But not displaced by new moist wound dressings, one would think that for so many new choices for wound care that a variety would expect to find a variety of dressing products in use among wound care patients. Despite the benefits of new dressings gauze is still the most widely used in wound care. In late 90 13 home agencies in one geographic area gathered info for 1 week regarding the types of dressing used forr 1029 patients with 1638 classidied wounds-the majority were dry gauze 406, 3 rd most use sale moistened with (145) 2 nd no dressing at all252advanced moisture retentive dressings accounted for less than 25%
So let’s start with most clinicians consider the standard of care for wound care and work from there as look to other treqtment modaliteies.. Which is quaze.. In a study conducted in need updated from 1999But not displaced by new moist wound dressings, one would think that for so many new choices for wound care that a variety would expect to find a variety of dressing products in use among wound care patients. Despite the benefits of new dressings gauze is still the most widely used in wound care. In late 90 13 home agencies in one geographic area gathered info for 1 week regarding the types of dressing used forr 1029 patients with 1638 classidied wounds-the majority were dry gauze 406, 3 rd most use sale moistened with (145) 2 nd no dressing at all252advanced moisture retentive dressings accounted for less than 25%
Non-selective means that both non-viable and viable tissue may be removed There is now a general consensus in the wound community that wet-to-dry dressings are very problematic. As you can see, the AHRQ states that a wet-to-dry dressing implies that it is applied moist and removed when dry. This is very problematic for many reasons, not the lesat of which is that it is non-selective – no control over removal of healthy or necrotic tissue. Above information from reference (Lawrence/Lancet. 1992;339(8796):807) (Sussman/Bates-Jensen)
Drying gauze has a cooling effect on tissue Gauze: 77-81 degrees in wound bed Films/foams: 91-95 degrees in wound bed vasoconstriction and hypoxia, impairment of leukocyte mobility and phagocytic efficiencyIn an open wound with nothing to impede fluid evaporation, the tissue temperature has been measured at 21°C. A gauze dressing placed in the wound does little to impede fluid evaporation and tissue temperature measures 25°C to 27°C—still approximately 10° below normal tissue temperature (Thomas, 1990). All impede wound healing and increase susceptibility to infection Gauze dressings present no physical barrier to the entry of exogenous bacteria. In one dramatic in vitro study it was shown that bacteria were capable of penetrating up to 64 layers of dry gauze (Lawrence, 1994). Moistened gauze presents even less of a barrier to bacterial penetration.
Probably more of an issue in home environment where infection control is not rigorously practiced
Colwell et al
Appropriate topical therapy may only be successful after removal if causative factors (eg., pressure, shear, poor vascularity) and assurance of sufficient systemic support for wound healing. (Emory University - principles)
Regardless of the wound condition, these principles of wound management should always be taken into consideration. It is not possible for one dressing to satisfy all the varying conditions which will occur during the healing process. Choose a dressing that protects the peri-wound skin. What is "MVTR"? MVTR stands for "Moisture Vapor Transmission Rate", a measure of the passage of gaseous H 2 O through a barrier. It's also know as "WVTR", or "Water Vapor Transmission Rate". How is moisture resistance measured? Moisture resistance is measured in a special chamber where it is divided vertically by the substrate/barrier material. A dry atmosphere is in one chamber, and a moist atmosphere is in the other. A 24-hour test is run to see how much moisture passes through the substrate/barrier from the "wet" chamber to the "dry" chamber. Standard test procedures (TAPPI T-464, ASTM E96) can specify any one of five combinations of temperature and humidity in the "wet" chamber. The toughest conditions are 100°F / 95%RH (Relative Humidity). 35
When health care providers are seeking the “ideal dressing”, the following questions should be considered: - Does the dressing protect from secondary infection? - Does it provide a moist wound environment? - Does it provide thermal insulation? - Can it be removed without causing trauma to the skin? - Does the dressing remove/absorb drainage and debris? - Is it free from particulates and toxic products?
Chemical Debridement (Enzymatic) Process of debridement by the use of enzymes. The enzymes break down and digest necrotic tissue by interacting with proteins. • Recommended for moist necrotic tissue (slough) and hard necrosis. • If used on dry eschar, the eschar should be cross-hatched with a scapel and a moisture retentive dressing used (e.g. Film). • Specific to specific tissue such as elastin, fibrin, or denatured collagen; Therefore, a physicians order is required to specify which type. • May cause a transient redness and maceration to the surrounding skin.
Take home message: The amount of silver in a dressing does not make it more effective. The solubility of the compound (how well it can deliver Ag+) is what makes a product function best!!
1. Cell wall rupture When Ag+ binds to proteins in the cell wall, the wall might break and the contents of the call leak out, resulting in death of the bacterial cell. 2. Preventing “eating and breathing” Ag+ might also bind to bacterial enzymes, resulting in the inability of the bacterial cell to carry out processes necessary for respiration or to take in or process nutrients. 3. Disturbing replication Ag+ might also bind to bacterial cell DNA and interfere with cell division and the replication process
p.88 NPUAP/EPUAP guidelines
Supposed to stimulate healing Come in all form and need secodary- gels, pads, sheets, powder
Typically non adhesive primary formulation of collagen selected is based on wound size, vol of exudate Dry minmal- gel with appropriate dressing applied
Wound Care: From then to now
Wound Care:From then to now
Objectives Discuss changes in theories of treatment in wound care and implications to current wound care practice. Review good wound care practice and implications as related to regulatory changes. Review types of wound debridement. Discuss list indications and contraindications for wound dressings.
Evolution of wound care dressings… 1948: “Experiments with occlusive dressings of a new plastic” by JP Bull Discussed properties of a nylon derivative film Water vapor permeability made it suitable for wound dressings Also noted that the presence of a variety of organisms was reduced or disappeared
Evolution of wound care dressings… 1963 (Hinman): “Effects of air exposure and occlusion of experimental human skin wounds” Useda sterile polyethylene film in artificially made wounds on health adult male volunteers Wounds were either occluded or allowed to heal open to air Results:Wounds healing under moist conditions healed 50% faster than wounds open to air Winters, CD Nature 1962
Where we’re going…Traditional dressings:• Gauze, lint and fiber products• Hydrocolloids Look how far we’ve come!!!
Disadvantages of wet to dry: AHRQ Pressure Ulcer Guidelines Wet-to-dry implies gauze is applied moist and removed when dry.Problems? W/D gauze dressings as a form of mechanical debridement are “non-selective” and, …are rarely applied correctly …may cause pain on removal …may be more costly in terms of labor and supplies …may cause maceration of skin surrounding the wound …may release airborne organisms (cross contamination)
What else??? Moistening gauze that is adhered Primary objective is lost Gauze fibers can be left in wound Moist wound healing is an industry standard: known to improve healing rate Winter’s research (1960’s) • Moist wounds healed 2x as fast as wounds allowed to dry
What else??? Inconsistency with application Moisture levels vary with clinicians Wet to moist may dry out and become wet to dry Drying gauze has a cooling effect on tissue Gauze: 77-81 degrees in wound bed Films/foams: 91-95 degrees in wound bed vasoconstriction, hypoxia, impairment of phagocytic efficiencyOvington, L Hanging Wet to Dry Out to Dry. Home HelathCare Nurse. 2001; 19(8), 477-483
There’s more? Gauze dressings present no bacterial barrier Lawrence (1994): 64 layers of dry gauze allowed bacterial penetration Hutchison (1989,1993): Moistened gauze presents less barrier Hutchison (1990): Review of 3047 wounds showed the following infection rate: • 2.6% for those dressed with moisture- retentive dressings • 7.1% for those dressed with gauzeOvington, L Hanging Wet to Dry Out to Dry. Home HelathCare Nurse. 2001; 19(8), 477-483
Cost of Wound Care Cost of dry gauze and ancillary supplies $.47 per dressing change Cost of hydrocolloid and ancillary supplies $6.15 per dressing change Daily Cost (dressing cost + clinician cost) Dry gauze $12.26 Hydrocolloid $3.55
How should we select dressings? Autolytic Fillers PrimaryHydrating Non-adhesive Active Absorbing Secondary Enzymatic
Wound Management Priorities Reduce or eliminate causative factors Provide systemic support for healing Apply appropriate topical therapy Debride - remove necrotic tissue Identify and eliminate infection Fill dead space - lightly Absorb excess exudate Maintain moist wound surface Open closed wound edges Protect from trauma and pain Insulate
Selecting Dressings○ Keeps the wound bed moist ○ Prevents both maceration & desiccation ○ Offers good Moisture Vapor Transmission Rate○ Minimizes peri-wound maceration○ Protects the peri-wound skin○ Eliminates dead space○ Assures packing will stay in place○ Minimizes pain○ Assures stable environment○ Provides thermal insulation○ Always consider caregiver time
Ideal Primary DressingsNeed to be compatible with the wound: May be hydrating or absorptive Promote/maintain moist, healing environment Provide for “breathability” (MVTR) Provide insulation Impermeable to microrganisms minimize contamination from outside Atraumatic to the wound/periwound area Cost effective
Ideal Secondary DressingsNeed to be compatible with the wound: Absorb exudate Provide moisture to wound Promote autolysis (debridement) May be used in infected wounds Be atraumatic to wound/periwound Minimize adherence Minimize movement Minimize stripping Cost effective
Foams Benefits: Bordered and un-bordered Provide a moist environment High absorbency Conformable, may be cut to size Thermal insulation No residue MVTR No adherence to wound bed
Foams Indications: Superficial and full thickness wounds Skin grafts, donor sites, burns, skin tears Under compression for LE ulcers Contraindications: Dry wounds Examples: Mepilex (Border), Allevyn (Plus Adhesive), Polymem, Biatain
Films Benefits: Provide a moist environment Enable autolytic debridement Provide protection from extraneous forces (microbes, friction, shear, chemicals) High MVTR Conformable
Films Indications: Minor injuries (abrasions) Post-op dressing over sutures IV sites Contraindications: High exudate wounds Fragile skin Examples: Tegaderm, Opsite
Alginates/Hydrofibers Benefits: Provide a moist environment High absorptive capacity Conformable/cuttable (rope or sheet form) Provide hemostasis No adherence to moist wound bed
Hydrogels Benefits: Promote a moist environment Donate moisture to dry wounds Aid in autolytic debridement (rehydrate/soften necrotic tissue)
Hydrogels Indications: Drywounds Wounds with slough wounds Wounds with eschar Over tissues and tendons to prevent drying Contraindications: High exudate wounds Examples: Solosite, Woun’ Dress, SkinTegrity
Silicone Chemically inert, adverse effects rare Designed to be removed without trauma or pain Protect friable or newly healed tissue from injury Less trauma to periwound Examples: Mepilex, Allevyn Gentle
Enzymatic Debriders January 1, 2008 DESI drug changes Medicare Part D: Reimbursement Limitedfor products which contain papain/urea/chlorophyllin complex sodium What does that mean?? Increased cost to the patient
Enzymatic DebridersAlternatives Uses chemicals to break-down and digest necrotic tissue Must know mechanism of action to be effective Examples: Hypertonic saline, Enzymes, Honey
Antimicrobials Bact er i oci dal : Si l ver Honey Cadexom er i odi ne Bact er i ost at i c: M hyl ene Bl ue and Gent i an Vi ol et et Xer of or m
Silver Antimicrobial action through (+) silver ion Effective when in contact with wound fluid Consider: Kill rate AND sustained release rate Testing Methods: Simulated wound fluid, saline Delivery methods: foams, gels, alginates, hydrofibers, creams (SSD - approved for burns, only)
How does silver work?Bacteria elimination: 3 ways• Cell wall rupture• Prevents respiration or nutrient processing• Disturbs replicationConclusion:• Silver resistance unlikely silver secondary to 3 mechanisms• No cases of bacterial resistance to silver in vivo.
Antiseptics (+) Destroy or inhibit growth of microorganisms Efficacyon intact skin widely known and accepted (+) Resistance significantly less than antibiotics (-) In vitro cytotoxicity to cells of healing AHRQ: Caution against use NPUAP/EPUAP: Limited use to control bacterial bioburden
CollagenUsually Type I bovine or avian or type IIIporcine collagen Benefits: May accelerate wound healing Slight absorption May be used with topical agents Examples: Biostep, Fibracol, Puracol
Collagen Indications: Partial & full thickness wounds Minimal to moderate drainage Contraindications: Eschar covered Full thickness burns Sensitivity to contents
Bioengineered ProductsGrowth Factor Preparations Regranex® PDGF preparation in a hydrogelSingle-Layered Tissue Dermagraft® Human fibroblasts on matrix meshBilayered Tissue Apligraf® Human fibroblasts and keratinocytes in a bovine collagen matrix.
Who makes it? Organogenesis, Inc What is it? Dermal layer: human fibroblasts from neonatal foreskin in a bovine Type I collagen matrix Epidermal layer: human keratinocytes What does it do? Accelerates wound repair by secreting important cells and proteins (GF and cytokines) Indications: Venous Leg Ulcers and DM Foot Ulcers
Who makes it? Advanced BioHealing, Inc What is it? Human fibroblast (neonatal foreskin) derived dermal substitute Contains fibroblasts, ECM and bioabsorbable scaffold How does it work? Assists in the restoration of the dermal bed Fibroblasts proliferate to fill the interstices of the scaffold and secrete human dermal collagen, matrix proteins, GF, and cytokines to create a 3-dimensional human dermal substitue Indications: Full thickness DM > 6 wks duration without tendon, muscle, joint capsule or bone exposure
Graft Jacket Who makes it? Wright Medical Technology, Inc What is it? Donated human skin Removed the dermal and epidermal cells but preserved bioactive components (proteins, blood vessel channels) and structure What does it do? A 3-dimensional scaffold to support the body’s own natural repair process of cellular repopulation and vascularization Supports regeneration of host tissue Indications: DM
Who makes it? Healthpoint, Ltd What is it? Extracellular matrix composed of porcine small intestinal submucosa (SIS) How does it work? Provides a matrix for tissue repair Placed onto wound, cells/nutrients from adjacent tissues invade the matrix, capillary growth ensues New tissue formation by the body itself Indications: Partial and full thickness wounds, PrU, Venous ulcers, chronic vascular ulcers, DM, traumatic wounds, draining wounds, surgical wounds
In Conclusion Determine wound cause and address Establish plan of care that includes dressings that will address principles of moist wound healing Assure pain is addressed Through pharmacologic and non- pharmacologic methods