, semi-occlusive silicone gel sheet. Reduces raised scars and redness of the scar so it fades and becomes less noticeable. Self-adhesiveness and durability mean that application is simple and the gel sheet can be
30、 washed and used several times.,10/14/2018,36,Resorbing Matrices,Matrix is a primary dressing which transforms into a soft, conformable gel, allowing contact with the entire wound bed; Consists of 45% regenerating cellulose and 55% type I collagen,10/14/2018,37,Resorbing Matrices,The persisting infl
31、ammatory phase in chronic wounds contributes to exudate with high concentrations of matrix metalloproteases (MMPs); Excess MMPs result in degradation of extracellular matrix proteins; Excess MMPs inactivate growth factors; cellulose/collagen combination binds more MMPs than ORC or collagen alone,10/
32、14/2018,38,Apligraf human skin-like products comprised of living human skin cells,Organogenesis,10/14/2018,39,Living Skin Equivalents,Living bi-layered skin substitutes Apligraf (formerly Graftskin) Type I bovine collagen, extracted and purified from bovine tendons, and viable allogenic human fibrob
33、last and keratinocyte cells. Dermagraft Human neonatal fibroblasts derived from fetal foreskin, extracellular matrix and a bioabsorbable suture like scaffold.,10/14/2018,40,Indications: diabetic foot ulcer care of full-thickness ulcers of neuropathic etiology of at lease three weeks duration and burns Contraindications:-infections-exposed bone, capsule, muscle or tendon,Living Skin Equivalents,
